A Novel Mutation Of The Cybb Gene Resulting In Severe Form Of X-Linked Chronic Granulomatous Disease

We evaluated a boy who had multiple Salmonella septicemia, Aspergillus pneumonia and brain abscesses. His nitroblue tetrazolium (NBT) test was reportedly abnormal. The Dihydrorhodamine (DHR) flow cytometry assay was compatible with typical X-linked chronic granulomatous disease (X-CGD). CYBB analysis revealed a novel complex mutation atggacg -> ttca in exon 12 (base pairs 1532-1538). As a result, 3 amino acids Tyr 511, Gly 512 and Arg 513 were deleted and replaced by 2 amino acids, Phe and Gln. The DHR and mutation analysis of his mother showed normal DHR pattern and no mutations in exon 12 of CYBB gene. In conclusion, any children with multiple Salmonella and Aspergillus infection should be suspected of CGD. NBT test, DHR assay and gene analysis are helpful tools to confirm the diagnosis even in the case of de novo mutation.