Griscelli syndrome.

A 4-month-old child had silvery gray hair, light-colored skin, recurrent chest infections, hepatosplenomegaly, and episodes of pancytopenia and hemophagocytosis in the liver, spleen, and bone marrow. Light microscopy of hair showed characteristic large aggregates of pigment granules distributed irregularly along the hair shaft. Peripheral blood smear examination did not show giant granules in granulocytes. Enlarged hyperpigmented basal melanocytes with sparsely pigmented adjacent keratinocytes were seen on the skin biopsy specimen. On the basis of these clinical and laboratory findings, Griscelli syndrome was diagnosed. The child succumbed to infection during an accelerated phase of the disease.