Macrothrombocytopenia and progressive deafness: a new genetic syndrome.

We report a kindred with hereditary macrothrombocytopenia and progressive sensorineural hearing loss. Although the occurrence of hereditary sensorineural hearing loss associated with macrothrombocytopenia has been reported in a small number of families, varying degrees of renal pathology have always been present. In contrast to the previously reported syndromes involving a giant-platelet disorder and deafness, none of the family members in this report have had any evidence of renal dysfunction. The disorder was inherited in a linear pattern from great-grandmother to grandmother to mother to daughter. The clinical manifestations include hearing impairment that begins before the third decade and progresses to severe to profound bilateral hearing loss by the fourth decade. The platelet disorder manifests in early childhood and persists lifelong, although it tends to remain subclinical. Hematologic and ultrastructural findings will be contrasted to those found in Alport syndrome.