CYSTINURIA is intrinsically a nonfatal metabolic abnormality with variable morbidity. The morbidity associated with this disorder is directly related to the relative insolubility of cystine and the resulting formation of cystine stones in the urinary tract. Since concurrent chronic disease has rarely been reported in association with cystinuria, it seemed appropriate to record observations on four of six cystinuric patients who had hyperuricemia, normal renal function, and family backgrounds of hyperuricemia. These six cases of cystinuria comprise our experience with the disease.
Methods and Materials
The cyanide nitroprusside test1 was used to test for urinary cystine. Urinary two-dimensional thinlayer chromatograms for amino acids, modified from Fahmy et al,2 were examined for the presence of lysine, cystine, arginine, and ornithine. Serum and urinary uric acid were measured by the uricase method of Liddle et al. By this method, any value over 6.5 mg/100 ml indicates hyperuricemia.3 The families
Meloni CR, Canary JJ. Cystinuria With Hyperuricemia. JAMA. 1967;200(3):257–259. doi:10.1001/jama.1967.03120160123029