Adult cystinosis—A benign disorder

Abstract Cystinosis is described in a fifty year old woman and two of her brothers. Crystals were found in her peripheral leukocytes, cornea and bone marrow, and proved in the latter tissue to be cystine by their x-ray diffraction pattern. Crystals were also present in the corneas of two of her brothers, one of whom showed crystals in the bone marrow as well. In striking contrast to childhood cystinosis no evidence of renal dysfunction or renal damage was associated with the cystine deposition. In fact, adult cystinosis appears to be a benign disorder. A recessive mode of inheritance for this disorder is further supported by the consanguinity of the parents.