Physico-biochemical parameters of urine and blood and biominerology of urinary bladder stones in patients with bladder outlet obstruction

Abstract

BACKGROUND: Bladder outlet obstruction is one of the main factors leading to the formation of stones in the urinary bladder. Understanding of the physico-biochemical processes in urine and blood, as well as the biomineralogy of urinary bladder stones, will make it possible to determine the pathogenetically justified treatment of such patients. AIM: The aim of the study was to identify and study the relationship between the physico-biochemical parameters of urine and blood and the biomineralogical composition of urinary bladder stones in patients with bladder outlet obstruction. MATERIALS AND METHODS: A comprehensive examination of 76 patients at the age of 37 to 89 years with urinary bladder stones occurred against the background of bladder outlet obstruction was carried out. A comprehensive diagnosis, including an assessment of the physico-biochemical parameters of urine and blood, bacteriological urine tests, radiological diagnostics, as well as biomineralogical studies of concretions, was carried out. RESULTS: The data obtained show that not all physicochemical parameters of blood and urine of the subjects are comparable with the data of patients with nephrolithiasis. In the vast majority of the studied kidney calculi were not detected, in addition, blood biochemical parameters, including the level of stone-forming substances were within the reference values. In urine tests an increase in some lithogenic substances is detected. Urinary stones in patients with bladder outlet obstruction had a mixed composition, more often phosphates and uric acid salts were detected (75 and 54% of cases, respectively). Considering the nature of metabolism and the increase in uric acid excretion with age, as well as the presence of residual urine in case of bladder outlet obstruction, it can be assumed that uric acid is the primary matrix in cystolithiasis. The data obtained indicate a connection between the infectious process in the bladder and the composition of urinary stones. Against this background, there is a more intensive process of cystolithogenesis. CONCLUSIONS: The algorithm for the diagnosis of urinary bladder stones secondary to bladder outlet obstruction should include not only the collection of anamnesis and the performance of routine blood and urine tests, but also specific physical and biochemical studies, as well as assess the biomineralogy of urinary stones, which will make it possible to choose an adequate tactics for the pathogenetic treatment of patients and effective metaphylaxis of stone formation.