M. Francisca García Codesal
Hospital universitario de Salamanca. Salamanca
Monday, 30 December 2019
DIAGNOSIS OF CYSTINURIA BY DIRECT VISION IN THE URINARY SEDIMENT
Figure 1. Images taken in ordinary light (oc x10, obj x40) in which cystine crystals are observed at different degrees of maclation, more intense in the below image.
Cystinuria is a hyperaminoaciduria due to a defective transport of cystine and dibasic aminoacids (ornithine, arginine and lysine) in the apical membrane of the intestinal epithelium and the renal proximal tubule, which leads to an excess removal of cystine through urine. It is transmitted with an autosomal recessive inheritance pattern, with an average prevalence in neonates of 1/7000.