Definition: deficiency of superoxide production by polymorphonuclear neutrophils and macrophages

Etiology

X-linked recessive or autosomal recessive inheritance (2:1)

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Pathophysiology

Defective phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase that results in:

• Impaired respiratory burst & ↓ reactive oxygen species → inhibition of phagocytic intracellular killing

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Clinical features

• Recurrent, severe infections (chronic skin, lymph node, bone, respiratory, GI, and urinary tract infections) with catalase-positive organisms
  • Staphylococcus aureus
  • Burkholderia cepacia
  • Serratia marcescens
  • Nocardia
  • Aspergillus
• Lymphadenopathy
• Granulomas of the skin and GI/GU tract

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Diagnostics

• Neutrophil assay
  • Dihydrorhodamine test (DHR): flow cytometry test showing abnormal NADPH oxidase activity (inability to metabolize dihydrorhodamine to fluorescent product, rhodamine → decreased green fluorescence)
• Nitroblue tetrazolium dye reduction test: negative

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Treatment

• Life-long prophylactic antibiotics, e.g., TMP-SMX (for catalase-positive infections)
• IFN-γ therapy
• Bone marrow transplant

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