Update on nephropathic cystinosis
- 1 January 1990
- journal article
- review article
- Published by Springer Science and Business Media LLC in Pediatric Nephrology
- Vol. 4 (6), 645-653
- https://doi.org/10.1007/bf00858644
Abstract
The cystine that accumulates within cystinotic lysosomes comes primarily from proteins which have been degraded within this organelle. The individual amino acids have specific transport mechanisms to exit the lysosome. The lysosomal cystine transporter is defective in all types of cystinosis. When cells from patients with nephropathic and benign cystinosis were fused, the defect was not corrected and the cystine level remained elevated. This strongly indicates that the genetic defects are allelic (i.e., on the same chromosome). Cysteamine is a weak base which enters the cystinotic lysosome and reacts with cystine forming a mixed disulfide of half-cystine and cysteamine. This mixed disulfide rapidly exits the lysosome via the transport system for cationic amino acids which is normal in cystinosis. Because of the success of renal transplantation, many cystinosis patients are alive in their twenties and even early thirties. Unfortunately, these patients have developed damage to other organs including thyroid, eye, central nervous system, pancreas, and muscle. Cysteamine and its analog, phosphocysteamine, are very beneficial to cystinosis patients, especially when started early in life. These drugs may prevent the need for transplantation. It is too early to know if they will prevent damage to other organs.Keywords
This publication has 97 references indexed in Scilit:
- Description of a selection method highly cytotoxic for cystinotic fibroblasts but not normal human fibroblastsSomatic Cell and Molecular Genetics, 1992
- Neurologic and cognitive deficits in children with cystinosisThe Journal of Pediatrics, 1988
- Pancreatic exocrine insufficiency in a patient with nephropathic cystinosisThe Journal of Pediatrics, 1988
- Course of nephropathic cystinosis after age 10 yearsThe Journal of Pediatrics, 1986
- Renal failure in a sibship with late-onset cystinosisThe Journal of Pediatrics, 1985
- Decreased sweat production in cystinosisThe Journal of Pediatrics, 1984
- Veno-occlusive disease of the liver associated withcysteamine treatment of nephropathic cystinosisThe Journal of Pediatrics, 1983
- Cystine depletion of cystinotic tissues by phosphocysteamine (WR638)The Journal of Pediatrics, 1980
- Endocrine studies in cystinosis: Compensated primary hypothyroidismThe Journal of Pediatrics, 1977
- The early diagnosis of cystinosisThe Journal of Pediatrics, 1969