intermediate cystinosis

Intermediate cystinosis is a genetic disorder characterized by the accumulation of cystine crystals in body tissues, typically manifesting in adolescence. This condition results from a mutation in the CTNS gene, which impairs the transport of cystine out of cellular lysosomes. While similar to the more severe nephropathic form, intermediate cystinosis progresses more slowly, with kidney failure usually occurring between ages 15 and 25. Diagnosis involves genetic testing, detection of cystine crystals in the cornea, and elevated cystine levels in cells. Treatment focuses on depleting cystine with agents like cysteamine, though renal damage is irreversible, and some patients may require dialysis or transplantation.1