WBR0406
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Microbiology |
| Sub Category | SubCategory::Gastrointestinal |
| Prompt | [[Prompt::A 25 year old Caucasian male patient presents to the emergency department with bloody diarrhea. He recently arrived to USA from an underprivileged town abroad. Following initial work-up, further investigations reveal multiple flask-shaped ulcers with grey-colored base around the colonic mucosa. Stool analysis and examination reveal the following organism as seen in the image below. What is the best available treatment for this patient?]] |
| Answer A | AnswerA::Suramin and melarsoprol |
| Answer A Explanation | AnswerAExp::Suramin, melasoprol, and eflornithin are used for treatment of African sleeping sickness that is caused by Trypanosoma brucei and transmitted by Tse Tse fly bite |
| Answer B | AnswerB::Amphotericin B |
| Answer B Explanation | AnswerBExp::Amphotericin B is an antifungal that is helpful in treating systemic mycoses. |
| Answer C | AnswerC::Sulfadiazine and pyrimethamine |
| Answer C Explanation | AnswerCExp::Sulfadiazine and pyrimethamine are treatment options for Toxoplasmia gondii. |
| Answer D | AnswerD::Atovaquone and azithromycin |
| Answer D Explanation | AnswerDExp::Atovaquone and azithromycin are treatment options for Babesia. |
| Answer E | AnswerE::Metronidazole |
| Answer E Explanation | AnswerEExp::Metronidazole is the treatment of choice for E. histolytica. |
| Right Answer | RightAnswer::E |
| Explanation | [[Explanation::Entamoeba histolytica is a parasite that causes bloody diarrhea. E. histolytica is usually seen in regions with poor sanitation. Cysts are able to survive in food, in water, and on land. Cysts are swallowed. The pathogenic trophozoite stage develops in the GI tract and exists only in the host and in feces. E. histolytica causes characteristic colonic flask-shaped ulcers. E. histolytica infections can be complicated by formation of liver abscess, called “amebic liver abscess” that has an “anchovy paste” exudate. Treatment for E. histolytica dysentery is metronidazole.
Educational Objective: Entamoeba histolytica is a parasite that causes dysentery. It is common in areas with poor sanitation. It causes typical flask-shaped ulcer in colonic mucosa. First line treatment for E. histolytica dysentery is metronidazole. Reference:
Pritt BS, Clark CG. Amebiasis. Mayo Clinic Proceedings. 2008;83(10):1154-1160. |
| Approved | Approved::No |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |