Correlative anaylsis between clinical patterns of urolithiasis and laboratory parameters and evaluation of risk factors in calculous kidney damage

Urolithiasis is the third most common urological disease affecting the urinary tract. However, the risk factors that may influnce the calculous kidney damage is still unclear and needs further evaluation. We retrospectively reviewed the records of 661 patients who presented to our hospital and underwent surgery for urolithiasis. All laboratory test results were obtained operatively, within a week before primary surgery. For plasma samples, we evaluated the levels of creatinine, urea, uric acid, albumin, sodium, potassium, magnesium, phosphorus, alkaline phosphate and carbon dioxide. The correlations were made with Spearman’s test. Analysis of variance (ANOVA) was applied for comparisons between more than two categories. Data were tested for homogeneity of variances (Levene’s test). When variances were found to be not homogeneous, Welch’s ANOVA was used in place of the usual ANOVA model. Male and the aged are associated with bladder calculi. Kidney calculi diseases are associated with stone recurrence, urinary infection and higher urine protein, whereas ureteral calculi are associated with higher serum calcium level. The combination of kidney and ureteral calculi are associated with higher serum creatinine. The correlation analyses of stone multiplicity with other clinical parameters revealed that stone multiplicity was positively correlated with upper tract stone sides (r=0.430, P<0.0001), large stone volume (r=0.172, P<0.0001), stone recurrence, urinary infection and urine protein. Upper tract stone sides number was positively correlated with upper tract obstruction sides (r=0.542, P<0.0001), large stone volume (r=-0.331, P<0.0001). Upper tract stone obstruction sides number was positively correlated with large stone volume (r=-0.548, P<0.0001). Our results demonstrated that upper urinary tract obstruction are more likely to correlate with abnormal electrolyte metabolism in terms of serum calcium, magnesium and phosphate. Older ages and UTI were positively associated with larger stone volume and complex stone patterns.