It is a disease involving the defective transepithelial transport of cystine and dibasic amino acids in the kidney and intestine, and is one of many causes of
kidney stones. If not treated properly, the disease could cause serious damage to the
kidneys and surrounding organs, and in some rare cases death. The stones may be identified by a positive nitroprusside cyanide test. The crystals are usually hexagonal, translucent, white.