WBR0291
| Author | [[PageAuthor::Ogheneochuko Ajari, MB.BS, MS [1] (Reviewed by Yazan Daaboul, M.D.)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Microbiology, MainCategory::Pathophysiology |
| Sub Category | SubCategory::General Principles, SubCategory::Infectious Disease |
| Prompt | [[Prompt::A 28-year-old woman presents to the physician's office with complaints of fever, sore throat, and swelling in her axilla. Her temperature is 38.3 °C (101 °F), her blood pressure is 136/86 mmHg, and her heart rate is 100/min. Physical examination is remarkable for axillary lymphadenopathy. A throat swab is performed and sent for culture. Two days later, a gram-positive club-shaped rod that contains metachromatic granules forms black colonies on tellurite agar. What is the mechanism of virulence that characterizes the organism responsible for this patient's condition?]] |
| Answer A | AnswerA::It binds to MHC II and T-cell receptor, resulting in polyclonal T-cell activation |
| Answer A Explanation | AnswerAExp:: |
| Answer B | AnswerB::It acts via antibodies to M proteins to enhance the host defenses |
| Answer B Explanation | AnswerBExp:: |
| Answer C | AnswerC::It inhibits protein synthesis via ADP ribosylation of EF-2 |
| Answer C Explanation | AnswerCExp:: |
| Answer D | AnswerD::It blocks GABA and glycine release from cells in the spinal cord |
| Answer D Explanation | AnswerDExp:: |
| Answer E | AnswerE::It produces catalase to degrade hydrogen peroxide |
| Answer E Explanation | AnswerEExp:: |
| Right Answer | RightAnswer::C |
| Explanation | [[Explanation:: Educational Objective: |
| Approved | Approved::Yes |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |