Giardiasis

definition ,causative factor ,epidemiology ,signs and symptoms ,diagnosis ,differential diagnosis ,complications,treatment ,prognosis .prevention

1. Giardiasis Prof. Dr. Saad S Al Ani Senior Pediatric Consultant Head of Pediatric Department Khorfakkan Hospital Sharjah, UAE [email protected]

2. Giardia intestinalis https://www.cdc.gov/parasites/giardia / 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 2

3. Facts Giardia  is a microscopic parasite that causes the diarrheal illness known as giardiasis .  Giardia is found on surfaces or in soil, food, or water that has been contaminated with feces from infected humans or animals . https://www.cdc.gov/parasites/giardia / 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 3

4. Facts (Cont.) Giardia can be spread in different ways, water (drinking water and recreational water) is the most common mode of transmission . Giardia   is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it tolerant to chlorine disinfection https://www.cdc.gov/parasites/giardia / 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 4

5. Facts (Cont.) Giardia usually spreads when  Giardia lamblia  cysts within feces  contaminate food or water which is then eaten or drunk Giardia is one of the most common parasitic human diseases globally 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 5 Minetti, C; Chalmers, RM; Beeching, NJ; Probert, C; Lamden, K (27 October 2016). "Giardiasis".  BMJ (Clinical research ed.) .  355 : i5369.  Esch KJ, Petersen CA (January 2013). "Transmission and epidemiology of zoonotic protozoal diseases of companion animals "   Clin Microbiol Rev .  26  (1): 58–85. 

6. Facts (Cont.) Infection is more common in children than in adults Infection with  Giardia intestinalis  most often results from: F ecal-oral transmission Ingestion of contaminated water 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 6 Huston CD. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. Feldman M, Friedman LS, Brandt LJ.  Intestinal Protozoa . 8th ed. Philadelphia, PA: Saunders, An imprint of Elsevier Inc ; 2006. 2: 2420-2423 / 106.

7. Contaminated food is a less common etiology G intestinalis  is a particularly significant pathogen for people with: Malnutrition Immunodeficiencies Cystic fibrosis . 10/06/2018 7 Giardiasis Prof. Dr. Saad S Al Ani Facts (Cont.)

8. Most infections are asymptomatic Giardia  is found in healthy people in endemic areas Asymptomatic carriage with excretion of high numbers of cysts in stools is common . 10/06/2018 8 Giardiasis Prof. Dr. Saad S Al Ani Facts (Cont.)

9. Giardiasis does not have any race predilection Giardiasis is slightly more c ommon in males than in females Giardiasis affects people of all ages Infection is rare during the first 6 months of life in breastfed infants infants and young children have an increased susceptibility to giardiasis 10/06/2018 9 Giardiasis Prof. Dr. Saad S Al Ani Facts (Cont.) 1.Laupland KB, Church DL. Population-based laboratory surveillance for Giardia sp. and Cryptosporidium sp. infections in a large Canadian health region.  BMC Infect Dis . 2005 Sep 16. 5:72 2.John CC. Giardiasis and Balantidiasis . Kliegman RM, Behrman BE, Jenson HB, Stanton BF.  Nelson Textbook of Pediatrics . 279. Philadelphia, PA: Saunders, An imprint of Elsevier Inc ; 2007. 18th ed : 1462-1464 .

10. Cysts may survive for nearly 10/06/2018 10 Giardiasis Prof. Dr. Saad S Al Ani Golden Age of Gaia Minetti, C; Chalmers, RM; Beeching, NJ; Probert, C; Lamden, K (27 October 2016). "Giardiasis".  BMJ (Clinical research ed.) .  355 : i5369.  in cold water

11. Risk factors Include: T ravel in the developing world C hanging diapers E ating food without cooking it O wning a dog 10/06/2018 11 Giardiasis Prof. Dr. Saad S Al Ani Minetti, C; Chalmers, RM; Beeching, NJ; Probert, C; Lamden, K (27 October 2016). "Giardiasis".  BMJ (Clinical research ed.) .  355 : i5369

12. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 12 of raw water supplies from lakes, streams, and ponds Giardia has been found in as many as Robertson LJ, Forberg T, Gjerde BK. Giardia cysts in sewage influent in Bergen, Norway 15-23 months after an extensive waterborne outbreak of giardiasis.  J Appl Microbiol . 2008 Apr. 104(4):1147-52 Dreamstime.com

13. Giardia has been found in as many as 10/06/2018 13 Giardiasis Prof. Dr. Saad S Al Ani Dreamstime.com of filtered water samples Robertson LJ, Forberg T, Gjerde BK. Giardia cysts in sewage influent in Bergen, Norway 15-23 months after an extensive waterborne outbreak of giardiasis.  J Appl Microbiol . 2008 Apr. 104(4):1147-52

14.   In 2013, there were about 10/06/2018 14 Giardiasis Prof. Dr. Saad S Al Ani people worldwide with symptomatic giardiasis Esch KJ, Petersen CA (January 2013). "Transmission and epidemiology of zoonotic protozoal diseases of companion animals "   Clin Microbiol Rev .  26  (1): 58–85. 

15. Global rates of giardiasis 10/06/2018 15 Giardiasis Prof. Dr. Saad S Al Ani Hotel Can Darder Caracas Chronicles in the developed world in the developing world Minetti, C; Chalmers, RM; Beeching, NJ; Probert, C; Lamden, K (27 October 2016). "Giardiasis".  BMJ (Clinical research ed.) .  355 : i5369 . 

16. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 16 of those infected have no symptoms . Minetti , C; Chalmers, RM; Beeching, NJ; Probert, C; Lamden, K (27 October 2016). "Giardiasis".  BMJ (Clinical research ed.) .  355 : i5369. 

17. Person-to-person spread is common , with 10/06/2018 17 Giardiasis Prof. Dr. Saad S Al Ani of family members with infected children themselves becoming infected www.mychaos.co.uk

18. The rate of symptomatic infection varies from 10/06/2018 18 Giardiasis Prof. Dr. Saad S Al Ani in the natural setting

19. The incubation period averages 10/06/2018 19 Giardiasis Prof. Dr. Saad S Al Ani weeks with a mean days

20. Duration of symptoms 10/06/2018 20 Giardiasis Prof. Dr. Saad S Al Ani The average duration of symptoms in all ages ranges from weeks

21. The infective dose The infective dose is low in humans 10/06/2018 21 Giardiasis Prof. Dr. Saad S Al Ani Cysts of are capable of causing clinical disease in Subjects

22. Remember Ingestion 10/06/2018 22 Giardiasis Prof. Dr. Saad S Al Ani Cysts results in a infection rate

23. Predisposing factors to symptomatic infection Include : Hypochlorhydria Various immune system deficiencies Blood group A Malnutrition 10/06/2018 23 Giardiasis Prof. Dr. Saad S Al Ani

24. Giardiasis ( beaver fever) Is a parasitic disease caused by  Giardia lamblia Giardiasis is a major diarrheal disease found throughout the world 10/06/2018 24 Giardiasis Prof. Dr. Saad S Al Ani Esch KJ, Petersen CA (January 2013). "Transmission and epidemiology of zoonotic protozoal diseases of companion animals".  Clin Microbiol Rev .  26  (1): 58–85 Daly ER, Roy SJ, Blaney DD, et al. Outbreak of giardiasis associated with a community drinking-water source.  Epidemiol Infect . 2010 Apr. 138(4):491-500

25. Giardiasis usually represents a zoonosis with cross-infectivity between animals and humans.  Giardia intestinalis  has been isolated from the stools of beavers, dogs, cats, and primates 10/06/2018 25 Giardiasis Prof. Dr. Saad S Al Ani Zonosis

26. Giardia  life cycle Giardia   has one of the simplest life cycles of all human parasites The life cycle is composed of 2 stages : (1) The trophozoite which exists freely in the human small intestine ( 2) The cyst, which is passed into the environment . No intermediate hosts are required . 10/06/2018 26 Giardiasis Prof. Dr. Saad S Al Ani

27. Giardia  life cycle (Cont.) 10/06/2018 27 Giardiasis Prof. Dr. Saad S Al Ani https:// commons.wikimedia.org/wiki/File:Giardia_life_cycle_nl.svg

28. Giardia cyst https://www.sciencesource.com/archive/Giardiasis-Cysts 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 28

29. The trophozoite form of  G lamblia The trophozoite form of  G lamblia   Teardrop-shaped Measures 9-21 micrometers long by 5-15 micrometers wide. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 29 https://www.flickr.com/photos

30. The trophozoite form of  G lamblia (Cont.) Has a convex dorsal surface and a flat ventral surface that contains the ventral disk, a rigid cytoskeleton composed of microtubules and microribbons. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 30 https://www.flickr.com/photos

31. The trophozoite form of  G lamblia (Cont.) Contains 4 pairs of flagella, directed posteriorly, that aid the parasite in moving. Two symmetric nuclei with prominent karyosomes produce the characteristic face like image that appears on stained preparations 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 31 https://www.flickr.com/photos

32. The cyst form of G lamblia The cyst form of G lamblia Smooth-walled and oval in shape Measuring 8-12 micrometers long by 7-10 micrometers wide . 10/06/2018 32 Giardiasis Prof. Dr. Saad S Al Ani http:// www.phsource.us

33. The cyst form of G lamblia (Cont.) As the cyst matures, nuclear division occurs and readies the cyst to release 2 trophozoites upon excystation Excystation occurs within 5 minutes of exposure of the cysts to an environment with a pH between 1.3 and 2.7 10/06/2018 33 Giardiasis Prof. Dr. Saad S Al Ani http:// www.phsource.us

34. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 34 http:// ninajuling.tripod.com/secondpage.htm

35. Epidemiology United States statistics Most water-borne outbreaks in the United States have occurred in western mountain regions (e.g., Rocky Mountains, Sierra Nevada, Cascades ) The incidence of giardiasis is high among individuals who camp and backpack in mountainous Western states Other groups at increased risk for infection include : Children Homosexual men Individuals with immunoglobulin deficiency states (inherited or acquired ). 10/06/2018 35 Giardiasis Prof. Dr. Saad S Al Ani

36. Endemic infection occurs most commonly from July through October among children younger than 5 years and adults aged 25-39 years . Carrier rates as high as 30-60% have been documented among: Children in day care centers Institutions On Native American reservations . 10/06/2018 36 Giardiasis Prof. Dr. Saad S Al Ani Epidemiology (Cont.)

37. Epidemiology (Cont.) International statistics Giardia  has a worldwide distribution, occurring in both temperate and tropical regions Prevalence rates vary from 4-42 % In the developing world,  G intestinalis  infects infants early in life and is a major cause of epidemic childhood diarrhea . Prevalence rates of 15-20% in children younger than 10 years are common 10/06/2018 37 Giardiasis Prof. Dr. Saad S Al Ani Caccio SM, Ryan U. Molecular epidemiology of giardiasis.  Mol Biochem Parasitol . 2008 Aug. 160(2):75-80

38. Giardia  has been identified as the causative agent in a large percentage of cases among travellers to the region of St. Petersburg, Russia, where tap water is the primary source The highest prevalence of  G intestinalis  reached 73.4% in Western Nepal The Dhaka study performed within the urban areas had identified  G intestinalis  in 11% of diarrheal stool specimens 10/06/2018 38 Giardiasis Prof. Dr. Saad S Al Ani Epidemiology (Cont.) Dib HH, Lu SQ, Wen SF. Prevalence of Giardia lamblia with or without diarrhea in South East, South East Asia and the Far East.  Parasitol Res . 2008 Jul. 103(2):239-51

39. Clinical presentation Clinical signs and symptoms of giardiasis include the following: 10/06/2018 39 Giardiasis Prof. Dr. Saad S Al Ani Clinical signs and symptoms Diarrhea Nausea Low-grade fever (infrequent) Malaise, weakness Malodorous, greasy stools Various neurologic symptoms (e.g., irritability, sleep disorder, mental depression, neurasthenia) Abdominal distention Anorexia Flatulence Weight loss Abdominal cramps Vomiting Urticaria

40. Remember Diarrhea is the most common symptom of acute  Giardia  infection, occurring in 10/06/2018 40 Giardiasis Prof. Dr. Saad S Al Ani of symptomatic subjects Abdominal cramping , bloating , and flatulence occur in of symptomatic patients

41. Gastrointestinal manifestations Abrupt onset (rare) a small number of persons develop abrupt onset of : these symptoms last 3-4 days 10/06/2018 41 Giardiasis Prof. Dr. Saad S Al Ani Explosive watery diarrhea Vomiting Abdominal cramps Fever Foul flatus Malaise

42. Gastrointestinal manifestations (Cont.) Subacute syndrome ( More common) After the symptoms of abrupt onset Most patients experience a more insidious onset of symptoms, which are recurrent or resistant . Stools become malodorous , mushy , and greasy Watery diarrhea may alternate with soft stools or even constipation 10/06/2018 42 Giardiasis Prof. Dr. Saad S Al Ani

43. Upper GI symptoms: often exacerbated by eating accompany stool changes may be present in the absence of soft stools. These include: upper and midabdominal cramping nausea early satiety bloating substernal burning acid indigestion. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 43 Gastrointestinal manifestations (Cont.)

44. Constitutional symptoms Anorexia, fatigue, malaise, and weight loss are common Weight loss occurs in more than 50% of patients Chronic illness may occur Adults may present with long-standing malabsorption syndrome children may present with failure to thrive 10/06/2018 44 Giardiasis Prof. Dr. Saad S Al Ani

45. Extraintestinal manifestations Are rare I nclude allergic manifestations such as: Urticaria Erythema multiforme Bronchospasm Reactive arthritis Biliary tract disease The etiology is likely a result of : H ost immune system activation C ross-reactivity/molecular mimicry . 10/06/2018 45 Giardiasis Prof. Dr. Saad S Al Ani

46. Symptoms of chronic infection 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 46 Symptoms of chronic infection Malaise Weight loss (~66% of symptomatic patients) Nausea Post infection lactase deficiency (2-40% of cases) Anorexia Chronic diarrhea

47. Physical Examination Physical examination does not contribute to the diagnosis of giardiasis Weight loss may be evident No known unique physical findings are attributable to giardiasis . 10/06/2018 47 Giardiasis Prof. Dr. Saad S Al Ani

48. Physical Examination (Cont.) On abdominal examination, patients may have nonspecific tenderness without evidence of peritoneal irritation Rectal examination should reveal heme-negative stools In severe cases, evidence of dehydration or wasting may be present . 10/06/2018 48 Giardiasis Prof. Dr. Saad S Al Ani

49. Complications of giardiasis May include the following: Development of chronic illness with weight loss Malabsorption syndrome in adults Failure to thrive in children Disaccharidase deficiency Zinc deficiency in schoolchildren   1 Growth retardation   2 Persistent gastrointestinal symptoms 3 10/06/2018 49 Giardiasis Prof. Dr. Saad S Al Ani 1.Quihui L, Morales GG, Mendez RO, Leyva JG, Esparza J, Valencia ME. Could giardiasis be a risk factor for low zinc status in schoolchildren from northwestern Mexico? A cross-sectional study with longitudinal follow-up.  BMC Public Health . 2010 Feb 20. 10(1):85 . 2.Pickering LK. Giardia lamblia (Giardiasis). Long SS.  Principles and Practice of Pediatric Infectious Diseases . 3rd ed. Philadelphia, PA: Churchill Livingstone An imprint of Elsevier Inc ; 2008. 265: 1241-1245 . 3.Ouattara M, N'guessan NA, Yapi A, N'goran EK. Prevalence and spatial distribution of Entamoeba histolytica / dispar and Giardia lamblia among schoolchildren in Agboville area (Côte d'Ivoire).  PLoS Negl Trop Dis . 2010 Jan 19. 4(1):e574.

50. The diagnosis Stool examination   Ideally , 3 specimens from different days should be examined because of potential variations in fecal excretion of cysts .  G intestinalis  is identified in 50-70% of patients after a single stool examination and in more than 90% after 3 stool examinations. Stool ova and parasite (O&P) examination  aids in the diagnosis of giardiasis in 80-85% of patients Nagaty IM, Hegazi MM. Dot-ELISA copro -antigen and direct stool examination in diagnosis of giardiasis patients.  J Egypt Soc Parasitol . 2007 Aug. 37(2):641-8 . 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 50

51. The diagnosis (Cont.) Stool antigen enzyme-linked immunosorbent assays These tests are best used as a screening test in high-incidence settings such as: Day-care centers For identification of subjects during an epidemic, They should not take the place of stool microscopy . Nagaty IM, Hegazi MM. Dot-ELISA copro -antigen and direct stool examination in diagnosis of giardiasis patients.  J Egypt Soc Parasitol . 2007 Aug. 37(2):641-8. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 51

52. The diagnosis (Cont.) Stool antigen enzyme-linked immunosorbent assay ( ELISA ) may be helpful , If the results from 3 O&P tests are negative and giardiasis is still suspected Upper endoscopy with biopsies and duodenal aspirate is a reasonable alternative Nagaty IM, Hegazi MM. Dot-ELISA copro -antigen and direct stool examination in diagnosis of giardiasis patients.  J Egypt Soc Parasitol . 2007 Aug. 37(2):641-8. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 52

53. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 53 Differential diagnoses of Giardiasis Amebiasis Food poisoning Sprue Crohn disease Irritable bowel syndrome Strongyloidiasis Cryptosporidiosis Lactose intolerance Viral gastroenteritis

54. Treatment Generally, do not treat asymptomatic persons who excrete the organism, except to : Prevent household transmission( e.g., from toddlers to pregnant women or to patients with hypogammaglobulinemia or cystic fibrosis) Permit adequate treatment in individuals with possible  Giardia intestinalis  –associated antibiotic malabsorption who require oral antibiotic treatment for other infections 10/06/2018 54 Giardiasis Prof. Dr. Saad S Al Ani Kiser JD, Paulson CP, Brown C. Clinical inquiries. What's the most effective treatment for giardiasis?.  J Fam Pract . 2008 Apr. 57(4):270-2

55. Treatment Metronidazole is the most commonly prescribed antibiotic for this condition Appropriate fluid and electrolyte management is critical, particularly in patients with large-volume diarrheal losses 10/06/2018 55 Giardiasis Prof. Dr. Saad S Al Ani Abdul-Wahid A, Faubert G. Characterization of the local immune response to cyst antigens during the acute and elimination phases of primary murine giardiasis.  Int J Parasitol . 2008 May. 38(6):691-703. 

56. Prognosis The prognosis for patients with giardiasis is generally excellent . Most patients are asymptomatic Most infections are self-limited. Giardiasis is not associated with mortality except in rare cases of extreme dehydration , primarily in infants or malnourished children . 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 56

57. Prevention Careful hand washing Infected persons and persons at risk should carefully wash their hands after they have any contact with feces Careful hand washing is important, especially for caregivers of diapered infants in day-care centers 10/06/2018 57 Giardiasis Prof. Dr. Saad S Al Ani

58. 10/06/2018 Giardiasis Prof. Dr. Saad S Al Ani 58 https:// paperlust.co