Central nervous system involvement in nephropathic cystinosis.

Nephropathic cystinosis, an autosomal recessive lysosomal storage disorder due to impaired cystine transport, causes damage to multiple organs that results in end-stage renal disease, hypothyroidism, and retinopathy, usually in childhood. Dialysis and renal transplantation now frequently enable patients with cystinosis to live into adulthood. Examinations at autopsy of a 28-year-old man who died of complications of this disease showed deposits of cystine crystals in multiple organs. There was severe cerebral involvement with multifocal cystic necrosis, dystrophic calcification, spongy change, and vacuolization that had produced profound neurologic deficits. Electron microscopy of the brain documented cytoplasmic deposition of cystine crystals in membrane bound vacuoles within the cytoplasm of pericytes and within parenchymal cells of the white matter. While affected patients who have received renal transplants may no longer die from renal failure, serious, potentially life-threatening, neurologic complications of this disorder may supervene.