Reading on Ascariasis lbercoides is too important

Reading on ascariasis is too important to mange those who are at risk

1. 2024/6/12 1

2. Pediatric ascariasis /Hook worm ESRAEL DIGA 2024/6/12 2

3. Presentation outline Introduction Pathophysiology Epidemiology Clinical presentation DDX Work up Rx and management Medication prevention 2024/6/12 3

4. Introduction A. lumbricoides which causes ascariaisis is the largest worms (nematodes) Female measures 50 by 0.5 cm It present in the GI tract The parasite is acquired through ingestion of embryonated egg It is usually asymptomatic 2024/6/12 4

5. continued AL has been present in humans for many thousand years Science only began to elucidate its biology in 17 th century Effective chemotherapy was only developed in the 20 th C 1758 Linnaeus proposed the name AL In 1862, Ransome reported that finding eggs in fecal samples was a reliable means of dx 2024/6/12 5

6. continued In 1862, Davaine concluded that ingestion of embryonated eggs produced ascariasis 2024/6/12 6

7. continued The genus Ascaris is composed of 17 species AL has high host specificity for humans and rarely for pigs A. suum has high host specificity for pigs 2024/6/12 7

8. Life cycle Life cycle data come from investigation of A suum in pigs and AL in mice Little is known about the interaction of AL larvae and humans Human ingest al eggs which contains stage 2 larvae The egg hatch in the jejenum release the stage 2 larvae 2024/6/12 8

9. continued They then penetrate the small intestine wall , inter portal venous circulation Migrates to the liver The larvae then migrates via the venous circulation to the pulmonary circulation and to the lungs They then break into alveolar spaces and molt into stage three and four larvae Then ascend the trachea, are swallowed, return to small intestine, molt for the final time and develop into mature adult , all over 14-20 days Total elapsed time from ingestion of eggs to mature adult 18-42 days 2024/6/12 9

10. continued The size range of the mature female is 20-40cm times 0.5- 0.6 cm The mature male 12-24 by 0.3-0.4 cm - Female produces approximately 200,000 eggs per day In the presence of male eggs are fertilized by copulation Female only infection produces non-fertilized non-infective eggs male only infections produces no eggs The pre patent period from ingestion of egg to detection of eggs in feces is 76-76 days 2024/6/12 10

11. continued The Life span of AL is 1-2 days Eggs fertilized and unfertilized released into environment Unfertilized eggs do not become infective Fertilized eggs can not infect untile they embryonate outside human body 2024/6/12 11

12. Continued To become infective, eggs must complete embryonization while in the soil The zygote develops into a stage 1 larva and molts to a stage 2 larva within the egg shell This occurs over 10-14 days at 28-32°C (82.4-89.6°F) and over 45-55 days at 16-18°C (60.8-64.4°) Several factors favor survival of the egg 2024/6/12 12

13. This includes Amount of moisture in the soil ( ie , clay soil vs sandy soil)

Protection from direct sunlight (quickly kills eggs)

Temperatures of 5-34°C (41-93.2°F): A temperatures of 40°C (104°F) is lethal. A temperature of 38°C (68.4°F) is lethal after 8 days.

Soil humidity of more than 4%: The length of survival is 4.5 hours or less with soil humidity of less than 4%, varies at 4-50% soil humidity, and is best at more than 50% soil humidity 2024/6/12 13

14. Continued Freezing at –15°C to –12°C (0.4-5°F) for 90 days kills all eggs except those at the single blastomere stage Depth in the soil is another major influence Experimentally, under similar climatic conditions, eggs survive 21–29 days on the surface 1.5 years or less at a depth of 10-20 cm, and 2.5 years or less at a depth of 40-60 cm 2024/6/12 14

15. Continued Under experimental conditions, eggs have sHowever, in general, eggs are expected to survive 28-84 daysurvived for 6-14 years in the soil However, in general, eggs are expected to survive 28-84 days In areas of endemicity, particularly where night soil (human feces) or untreated wastewater is used as fertilizer, the egg concentration is 100 eggs per gram of soil 2024/6/12 15

16. Pathophysiological mechanism Adult worms move throughout the GI tract and move in and out of orifices ( eg , biliary tract, pancreas, appendix, diverticula , Meckel diverticulum become incarcerated, leading to obstructive pathology The worms may die, leading to inflammation, necrosis, infection, and abscess formation 2024/6/12 16

17. continued Larvae during migration may be deposited in the brain, spinal cord, kidney, or other organs, leading to granuloma formation, They may become entwined in a bolus and obstruct the small bowel; this is most common in the terminal ileum This condition may be precipitated by the administration of an antihelminthic drug Only a small percentage of Ascaris infections produce serious, acute pathology 2024/6/12 17

18. Epidemiology In the United States, more than 4 million individuals are believed to be infected with Ascaris species Most infected persons are immigrants from developing countries 2024/6/12 18

19. International statistics Worldwide, more than 1.4 billion people are infected with ascariasis The distribution of cases is as follows: South America, Central America, and the Caribbean - 8.3% Africa and the Middle East - 16.7% Asia and the Oceania region - 75% 2024/6/12 19

20. Complications Intestinal obstruction - 63% Bile duct obstruction - 23% Perforation, peritonitis, or both - 3.2% Volvulus  - 2.7% Hepatitic abscess - 2.1% Appendicitis - 2.1% Pancreatitis - 1% Intussusception  - 0.5% Cebral encephalitis - 1% 2024/6/12 20

21. Continued Sepsis, sepsis syndrome, septic shock Ascaris pneumonia Löeffler syndrome Asthma exacerbation Other ectopic migration 2024/6/12 21

22. History Most individuals are asymptomatic, even in communities where the prevalence is high The most common manifestation is asymptomatic passage of an adult worm via the rectum Less frequently, a worm migrates to the oropharynx and is coughed out Ascaris eggs are often found in the stools of asymptomatic individuals in endemic areas 2024/6/12 22

23. Continued Some individuals with known significant worm burdens report anorexia, abdominal discomfort, and diarrhea however, these symptoms cannot be directly attributed to ascariasis 2024/6/12 23

24. Pulmonary ascariasis Symptoms develop 1-2 weeks after infection they vary from none to life-threatening (rare), depending on sensitization or considerable migrating worm burden Symptoms include chest pain (burning, aggravated by cough), cough (dry), dyspnea , fever, sputum (may be blood-tinged), and wheezing 2024/6/12 24

25. Continued A massive infestation can lead to Löeffler syndrome transient eosinophilia, transient lung infiltrates ascariasis remains the most common cause of this syndrome worldwide In areas of continuous transmission, pulmonary symptoms tend to be less evident 2024/6/12 25

26. Intestinal obstruction Partial or complete obstruction secondary to an entangled worm bolus can occur at any age however, 85% of cases occur in children aged 1-5 years and most occur at terminal ileum The worm bolus may also cause intussusception or volvulus Severe, sharp, colicky abdominal pain with associated vomiting predominates The vomit may contain worms Complete obstruction may begin subsequent to the administration of an antihelminthic 2024/6/12 26

27. Continued particularly in the setting of acute abdominal pain or partial bowel obstruction Specific concern surrounds the administration of pyrantel pamoate, which causes a spastic paralysis of the worms Complete obstruction has also been reported with piperazine (flaccid paralysis of worms) and mebendazole (single large dose) 2024/6/12 27

28. Hepatobiliary and pancreatic ascariasis and other GI diseases Migrating adult worms (most common), worm fragments, or eggs can cause acalculous cholecystitis ascending cholangitis appendicitis biliary colic gastric hemorrhage granulomatous peritonitis liver abscess Meckel diverticulum inflammation obstructive jaundice Pancreatitis peritonitis peritoneal granulomatosis ( ie , ductal and/or intestinal perforation or migration through perforation 2024/6/12 28

29. Extra-GI conditions Worms may migrate to the upper respiratory tract ( ie , throat, nose, lacrimal ducts, and inner ear Experimental studies report that the migrating larvae can enter many tissues, including the brain, kidney, and lymph nodes, but cannot survive Several case reports have suggested encephalopathy secondary to Ascaris larvae 2024/6/12 29

30. Differential Diagnoses Appendicitis Imaging

Asthma

Hypersensitivity Pneumonitis Pediatric Cholecystitis Pediatric Gallstones ( Cholelithiasis )

Pediatric Malabsorption Syndromes

Pediatric Pancreatitis and Pancreatic Pseudocyst 2024/6/12 30

31. Laboratory Studies A microscopic examination finding of eggs in the feces confirms the diagnosis This is performed using a direct method (stool mixed with saline) or after concentrating the stool Fertilized eggs are easier to identify than unfertilized eggs and decorticate eggs Male-only ascaris infections produce no eggs Microscopic examination of gastric contents may reveal larvae and eggs 2024/6/12 31

32. Chest radiography According to Löeffler , "The x-ray shadows are variable, unilateral or bilateral, fleecy or dense and small and round big and irregular; they may be very extensive CT MRI 2024/6/12 32

33. Treatment and mgt Pulmonary cases Most cases are asymptomatic Most symptomatic cases are mild and self-limited (days) and do not require therapy Bronchospasm can be managed with conventional therapy Severe cases can be managed with systemic steroids and oxygen supplementation 2024/6/12 33

34. Partial small bowel obstruction In the absence of signs of toxicity , fever, tachycardia , protracted vomiting, peritoneal signs persisting abdominal pain, or a palpable mass in the same site for more than 24 hours, several conservative management strategies, including supportive care, have proven efficacious 2024/6/12 34

35. Hepatobiliary and pancreatic ascariasis This typically manifests as biliary colic, acalculous cholecystitis, ascending cholangitis, pancreatitis, or hepatic abscess. Ascariasis is a common cause of these conditions in endemic countries 2024/6/12 35

36. Surgical care Intestinal obstruction Appendicitis Volvulus Intussusception Ischemic bowel 2024/6/12 36

37. Medications Several drugs are efficacious for the treatment of ascariasis , including the asymptomatic intestinal phase; this involves the periodic deworming of children (symptomatic and asymptomatic), a reduction of the public health burden The efficacy for albendazole , mebendazole , and pyrantel is 88%, 95%, and 88%, respectively. For hookworm, a common infecting STH, the efficacies for the same medications are 72%, 15%, and 31%, respectively; therefore, using albendazole is more efficacious, when a coinfection of ascaris and hookworm is suspected 2024/6/12 37

38. Continued In general, antihelminthic drugs are not recommended in patients from endemic areas who have acute abdominal pain, with or without partial bowel obstruction, Albendazole has the advantages of pediatric dosing for individuals younger than 2 years, good tolerability, and efficacy in the treatment of ascariasis, hookworm infection, pinworm infection, strongyloidiasis, and trichuriasis.struction 2024/6/12 38

39. Mebendazole Causes worm death by selectively and irreversibly blocking uptake of glucose other nutrients in susceptible adult intestine where helminths dwell Causes slow immobilization and death of organisms Administration over 3 d reduces risk of worm bolus formation Available as a 100-mg chewable tablet that can be swallowed whole, chewed, or crushed and mixed with food 2024/6/12 39

40. Albendazole Broad-spectrum anthelmintic agent effective against Ascaris species, hookworm, tapeworm, liver fluke, and pinworms. Decreases ATP production in worm, causing energy depletion, immobilization, and finally death. 2024/6/12 40

41. piperazine Causes flaccid paralysis of the helminth by blocking response of Ascaris species worm to acetylcholine; thus, expels the worm by normal intestinal peristalsis 2024/6/12 41

42. Ivermectine Binds selectively with glutamate-gated chloride ion channels in invertebrate nerve and muscle cells, causing cell death. Half-life is 16 h; metabolized in liver 2024/6/12 42

43. Prevention Prevention consists of improved sanitation and education about the disease In endemic areas, school screening has demonstrated effectiveness in detection and early treatment of asymptomatic carriers Benefits in health and educational performance have been reported with large-scale treatment of school-aged children every 6 months in countries where ascariasis is a public health problem 2024/6/12 43

44. continued Three strategies have been identified to control STH infections chemotherapy, health education, and sanitation 2024/6/12 44

45. Sanitation Sanitation in developed countries is currently too expensive to be provided to the more than 2 billion people who lack safe disposal of their feces 2024/6/12 45

46. Hook worm Hookworm infections are common in the tropics and subtropics The prevalence of hookworm infection is highest in sub-Saharan Africa, followed by Asia, Latin America, and the Caribbean Infection is rare in regions with less than 40 inches of rainfall annually There are two species of hookworm that cause human infection Ancylostoma duodenale (in Mediterranean countries, Iran, India, Pakistan Necator americanus (in North and South America, Central Africa, Indonesia, islands of the South Pacific, and parts of India) 2024/6/12 46

47. Three favorable conditions for traansimission Three conditions are important for transmission of hookworm infection : human fecal contamination of soil favorable soil conditions for larval survival (moisture, warmth, shade ) contact of human skin with contaminated soil Individuals who walk barefoot or with open footwear in fecally contaminated soil are at risk for infection 2024/6/12 47

48. LIFE CYCLE begins with passage of eggs from an adult host into the stool Hookworm eggs hatch in the soil to release rhabditiform larvae that mature into infective filariform larvae Infection is transmitted by larval penetration into human skin as few as three larvae are sufficient to produce infection 2024/6/12 48

49. conntinued From the skin, larvae migrate into the blood vessels and are carried to the lungs Approximately 8 to 21 days following infection, larvae penetrate into the pulmonary alveoli ascend the bronchial tree to the pharynx, and are swallowed In addition to percutaneous larval penetration (the principal mode of transmission), A. duodenale infection may also be transmitted by the oral route 2024/6/12 49

50. continued In the small intestine, the larvae mature into adult worms attach to the intestinal wall with resultant blood loss A. duodenale larvae may persist within tissues before returning to the intestine with delay in egg laying Following fertilization by adult male worms, gravid female adults lay eggs within the bowel Eggs become detectable in feces about six to eight weeks following infection with N. americanus Most adult worms are eliminated in one to two years though infection can persist for many years 2024/6/12 50

51. Clinical manifestation The potential manifestations reflect the four phases of hookworm infection Dermal penetration by infecting larvae Transpulmonary passage Acute gastrointestinal symptoms Chronic nutritional impairment 2024/6/12 51

52. Cutaneous manifestations Dermal penetration of the skin frequently produces a focal pruritic maculopapular eruption at the site of larval penetration (termed "ground itch ") 2024/6/12 52

53. Transpulmonary passage Transpulmonary passage is usually asymptomatic A mild cough and pharyngeal irritation may occur during larval migration in the airways, though eosinophilic pulmonary infiltrates Pulmonary symptoms attributable to hookworm have not been observed experimentally infected volunteers 2024/6/12 53

54. Acute gastrointestinal symptoms Patients may experience gastrointestinal symptoms at the time of larval migration to the small intestine Nausea, diarrhea, vomiting, midepigastric pain (usually with postprandial accentuation ) increased flatulence 2024/6/12 54

55. Chronic nutritional impairment The major impact of hookworm infection is on nutritional status his is particularly important in endemic areas where children and pregnant women may have limited access to adequate nourishment In addition, maternal hookworm infection is associated with low birth weight 2024/6/12 55

56. continued Hookworms cause blood loss during attachment to the intestinal mucosa by lacerating capillaries ingesting extravasated blood this process is facilitated by the production of anticoagulant peptides that inhibit activated factor X and factor VIIa /tissue factor complex inhibit platelet activation lead to anemia and contribute to impaired nutrition, especially in patients with heavy infection 2024/6/12 56

57. DIAGNOSIS Clues to the presence of hookworm infection include clinical manifestations as described above The diagnosis is established by stool examination; there are no reliable serologic tests available 2024/6/12 57

58. Stool examination Stool examination for the eggs of N. americanus or A. duodenale is useful for detection of clinically significant hookworm infection Fecal egg excretion becomes detectable about eight weeks after dermal penetration of N. americanus infection up to 38 weeks after dermal penetration of A. duodenale Stool examination for detection of hookworm infection is insensitive Serial examinations may be required to make the diagnosis. 2024/6/12 58

59. continued The eggs of N. americanus and A. duodenale are morphologically indistinguishable Speciation is not necessary for clinical purposes and is only possible if adult worms are detected in stool or at endoscopy 2024/6/12 59

60. Eosinophilia Otherwise unexplained eosinophilia may be a major clue to the presence of a parasitic infection Eosinophilia has been attributed to persistent attachment of adult worms to the intestinal mucosa The degree of eosinophilia with hookworm infection is usually mild and varies during the course of the disease 2024/6/12 60

61. treatment Iron replacement alone can lead to restoration of a normal hemoglobin level in individuals with hookworm infection but anemia recurs unless anthelminthic therapy is given 2024/6/12 61

62. Chemotherapy 2024/6/12 62

63. Health education In terms of education, better-educated households have better health The challenge is to educate communities without clashing with local customs and cultures 2024/6/12 63

64. Chemotheraphy The goal is to reduce the intensity of STH infections in the community Three chemotherapy strategies have been field tested for reducing the intensity of STH infections in the community: 1/universal/mass treatment (all ages, both sexes, no exceptions ) 2/targeted treatment (defined age, sex, or other identifier) 3/selected treatment (current diagnosis of STH infection ) 2024/6/12 64

65. Continued Only universal and targeted treatments are effective Selected treatment does have a role, although it does not reduce community STH infection intensity Treatment delivered to children through the schools at intervals of a year, 6 months, 4 months, or 3 months has been shown to be effective When given every 3 months to children in one study, a significant decrease in adult intensity was noted, as wellective 2024/6/12 65

66. challenges in our specific community Not familiar with ways of trnsmission Considering worms as parts of organ system The association between ascariasis and BUDA low socio economic status Poor hand washing practices/sanitation and hygiene Educational status Open defecation in rural areas/ no appropriate toilets Accesseblity for cean drinking water 2024/6/12 66

67. Way forward 2024/6/12 67