New findings in a patient with I-cell disease

A case of I-cell disease showing some previously undescribed features is reported. The diagnosis was confirmed on the basis of lysosomal enzyme activity. The radiogram showed metaphyseal radiolucent bands not yet described and extensive epiphyseal stippling. The electronmicroscopical findings clearly demonstrated the presence of abnormal inclusion bodies in absorptive cells and in cells of the lamina propria of the small intestine. Immunological investigation revealed and increased absolute number of both B and T lymphocytes. The B cells, unlike the T cells, showed cytoplasmic vacuoles on phase contrast microscopy. The immune response to antigenic challenge was impaired, as assessed by specific antibody production and in vitro lymphocyte transformation testing.