Letter to the Editor

In a recent issue of Archives of Iranian Medicine, Ayatollahi et al reported the effectiveness of nitroblue tetrazolium (NBT) test in the diagnosis of chronic granulomatous disease (CGD). The authors emphasized the usefulness of phorbol myristate acetate (PMA)-stimulated NBT method for detection of carriers and prenatal diagnosis of CGD as well. We do not agree with the authors that NBT method can detect carriers of CGD. CGD is always a heterogeneous genetic disease caused by a large variety of mutations, located in four genes. Typical CGD cases are transmitted by an X-linked recessive pattern caused by the absence of cytochrome b 558 heavy chain (gp91-phox), a component of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex located on Xp21. The rest of the cases are inherited by autosomal recessive mechanisms and are caused by the absence of cytochrome b 558 light chain (p22-phox) or one of the two cytosolic factors (p47-phox or p67-phox) necessary for NADPH oxidase activation.