<unk>  is a cause of recurrent kidney stones. 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. Upon removal, the stones may be pink or yellow in color, but later they turn to greenish due to exposure to air.<unk>  is usually asymptomatic when no stone is formed. However, once a stone is formed, signs and symptoms can occur: * Nausea * Flank pain * Hematuria * Urinary tract infections * Rarely, acute or chronic kidney disease People with<unk>  pass stones monthly, weekly, or daily, and need ongoing care.<unk> s have an increased risk for chronic kidney disease and since kidney damage or poor function is often present in<unk> s, the use of nonsteroidal anti-inflammatory drugs (NSAIDs) or over the counter (OTC) medications should be used with caution. Cystine stones are often difficult to detect using plain x-rays. Computed tomography or ultrasound may be used instead for imaging. Urine odor in<unk>  has a smell of rotten eggs due to the increase in cystine.
Cystinuria
Xanthinuria
Aminoaciduria
Uricosuria
Iminoglycinuria
Hyperuricosuria
Renal glycosuria
Lipiduria