role of urinary oxalate excretion in renal calculogenesis

ABSTRACT

The present study was undertaken with the aim to determine the role urinary oxalate excretion in renal lithiasis. The study was conducted on 60 renal calculus patients admitted in various Government Hospital of Lahore during the period from April to August 1996. Thirty normal subjects, with matched age and sex, were also included in this study, as a control group. Majority of the patients, 58 [97.7%], belonged to low and middle socio-economic classes. The mean daily excretion of oxalate in patients was significantly higher [P< 0.01] as compared to control group with a mean of 35.9 +/- 2.54 mg. moderate hyperoxaluria [24 hours oxalate excretion > 45 mg/day] was seen in significantly higher number of patients [25 out of 60], as compared to controls [5 out of 30]. The daily urinary oxalate was high in patients had pure calcium oxalate calcui and mixed calcium oxalate and uric acid calcui [with calcium oxalate as main component] as compared to patients with other renal calculi components. The ionic product of calcium oxalate was significantly higher [P< 0.01] in patients than controls. In the study the mean calcium excretion was 21.6% higher in the patients than the controls subjects, whereas oxalate excretion was 25% higher, which is statistically significant. These results suggest that increased oxalate excretion may be as important as increased calcium excretion in the aetiology of calcium oxalate calculus. The measurement of urinary oxalate and calcium is clearly useful in the management of calcium oxalate calculus formers