An ultramicroscopic study of skin and conjunctival biopsies in chronic neurological disorders of childhood.

One hundred twenty-seven skin and 59 conjunctival biopsies were performed in 136 pediatric patients with chronic neurological disorders. Ultrastructural abnormalities were found in 48 of 72 patients with unequivocally progressive encephalopathies (67 of which could not be diagnosed by biochemical means) and in 4 patients with miscellaneous disease (fetal rubella syndrome and hereditary motor-sensory neuropathy), but in none of 55 patients with static or dubiously progressive encephalopathies. Of the 48 positive biopsies in the group with progressive encephalopathies, 39 showed abnormalities characteristic enough to permit a specific diagnosis (lysosomal storage disorders, neuroaxonal dystrophy, ophthalmoplegia-plus) in conjunction with a compatible clinical picture. In 9 cases no diagnosis could be made despite the finding of lamellar or vacuolar inclusions. In no case were discrepancies observed between the results of skin and conjunctival biopsies. Although biochemical analysis is the simplest and most effective technique for the diagnosis of most progressive encephalopathies, skin or conjunctival biopsy is a valuable procedure in patients without detectable enzyme deficiency.