Metabolic Stone Risk Factors Associated with Papillary Calcification on Unenhanced Spiral Computed Tomography / 대한비뇨기과학회지

ABSTRACT

PURPOSE: Increasing evidence suggests that Randalls plaque contributes to the pathogenesis of urinary stone formation. The purpose of our study is to compare the incidence of the abnormal metabolic stone risk factors between the calcium stone former with papillary calcification and the calcium stone former without papillary calcification on unenhanced spiral computed tomography (CT). MATERIALS AND METHODS: A series of patients with calcium stones (n=49) underwent unenhanced spiral CT and complete metabolic evaluation after they consumed a random diet for 1 month after stone removal. Of the 49 patients, 38 patients showed papillary calcification on unenhanced spiral CT and 11 patients did not. Their blood was evaluated by using a multichannel analysis sequential multichannel autoanalyzer (SMA)-20 and PTH tests. The 24-hour urinary constituents were assayed for calcium, oxalate, citrate, total volume, phosphorus and sodium. We compared the incidence of abnormal metabolic risk factors between the two groups. Statistical analysis was performed by chi-square tests. RESULTS: The incidences of hyperuricemia were 27.3% in the patients without papillary calcification and 31.6% in the patients with papillary calcification. The incidences of hypernatriuria were 18.2% versus 42.1%, the incidences of hypercalciuria were 36.4% versus 26.3%, the incidences of hyperuricosuria were 18.2% versus 18.4%, the incidences of hyperoxaluria were zero versus 28.9%, and the incidences of hypocitraturia were 45.5% versus 44.7%, respectively. The difference between the two groups was statistically significant only for hyperoxaluria (p=0.043). CONCLUSIONS: Hyperoxaluria is the only metabolic risk factor that more frequently occurred in the patients with papillary calcification. Our date suggest that hyperoxaluria may be an important factor in the pathogenesis of papillary calcification.