Intestinal helminths
mnlovely
4,137 views
102 slides
Jun 04, 2017
Slide 1 of 102
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
About This Presentation
MBBS Paediatric Lecture
Slide Content
CommonCommon
HELMINTHSHELMINTHS
(worms)(worms)
HELMINTHSHELMINTHS
(worms)(worms)
Gut Parasites: Gut Parasites: most prevalent in DCs (lack of most prevalent in DCs (lack of
sanitation): significant MM (impair physical & sanitation): significant MM (impair physical &
mental growth, education, economy)mental growth, education, economy)
–Helminths: Helminths: multicellular: usually cannot multiply in multicellular: usually cannot multiply in
human bodyhuman body
–4 gut H are soil-transmitted (STH) (geohelminths): 4 gut H are soil-transmitted (STH) (geohelminths): A. A.
lumbricoides, T. trichiuria (whipworm), A. duodenale, & lumbricoides, T. trichiuria (whipworm), A. duodenale, &
N. Americanicus (HW)N. Americanicus (HW)
–Protozoa Protozoa are unicellular & can multiply insideare unicellular & can multiply inside
sanitation): significant MM (impair physical & sanitation): significant MM (impair physical &
mental growth, education, economy)mental growth, education, economy)
–Helminths: Helminths: multicellular: usually cannot multiply in multicellular: usually cannot multiply in
human bodyhuman body
–4 gut H are soil-transmitted (STH) (geohelminths): 4 gut H are soil-transmitted (STH) (geohelminths): A. A.
lumbricoides, T. trichiuria (whipworm), A. duodenale, & lumbricoides, T. trichiuria (whipworm), A. duodenale, &
N. Americanicus (HW)N. Americanicus (HW)
–Protozoa Protozoa are unicellular & can multiply insideare unicellular & can multiply inside
HelminthsHelminths
•Nemathelminths: Nemathelminths: nematodes (round): ascaris, nematodes (round): ascaris,
encylostoma, enterobius, trichuris, dracunculus, encylostoma, enterobius, trichuris, dracunculus,
necator, strongyloides, tnecator, strongyloides, trichinella, richinella, filariafilaria
•Platyheminths Platyheminths (flat) (flat)
–Leaf like (Leaf like (trematodestrematodes: flukes): schistosoma : flukes): schistosoma
(blood F.), fasciola, chlonorchis, paragonimus(blood F.), fasciola, chlonorchis, paragonimus
–Tape like (Tape like (cystodescystodes, tape worm): taenia, , tape worm): taenia,
echinococcus, diphylobothriumechinococcus, diphylobothrium
•Nemathelminths: Nemathelminths: nematodes (round): ascaris, nematodes (round): ascaris,
encylostoma, enterobius, trichuris, dracunculus, encylostoma, enterobius, trichuris, dracunculus,
necator, strongyloides, tnecator, strongyloides, trichinella, richinella, filariafilaria
•Platyheminths Platyheminths (flat) (flat)
–Leaf like (Leaf like (trematodestrematodes: flukes): schistosoma : flukes): schistosoma
(blood F.), fasciola, chlonorchis, paragonimus(blood F.), fasciola, chlonorchis, paragonimus
–Tape like (Tape like (cystodescystodes, tape worm): taenia, , tape worm): taenia,
echinococcus, diphylobothriumechinococcus, diphylobothrium
Commonest gut protozoa: Commonest gut protozoa: G intestinalis, E histolytica, G intestinalis, E histolytica,
Cyclospora, Cryptosporidium. They cause Cyclospora, Cryptosporidium. They cause diarrhoeadiarrhoea
•Giardia Giardia is the commonest c/of D in the West, & is also v. is the commonest c/of D in the West, & is also v.
common in DCscommon in DCs
•AmebiasisAmebiasis: : 33
rdrd
c/of death c/of death from parasites in world, the from parasites in world, the
greatest impact in DCs. 50 million worldwide/y, with greatest impact in DCs. 50 million worldwide/y, with
100,000 deaths/y100,000 deaths/y
•CryptosporidiosisCryptosporidiosis: : most among AIDS & U-5most among AIDS & U-5
Protozoa spread by fecal contamination. The cysts are Protozoa spread by fecal contamination. The cysts are
relatively resistant to Cl. relatively resistant to Cl.
•Other protozoa in human gut are non-pathogenicOther protozoa in human gut are non-pathogenic
Cyclospora, Cryptosporidium. They cause Cyclospora, Cryptosporidium. They cause diarrhoeadiarrhoea
•Giardia Giardia is the commonest c/of D in the West, & is also v. is the commonest c/of D in the West, & is also v.
common in DCscommon in DCs
•AmebiasisAmebiasis: : 33
rdrd
c/of death c/of death from parasites in world, the from parasites in world, the
greatest impact in DCs. 50 million worldwide/y, with greatest impact in DCs. 50 million worldwide/y, with
100,000 deaths/y100,000 deaths/y
•CryptosporidiosisCryptosporidiosis: : most among AIDS & U-5most among AIDS & U-5
Protozoa spread by fecal contamination. The cysts are Protozoa spread by fecal contamination. The cysts are
relatively resistant to Cl. relatively resistant to Cl.
•Other protozoa in human gut are non-pathogenicOther protozoa in human gut are non-pathogenic
BangladeshBangladesh
•Worms among <2y age: Worms among <2y age: 80%. 80%. First acquisition at First acquisition at
14mo 14mo (1-24 mo). (1-24 mo). Common:Common: AL (commonest), AL (commonest),
TT, EV, AD/NA, & mixed. Mostly a/with DTT, EV, AD/NA, & mixed. Mostly a/with D
•Re-infested after 3mo. of DW: Re-infested after 3mo. of DW: 66%66%
•Risks: Risks: open disposal of feces, poor hand hygiene, open disposal of feces, poor hand hygiene,
bare foot, surface water for washingbare foot, surface water for washing
•Safe disposal of feces: 35% reduction, tube well Safe disposal of feces: 35% reduction, tube well
water 48%, breastfeeding 16%water 48%, breastfeeding 16%
•Awareness & DW are crucial to preventionAwareness & DW are crucial to prevention
DW= dewormingDW= deworming
•Worms among <2y age: Worms among <2y age: 80%. 80%. First acquisition at First acquisition at
14mo 14mo (1-24 mo). (1-24 mo). Common:Common: AL (commonest), AL (commonest),
TT, EV, AD/NA, & mixed. Mostly a/with DTT, EV, AD/NA, & mixed. Mostly a/with D
•Re-infested after 3mo. of DW: Re-infested after 3mo. of DW: 66%66%
•Risks: Risks: open disposal of feces, poor hand hygiene, open disposal of feces, poor hand hygiene,
bare foot, surface water for washingbare foot, surface water for washing
•Safe disposal of feces: 35% reduction, tube well Safe disposal of feces: 35% reduction, tube well
water 48%, breastfeeding 16%water 48%, breastfeeding 16%
•Awareness & DW are crucial to preventionAwareness & DW are crucial to prevention
DW= dewormingDW= deworming
•The egg load for AL was highestThe egg load for AL was highest
•Worldwide:Worldwide:
– AL:AL: 1.2 billion 1.2 billion
– TT: 795 millionTT: 795 million
– AD/NA 740 millionAD/NA 740 million
•Disability-adjusted life years (DALYs): Disability-adjusted life years (DALYs):
–22.1 million lost for hookworm22.1 million lost for hookworm
–10.5 million for AL10.5 million for AL
–6.4 million for TT6.4 million for TT
•Worldwide:Worldwide:
– AL:AL: 1.2 billion 1.2 billion
– TT: 795 millionTT: 795 million
– AD/NA 740 millionAD/NA 740 million
•Disability-adjusted life years (DALYs): Disability-adjusted life years (DALYs):
–22.1 million lost for hookworm22.1 million lost for hookworm
–10.5 million for AL10.5 million for AL
–6.4 million for TT6.4 million for TT
Ascaris Ascaris
lumbricoideslumbricoides
lumbricoideslumbricoides
ETIOLOGY/ EPIDEMIOLOGYETIOLOGY/ EPIDEMIOLOGY
•AL AL is the most widespread human gut nematodeis the most widespread human gut nematode
•Commonest in tropics: poor sanitation, human feces Commonest in tropics: poor sanitation, human feces
used as fertilizerused as fertilizer
•No direct P2P transmission. IP: 8wNo direct P2P transmission. IP: 8w
•Adult AL live in lumen of Adult AL live in lumen of small gutsmall gut. Female makes . Female makes
200,000 eggs/d to excrete in stool. Eggs must 200,000 eggs/d to excrete in stool. Eggs must incubate incubate
in soil 2-3w to become infectiousin soil 2-3w to become infectious
•AL AL is the most widespread human gut nematodeis the most widespread human gut nematode
•Commonest in tropics: poor sanitation, human feces Commonest in tropics: poor sanitation, human feces
used as fertilizerused as fertilizer
•No direct P2P transmission. IP: 8wNo direct P2P transmission. IP: 8w
•Adult AL live in lumen of Adult AL live in lumen of small gutsmall gut. Female makes . Female makes
200,000 eggs/d to excrete in stool. Eggs must 200,000 eggs/d to excrete in stool. Eggs must incubate incubate
in soil 2-3w to become infectiousin soil 2-3w to become infectious
Life CycleLife Cycle
• AL AL adult worms (1) live in small gut lumen; eggs adult worms (1) live in small gut lumen; eggs ÞÞ
passed in feces (2)passed in feces (2)
•Unfertilized eggs are not infectiveUnfertilized eggs are not infective
•Embryonated eggs (3) are swallowed (4) Embryonated eggs (3) are swallowed (4) ÞÞ larvae hatch larvae hatch
out (5) out (5) ÞÞ invade gut wall invade gut wall ÞÞ carried (via portal) to carried (via portal) to
lungs (6). Larvae mature further there (10-14d) lungs (6). Larvae mature further there (10-14d) ÞÞ
ascend ascend ÞÞ swallowed (7) swallowed (7)
•Reaching gut they mature to adults (8)Reaching gut they mature to adults (8)
•2-3 mo are required for LC2-3 mo are required for LC
•Adult worms can live 1-2yAdult worms can live 1-2y
• AL AL adult worms (1) live in small gut lumen; eggs adult worms (1) live in small gut lumen; eggs ÞÞ
passed in feces (2)passed in feces (2)
•Unfertilized eggs are not infectiveUnfertilized eggs are not infective
•Embryonated eggs (3) are swallowed (4) Embryonated eggs (3) are swallowed (4) ÞÞ larvae hatch larvae hatch
out (5) out (5) ÞÞ invade gut wall invade gut wall ÞÞ carried (via portal) to carried (via portal) to
lungs (6). Larvae mature further there (10-14d) lungs (6). Larvae mature further there (10-14d) ÞÞ
ascend ascend ÞÞ swallowed (7) swallowed (7)
•Reaching gut they mature to adults (8)Reaching gut they mature to adults (8)
•2-3 mo are required for LC2-3 mo are required for LC
•Adult worms can live 1-2yAdult worms can live 1-2y
An adult female (genital An adult female (genital
girdle: dark circular groove) girdle: dark circular groove)
AL: tapered ends; length 15-AL: tapered ends; length 15-
35cm (females is larger). as 35cm (females is larger). as
evidenced by the size and). evidenced by the size and).
Larva hatch from egg in small gut
girdle: dark circular groove) girdle: dark circular groove)
AL: tapered ends; length 15-AL: tapered ends; length 15-
35cm (females is larger). as 35cm (females is larger). as
evidenced by the size and). evidenced by the size and).
Larva hatch from egg in small gut
CL. MANIFESTATIONSCL. MANIFESTATIONS
Mostly Mostly asymptomatic!asymptomatic!
•Moderate-heavy load: Moderate-heavy load: Mn, nonsp. GIT SS. Intestinal obs., Mn, nonsp. GIT SS. Intestinal obs.,
more in children (narrow lumen)more in children (narrow lumen)
•Larval Larval migrationmigration: : Löffler syn., marked eosinophiliaLöffler syn., marked eosinophilia
•Worm Worm migrationmigration: : peritonitis 2y to penetration, CBD obs. peritonitis 2y to penetration, CBD obs.
(biliary colic, cholangitis, pancreatitis), appendicitis. (biliary colic, cholangitis, pancreatitis), appendicitis.
Migrate more on Migrate more on stressesstresses: F, illness, anesthesia; some : F, illness, anesthesia; some
anthelmintics, O2anthelmintics, O2
SS=symptoms & signsSS=symptoms & signs
Mostly Mostly asymptomatic!asymptomatic!
•Moderate-heavy load: Moderate-heavy load: Mn, nonsp. GIT SS. Intestinal obs., Mn, nonsp. GIT SS. Intestinal obs.,
more in children (narrow lumen)more in children (narrow lumen)
•Larval Larval migrationmigration: : Löffler syn., marked eosinophiliaLöffler syn., marked eosinophilia
•Worm Worm migrationmigration: : peritonitis 2y to penetration, CBD obs. peritonitis 2y to penetration, CBD obs.
(biliary colic, cholangitis, pancreatitis), appendicitis. (biliary colic, cholangitis, pancreatitis), appendicitis.
Migrate more on Migrate more on stressesstresses: F, illness, anesthesia; some : F, illness, anesthesia; some
anthelmintics, O2anthelmintics, O2
SS=symptoms & signsSS=symptoms & signs
DIAGNOSISDIAGNOSIS
•Ova in stoolOva in stool
•Passage of adult worms via Passage of adult worms via
rectum, nose or mouth rectum, nose or mouth
L: L: fertilized egg, fertilized egg,
unicellular, unicellular,
requires 18d & requires 18d &
favorable favorable
conditions to be conditions to be
infective. infective. R: R:
unfertilized eggunfertilized egg
•Ova in stoolOva in stool
•Passage of adult worms via Passage of adult worms via
rectum, nose or mouth rectum, nose or mouth
L: L: fertilized egg, fertilized egg,
unicellular, unicellular,
requires 18d & requires 18d &
favorable favorable
conditions to be conditions to be
infective. infective. R: R:
unfertilized eggunfertilized egg
TREATMENTTREATMENT
•Pyrantel pamoate or albendazole s. dose for Pyrantel pamoate or albendazole s. dose for
aged 2 or moreaged 2 or more
•Mebendazole for 3 days for aged 2 or moreMebendazole for 3 days for aged 2 or more
•Reexamination of stool 3 w later for clearanceReexamination of stool 3 w later for clearance
•Pyrantel pamoate or albendazole s. dose for Pyrantel pamoate or albendazole s. dose for
aged 2 or moreaged 2 or more
•Mebendazole for 3 days for aged 2 or moreMebendazole for 3 days for aged 2 or more
•Reexamination of stool 3 w later for clearanceReexamination of stool 3 w later for clearance
•Gut obstruction: Gut obstruction:
–piperazine (75 mg/kg/d, not >3.5g) can worsen piperazine (75 mg/kg/d, not >3.5g) can worsen
obstruction; conservative suction, IVF may resolve, then obstruction; conservative suction, IVF may resolve, then
albendazole/mebendazole may be givenalbendazole/mebendazole may be given
•Surgery may be necessary to relieve gut or biliary Surgery may be necessary to relieve gut or biliary
obstruction or for volvulus or peritonitis from obstruction or for volvulus or peritonitis from
perforation. Massaging gut to eliminate obs. is perforation. Massaging gut to eliminate obs. is preferable preferable
to incision in surgeryto incision in surgery
•ERCP: for extraction of worms from the biliary treeERCP: for extraction of worms from the biliary tree
–piperazine (75 mg/kg/d, not >3.5g) can worsen piperazine (75 mg/kg/d, not >3.5g) can worsen
obstruction; conservative suction, IVF may resolve, then obstruction; conservative suction, IVF may resolve, then
albendazole/mebendazole may be givenalbendazole/mebendazole may be given
•Surgery may be necessary to relieve gut or biliary Surgery may be necessary to relieve gut or biliary
obstruction or for volvulus or peritonitis from obstruction or for volvulus or peritonitis from
perforation. Massaging gut to eliminate obs. is perforation. Massaging gut to eliminate obs. is preferable preferable
to incision in surgeryto incision in surgery
•ERCP: for extraction of worms from the biliary treeERCP: for extraction of worms from the biliary tree
CONTROL MEASURESCONTROL MEASURES
•Sanitary disposal of human fecesSanitary disposal of human feces
•Hand hygieneHand hygiene
•Children’s play areas need special attentionChildren’s play areas need special attention
•Vegetables cultivated using uncomposted human feces Vegetables cultivated using uncomposted human feces
must be well cooked or soaked in a diluted iodine must be well cooked or soaked in a diluted iodine
solution. Household bleach is ineffectivesolution. Household bleach is ineffective
•Periodic deworming at schoolsPeriodic deworming at schools
•Sanitary disposal of human fecesSanitary disposal of human feces
•Hand hygieneHand hygiene
•Children’s play areas need special attentionChildren’s play areas need special attention
•Vegetables cultivated using uncomposted human feces Vegetables cultivated using uncomposted human feces
must be well cooked or soaked in a diluted iodine must be well cooked or soaked in a diluted iodine
solution. Household bleach is ineffectivesolution. Household bleach is ineffective
•Periodic deworming at schoolsPeriodic deworming at schools
Löeffler SyndromeLöeffler Syndrome
or Ac. Simple Pulmonary Eosinophilia. or Ac. Simple Pulmonary Eosinophilia. Rare. Typically as Rare. Typically as
transient CXR infiltrates, transient CXR infiltrates, mildmild system upset, system upset,
eosinophilia. Incidence: 6/100,000eosinophilia. Incidence: 6/100,000
Pathology: Pathology: a number of allergens are linked:a number of allergens are linked:
parasites: parasites: ascaris, strongyloides, ankylostoma, microfilaria, ascaris, strongyloides, ankylostoma, microfilaria,
toxocaratoxocara
drugs: drugs: aspirin, penicillin, sulphasaspirin, penicillin, sulphas
SS: SS: usually usually mild: mild: tacypnoea, rashes, SoB, wheeze,tacypnoea, rashes, SoB, wheeze, chest p., dry chest p., dry
cough, F, malaise, HA, myalgia, anorexiacough, F, malaise, HA, myalgia, anorexia
or Ac. Simple Pulmonary Eosinophilia. or Ac. Simple Pulmonary Eosinophilia. Rare. Typically as Rare. Typically as
transient CXR infiltrates, transient CXR infiltrates, mildmild system upset, system upset,
eosinophilia. Incidence: 6/100,000eosinophilia. Incidence: 6/100,000
Pathology: Pathology: a number of allergens are linked:a number of allergens are linked:
parasites: parasites: ascaris, strongyloides, ankylostoma, microfilaria, ascaris, strongyloides, ankylostoma, microfilaria,
toxocaratoxocara
drugs: drugs: aspirin, penicillin, sulphasaspirin, penicillin, sulphas
SS: SS: usually usually mild: mild: tacypnoea, rashes, SoB, wheeze,tacypnoea, rashes, SoB, wheeze, chest p., dry chest p., dry
cough, F, malaise, HA, myalgia, anorexiacough, F, malaise, HA, myalgia, anorexia
Dx Dx
XR: XR: Often a fleeting transient non-segmental lung Often a fleeting transient non-segmental lung
opacity (unilateral/bi-) more on periphery. Pleural E. & opacity (unilateral/bi-) more on periphery. Pleural E. &
LAP is absentLAP is absent
Eosinophilia, Hyper IgEEosinophilia, Hyper IgE
Rx: Rx: usually usually not required. not required. It resolves within a month (self-It resolves within a month (self-
limited). Rx underlying cause. In some cases steroids. limited). Rx underlying cause. In some cases steroids. DECDEC
DD: DD: recurrent aspiration, BA, pulmonary hge., pulmonary recurrent aspiration, BA, pulmonary hge., pulmonary
vasculitis, cryptogenic organising pneumonia (COP)vasculitis, cryptogenic organising pneumonia (COP)
XR: XR: Often a fleeting transient non-segmental lung Often a fleeting transient non-segmental lung
opacity (unilateral/bi-) more on periphery. Pleural E. & opacity (unilateral/bi-) more on periphery. Pleural E. &
LAP is absentLAP is absent
Eosinophilia, Hyper IgEEosinophilia, Hyper IgE
Rx: Rx: usually usually not required. not required. It resolves within a month (self-It resolves within a month (self-
limited). Rx underlying cause. In some cases steroids. limited). Rx underlying cause. In some cases steroids. DECDEC
DD: DD: recurrent aspiration, BA, pulmonary hge., pulmonary recurrent aspiration, BA, pulmonary hge., pulmonary
vasculitis, cryptogenic organising pneumonia (COP)vasculitis, cryptogenic organising pneumonia (COP)
Symmetric bilateral infiltrates in LSSymmetric bilateral infiltrates in LS
CT confirmed dense patchy interstitial CT confirmed dense patchy interstitial
infiltratesinfiltrates
CT confirmed dense patchy interstitial CT confirmed dense patchy interstitial
infiltratesinfiltrates
A: CXR: diffuse fine nodules. B: CT: widespread, bilateral fine micronodules. C, D: A: CXR: diffuse fine nodules. B: CT: widespread, bilateral fine micronodules. C, D:
lung biopsy: eosinophilic infiltration of alveolar spaceslung biopsy: eosinophilic infiltration of alveolar spaces
lung biopsy: eosinophilic infiltration of alveolar spaceslung biopsy: eosinophilic infiltration of alveolar spaces
((Ancylostoma Ancylostoma
duodenale/duodenale/
Necator americanusNecator americanus))
HookwormHookworm
duodenale/duodenale/
Necator americanusNecator americanus))
HookwormHookworm
ETIOLOGYETIOLOGY
•Infestation usually is caused byInfestation usually is caused by
–A duodenaleA duodenale or or
–Necator americanusNecator americanus
2 roundworms (nematodes) with similar LC 2 roundworms (nematodes) with similar LC
•Infestation usually is caused byInfestation usually is caused by
–A duodenaleA duodenale or or
–Necator americanusNecator americanus
2 roundworms (nematodes) with similar LC 2 roundworms (nematodes) with similar LC
EPIDEMIOLOGYEPIDEMIOLOGY
•Humans are major reservoir. More in rural areas (soil Humans are major reservoir. More in rural areas (soil
contamination with human feces)contamination with human feces)
•Both are prevalent, but Both are prevalent, but NANA more in the West, Africa, SEA more in the West, Africa, SEA
•Larvae & eggs survive in loose, moist, shady, aerated, Larvae & eggs survive in loose, moist, shady, aerated,
warm soil (temp. 23–33°C)warm soil (temp. 23–33°C)
•Skin infestation occurs by larvaeSkin infestation occurs by larvae
•LC: LC: 4-12 w4-12 w
•Humans are major reservoir. More in rural areas (soil Humans are major reservoir. More in rural areas (soil
contamination with human feces)contamination with human feces)
•Both are prevalent, but Both are prevalent, but NANA more in the West, Africa, SEA more in the West, Africa, SEA
•Larvae & eggs survive in loose, moist, shady, aerated, Larvae & eggs survive in loose, moist, shady, aerated,
warm soil (temp. 23–33°C)warm soil (temp. 23–33°C)
•Skin infestation occurs by larvaeSkin infestation occurs by larvae
•LC: LC: 4-12 w4-12 w
LIFE CYCLELIFE CYCLE
•Eggs in stool (1) & in favorable moisture, warmth, shade, Eggs in stool (1) & in favorable moisture, warmth, shade,
larvae hatch in 1-2dlarvae hatch in 1-2d
•Rhabditiform larvae grow (2) in 5-10d (2 molts) to become Rhabditiform larvae grow (2) in 5-10d (2 molts) to become
filariform (infective) (3); can survive 3-4w filariform (infective) (3); can survive 3-4w ÞÞ
penetrate skin & are carried to lungs penetrate skin & are carried to lungs ÞÞ ascend to ascend to
pharynx pharynx ÞÞ are swallowed (4) are swallowed (4)
•The larvae reach small gut & mature to adults The larvae reach small gut & mature to adults ÞÞ attach to attach to
gut wall to suck blood (5)gut wall to suck blood (5)
•Worms can live 5-15 y, but a 70% decrease within 1-2yWorms can live 5-15 y, but a 70% decrease within 1-2y
•Eggs in stool (1) & in favorable moisture, warmth, shade, Eggs in stool (1) & in favorable moisture, warmth, shade,
larvae hatch in 1-2dlarvae hatch in 1-2d
•Rhabditiform larvae grow (2) in 5-10d (2 molts) to become Rhabditiform larvae grow (2) in 5-10d (2 molts) to become
filariform (infective) (3); can survive 3-4w filariform (infective) (3); can survive 3-4w ÞÞ
penetrate skin & are carried to lungs penetrate skin & are carried to lungs ÞÞ ascend to ascend to
pharynx pharynx ÞÞ are swallowed (4) are swallowed (4)
•The larvae reach small gut & mature to adults The larvae reach small gut & mature to adults ÞÞ attach to attach to
gut wall to suck blood (5)gut wall to suck blood (5)
•Worms can live 5-15 y, but a 70% decrease within 1-2yWorms can live 5-15 y, but a 70% decrease within 1-2y
HW rhabditiform larvaHW rhabditiform larva
HW filariform larvaHW filariform larva
HW filariform larvaHW filariform larva
HW on gut wallHW on gut wall
CL. MANIFESTATIONSCL. MANIFESTATIONS
Mostly Mostly asymptomaticasymptomatic
•Common c/of IDA in DCsCommon c/of IDA in DCs
•Heavy load causes MnHeavy load causes Mn
•Skin infestation (usually feet): a stinging/burning itchy Skin infestation (usually feet): a stinging/burning itchy
papulovesicular rash (ground itch) ~1-2wpapulovesicular rash (ground itch) ~1-2w
•Löffler is uncommonLöffler is uncommon
•AP, NVD & marked eosinophilia 4-6w laterAP, NVD & marked eosinophilia 4-6w later
Mostly Mostly asymptomaticasymptomatic
•Common c/of IDA in DCsCommon c/of IDA in DCs
•Heavy load causes MnHeavy load causes Mn
•Skin infestation (usually feet): a stinging/burning itchy Skin infestation (usually feet): a stinging/burning itchy
papulovesicular rash (ground itch) ~1-2wpapulovesicular rash (ground itch) ~1-2w
•Löffler is uncommonLöffler is uncommon
•AP, NVD & marked eosinophilia 4-6w laterAP, NVD & marked eosinophilia 4-6w later
DxDx
•Eggs in feces. 8-12w required after infestation for eggs in Eggs in feces. 8-12w required after infestation for eggs in
fecesfeces
•Adult worms rarely are seenAdult worms rarely are seen
HW eggs (HW eggs (AD/NAAD/NA cannot be DD). The embryo (right) has begun cell cannot be DD). The embryo (right) has begun cell
divisiondivision
•Eggs in feces. 8-12w required after infestation for eggs in Eggs in feces. 8-12w required after infestation for eggs in
fecesfeces
•Adult worms rarely are seenAdult worms rarely are seen
HW eggs (HW eggs (AD/NAAD/NA cannot be DD). The embryo (right) has begun cell cannot be DD). The embryo (right) has begun cell
divisiondivision
TREATMENTTREATMENT
•Albendazole, mebendazole, pyrantel p. effectiveAlbendazole, mebendazole, pyrantel p. effective
•½ adult dose of albendazole/mebendazole in <2y½ adult dose of albendazole/mebendazole in <2y
•In heavy load during pregnancy, deworm during 2In heavy load during pregnancy, deworm during 2
ndnd
- 3 - 3
rdrd
TM with above drugsTM with above drugs
•A repeated stool exam, 2w later, retreat SOSA repeated stool exam, 2w later, retreat SOS
•Supplementation with ironSupplementation with iron
•Albendazole, mebendazole, pyrantel p. effectiveAlbendazole, mebendazole, pyrantel p. effective
•½ adult dose of albendazole/mebendazole in <2y½ adult dose of albendazole/mebendazole in <2y
•In heavy load during pregnancy, deworm during 2In heavy load during pregnancy, deworm during 2
ndnd
- 3 - 3
rdrd
TM with above drugsTM with above drugs
•A repeated stool exam, 2w later, retreat SOSA repeated stool exam, 2w later, retreat SOS
•Supplementation with ironSupplementation with iron
CONTROL MEASURESCONTROL MEASURES
•Sanitary disposal of fecesSanitary disposal of feces
•Rx of all infested people & screening of children & Rx of all infested people & screening of children &
agricultural workers in endemic areasagricultural workers in endemic areas
•Wearing shoes & full dressWearing shoes & full dress
•Periodic dewormingPeriodic deworming
•Sanitary disposal of fecesSanitary disposal of feces
•Rx of all infested people & screening of children & Rx of all infested people & screening of children &
agricultural workers in endemic areasagricultural workers in endemic areas
•Wearing shoes & full dressWearing shoes & full dress
•Periodic dewormingPeriodic deworming
Enterobius Enterobius
vermicularisvermicularis
((PinwormPinworm))
vermicularisvermicularis
((PinwormPinworm))
ETIOLOGY/EPIDEMIOLOGYETIOLOGY/EPIDEMIOLOGY
•E vermicularisE vermicularis is a is a nematodenematode
•V. common. Worldwide. V. common. Worldwide. HumansHumans only only
•Commonly as clusters of cases in familiesCommonly as clusters of cases in families
•More in small children, in caregiversMore in small children, in caregivers
•50% institutionalized people may be infected50% institutionalized people may be infected
•Egg by fecal-oral route or contaminated hands/fomitesEgg by fecal-oral route or contaminated hands/fomites
•Adults live in Adults live in coloncolon
•Females die Females die after laying eggsafter laying eggs
•Eggs become infective in 2-3w. LC: 1-2 moEggs become infective in 2-3w. LC: 1-2 mo
•E vermicularisE vermicularis is a is a nematodenematode
•V. common. Worldwide. V. common. Worldwide. HumansHumans only only
•Commonly as clusters of cases in familiesCommonly as clusters of cases in families
•More in small children, in caregiversMore in small children, in caregivers
•50% institutionalized people may be infected50% institutionalized people may be infected
•Egg by fecal-oral route or contaminated hands/fomitesEgg by fecal-oral route or contaminated hands/fomites
•Adults live in Adults live in coloncolon
•Females die Females die after laying eggsafter laying eggs
•Eggs become infective in 2-3w. LC: 1-2 moEggs become infective in 2-3w. LC: 1-2 mo
CL. MANIFESTATIONSCL. MANIFESTATIONS
Some specially adults are Some specially adults are asymptomaticasymptomatic
•May cause May cause pruritus ani pruritus ani & & pruritus vulvaepruritus vulvae
•Frequency of micturitionFrequency of micturition
•Can be found in appendix, but cause no appendicitisCan be found in appendix, but cause no appendicitis
•Teeth grinding, wt. loss, enuresis are not from itTeeth grinding, wt. loss, enuresis are not from it
•Urethritis, vaginitis, salpingitis, or PID may occur from Urethritis, vaginitis, salpingitis, or PID may occur from
migration of adult wormsmigration of adult worms
Some specially adults are Some specially adults are asymptomaticasymptomatic
•May cause May cause pruritus ani pruritus ani & & pruritus vulvaepruritus vulvae
•Frequency of micturitionFrequency of micturition
•Can be found in appendix, but cause no appendicitisCan be found in appendix, but cause no appendicitis
•Teeth grinding, wt. loss, enuresis are not from itTeeth grinding, wt. loss, enuresis are not from it
•Urethritis, vaginitis, salpingitis, or PID may occur from Urethritis, vaginitis, salpingitis, or PID may occur from
migration of adult wormsmigration of adult worms
(1)(1)Eggs are deposited on perianal folds. (2) Eggs are deposited on perianal folds. (2) Self-infectionSelf-infection
occurs by putting eggs to mouth with hands. P2P occurs by putting eggs to mouth with hands. P2P
transmission through clothes or bed linens. Some eggs transmission through clothes or bed linens. Some eggs
may become airborne & swallowed. (3) From ingested may become airborne & swallowed. (3) From ingested
infective eggs, larvae hatch in small gut. (4) Adults infective eggs, larvae hatch in small gut. (4) Adults
settle in colon (2mo). (5) Gravid females migrate settle in colon (2mo). (5) Gravid females migrate
nocturnally outside anus & oviposit. Larvae inside eggs nocturnally outside anus & oviposit. Larvae inside eggs
develop (infective) in 4-6h (1)develop (infective) in 4-6h (1)
•LC: LC: 1 mo 1 mo
•Retroinfection Retroinfection (migration of newly larvae from anal skin (migration of newly larvae from anal skin
back into rectum), may occur back into rectum), may occur
LIFE CYCLELIFE CYCLE
occurs by putting eggs to mouth with hands. P2P occurs by putting eggs to mouth with hands. P2P
transmission through clothes or bed linens. Some eggs transmission through clothes or bed linens. Some eggs
may become airborne & swallowed. (3) From ingested may become airborne & swallowed. (3) From ingested
infective eggs, larvae hatch in small gut. (4) Adults infective eggs, larvae hatch in small gut. (4) Adults
settle in colon (2mo). (5) Gravid females migrate settle in colon (2mo). (5) Gravid females migrate
nocturnally outside anus & oviposit. Larvae inside eggs nocturnally outside anus & oviposit. Larvae inside eggs
develop (infective) in 4-6h (1)develop (infective) in 4-6h (1)
•LC: LC: 1 mo 1 mo
•Retroinfection Retroinfection (migration of newly larvae from anal skin (migration of newly larvae from anal skin
back into rectum), may occur back into rectum), may occur
LIFE CYCLELIFE CYCLE
DxDx
•Usually by seeing adults in perianum (best 2-3h after the Usually by seeing adults in perianum (best 2-3h after the
child is asleep)child is asleep)
•Very few ova are seen in stool; so, not recommendedVery few ova are seen in stool; so, not recommended
•Adhesive tape Adhesive tape on perianal skin to collect eggs (90% in 3 on perianal skin to collect eggs (90% in 3
consecutive samples) when pt. awakens in morningconsecutive samples) when pt. awakens in morning
•Anal swabs Anal swabs ("Swube tubes:" paddles coated with adhesive ("Swube tubes:" paddles coated with adhesive
material) may also be usedmaterial) may also be used
•Usually by seeing adults in perianum (best 2-3h after the Usually by seeing adults in perianum (best 2-3h after the
child is asleep)child is asleep)
•Very few ova are seen in stool; so, not recommendedVery few ova are seen in stool; so, not recommended
•Adhesive tape Adhesive tape on perianal skin to collect eggs (90% in 3 on perianal skin to collect eggs (90% in 3
consecutive samples) when pt. awakens in morningconsecutive samples) when pt. awakens in morning
•Anal swabs Anal swabs ("Swube tubes:" paddles coated with adhesive ("Swube tubes:" paddles coated with adhesive
material) may also be usedmaterial) may also be used
Pinworm: AB: eggs. C eggs on
cellulose tape prepn.
cellulose tape prepn.
Pinworm: adult in perianal area. Perianal inspection 2-
3h after child goes asleep may reveal it
3h after child goes asleep may reveal it
TREATMENTTREATMENT
•DoC: DoC: mebendazole, pyrantel p., albendazole (single dose, mebendazole, pyrantel p., albendazole (single dose,
repeated after 2w). All family m. are Rx. togetherrepeated after 2w). All family m. are Rx. together
•Others: piperazine & pyrvinium pamoate (less effective)Others: piperazine & pyrvinium pamoate (less effective)
•ReinfectionReinfection is v. common. Morning bath removes a large is v. common. Morning bath removes a large
proportion of eggs. Frequently changing underwares, proportion of eggs. Frequently changing underwares,
bed linens may reduce egg load & decrease reinfectionbed linens may reduce egg load & decrease reinfection
•Hand washing, keeping nails short, avoiding scratching of Hand washing, keeping nails short, avoiding scratching of
perianal region & nail biting may decrease perianal region & nail biting may decrease
autoinfection & transmissionautoinfection & transmission
•Repeated infections are treated the same wayRepeated infections are treated the same way
•DoC: DoC: mebendazole, pyrantel p., albendazole (single dose, mebendazole, pyrantel p., albendazole (single dose,
repeated after 2w). All family m. are Rx. togetherrepeated after 2w). All family m. are Rx. together
•Others: piperazine & pyrvinium pamoate (less effective)Others: piperazine & pyrvinium pamoate (less effective)
•ReinfectionReinfection is v. common. Morning bath removes a large is v. common. Morning bath removes a large
proportion of eggs. Frequently changing underwares, proportion of eggs. Frequently changing underwares,
bed linens may reduce egg load & decrease reinfectionbed linens may reduce egg load & decrease reinfection
•Hand washing, keeping nails short, avoiding scratching of Hand washing, keeping nails short, avoiding scratching of
perianal region & nail biting may decrease perianal region & nail biting may decrease
autoinfection & transmissionautoinfection & transmission
•Repeated infections are treated the same wayRepeated infections are treated the same way
CONTROL MEASURESCONTROL MEASURES
•Control is difficult in child care centers & schools, because Control is difficult in child care centers & schools, because
of high reinfectionof high reinfection
•Mass & simultaneous Rx, repeated after 2w, can be Mass & simultaneous Rx, repeated after 2w, can be
effectiveeffective
•Good hand hygiene is the most effectiveGood hand hygiene is the most effective
•Control is difficult in child care centers & schools, because Control is difficult in child care centers & schools, because
of high reinfectionof high reinfection
•Mass & simultaneous Rx, repeated after 2w, can be Mass & simultaneous Rx, repeated after 2w, can be
effectiveeffective
•Good hand hygiene is the most effectiveGood hand hygiene is the most effective
Trichinella Trichinella
spiralis spiralis
(Trichinosis)(Trichinosis)
spiralis spiralis
(Trichinosis)(Trichinosis)
ETIOLOGYETIOLOGY
T spiralisT spiralis
•5 species are capable of infecting. 5 species are capable of infecting. TT spiralisspiralis is the is the
commonest c/of human inf.commonest c/of human inf.
T spiralisT spiralis
•5 species are capable of infecting. 5 species are capable of infecting. TT spiralisspiralis is the is the
commonest c/of human inf.commonest c/of human inf.
EPIDEMIOLOGYEPIDEMIOLOGY
•It is enzootic worldwide in many carnivores, especially It is enzootic worldwide in many carnivores, especially
scavengersscavengers
•Inf occurs from ingesting raw/insufficiently cooked meat Inf occurs from ingesting raw/insufficiently cooked meat
containing encysted larvae of containing encysted larvae of T spiralis.T spiralis. The usual The usual
source of human inf. is pork, but horse meat & wild source of human inf. is pork, but horse meat & wild
carnivorous game, can be sources. Feeding pigs carnivorous game, can be sources. Feeding pigs uncooked uncooked
garbage perpetuates the cycle of inf. garbage perpetuates the cycle of inf.
•It is not transmitted from P2P It is not transmitted from P2P
•IPIP usually is 1-2w usually is 1-2w
•It is enzootic worldwide in many carnivores, especially It is enzootic worldwide in many carnivores, especially
scavengersscavengers
•Inf occurs from ingesting raw/insufficiently cooked meat Inf occurs from ingesting raw/insufficiently cooked meat
containing encysted larvae of containing encysted larvae of T spiralis.T spiralis. The usual The usual
source of human inf. is pork, but horse meat & wild source of human inf. is pork, but horse meat & wild
carnivorous game, can be sources. Feeding pigs carnivorous game, can be sources. Feeding pigs uncooked uncooked
garbage perpetuates the cycle of inf. garbage perpetuates the cycle of inf.
•It is not transmitted from P2P It is not transmitted from P2P
•IPIP usually is 1-2w usually is 1-2w
LIFE CYCLELIFE CYCLE
•Meat containing encysted larvae Meat containing encysted larvae (1) (1) of of TSTS. In stomach, . In stomach,
larvae are released larvae are released (2); (2); invade small gut wall, develop invade small gut wall, develop as as
adults adults (3) (3) (F, 2.2 mm; M, 1.2 mm; life span in small (F, 2.2 mm; M, 1.2 mm; life span in small gut gut
is 4w). After 1w, the F release larvae is 4w). After 1w, the F release larvae (4) (4) that that migrate to migrate to
striated muscles where they encyst (5). striated muscles where they encyst (5). Encystment is Encystment is
completed in 4-5w & larvae may live for completed in 4-5w & larvae may live for several yearsseveral years
•Rodents mainly maintain endemicity. Carnivores/ Rodents mainly maintain endemicity. Carnivores/
omnivores, like pigs/bears, feed on infected rodents or omnivores, like pigs/bears, feed on infected rodents or
other animalsother animals
•Humans are accidentally infected when eating improperly Humans are accidentally infected when eating improperly
cooked meat of these carnivorous animalscooked meat of these carnivorous animals
•Meat containing encysted larvae Meat containing encysted larvae (1) (1) of of TSTS. In stomach, . In stomach,
larvae are released larvae are released (2); (2); invade small gut wall, develop invade small gut wall, develop as as
adults adults (3) (3) (F, 2.2 mm; M, 1.2 mm; life span in small (F, 2.2 mm; M, 1.2 mm; life span in small gut gut
is 4w). After 1w, the F release larvae is 4w). After 1w, the F release larvae (4) (4) that that migrate to migrate to
striated muscles where they encyst (5). striated muscles where they encyst (5). Encystment is Encystment is
completed in 4-5w & larvae may live for completed in 4-5w & larvae may live for several yearsseveral years
•Rodents mainly maintain endemicity. Carnivores/ Rodents mainly maintain endemicity. Carnivores/
omnivores, like pigs/bears, feed on infected rodents or omnivores, like pigs/bears, feed on infected rodents or
other animalsother animals
•Humans are accidentally infected when eating improperly Humans are accidentally infected when eating improperly
cooked meat of these carnivorous animalscooked meat of these carnivorous animals
CL. MANIFESTATIONSCL. MANIFESTATIONS
Mostly Mostly inapparent. inapparent. But can be But can be fulminant fulminant & & fatal!fatal!
•Severity is proportional to the loadSeverity is proportional to the load
•In the 1In the 1
stst
w of ingesting infected meat, a person may be w of ingesting infected meat, a person may be
asymptomatic/have abdo. discomfort, NVDasymptomatic/have abdo. discomfort, NVD
•2-8w later, as larvae migrate into tissues, F, myalgia, 2-8w later, as larvae migrate into tissues, F, myalgia,
periorbital edema, urticaria, conjunctival & subungual periorbital edema, urticaria, conjunctival & subungual hge. hge.
may developmay develop
•Larvae live in tissues for years; calcification of larvae Larvae live in tissues for years; calcification of larvae
occurs within 6-24mo (on X-ray)occurs within 6-24mo (on X-ray)
•In severe inf. : myocarditis, neuropathy, pneumonitis can In severe inf. : myocarditis, neuropathy, pneumonitis can
follow in 1-2 mo follow in 1-2 mo
Mostly Mostly inapparent. inapparent. But can be But can be fulminant fulminant & & fatal!fatal!
•Severity is proportional to the loadSeverity is proportional to the load
•In the 1In the 1
stst
w of ingesting infected meat, a person may be w of ingesting infected meat, a person may be
asymptomatic/have abdo. discomfort, NVDasymptomatic/have abdo. discomfort, NVD
•2-8w later, as larvae migrate into tissues, F, myalgia, 2-8w later, as larvae migrate into tissues, F, myalgia,
periorbital edema, urticaria, conjunctival & subungual periorbital edema, urticaria, conjunctival & subungual hge. hge.
may developmay develop
•Larvae live in tissues for years; calcification of larvae Larvae live in tissues for years; calcification of larvae
occurs within 6-24mo (on X-ray)occurs within 6-24mo (on X-ray)
•In severe inf. : myocarditis, neuropathy, pneumonitis can In severe inf. : myocarditis, neuropathy, pneumonitis can
follow in 1-2 mo follow in 1-2 mo
DIAGNOSISDIAGNOSIS
•Eosinophilia (70%), SS, dietary h/of, suggestiveEosinophilia (70%), SS, dietary h/of, suggestive
•Raised muscle enzymes (CPK, LDH)Raised muscle enzymes (CPK, LDH)
•Encapsulated larvae in skeletal muscle biopsy (deltoid & Encapsulated larvae in skeletal muscle biopsy (deltoid &
gastrocnemius) 2w after infectiongastrocnemius) 2w after infection
•Serologic tests are available (CDC). S. antibody rarely Serologic tests are available (CDC). S. antibody rarely
positive before 2positive before 2
ndnd
w of illness. Testing paired w of illness. Testing paired acute & acute &
convalescent serum specimens usually is convalescent serum specimens usually is diagnosticdiagnostic
•Eosinophilia (70%), SS, dietary h/of, suggestiveEosinophilia (70%), SS, dietary h/of, suggestive
•Raised muscle enzymes (CPK, LDH)Raised muscle enzymes (CPK, LDH)
•Encapsulated larvae in skeletal muscle biopsy (deltoid & Encapsulated larvae in skeletal muscle biopsy (deltoid &
gastrocnemius) 2w after infectiongastrocnemius) 2w after infection
•Serologic tests are available (CDC). S. antibody rarely Serologic tests are available (CDC). S. antibody rarely
positive before 2positive before 2
ndnd
w of illness. Testing paired w of illness. Testing paired acute & acute &
convalescent serum specimens usually is convalescent serum specimens usually is diagnosticdiagnostic
TREATMENTTREATMENT
•Mebendazole/albendazole effective. Neither drug is very Mebendazole/albendazole effective. Neither drug is very
effective for effective for TT larvae in muscles larvae in muscles
•Steroids with anthelmintic often is recommended when SS Steroids with anthelmintic often is recommended when SS
are severe. Steroids suppress inflam. & can be are severe. Steroids suppress inflam. & can be
lifesaving when CNS or heart is involvedlifesaving when CNS or heart is involved
•Mebendazole/albendazole effective. Neither drug is very Mebendazole/albendazole effective. Neither drug is very
effective for effective for TT larvae in muscles larvae in muscles
•Steroids with anthelmintic often is recommended when SS Steroids with anthelmintic often is recommended when SS
are severe. Steroids suppress inflam. & can be are severe. Steroids suppress inflam. & can be
lifesaving when CNS or heart is involvedlifesaving when CNS or heart is involved
CONTROL MEASURESCONTROL MEASURES
•Transmission to pigs by not feeding pigs garbage Transmission to pigs by not feeding pigs garbage
& by effective rat control& by effective rat control
•Cook pork thoroughly (meat is no longer pink). Cook pork thoroughly (meat is no longer pink).
Freezing pork at -23°C x10d kills larvaeFreezing pork at -23°C x10d kills larvae
•People who have ingested contaminated meat People who have ingested contaminated meat
should be Rx with anthelminthshould be Rx with anthelminth
•Transmission to pigs by not feeding pigs garbage Transmission to pigs by not feeding pigs garbage
& by effective rat control& by effective rat control
•Cook pork thoroughly (meat is no longer pink). Cook pork thoroughly (meat is no longer pink).
Freezing pork at -23°C x10d kills larvaeFreezing pork at -23°C x10d kills larvae
•People who have ingested contaminated meat People who have ingested contaminated meat
should be Rx with anthelminthshould be Rx with anthelminth
TS larvae in skeletal muscle
Trichinosis. Trichinosis.
Striking edema of Striking edema of
face. A h/of eating face. A h/of eating
of poorly cooked of poorly cooked
"hogs head“. "hogs head“.
Periorbital edema Periorbital edema
& conjunctivitis & conjunctivitis
are commonly are commonly
seenseen
Striking edema of Striking edema of
face. A h/of eating face. A h/of eating
of poorly cooked of poorly cooked
"hogs head“. "hogs head“.
Periorbital edema Periorbital edema
& conjunctivitis & conjunctivitis
are commonly are commonly
seenseen
Trichinosis. Striking edema of feet of the same pt.Trichinosis. Striking edema of feet of the same pt.
Trichinosis. Periorbital swelling with discharge, muscle pain, & 28% Trichinosis. Periorbital swelling with discharge, muscle pain, & 28%
eosinophilseosinophils
eosinophilseosinophils
Trichinosis. Splinter hge. under nailsTrichinosis. Splinter hge. under nails
(Strongyloides (Strongyloides
stercoralis)stercoralis)
Strongyloidiasis Strongyloidiasis
stercoralis)stercoralis)
Strongyloidiasis Strongyloidiasis
Larva currensLarva currens
EPIDEMIOLOGYEPIDEMIOLOGY
•A A nematode. nematode. Endemic in tropics, subtropicsEndemic in tropics, subtropics
•Humans principal Humans principal reservoirsreservoirs. Also dogs, cats, other animals. Also dogs, cats, other animals
•Transmission Transmission by penetration of skin by filariform larvae by penetration of skin by filariform larvae
(soil/autoinfection) (soil/autoinfection) ÞÞ migrate to lungs migrate to lungs ÞÞ ascend to be ascend to be
swallowed swallowed ÞÞ mature in wall of duodenum, jejunum. mature in wall of duodenum, jejunum.
Some mature in colon to autoinfectSome mature in colon to autoinfect
•Adult females lay eggs Adult females lay eggs ÞÞ free-living rhabditiform larvae on free-living rhabditiform larvae on
passing in feces. Autoinfection may make pt. infected passing in feces. Autoinfection may make pt. infected
for decades. In immunocompromised pts., for decades. In immunocompromised pts.,
autoinfection may cause dissemination autoinfection may cause dissemination (hyperinfection)(hyperinfection)
•A A nematode. nematode. Endemic in tropics, subtropicsEndemic in tropics, subtropics
•Humans principal Humans principal reservoirsreservoirs. Also dogs, cats, other animals. Also dogs, cats, other animals
•Transmission Transmission by penetration of skin by filariform larvae by penetration of skin by filariform larvae
(soil/autoinfection) (soil/autoinfection) ÞÞ migrate to lungs migrate to lungs ÞÞ ascend to be ascend to be
swallowed swallowed ÞÞ mature in wall of duodenum, jejunum. mature in wall of duodenum, jejunum.
Some mature in colon to autoinfectSome mature in colon to autoinfect
•Adult females lay eggs Adult females lay eggs ÞÞ free-living rhabditiform larvae on free-living rhabditiform larvae on
passing in feces. Autoinfection may make pt. infected passing in feces. Autoinfection may make pt. infected
for decades. In immunocompromised pts., for decades. In immunocompromised pts.,
autoinfection may cause dissemination autoinfection may cause dissemination (hyperinfection)(hyperinfection)
Life cycleLife cycle
It is complex among all helminths:It is complex among all helminths:
•Alternate free-living & sexual cyclesAlternate free-living & sexual cycles
•Potential for autoinfection & multiplication within the hostPotential for autoinfection & multiplication within the host
•2 LC:2 LC:
It is complex among all helminths:It is complex among all helminths:
•Alternate free-living & sexual cyclesAlternate free-living & sexual cycles
•Potential for autoinfection & multiplication within the hostPotential for autoinfection & multiplication within the host
•2 LC:2 LC:
Free-living cycleFree-living cycle
•Rhabditiform larvae passed in stool (1) can either molt Rhabditiform larvae passed in stool (1) can either molt
x2 to become infective filariform (direct development) x2 to become infective filariform (direct development)
(6) or molt x4 & become free-living adult males & F (2) (6) or molt x4 & become free-living adult males & F (2)
that mate to produce eggs (3) from which rhabditiform that mate to produce eggs (3) from which rhabditiform
larvae hatch (4) which in turn can either develop (5) larvae hatch (4) which in turn can either develop (5)
into a new generation of free-living adults or into into a new generation of free-living adults or into
infective filariform larvae (6)infective filariform larvae (6)
•Filariform larvae penetrate human skin to initiate parasitic Filariform larvae penetrate human skin to initiate parasitic
cyclecycle
•Rhabditiform larvae passed in stool (1) can either molt Rhabditiform larvae passed in stool (1) can either molt
x2 to become infective filariform (direct development) x2 to become infective filariform (direct development)
(6) or molt x4 & become free-living adult males & F (2) (6) or molt x4 & become free-living adult males & F (2)
that mate to produce eggs (3) from which rhabditiform that mate to produce eggs (3) from which rhabditiform
larvae hatch (4) which in turn can either develop (5) larvae hatch (4) which in turn can either develop (5)
into a new generation of free-living adults or into into a new generation of free-living adults or into
infective filariform larvae (6)infective filariform larvae (6)
•Filariform larvae penetrate human skin to initiate parasitic Filariform larvae penetrate human skin to initiate parasitic
cyclecycle
Parasitic cycleParasitic cycle
•Filariform l. in soil penetrate skin (6) Filariform l. in soil penetrate skin (6) ÞÞ lungs (alveoli) lungs (alveoli) ÞÞ
ascend to be swallowed ascend to be swallowed ÞÞ reach small gut (7) reach small gut (7) ÞÞ molt molt
x2 & become adults (8). Females live threaded in gut x2 & become adults (8). Females live threaded in gut
epith. & by epith. & by parthenogenesisparthenogenesis produce eggs (9) produce eggs (9) ÞÞ
rhabditiform l.: can either be passed in stool (1) or rhabditiform l.: can either be passed in stool (1) or
cause cause autoinfectionautoinfection (10) (10)
•In In autoinfectionautoinfection, rhabditiform become filariform , rhabditiform become filariform ÞÞ
penetrate either gut mucosa (internal autoinfection) penetrate either gut mucosa (internal autoinfection) or or
perianal area (external autoinfection); in either perianal area (external autoinfection); in either case, the case, the
filariform l. may follow the pulmonary route; filariform l. may follow the pulmonary route; or may or may
disseminate widelydisseminate widely
•Autoinfection explains persistent infections for decades & Autoinfection explains persistent infections for decades &
of hyperinfectionsof hyperinfections
•Filariform l. in soil penetrate skin (6) Filariform l. in soil penetrate skin (6) ÞÞ lungs (alveoli) lungs (alveoli) ÞÞ
ascend to be swallowed ascend to be swallowed ÞÞ reach small gut (7) reach small gut (7) ÞÞ molt molt
x2 & become adults (8). Females live threaded in gut x2 & become adults (8). Females live threaded in gut
epith. & by epith. & by parthenogenesisparthenogenesis produce eggs (9) produce eggs (9) ÞÞ
rhabditiform l.: can either be passed in stool (1) or rhabditiform l.: can either be passed in stool (1) or
cause cause autoinfectionautoinfection (10) (10)
•In In autoinfectionautoinfection, rhabditiform become filariform , rhabditiform become filariform ÞÞ
penetrate either gut mucosa (internal autoinfection) penetrate either gut mucosa (internal autoinfection) or or
perianal area (external autoinfection); in either perianal area (external autoinfection); in either case, the case, the
filariform l. may follow the pulmonary route; filariform l. may follow the pulmonary route; or may or may
disseminate widelydisseminate widely
•Autoinfection explains persistent infections for decades & Autoinfection explains persistent infections for decades &
of hyperinfectionsof hyperinfections
CL. MANIFESTATIONSCL. MANIFESTATIONS
•AsymptomaticAsymptomatic. . Eosinophilia may be the only featureEosinophilia may be the only feature
•Consider it in an endemic area if eosinophilia (>500/µL) Consider it in an endemic area if eosinophilia (>500/µL)
w/o obvious causew/o obvious cause
•Larval migration: Larval migration:
a) a) in lungs: pn., bloody cough (mucoid & voluminous)in lungs: pn., bloody cough (mucoid & voluminous)
b)b) from stool: itchy migrating, serpentine rash from stool: itchy migrating, serpentine rash
around as tracks (around as tracks (larva currens)larva currens)
•Intestinal phase: Intestinal phase: AP, distention, VD, hyperinfection, AP, distention, VD, hyperinfection,
septicemia/meningitis by enteric gram-ve bacilli (more septicemia/meningitis by enteric gram-ve bacilli (more
in immunocompromised, less in Mn, alcoholic, HIV)in immunocompromised, less in Mn, alcoholic, HIV)
•AsymptomaticAsymptomatic. . Eosinophilia may be the only featureEosinophilia may be the only feature
•Consider it in an endemic area if eosinophilia (>500/µL) Consider it in an endemic area if eosinophilia (>500/µL)
w/o obvious causew/o obvious cause
•Larval migration: Larval migration:
a) a) in lungs: pn., bloody cough (mucoid & voluminous)in lungs: pn., bloody cough (mucoid & voluminous)
b)b) from stool: itchy migrating, serpentine rash from stool: itchy migrating, serpentine rash
around as tracks (around as tracks (larva currens)larva currens)
•Intestinal phase: Intestinal phase: AP, distention, VD, hyperinfection, AP, distention, VD, hyperinfection,
septicemia/meningitis by enteric gram-ve bacilli (more septicemia/meningitis by enteric gram-ve bacilli (more
in immunocompromised, less in Mn, alcoholic, HIV)in immunocompromised, less in Mn, alcoholic, HIV)
ComplicationsComplications
•Dissemination (hyperinfection)Dissemination (hyperinfection)
•Diffuse pulmonary infiltrates (Loeffler S)Diffuse pulmonary infiltrates (Loeffler S)
•Septicemia, meningitis by enteric gram-vesSepticemia, meningitis by enteric gram-ves
•Dissemination (hyperinfection)Dissemination (hyperinfection)
•Diffuse pulmonary infiltrates (Loeffler S)Diffuse pulmonary infiltrates (Loeffler S)
•Septicemia, meningitis by enteric gram-vesSepticemia, meningitis by enteric gram-ves
DIAGNOSISDIAGNOSIS
•Stool: Stool: typical larvae; several fresh samples needed. Concn. typical larvae; several fresh samples needed. Concn.
procedure may be requiredprocedure may be required
•Duodenal aspirate by Duodenal aspirate by Entero-Test/ endoscopic aspirate Entero-Test/ endoscopic aspirate
may show larvaemay show larvae
•SerodiagnosisSerodiagnosis seem to be most sensitive but do not DD seem to be most sensitive but do not DD
past & current infx. & false-negative occurspast & current infx. & false-negative occurs
•Sputum: Sputum: larvae can be found in larvae can be found in hyperinfectionhyperinfection
•Eosinophilia Eosinophilia (>500/µL) is common(>500/µL) is common
•Stool: Stool: typical larvae; several fresh samples needed. Concn. typical larvae; several fresh samples needed. Concn.
procedure may be requiredprocedure may be required
•Duodenal aspirate by Duodenal aspirate by Entero-Test/ endoscopic aspirate Entero-Test/ endoscopic aspirate
may show larvaemay show larvae
•SerodiagnosisSerodiagnosis seem to be most sensitive but do not DD seem to be most sensitive but do not DD
past & current infx. & false-negative occurspast & current infx. & false-negative occurs
•Sputum: Sputum: larvae can be found in larvae can be found in hyperinfectionhyperinfection
•Eosinophilia Eosinophilia (>500/µL) is common(>500/µL) is common
RxRx
•Ivermectin/thiabendazole is mostly curative, not in Ivermectin/thiabendazole is mostly curative, not in
pregnancy (for heavy inf. ivermectin is DoC)pregnancy (for heavy inf. ivermectin is DoC)
•Rx may need repetition or prolonged in hyperinfection or Rx may need repetition or prolonged in hyperinfection or
in immunocompromisedin immunocompromised
•Relapses are treated similarlyRelapses are treated similarly
•Ivermectin/thiabendazole is mostly curative, not in Ivermectin/thiabendazole is mostly curative, not in
pregnancy (for heavy inf. ivermectin is DoC)pregnancy (for heavy inf. ivermectin is DoC)
•Rx may need repetition or prolonged in hyperinfection or Rx may need repetition or prolonged in hyperinfection or
in immunocompromisedin immunocompromised
•Relapses are treated similarlyRelapses are treated similarly
CONTROL MEASURESCONTROL MEASURES
•Safe disposal of human wasteSafe disposal of human waste
•Education about infection through bare skin is importantEducation about infection through bare skin is important
•Immunocompromized & pt. in endemic area: exclude it Immunocompromized & pt. in endemic area: exclude it
before immunosuppressive Rx. For immediate before immunosuppressive Rx. For immediate
immunosuppressive Rx: empiric Rx must be consideredimmunosuppressive Rx: empiric Rx must be considered
•Safe disposal of human wasteSafe disposal of human waste
•Education about infection through bare skin is importantEducation about infection through bare skin is important
•Immunocompromized & pt. in endemic area: exclude it Immunocompromized & pt. in endemic area: exclude it
before immunosuppressive Rx. For immediate before immunosuppressive Rx. For immediate
immunosuppressive Rx: empiric Rx must be consideredimmunosuppressive Rx: empiric Rx must be considered
Peculiarities of Peculiarities of S stercoralisS stercoralis
•Can lead both free-living & parasitic cyclesCan lead both free-living & parasitic cycles
•Females can produce eggs by parthenogenesisFemales can produce eggs by parthenogenesis
•Transmission by larvaeTransmission by larvae
•Penetrate intact skinPenetrate intact skin
•Autoinfection: maintain for decadesAutoinfection: maintain for decades
•HyperinfectionHyperinfection
•Can lead both free-living & parasitic cyclesCan lead both free-living & parasitic cycles
•Females can produce eggs by parthenogenesisFemales can produce eggs by parthenogenesis
•Transmission by larvaeTransmission by larvae
•Penetrate intact skinPenetrate intact skin
•Autoinfection: maintain for decadesAutoinfection: maintain for decades
•HyperinfectionHyperinfection
S stercoralisS stercoralis larvae (low-power magnification) larvae (low-power magnification)
S stercoralisS stercoralis larvae (oil-immersion magnification) larvae (oil-immersion magnification)
Trichuris
trichiuria
(whipworm)
trichiuria
(whipworm)
•Whipworm is 3Whipworm is 3
rdrd
commonest nematode: more in areas commonest nematode: more in areas
where human feces is used as manure or of poor where human feces is used as manure or of poor
sanitation. Fecal-oral transmissionsanitation. Fecal-oral transmission
•Worldwide, more in tropics, among children. 1 billion casesWorldwide, more in tropics, among children. 1 billion cases
CF:CF:
•Light/heavy infections. May be Light/heavy infections. May be asymptaticasymptatic
•Dysenteric stools (may be chr., mimicking IBD), Dysenteric stools (may be chr., mimicking IBD), tenesmus, tenesmus,
AP, distention, AP, distention, rectal prolapse, rectal prolapse, appendicitis, urticaria, appendicitis, urticaria,
severe anemia, FTT, impaired cognitionsevere anemia, FTT, impaired cognition
rdrd
commonest nematode: more in areas commonest nematode: more in areas
where human feces is used as manure or of poor where human feces is used as manure or of poor
sanitation. Fecal-oral transmissionsanitation. Fecal-oral transmission
•Worldwide, more in tropics, among children. 1 billion casesWorldwide, more in tropics, among children. 1 billion cases
CF:CF:
•Light/heavy infections. May be Light/heavy infections. May be asymptaticasymptatic
•Dysenteric stools (may be chr., mimicking IBD), Dysenteric stools (may be chr., mimicking IBD), tenesmus, tenesmus,
AP, distention, AP, distention, rectal prolapse, rectal prolapse, appendicitis, urticaria, appendicitis, urticaria,
severe anemia, FTT, impaired cognitionsevere anemia, FTT, impaired cognition
LCLC
•Immature eggs are passed in stoolImmature eggs are passed in stoolÞÞ develop in soil into 2- develop in soil into 2-
cell stagecell stageÞÞ embryonate embryonateÞÞ infective (15-30d) infective (15-30d)ÞÞ ingestion ingestion
(soil, hands or food)(soil, hands or food)ÞÞ larvae hatch in small gut larvae hatch in small gutÞÞ mature as mature as
adults in colonadults in colon
•Adults (4cm) live in cecum&ascending colon with anterior Adults (4cm) live in cecum&ascending colon with anterior
portions threaded into mucosaportions threaded into mucosa
•Females oviposit 60-70d after infection&shed 3,000-20,000 Females oviposit 60-70d after infection&shed 3,000-20,000
eggs/deggs/d
•Live about 1 yLive about 1 y
•Immature eggs are passed in stoolImmature eggs are passed in stoolÞÞ develop in soil into 2- develop in soil into 2-
cell stagecell stageÞÞ embryonate embryonateÞÞ infective (15-30d) infective (15-30d)ÞÞ ingestion ingestion
(soil, hands or food)(soil, hands or food)ÞÞ larvae hatch in small gut larvae hatch in small gutÞÞ mature as mature as
adults in colonadults in colon
•Adults (4cm) live in cecum&ascending colon with anterior Adults (4cm) live in cecum&ascending colon with anterior
portions threaded into mucosaportions threaded into mucosa
•Females oviposit 60-70d after infection&shed 3,000-20,000 Females oviposit 60-70d after infection&shed 3,000-20,000
eggs/deggs/d
•Live about 1 yLive about 1 y
DiagnosisDiagnosis
•Eggs in stool: concn. Eggs in stool: concn.
method better method better
•EndoscopyEndoscopy
•Eosinophilia, IDAEosinophilia, IDA
TreatmentTreatment
•Albendazole/mebendazole are DoCAlbendazole/mebendazole are DoC
•Repeat stool exam Repeat stool exam
•Iron supplements for anemiaIron supplements for anemia
•Eggs in stool: concn. Eggs in stool: concn.
method better method better
•EndoscopyEndoscopy
•Eosinophilia, IDAEosinophilia, IDA
TreatmentTreatment
•Albendazole/mebendazole are DoCAlbendazole/mebendazole are DoC
•Repeat stool exam Repeat stool exam
•Iron supplements for anemiaIron supplements for anemia
Prevention & ControlPrevention & Control
•Avoid ingesting soilAvoid ingesting soil
•Wash hands before handling foodWash hands before handling food
•Wash, peel, or cook all raw vegetables before Wash, peel, or cook all raw vegetables before
eating, particularly those that have been grown eating, particularly those that have been grown
in soil that has been fertilized with manure.in soil that has been fertilized with manure.
•Avoid ingesting soilAvoid ingesting soil
•Wash hands before handling foodWash hands before handling food
•Wash, peel, or cook all raw vegetables before Wash, peel, or cook all raw vegetables before
eating, particularly those that have been grown eating, particularly those that have been grown
in soil that has been fertilized with manure.in soil that has been fertilized with manure.
Echinococcus Echinococcus
granulosus/ granulosus/
E. multilocularisE. multilocularis
(Hydatid disease: dwarf (Hydatid disease: dwarf
tapeworm)tapeworm)
granulosus/ granulosus/
E. multilocularisE. multilocularis
(Hydatid disease: dwarf (Hydatid disease: dwarf
tapeworm)tapeworm)
•Human echinococcosis (hydatidosis, or hydatid Human echinococcosis (hydatidosis, or hydatid
disease/cyst) is c/by larval stages of disease/cyst) is c/by larval stages of EchinococcusEchinococcus
•E granulosusE granulosus causes cystic echinococcosis (CE): causes cystic echinococcosis (CE):
most frequently encounteredmost frequently encountered
•E multilocularisE multilocularis causes alveolar echinococcosis (AE) causes alveolar echinococcosis (AE)
•E vogeliE vogeli causes polycystic echinococcosis causes polycystic echinococcosis
•E oligarthrusE oligarthrus is extremely rare is extremely rare
disease/cyst) is c/by larval stages of disease/cyst) is c/by larval stages of EchinococcusEchinococcus
•E granulosusE granulosus causes cystic echinococcosis (CE): causes cystic echinococcosis (CE):
most frequently encounteredmost frequently encountered
•E multilocularisE multilocularis causes alveolar echinococcosis (AE) causes alveolar echinococcosis (AE)
•E vogeliE vogeli causes polycystic echinococcosis causes polycystic echinococcosis
•E oligarthrusE oligarthrus is extremely rare is extremely rare
LCLC
•Adult Adult E granulosusE granulosus (3-6mm) resides in small gut of (3-6mm) resides in small gut of
definitive hosts (dogs or other canids). Gravid proglottids definitive hosts (dogs or other canids). Gravid proglottids
release eggsrelease eggsÞÞ in feces in fecesÞÞ ingested by intermediate host ingested by intermediate host
(sheep, goat, swine, cattle, camel)(sheep, goat, swine, cattle, camel)ÞÞ oncosphere hatches oncosphere hatches
in small gutin small gutÞÞ penetrates gut wall penetrates gut wallÞÞ migrates into organs migrates into organs
(liver, lungs)(liver, lungs)ÞÞ cyst (enlarges gradually) producing cyst (enlarges gradually) producing
protoscolices&daughter cysts that fill the cystprotoscolices&daughter cysts that fill the cyst
•Definitive host is infected by ingesting the cyst of Definitive host is infected by ingesting the cyst of
intermediate hostintermediate hostÞÞ protoscolices evaginate gut mucosa protoscolices evaginate gut mucosaÞÞ
develop as adults (32-80d)develop as adults (32-80d)
•LC of LC of E. multilocularisE. multilocularis is similar; some differences is similar; some differences
•Adult Adult E granulosusE granulosus (3-6mm) resides in small gut of (3-6mm) resides in small gut of
definitive hosts (dogs or other canids). Gravid proglottids definitive hosts (dogs or other canids). Gravid proglottids
release eggsrelease eggsÞÞ in feces in fecesÞÞ ingested by intermediate host ingested by intermediate host
(sheep, goat, swine, cattle, camel)(sheep, goat, swine, cattle, camel)ÞÞ oncosphere hatches oncosphere hatches
in small gutin small gutÞÞ penetrates gut wall penetrates gut wallÞÞ migrates into organs migrates into organs
(liver, lungs)(liver, lungs)ÞÞ cyst (enlarges gradually) producing cyst (enlarges gradually) producing
protoscolices&daughter cysts that fill the cystprotoscolices&daughter cysts that fill the cyst
•Definitive host is infected by ingesting the cyst of Definitive host is infected by ingesting the cyst of
intermediate hostintermediate hostÞÞ protoscolices evaginate gut mucosa protoscolices evaginate gut mucosaÞÞ
develop as adults (32-80d)develop as adults (32-80d)
•LC of LC of E. multilocularisE. multilocularis is similar; some differences is similar; some differences
•Cystic echinocccosis (CE):Cystic echinocccosis (CE): or hydatid D, is c/by larvae of or hydatid D, is c/by larvae of E E
granulosusgranulosus, found in dogs (definitive host)&sheep, cattle, , found in dogs (definitive host)&sheep, cattle,
goats, pigs (intermediate H). Most infections in humans goats, pigs (intermediate H). Most infections in humans
are are asymptomaticasymptomatic, CE causes harmful, slowly enlarging , CE causes harmful, slowly enlarging
cysts in liver, lungs, other organs (neglected for years)cysts in liver, lungs, other organs (neglected for years)
•Alveolar echinococcosis (AE):Alveolar echinococcosis (AE): by larvae of by larvae of E multilocularisE multilocularis, ,
smaller, found in foxes, coyotes,&dogs (definitive H). Small smaller, found in foxes, coyotes,&dogs (definitive H). Small
rodents are intermediate Hrodents are intermediate H.. Although cases of AE in Although cases of AE in
animals in endemic areas are relatively common, human animals in endemic areas are relatively common, human
cases are rare. AE poses a much greater health threat than cases are rare. AE poses a much greater health threat than
CE: parasitic tumors in liver, lungs, brain, other organs; can CE: parasitic tumors in liver, lungs, brain, other organs; can
be fatalbe fatal
granulosusgranulosus, found in dogs (definitive host)&sheep, cattle, , found in dogs (definitive host)&sheep, cattle,
goats, pigs (intermediate H). Most infections in humans goats, pigs (intermediate H). Most infections in humans
are are asymptomaticasymptomatic, CE causes harmful, slowly enlarging , CE causes harmful, slowly enlarging
cysts in liver, lungs, other organs (neglected for years)cysts in liver, lungs, other organs (neglected for years)
•Alveolar echinococcosis (AE):Alveolar echinococcosis (AE): by larvae of by larvae of E multilocularisE multilocularis, ,
smaller, found in foxes, coyotes,&dogs (definitive H). Small smaller, found in foxes, coyotes,&dogs (definitive H). Small
rodents are intermediate Hrodents are intermediate H.. Although cases of AE in Although cases of AE in
animals in endemic areas are relatively common, human animals in endemic areas are relatively common, human
cases are rare. AE poses a much greater health threat than cases are rare. AE poses a much greater health threat than
CE: parasitic tumors in liver, lungs, brain, other organs; can CE: parasitic tumors in liver, lungs, brain, other organs; can
be fatalbe fatal
•CECE is found in Africa, Europe, Asia, ME, C.&S. is found in Africa, Europe, Asia, ME, C.&S.
Americas. Transmitted to dogs when they ingest Americas. Transmitted to dogs when they ingest
organs containing HC&develop adult tapeworms in organs containing HC&develop adult tapeworms in
gut. Infected dogs shed eggs. Sheep, cattle, goats, gut. Infected dogs shed eggs. Sheep, cattle, goats,
pigs ingest eggs that hatch&develop into cysts in pigs ingest eggs that hatch&develop into cysts in
organs. The commonest transmission to humans is organs. The commonest transmission to humans is
by accidental consumption of soil, water, or food by accidental consumption of soil, water, or food
that has been contaminated by feces of an infected that has been contaminated by feces of an infected
dog. Eggs in soil are viable for a yeardog. Eggs in soil are viable for a year
•Most commonly found in people who raise sheep, Most commonly found in people who raise sheep,
(intermediate H). Working dogs when allowed to (intermediate H). Working dogs when allowed to
eat the offal of infected sheep spread the diseaseeat the offal of infected sheep spread the disease
Americas. Transmitted to dogs when they ingest Americas. Transmitted to dogs when they ingest
organs containing HC&develop adult tapeworms in organs containing HC&develop adult tapeworms in
gut. Infected dogs shed eggs. Sheep, cattle, goats, gut. Infected dogs shed eggs. Sheep, cattle, goats,
pigs ingest eggs that hatch&develop into cysts in pigs ingest eggs that hatch&develop into cysts in
organs. The commonest transmission to humans is organs. The commonest transmission to humans is
by accidental consumption of soil, water, or food by accidental consumption of soil, water, or food
that has been contaminated by feces of an infected that has been contaminated by feces of an infected
dog. Eggs in soil are viable for a yeardog. Eggs in soil are viable for a year
•Most commonly found in people who raise sheep, Most commonly found in people who raise sheep,
(intermediate H). Working dogs when allowed to (intermediate H). Working dogs when allowed to
eat the offal of infected sheep spread the diseaseeat the offal of infected sheep spread the disease
L to R: E granulosus adult. Close-up of the scolex of E.
granulosus. One of the suckers is clearly visible, as is the ring of
rostellar hooks
granulosus. One of the suckers is clearly visible, as is the ring of
rostellar hooks
CFCF
•CE often remains CE often remains asymptomatic asymptomatic until grow big until grow big
(several years) to cause discomfort, pain, nausea, (several years) to cause discomfort, pain, nausea,
vomiting. SS typically depends on the locationvomiting. SS typically depends on the location
•Mainly found in liver&lungs but can appear in Mainly found in liver&lungs but can appear in
others. Cyst if ruptures (trauma) may cause mild to others. Cyst if ruptures (trauma) may cause mild to
severe anaphylactic reactions, even death, as a severe anaphylactic reactions, even death, as a
result of the release of cystic fluidresult of the release of cystic fluid
•CE often remains CE often remains asymptomatic asymptomatic until grow big until grow big
(several years) to cause discomfort, pain, nausea, (several years) to cause discomfort, pain, nausea,
vomiting. SS typically depends on the locationvomiting. SS typically depends on the location
•Mainly found in liver&lungs but can appear in Mainly found in liver&lungs but can appear in
others. Cyst if ruptures (trauma) may cause mild to others. Cyst if ruptures (trauma) may cause mild to
severe anaphylactic reactions, even death, as a severe anaphylactic reactions, even death, as a
result of the release of cystic fluidresult of the release of cystic fluid
DxDx
•Presence of cyst-like mass with h/of exposure to Presence of cyst-like mass with h/of exposure to
sheepdogs in an endemic suggests Dxsheepdogs in an endemic suggests Dx
•Imaging: CT, USG, MRIs are usefulImaging: CT, USG, MRIs are useful
•After detection, serologic tests to confirmAfter detection, serologic tests to confirm
•Presence of cyst-like mass with h/of exposure to Presence of cyst-like mass with h/of exposure to
sheepdogs in an endemic suggests Dxsheepdogs in an endemic suggests Dx
•Imaging: CT, USG, MRIs are usefulImaging: CT, USG, MRIs are useful
•After detection, serologic tests to confirmAfter detection, serologic tests to confirm
RxRx
•Surgery was only Rx. Chemotherapy, cyst puncture, Surgery was only Rx. Chemotherapy, cyst puncture,
& PAIR (percutaneous aspiration, injection of & PAIR (percutaneous aspiration, injection of
chemicals & reaspiration) have replaced surgerychemicals & reaspiration) have replaced surgery
•But surgery remains the most effective Rx to But surgery remains the most effective Rx to
remove it for complete cureremove it for complete cure
•Silent cysts often go away without RxSilent cysts often go away without Rx
•Surgery was only Rx. Chemotherapy, cyst puncture, Surgery was only Rx. Chemotherapy, cyst puncture,
& PAIR (percutaneous aspiration, injection of & PAIR (percutaneous aspiration, injection of
chemicals & reaspiration) have replaced surgerychemicals & reaspiration) have replaced surgery
•But surgery remains the most effective Rx to But surgery remains the most effective Rx to
remove it for complete cureremove it for complete cure
•Silent cysts often go away without RxSilent cysts often go away without Rx
PreventionPrevention
•Limiting areas for dog. Prevent it eating infected Limiting areas for dog. Prevent it eating infected
meat, carcasses of infected sheepmeat, carcasses of infected sheep
•Control stray dog. Wash hands after touching dogs, Control stray dog. Wash hands after touching dogs,
before handling foodbefore handling food
•Restrict home slaughter of livestockRestrict home slaughter of livestock
•Do not eat food/water ?contaminated by dog fecesDo not eat food/water ?contaminated by dog feces
•Teach children washing handsTeach children washing hands
•Limiting areas for dog. Prevent it eating infected Limiting areas for dog. Prevent it eating infected
meat, carcasses of infected sheepmeat, carcasses of infected sheep
•Control stray dog. Wash hands after touching dogs, Control stray dog. Wash hands after touching dogs,
before handling foodbefore handling food
•Restrict home slaughter of livestockRestrict home slaughter of livestock
•Do not eat food/water ?contaminated by dog fecesDo not eat food/water ?contaminated by dog feces
•Teach children washing handsTeach children washing hands
ANTI-HELMINTHICS ANTI-HELMINTHICS (vermicide, vermifuge)(vermicide, vermifuge)
•MEBENDAZOLE. blocks glucose uptake & depletes MEBENDAZOLE. blocks glucose uptake & depletes
glycogen. Acts against: glycogen. Acts against: AL, EV, AD,TT, AL, EV, AD,TT, Tapeworm, Hydatid Tapeworm, Hydatid
cyst, Neurocysticercosiscyst, Neurocysticercosis
• SE: NVD, allergy, loss of hair, granulocytopenia. Dose: SE: NVD, allergy, loss of hair, granulocytopenia. Dose:
100mg BD x 3 d. Enterobius:100mg once, repeated after 100mg BD x 3 d. Enterobius:100mg once, repeated after
2w2w
•Albendazole: congener of mebendazole. single dose. Acts Albendazole: congener of mebendazole. single dose. Acts
against: against: AL, EV, AD,TT, AL, EV, AD,TT, Tapeworm, Hydatid D, Tapeworm, Hydatid D,
Neurocysticercosis, filariasisNeurocysticercosis, filariasis
•SE: well tolerated, Few had dizziness .Prolonged use HA, SE: well tolerated, Few had dizziness .Prolonged use HA,
F, alopecia, jaundice, neutropeniaF, alopecia, jaundice, neutropenia
•MEBENDAZOLE. blocks glucose uptake & depletes MEBENDAZOLE. blocks glucose uptake & depletes
glycogen. Acts against: glycogen. Acts against: AL, EV, AD,TT, AL, EV, AD,TT, Tapeworm, Hydatid Tapeworm, Hydatid
cyst, Neurocysticercosiscyst, Neurocysticercosis
• SE: NVD, allergy, loss of hair, granulocytopenia. Dose: SE: NVD, allergy, loss of hair, granulocytopenia. Dose:
100mg BD x 3 d. Enterobius:100mg once, repeated after 100mg BD x 3 d. Enterobius:100mg once, repeated after
2w2w
•Albendazole: congener of mebendazole. single dose. Acts Albendazole: congener of mebendazole. single dose. Acts
against: against: AL, EV, AD,TT, AL, EV, AD,TT, Tapeworm, Hydatid D, Tapeworm, Hydatid D,
Neurocysticercosis, filariasisNeurocysticercosis, filariasis
•SE: well tolerated, Few had dizziness .Prolonged use HA, SE: well tolerated, Few had dizziness .Prolonged use HA,
F, alopecia, jaundice, neutropeniaF, alopecia, jaundice, neutropenia
•Pyrantel palmoate. Efficacy against AL,, EV, AD, is Pyrantel palmoate. Efficacy against AL,, EV, AD, is
high, comparable to mebendazole. Causes spastic high, comparable to mebendazole. Causes spastic
paralysis. Remarkably free of SE, tasteless, non paralysis. Remarkably free of SE, tasteless, non
irritant, abnormal migration of worms is not seen.irritant, abnormal migration of worms is not seen.
Dose: 11mg/kg (not >g)
•DEC. Highly selective effect on microfilariae. Alters DEC. Highly selective effect on microfilariae. Alters
Mf membrane Mf membrane ÞÞreadily phagocytosed Uses: readily phagocytosed Uses:
Filariasis:2mg/kg TDS, Mf clears from blood in 7d, Filariasis:2mg/kg TDS, Mf clears from blood in 7d,
radical cure by 12 d-3 w. Tropical eosinophilia: 2-radical cure by 12 d-3 w. Tropical eosinophilia: 2-
4mg/kg TDS for 2-3 w. SE: ANV, dizziness, F, rash, 4mg/kg TDS for 2-3 w. SE: ANV, dizziness, F, rash,
pruritis, LAP & fall in BP may occur due to mass pruritis, LAP & fall in BP may occur due to mass
destruction of Mf & adult wormsdestruction of Mf & adult worms
high, comparable to mebendazole. Causes spastic high, comparable to mebendazole. Causes spastic
paralysis. Remarkably free of SE, tasteless, non paralysis. Remarkably free of SE, tasteless, non
irritant, abnormal migration of worms is not seen.irritant, abnormal migration of worms is not seen.
Dose: 11mg/kg (not >g)
•DEC. Highly selective effect on microfilariae. Alters DEC. Highly selective effect on microfilariae. Alters
Mf membrane Mf membrane ÞÞreadily phagocytosed Uses: readily phagocytosed Uses:
Filariasis:2mg/kg TDS, Mf clears from blood in 7d, Filariasis:2mg/kg TDS, Mf clears from blood in 7d,
radical cure by 12 d-3 w. Tropical eosinophilia: 2-radical cure by 12 d-3 w. Tropical eosinophilia: 2-
4mg/kg TDS for 2-3 w. SE: ANV, dizziness, F, rash, 4mg/kg TDS for 2-3 w. SE: ANV, dizziness, F, rash,
pruritis, LAP & fall in BP may occur due to mass pruritis, LAP & fall in BP may occur due to mass
destruction of Mf & adult wormsdestruction of Mf & adult worms
•PiperazinePiperazine Not used now a days. CI: neurological disorder Not used now a days. CI: neurological disorder
•NicolsamideNicolsamide DoC for tapeworms (DoC for tapeworms (T saginata, H nana, F T saginata, H nana, F
buski, H heterophyesbuski, H heterophyes))
•It kills the head of the tapeworm (inhibit oxidative It kills the head of the tapeworm (inhibit oxidative
phosphorylation). Dose: 1-3 tab (500mg)phosphorylation). Dose: 1-3 tab (500mg)
•IvermectinIvermectin DoC DoC in SS, in SS, O volvulus. Also for O volvulus. Also for scabies, scabies,
Filariasis&cutaneous larvae migrans. paralyze Filariasis&cutaneous larvae migrans. paralyze
nematodes&arthropods. Dose: single, 150-200mcg/kgnematodes&arthropods. Dose: single, 150-200mcg/kg
•PraziquantelPraziquantel effective in Schistosomiasis&Most flukes. Also effective in Schistosomiasis&Most flukes. Also
used against Taeniasis, used against Taeniasis,
Diphyllobothriasis,&neurocysticercosisDiphyllobothriasis,&neurocysticercosis
•Levamisole: not used as anthelminticLevamisole: not used as anthelmintic
•NicolsamideNicolsamide DoC for tapeworms (DoC for tapeworms (T saginata, H nana, F T saginata, H nana, F
buski, H heterophyesbuski, H heterophyes))
•It kills the head of the tapeworm (inhibit oxidative It kills the head of the tapeworm (inhibit oxidative
phosphorylation). Dose: 1-3 tab (500mg)phosphorylation). Dose: 1-3 tab (500mg)
•IvermectinIvermectin DoC DoC in SS, in SS, O volvulus. Also for O volvulus. Also for scabies, scabies,
Filariasis&cutaneous larvae migrans. paralyze Filariasis&cutaneous larvae migrans. paralyze
nematodes&arthropods. Dose: single, 150-200mcg/kgnematodes&arthropods. Dose: single, 150-200mcg/kg
•PraziquantelPraziquantel effective in Schistosomiasis&Most flukes. Also effective in Schistosomiasis&Most flukes. Also
used against Taeniasis, used against Taeniasis,
Diphyllobothriasis,&neurocysticercosisDiphyllobothriasis,&neurocysticercosis
•Levamisole: not used as anthelminticLevamisole: not used as anthelmintic
MCQMCQ
•Only ascaris as worm can cause intes. obstructionOnly ascaris as worm can cause intes. obstruction
•S stercoralis S stercoralis can cause hyperinfectioncan cause hyperinfection
•Ivermectin is an anthelmintic&anti-scabiesIvermectin is an anthelmintic&anti-scabies
•T trichiuria T trichiuria can cause Loeffler Syn.can cause Loeffler Syn.
•HW infestation is an imp. cause of IDAHW infestation is an imp. cause of IDA
•HW ,, occurs by swallowing eggsHW ,, occurs by swallowing eggs
•TT can cause rectal prolapseTT can cause rectal prolapse
•Only ascaris as worm can cause intes. obstructionOnly ascaris as worm can cause intes. obstruction
•S stercoralis S stercoralis can cause hyperinfectioncan cause hyperinfection
•Ivermectin is an anthelmintic&anti-scabiesIvermectin is an anthelmintic&anti-scabies
•T trichiuria T trichiuria can cause Loeffler Syn.can cause Loeffler Syn.
•HW infestation is an imp. cause of IDAHW infestation is an imp. cause of IDA
•HW ,, occurs by swallowing eggsHW ,, occurs by swallowing eggs
•TT can cause rectal prolapseTT can cause rectal prolapse
N
e
x
t
L
e
c
t
u
r
e
N
e
x
t
L
e
c
t
u
r
e
S
n
a
k
e
B
i
t
e
S
n
a
k
e
B
i
t
e
e
x
t
L
e
c
t
u
r
e
N
e
x
t
L
e
c
t
u
r
e
S
n
a
k
e
B
i
t
e
S
n
a
k
e
B
i
t
e
Tags
Categories
GeneralDownload
Download Slideshow Get the original presentation fileQuick Actions
Statistics
- Views 4,137
- Slides 102
- Favorites 3
- Age 3103 days
Related Slideshows
22
Pray For The Peace Of Jerusalem and You Will Prosper
RodolfoMoralesMarcuc
30 views
26
Don_t_Waste_Your_Life_God.....powerpoint
chalobrido8
32 views
31
VILLASUR_FACTORS_TO_CONSIDER_IN_PLATING_SALAD_10-13.pdf
JaiJai148317
30 views
14
Fertility awareness methods for women in the society
Isaiah47
29 views
35
Chapter 5 Arithmetic Functions Computer Organisation and Architecture
RitikSharma297999
26 views
5
syakira bhasa inggris (1) (1).pptx.......
ourcommunity56
28 views