Masato Takemoto

Clinical Manifestations of Calcium Oxalate Monohydrate and Dihydrate Urolithiasis

We studied retrospectively 155 patients with calcium oxalate urolithiasis. The patients were divided into 3 groups: 1) those with calcium oxalate monohydrate, 2) those with calcium oxalate dihydrate and 3) those with mixed calcium oxalate monohydrate and dihydrate. Various differences were noted between patients with calcium oxalate monohydrate and those with calcium oxalate dihydrate, with respect to stone characteristics, spontaneous passage of stones, stone recurrence and multiple occurrence. Most important, we noted that patients with calcium oxalate dihydrate had more stone recurrences than patients with calcium oxalate monohydrate.

A New Screening Method for Cystinuria

The new kit (Urocystin) presented here utilizes the dark brown coloration which a neutral aqueous solution of cystine develops rapidly upon addition of nickel ion and sodium hydrosulfite (Na2S2O4). What is needed is pouring 4 ml of the urine sample into the kit, and the kit is able to judge without fail any urine sample with a cystine concentration of 50 µg/ml or more as positive. No pretreatment of the sample is necessary. The kit contains no hazardous reagents at all. The kit has thus turned screening of cystinuria into an extremely simple affair.