Giardia lamblia is an intestinal parasite with two stages - the trophozoite stage which inhabits the small intestine, and the cyst stage which is excreted and can contaminate water and food. It causes giardiasis through the fecal-oral route. Symptoms include diarrhea, abdominal pain and cramps. Diagnosis involves examining stool samples microscopically for trophozoites or cysts. Treatment typically involves metronidazole antibiotics for 5-10 days to eradicate the parasite in over 85% of cases. Prevention focuses on proper hygiene and water treatment to avoid contamination.

1. Giardia lamblia Dr Kamran Afzal Classified Microbiologist

8. LIFE CYCLE of Giardia lamblia Trophozoites Trophozoites Cysts Mature Cysts Duodenum, upper ileum, gall bladder The lower portion of ileum or colon Contaminated water and food Stool Multiplied by binary fission Diarrhea Outside Outside

11. Trophozoites are attached to the mucosal surface by sucker, reproduced by binary fission Diarrhea, abdominal pain, bloating, nausea, and vomiting Mechanical blockage of the intestinal mucosa, competition for nutrients, inflammation Histology: shortening of microvilli, elongation of crypts, and damaging the brush border of the absorptive cells G. lamblia inhabits the duodenum, jejunum and upper ileum PATHOGENESIS

20. Entamoeba histolytica

28. LIFE CYCLE CYST Ingestion by humans Excystation in small intestine Encystation in colon Excretion in faeces TROPHOZOITE Asymptomatic colonization Amoebic colitis Liver abscess

34. Colitis is the most common form of disease associated with amoebae

35. Ulceration can lead to secondary infection and extraintestinal lesions

36. Extraintestinal amoebiasis

37. Amoebic liver abscess

43. HISTOPATHOLOGY