Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 3-year-old boy presents with recurrent pyogenic infections caused by Staphylococcus aureus and Streptococcus pneumoniae. On examination, he has a chronic boil on his arm (BP 95/60, HR 110, RR 24, Temp 37.8°C) that fails to form purulent drainage. Laboratory studies show normal neutrophil counts (7,500/μL) and normal phagocytosis, but impaired oxidative burst on dihydrorhodamine flow cytometry. No lymphadenopathy is noted. Which diagnosis best explains these findings?
Answer choices
- AChronic granulomatous diseaseCorrect answer
- BCommon variable immunodeficiency
- CLeukocyte adhesion deficiency
- DMyeloperoxidase deficiency
- EDiGeorge syndrome with T-cell deficiency
- FX-linked agammaglobulinemia
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