Mycology/Parasitology USMLE Step 1 Practice Question
A 7-year-old boy from Ghana presents with nodules on his shins, back, and elbows. He also complains of nerve pain along his forearms. Examination reveals areas of decreased sensation over his arms and legs. Nerve biopsy reveals acid-fast bacilli. Which of the following best describes the immunological basis for his cutaneous manifestations?
Answer choices
- AType I hypersensitivity with mast cell activation
- BType III hypersensitivity with immune complex deposition
- CComplement-mediated alternative pathway activation
- DType II hypersensitivity with antibody-mediated cytotoxicity
- EType IV hypersensitivity reaction with granuloma formationCorrect answer
- FType I hypersensitivity with release of histamine from basophils
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