Agenesis of the corpus callosum, combined immunodeficiency, bilateral cataract, and hypopigmentation in two brothers.

We describe 2 brothers with a malformation syndrome consisting of agenesis of the corpus callosum, cutaneous hypopigmentation, bilateral cataract, cleft lip and palate, and combined immunodeficiency. The clinical history of both patients was characterized by severe psychomotor retardation, seizures, recurrent severe respiratory infections, and chronic mucocutaneous candidiasis. The children died of bronchopneumonia at age 2 and 3 years, respectively. Immunological investigations showed, in one sib studied, skin anergy to recall antigens, profound depletion of T4+ lymphocytes, and serum IgG2 deficiency. Necropsy showed agenesis of the corpus callosum, hypoplasia of the cerebellar vermis, and profound hypoplasia of the thymus and of the peripheral lymphoid tissue. The distinctive features of these sibs appear to define a previously undescribed hereditary MCA/MR syndrome. The clinical and pathological findings seem to indicate, as a pathogenetic mechanism, a defect involving the embryonic organization of the central nervous system and of the immune system.