Gastrointestinal Infections in Children2_compressed.pdf

Gastrointestinal Infections in Children

1. Gastrointestinal Infections
in Children
G.R. Khasanova
MD, PhD, Professor

2. Content
Epidemiology
The main causative agents
Pathogenesis. Types of diarrhea
Clinical syndromes
Diagnosis of GI infections
Etiotropic treatment
Dehydration. Treatment.
Preventive measures

3. Global view
Diarrheal diseases are second cause of death worldwide
Leading cause of childhood death
About 4,5-6 millions of children die each year
(>12.000/day)
Depends on country: In India attack rate is 7-19 per
person per year in children < 2 years; in the US: 1,5-5)
Diarrheal diseases are closely related to malnutrition
Malnutrition promotes diarrhea
Diarrhea exacerbates nutritional deficiencies

4. Epidemiology (1)
Determinants of risk: who, where, when
Who:
Age
Living conditions
Food/water
Where: pattern of etiologic agents, specific for every
area
When: seasonal changes in predominant agents

5. Epidemiology (2)
Concerned pathogen transmitted mostly through
fecal-oral route:
Alimentary
Water
Contact
Some viral infections also may be airborne
By the primary source:
From human (acute disease or chronic carrier)
Most of the cases in developing world (cholera, typhoid)
From animals (poultry, bovine, porcine, etc)
Most of the cases in developed countries (salmonellosis, etc)

6. Etiology
Bacteria:
Salmonella enteritidis, Shigella spp., Escherichia Coli,
Yersinia enterocolitica, Vibrio Cholerae
Viruses:
Rotavirus, Norwalk-viruses, Enteroviruses
Fungi:
Candida
Protozoa:
Entamoeba histolitica, Giardia lamblia,Cryptosporidia,
Cyclosporidia

7. Pathogenesis (1)
Host factors:
Genetics (type O blood group more susceptible to
cholera, type A -giardiasis, etc)
Age (changes in gut mucus, receptors, immunity,
nonspecific protective factors, human milk, gastric
acidity)
Intestinal motility
Intestinal immunity (phagocytosis, humoraland cell-
mediated)
Enteric microflora(Bifidobacteriae, Bacteroides, etc)
Personal hygiene

8. Pathogenesis (2)
Microbial factors:
Toxines (exo-or endotoxines):
Enterotoxines (cholera toxine, enterotoxigenic E. Coli,
Salmonella, Klebsiella)
Cytotoxines (Shiga-toxine, C.perfingens, C.difficile, EHEC
O26, 39, 128, 157)
Neurotoxine (Cl.botulinum, St.aureus, Bacillus cereus)
Attachment
Proinflamatory mediators
Invasiveness
Other factors (motility, chemotaxis, mucinase
production, etc)
Viral factors (selective cell destruction)

9. Pathogenesis (3)
Infective dose of the agent
The higher virulence the lower infective dose
Low-dose may be transmitted through contact
High-dose –mostly alimentary (or through water)
Pre-existing toxin in food
Food poisoning
Different ratio between toxin/microbe in food
Mostly Staphylococcus aureus

10. Types of diarrhea
Invasive
Shigellosis, enteroinvasive E.Coli, Clostridium deficile
Secretory
Cholera, enterotoxygenic E.Coli, Klebsiella, Salmonella,
Campylobacter
Osmolary
Viral diarrheas
Criptosporidiosis

11. Main clinical syndromes
Incubation 0-7 days
Intoxication
Fever, chills, dizziness, fatigue, etc
Gastrointestinal syndromes:
Gastritis
Enteritis
Colitis
Dehydration
Specific syndromes/symptoms

12. Gastritis
Do not mix with banal (catarrhal) gastritis
Irritation/infalammation of the stomach mucus
Key feature: vomiting
Other signs: nausea, pain in epigastria, loss of appetite
Can lead to dehydration in case of repeated severe
vomiting
Example: food poisoning, salmonellosis

13. Enteritis
Inflammation/damage of the small intestine mucosa
or hypersecretion due to toxin effect
Key feature: watery diarrhea, stool of large amount,
may be foamy
Other signs: pain in mesogastrium, bloating
Often results in dehydration
Example: rotavirial diarrhea, salmonellosis

14. Colitis
Inflamation/damage (ulcers) of the large-bowel
mucosa due to bacterial invasion
Key feature: pathologic inclusions in stool (mucus,
blood, pus)
Other features: spastic pain in iliac region (mostly in
the left), tenesmus, or their equivalents in children,
incompletely closed anus
Dehydration is rare if no other syndromes
Example: shigellosis

15. Dehydration
One of the main steps in the pathogenesis of all GI
infections
Clinically significant dehydration –40-42% of all cases
of GI infection
Main cause of death, especially in children
Can progress very rapidly
Requires immediate attention

16. Types of dehydration
Hyperosmolar
Body loses more water than salts
Pronounced clinical picture
Isoosmolar
Proportional lost of salts and water
Hypoosmolar
Body loses more salts than water
Symptoms of cardiovascular insufficiency

17. Grades of dehydration
3 grades of dehydration in children, depending on
amount of liquids lost and clinical presentation
Stage of dehydration defines therapy

18. Dehydration of I degree
Weight deficiency up to 5 %
The most precise sign
Key clinical feature: dryness of visible mucosa
Other signs: thirst
No signs of cardiovascular system involvement
Causal factors:
Vomiting –not frequent (1-3 times)
Diarrhea not more than 5 times a day, or with small
amount

19. Dehydration of II degree
Weight deficiency 5-9%
Key clinical feature: dryness of skin, decreased diuresis
Other signs: sunken fontanel, softness of the eyeball,
signs of cardiovascular involvement (tachycardia,
increased or decreased blood pressure, decreased CVP,
limb coldness), may be tachypnea
Causal factors:
Vomiting –repeated(>3 times)
Diarrhea up to 10 times a day, watery, profound

20. Dehydration of III degree
Weight deficiency 10% or more
Key clinical feature: low tissue tension, dramatically
decreased diuresis (<10 ml/h)
Other signs: deeply sunken fontanel, sunken, dry
eyeball, dry skin, signs of cardiovascular involvement
(severe tachycardia, decreased blood pressure,
negative CVP, limb coldness), dyspnea, no tears when
crying, lethargy
Causal factors:
Vomiting –severe, repeated, with large volume
Diarrhea more than 10 times a day, watery, profound

21. Diagnosis (1)
Careful history
Family or other contact with person with diarrhea
Food history
Travelling
Underlying diseases
History of recent antibiotic use
Physical examination –see “syndromes”
Lab data:
Bacteriological method –very specific, but sensitivity as
low as 30%

22. Diagnosis (2)
Stool sample
Leukocytes, erythrocytes invasive disease (colitis)
Maldigested fat, vegetable or meat fibers –pancreatic
insufficiency
Lipid droplets –malabsorbtion with steatorrhea
Stool pH :
normal rate –4,7-5,1 –breastfed infants, m/b~7 in other age
groups.
pH<5,0 –lactose intolerance.

23. Diagnosis (3)
Lab data
CBC may be suggestive of viral or bacterial infection
Serological methods
Applicable to some diseases
May be non-specific
Pair-serum test maybe needed (takes up to 14 days)

24. Diagnosis (4)
In most cases (more than 70%) etiology of GI infection
remains unclear
Treatment of GI infection is based on the syndroms
Etiotropic treatment needed rarely

25. Rehydration
Compensation of fluid deficiency
Oral rehydration (preferable!)
More physiological
Much less complications
Easier to perform
Parenteral rehydration
Allows to correct severe deficits
Implemented when oral rehydration is not feasible or
not enough

26. Liquids volume
Consists of current liquid deficiency + physiological
needs + continuing liquids loss
Liquid deficiency can be estimated on the basis of body
mass deficiency or clinical picture (degree of
dehydration)
Physiological needs
Should be checked in guidelines (Infants: 120-140 ml/kg, 1-2
years: 100-120 ml/kg, 2-5 years: 80-100 ml/kg, 5-10 years: 60-80
ml/kg, 10-14 years: 50-60 ml/kg, 14-18: 40-50 ml/kg)
Continuing loss: should be measured
Estimates: vomiting: 20-40 ml/kg, diarrhea:30 –100 ml/kg,
fever: 10 ml/kg

27. Solutions for oral rehydration
Should compensate deficiency of water AND salts
Glucose-and-salt solutions. Glucose promotes
absorption of the salts and water
3,5 g NaCl, 2,5 g NaHCO3, 1,5 g KCl, 20 g glucose per liter
Large tablespoon of glucose, ¾ teaspoon of salt, ½
teaspoon of sodium bicarbonate, 200 ml of orange juice
and fill-up with water to 1 liter
Rice water, decoction of maize, millet flour
Pharmacy-made preparations or solutions: Regidron,
Oralid, etc.

28. Rules of oral rehydration
In dehydration of I degree only OR
OR should be given intermittently in small portions
5-20 ml every 1-10 min
OR should be given insistently –it is the main
treatment for a child with GI infection
Enough volume
Water or other soft, non-irritating drinks (tea, still
mineral water) may be added

29. Parenteral rehydration
Implemented in addition to oral rehydration, when:
OR is unfeasible (severe vomiting)
OR can not substitute the water deficiency fast enough
(severe continuing liquid loss, ex: cholera)
Severe dehydration with shock (cardiovascular
insufficiency due to severe hypovolemia)
Consist mainly of glucose and salts solutions, colloid
solutions may be added
Glucose:salts = depends on type of dehydration and age
of the patient

30. OR:PR ratios
Dehydration I: OR 100%
Dehydration II: PR 30-50%
Dehydration III: PR 50-75% (up to 100% if needed)
Decrease amount of PR as soon as possible,
proportionally with increasing OR volume
Mind serious complications of PR –hypervolemia,
cardiovascular complications (up to cardiac standstill)

31. Antibiotics (1)
In most cases are not needed!
Mild or moderate bacterial disease
Viral diarrhea
May prolong carrier state (Salmonella)
Resistance to antibiotics is increasing, esp. Shigella
and Salmonella
Antibiotic resistance test needed for effective therapy
Indicated in case of dysentery, caused by Shigellaor
Entamoeba hystolitica, in cholera and typhoid fever
Needed in immunocompromised host

32. Antibiotics (2)
Mind contraindications in children:
Fluoroquinolones up to 14
Tetracyclines
Chloramphenicol (levomycetine), especially in infants
Should be prescribed specifically to the causing
microorganism
Campilobacter–azythromycin, E.Coli–clotrimazol,protected
penicillins, Yersinia enterocolitica –gentamycin

33. Other treatment
Spasmolytics
Antipyretics and/or anti-inflammatory drugs
Sorbents
Enzymes
Bacterial preparations
Antimotility drugs –EXTREMLY narrow indications!
Antiemetic –in case of severe vomiting

34. Strict bed rest –only in few infections.
Typhoid fever–for prevention of life-threatening
complications.
In another cases –bed rest only for acute phase
in severe cases of disease.

35. Diet
Is important part of treatment of patients with GI-
infections (exclusion of fresh fruits, vegetables, fruit
juice, spicy food).
Special diet is recommended for infants with:
Lactose intoleranse;
Cow milk intolerance;
Ketosis.

36. Lactase insufficiency
Insufficientproductionoflactasebyintestinalcells.
Lactase–isanenzyme,convertinglactoseintoglucoseandgalactose
Lactoseintoleransem/bsecondarybecauseofinjuryofglandularenteric
cells(rotaviralinfection!)
Collectionofmuchamountsoflactoseinsidetheintestinalspace
Highosmolarityofsubstrateleadstogasformation(methan,hydrogen),
abdominalpainanddiarrhea(watery,withacidsmell–osmoticdiarrhea).
Vomittingisnotcommon.
Lactose-freediet(mictures,basedonsoyorhypolactose-mictures,
fermentedmilkproducts).
Brestfeedinginfants–givewater(1/4-1/3ofvolumeofmilk)todecrease
concentrationoflactose.

37. Cow milk intolerance
Cowmilkincreasesintestinalpermeabilityeveninhealthy
children.Cowmilk-fedinfantlosesupto7mlofbloodeveryday.
Incowmilkintolerance:moreseverebloodloss,decreased
absorptionofproteins,fat,carbohydratesandweightloss.
Clinical pattern: ~ invasive diarrhea (stool, containing blood and
mucus).
May worsen the course of GI-infections (especially with invasive
diarrhea)
Milk, meat, some medications (enzymes)–provoke symptoms.
Avoidance of cow milk.

38. Ketosis
Repeated vomiting with acetone smell.
Dehydration
High temperature
Abdominal pain
Abnormal blood analysis
Ketonuria and ketonemia, hypoglycemia, metabolic asidosis
Biochemical basis –oxalic acid deficiency, followed by decreased
activity of acetilcoenzyme A.
May be provoked by any stress (common in GI-infections).
Rehydration (per os + i/v): glucose, salt, NaHCO3.

39. Prevention and control
Public health measures:
Improved water supply and sanitation facilities
Food quality control
Personal measures
Personal hygiene
Food hygiene
For infants –breastfeeding
Vaccination –limited (typhoid fever, rotavirus)