Ambulatory Evaluation of Nephrolithiasis in Korea

Park, Jin ik; Sung, Gyung Tak; Yoon, Jin Han

Abstract

In an outpatient setting, 107 patients were evaluated using a single 24-hour specimen with StoneRisk Diagnostic Profile on a random diet before medication and treatment and updated the classification of nephrolithiasis. For specific subclassification of hypercalciuric calcium(Ca) nephrolithiasis, calcium and sodium restricted diet and sodium cellulose phosphate screening test were underwent. Abnormal urinary biochemistry was classified into one or more of 20 etiologic categories. A single diagnosis was documented in 37(34.6%) patients and the remaining 65.4% had more than one diagnosis. Hypercalciuric Ca nephrolithiasis occurred in 41 (38.3%) patients and specific subclassification of 6 variants was performed. In this study, hypercalciuric Ca nephrolithiasis occurred less frequently in comparison to the incidence of U.S.A. reported by Dr. Pak. Hyperuricosuric Ca nephrolithiasis (HUCN) and gouty diathesis(GD) accounted for 47(43.9%) and 8(7.4%) patients, respectively. Hyperoxaluric Ca nephrolithiasis was in 25(23.4%) patients and all were dietary origin following an oxalate-restricted diet. Hypocitraturic Ca nephrolithiasis was seen in 51(47.6%) patients in idiopathic variant. Hypocitraturia due to RTA and chronic diarrheal syndrome occurred in 1(0.9%) and 2(1.8%) patients. Hypomagnesiuric Ca nephrolithiasis and acquired problem of low urine volume(<1 L/d) were accounted in 3(2.8%) and 13(12.2%) patients, respectively. Infection stones or cystinuria were not detected. No metabolic abnormality was found in 12(11.2%) patients. High sodium take was detected in 60(56.1%) patients, reflecting that Koreans take high sodium containing foods. We think that StoneRisk Diagnostic Profile using a single 24-hour urine specimen is very useful in detecting stone-forming risk factors and providing specific therapeutic guidelines. Additionally, recurrence associated with high cost of medical care can be reduced through adequate diagnostic evaluation as part of the treatment regimen.