Immunology USMLE Step 1 Practice Question
A 7 year old boy is seen for recurrent skin abscesses and repeated episodes of pneumonia. His parents say the abscesses are not very red or tender. He has chronic eczema and coarse facies. Laboratory studies show eosinophilia and markedly elevated IgE. Which of the following defects is most likely responsible?
Answer choices
- ADefective Th17 cell differentiationCorrect answer
- BDeficient C5 through C9 membrane attack complex formation
- CAbsent B cell maturation in bone marrow
- DFailure of neutrophils to adhere to endothelium
- EDefective phagolysosome fusion
- FImpaired interferon-gamma production by T cells
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