Twenty-four-hour urine constituents in stone formers: a study from the northeast part of Peninsular Malaysia

Urolithiasis is a common disease with increasing incidence and prevalence world-wide, probably more common in industrialized countries. The metabolic evaluation of 24-h urine collection has been considered as part of the management of urinary stone patients. The aim of this study was to evaluate the 24-h urine constituents in stone formers and its relation to demographic data in the northeast part of Peninsular Malaysia. One hundred and six patients were recruited in this study from two hospitals in the same geographical region; 96 patients fulfilled the inclusion criteria and an informed consent was obtained from all subjects. The 24-h urine was collected in sterile bottles with a preservative agent and calcium, oxalate, citrate, uric acid, magnesium and phosphate were tested using commercial kits on a Roche Hitachi 912 chemistry analyzer. The age (mean ± SD) of 96 patients was 56.45 ± 13.43 years and 82.3% of the patients were male while 17.7% were female. The 24-h urine abnormalities were hypercalciuria (14.5%), hyperoxaluria (61.4%), hypocitraturia (57.2%), hyperuricouria (19.7%), hypomagnesuria (59.3%) and hyperphosphaturia (12.5%). Hyperoxaluria (61.4%) was the most common abnormality detected during the analysis of 24-h urine constituents in contradiction to industrial countries, where hypercalciuria was the most common finding. The high frequencies of hypomagnesuria and hypocitraturia reflect the important role of magnesium and citrate in stone formation and their prophylactic role in the treatment of urinary stone disease in the given population.