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1. Anatomy
2. Microbiology
2.1 General bacteriology
2.2 Introduction to systemic bacteriology
2.3 Gram positive cocci
2.4 Gram negative cocci
2.5 Gram positive bacilli
2.6 Gram negative bacilli
2.7 Other important bacteria
2.8 Virology
2.9 Parasitology
2.9.1 Entamoeba histolytica
2.9.2 Acanthamoeba
2.9.3 Naegleria fowleri
2.9.4 Giardia lamblia
2.9.5 Cryptosporidium parvum
2.9.6 Trichomonas
2.9.7 Plasmodium spp.
2.9.8 Babesia
2.9.9 Toxoplasma gondii
2.9.10 Taenia
2.9.11 Hymenolepis nana
2.9.12 Enterobius vermicularis
2.9.13 Trichuris
2.9.14 Trichinella
2.9.15 Ascaris
2.9.16 Hookworms
2.9.17 Strongyloides
2.9.18 Additional information
2.10 Mycology
3. Physiology
4. Pathology
5. Pharmacology
6. Immunology
7. Biochemistry
8. Cell and molecular biology
9. Biostatistics and epidemiology
10. Genetics
11. Behavioral science
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2.9.4 Giardia lamblia
Achievable USMLE/1
2. Microbiology
2.9. Parasitology

Giardia lamblia

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Giardia lamblia

Infection is transmitted by ingestion of food or water contaminated with cysts. Cysts are relatively resistant to chlorination especially in cold waters. It presents as diarrhea, gas, greasy stools that tend to float , abdominal cramps, nausea, vomiting and dehydration. It may lead to weight loss and failure to absorb fat, lactose, vitamin A and vitamin B12, itchy skin, hives, and swelling of the eye and joints. For diagnosis. Fecal immunoassays are preferred. Stool microscopy shows motile trophozoites with “falling leaf” motility. Cysts can be seen in stool specimens after concentration techniques. String test or enterotest can be used to diagnose trophozoites in bile. Antigen detection is done by ELISA and direct immunofluorescence. Antibody detection is done by ELISA and indirect immunofluorescence.

Giardia lamblia also called duodenalis
Giardia lamblia also called duodenalis

G. duodenalis trophozoites in Kohn stain.

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