WBR0703
| Author | [[PageAuthor::Mohamed Moubarak, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 3 |
| Main Category | MainCategory::Emergency Room |
| Sub Category | SubCategory::Infectious Disease |
| Prompt | [[Prompt::19 year old boy present to the ER with generalized rash, he had fever and sore throat one week ago and got antibiotic prescription from his primary care physician 4 days ago. His past medical history is insignificant. He doesn’t smoke or consume recreational drugs or alcohol. He is sexually active with one partner and uses condoms regularly. Vital signs are normal except for temperature of 37.8 C(100 F). His physical examination reveals generalized maculopapular rash and posterior cervical lymphadenopathy. What is the most likely mechanism of rash development in that patient?]] |
| Answer A | AnswerA::Familial |
| Answer A Explanation | [[AnswerAExp::Incorrect
Rash to ampicillin doesn’t represent familial predisposition]] |
| Answer B | AnswerB::Viral exanthema |
| Answer B Explanation | [[AnswerBExp::Incorrect
Viral exanthema usually observed during active viral infections]] |
| Answer C | AnswerC::Immediate hypersensitivity |
| Answer C Explanation | [[AnswerCExp::Incorrect
The rash doesn’t represent immediate hypersensitivity to ampicilline]] |
| Answer D | AnswerD::Delayed hypersensitivity |
| Answer D Explanation | [[AnswerDExp::Incorrect
The rash doesn’t represent delayed hypersensitivity to ampicilline]] |
| Answer E | AnswerE::Immune complexes |
| Answer E Explanation | [[AnswerEExp::Correct
Circulating IgG and IgM antibodies targeting penicillin derivatives is the cause of the well known ampicilline-associated maculopapular rash phenomenon in patients with infectious mononucleosis]] |
| Right Answer | RightAnswer::E |
| Explanation | [[Explanation::Ampicilline-associated maculopapular rash in patients with infectious mononucleosis is a well know phenomenon. It is caused by the circulating IgG and IgM targeting penicillin derivatives causing this immune vasculitic rash Educational Objective: |
| Approved | Approved::No |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |