Macrophage Activation Syndrome as a Complication of Chronic Granulomatous Disease: A Case Report.

Chronic granulomatous disease (CGD) presents with granuloma formation and lethal infections. It is inherited in an autosomal or X-linked recessive pattern. We describe a 10-month-old patient with a fatal secondary HLH as a CGD primary manifestation. We carried out an autopsy and found noncaseating granulomas, an aspergilloma in the lung, and hemophagocytosis. We performed a DHR assay on the patient's mother and grandmother, showing a bimodal pattern conclusive of X-linked CGD. Thus, our definitive diagnosis was CGD complicated by macrophage activation syndrome. CGD is caused by phagocytes' inability to control pathogens, resulting in granulomas. Secondary HLH is a severe complication and could be characterized by the proliferation of macrophages and T lymphocytes and the production of proinflammatory cytokines. The early suspicion of this presentation helps establish a specific treatment, and the study of the carriers helps determine the etiology.