A 5-year-old girl is brought to the physician by her mother for a 2-day history of headache and fever. She has history of recurrent otitis media and urinary tract infections, as well as skin infections caused by S. aureus and Candida. Laboratory studies show a delay of segmented neutrophil bactericidal activity against S. aureus, with marked impairment against Candida. This patient most likely has homozygous mutations coding for which of the following?
CD40L
LFA-1/CD18 integrin
Myeloperoxidase
NADPH oxidase
Tyrosine kinase
