Background
- Primary immunodeficiency of neutrophils leading to recurrent infections with catalase-positive organisms
Pathophysiology
- Defect in NADPH oxidase
- Therefore unable to generate superoxide radicals required by phagocytes to kill pathogens
Clinical Manifestations
- Recurrent infections
- Catalase-positive organisms, including Staphylococcus aureus, Burkholderia cepacia, Serratia marcescens, Nocardia, and Aspergillus
- CGD is the highest-risk group for invasive aspergillosis
- Granuloma formation, often in the GI and GU tracts and may precede other clinical symptoms
Differential Diagnosis
- Other primary immunodeficiencies
- MPO deficiency, which will have an abnormal DHR test but largely asymptomatic unless concurrent diabetes mellitus
- Hyper-IgE syndrome, though Aspergillus will be more typically pulmonary
- IRAK4/MyD88 deficiency, which won't have fungal infections and improves with age
- Humoral immunodeficiencies, such as CVID or Bruton tyrosine kinase deficiency, though they tend to have more infections with encapsulated organisms and will have abnormal quantitative immunoglobulins
- Inflammatory bowel disease
- Cystic fibrosis
- Sarcoidosis, which will cause granuloma formation but shouldn't increase risk of infection
Diagnosis
- The diagnosis is confirmed with the dihydrohodamine-123 (DHR-123) test
Management
- Treat intercurrent infections
- Prophylaxis with:
- TMP-SMX
- Itraconazole
- Possibly also interferon-γ
Further Reading
- Considerations in the Diagnosis of Chronic Granulomatous Disease. J Pediatric Infect Dis Soc. 2018;7(S1):S6-S11. doi: 10.1093/jpids/piy007
