Metabolic Factors Associated With Urinary Calculi in Children

Introduction. We aimed to identify metabolic and anatomicalabnormalities present in children with urinary calculi.Materials and Methods. Metabolic evaluation was done in 142pediatric calculus formers. Evaluation included serum biochemistry;measurement of daily excretion of urinary calcium, uric acid, oxalate,citrate, and magnesium (in older children); and measurement ofcalcium, uric acid, oxalate, and creatinine in random urine samplesin nontoilet-trained patients. Urinary tests for cystinuria were alsoperformed. All of the patients underwent renal ultrasonography.Results. Sixty-one patients (42.7%) had metabolic abnormalities.Anatomical abnormalities were found in 12 patients (8.4%). Threechildren (2.1%) had infectious calculi, and 3(2.1%) had a combinationof metabolic and anatomic abnormalities. In 66 children (46.2 %)we did not find any reasons for calculus formation (idiopathic).Urinalysis revealed hypercalciuria in 25 (17.6%), hyperuricosuriain 23 (16.1%), hyperoxaluria in 17 (11.9%), cystinuria in 9 (6.3%),hypocitraturia in 3 (2.1%), and low urinary magnesium level in1 (0.7%) patients. Sixteen patients (11.2%) had mixed metabolicabnormalities.Conclusions. Metabolic abnormalities are common in pediatricpatients with urinary calculi. In our study, calcium and uric acidabnormalities were the most common, and vesicoureteral refluxseemed to be the most common urological abnormality which ledto urinary stasis and calculus formation