Intracellular killing and digestion of phagocytosed pathogen is the last but most important step in the function of phagocytes but, in patients with chronic granulomatus diseases intracellular killing does not take place due to a defective gene.

In 70% of patients the culprit is X-linked gene but in others an autosomal recessive gene is responsible.

Chronic granulomatous disease is characterized by white blood cells (WBCs) that cannot produce activated 02 compounds and defective microbicidal function of phagocytes. Manifestations include recurrent infections; multiple granulomatous lesions of the lungs, liver, lymph nodes, gastro intestinal and urinogenital tracts; abscesses; lymphadenitis; hypergammaglobulinemia; elevated erythrocyte sedimentation rate (ESR); and anemia.

More than 50% of cases of chronic granulomatous disease (CGD) are inherited as an X-linked recessive trait and thus occur only in males; in the rest, inheritance is autosomal recessive.