WBR0204
| Author | PageAuthor::William J Gibson |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Microbiology, MainCategory::Pathophysiology |
| Sub Category | |
| Prompt | [[Prompt::A 45 year old HIV positive man presents to your office complaining of increasing fatigue, difficulty swallowing and 15 lb weight loss in the past 2 months. His CD4+ count is 200, viral load is 50,000. Physical exam reveals a white patch on the right side of the tongue which cannot be scraped off. What is the most likely causal organism?]] |
| Answer A | AnswerA::Candida Albicans |
| Answer A Explanation | AnswerAExp::'''Incorrect''' - Candida Albicans is responsible for thrush, which is distinct from hairy leukoplakia. Thrush can be mechanically disturbed by scraping with tongue depressor whereas hairy leukoplakia cannot. |
| Answer B | AnswerB::HHV-8 |
| Answer B Explanation | AnswerBExp::'''Incorrect''' - HHV-8 is thought to cause Kaposi Sarcoma in AIDS patients |
| Answer C | AnswerC::EBV |
| Answer C Explanation | AnswerCExp::'''Correct''' - See explanation |
| Answer D | AnswerD::Cryptococcus |
| Answer D Explanation | [[AnswerDExp::Incorrect - Cryptococcus causes meningitis in HIV infected patients with low CD4 (<100).]] |
| Answer E | AnswerE::CMV |
| Answer E Explanation | [[AnswerEExp::Incorrect - CMV causes retinitis in HIV infected patients, typically when CD4 < 50.]] |
| Right Answer | RightAnswer::C |
| Explanation | [[Explanation::The patient in this vignette is suffering from hairy leukoplakia, a white patch on the side of the tongue with a corrugated or hairy appearance. Hairy leukoplakia can be distinguished from oral candidiasis by the fact that candidiasis causes lesions which can be sloughed off by scraping whereas leukoplakia cannot. Hairy leukoplakia is caused by Epstein-Barr virus in HIV infected patients. As a benign lesion, it does not require treatment but typically responds to acyclovir. The presence of hairy leukoplakia may indicate a high degree of severity of the patients immunocompromisation.
Educational Objective: Hairy Leukoplakia in HIV patients is caused by EBV. References: First Aid 2012 page 194 |
| Approved | Approved::Yes |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |