I-cell disease: report of a case.

I-cell disease, or mucolipidosis type II (ML II), resembles Hurler syndrome but without the mucopolysacchariduria. I-cell disease is a slowly progressive disorder with onset at birth and fatal outcome in childhood. The neonate with I-cell disease usually has a low birth weight. Unlike Hurler syndrome, there is no temporary acceleration of skeletal growth around one year of age. Instead, clinical characteristics included coarse face and skin, skeletal abnormalities, gum hypertrophy, and severe psychomotor retardation. Head size is proportional to stature. Psychomotor retardation is extreme in some patients but rather mild in others. The most frequent causes of death are bronchopneumonia and congestive heart failure. We report a 9 month-old male infant with characteristic clinical features of I-cell disease. Cytoplasmic inclusions were observed in cultured skin fibroblasts. Ultrastructural study of normal looking skin revealed numerous cytoplasmic inclusions with pleomorphic contents in the fibroblasts and Schwann cells. The diagnosis was confirmed by lysosomal enzyme assay in serum and fibroblasts.