Моніторинг клініко-біохімічних особливостей перебігу сечокам’яної хвороби на тлі постковідного синдрому

The objective: to investigate the clinical and biochemical features of the course of urolithiasis (UL) against the background of post-covid syndrome (PCS) by determining the activity levels of the tubular nephrothelium enzymes N-acetyl-β-Dglucosaminidase (NAG) and β-galactosidase (β-Gal) as enzymological markers of the functional state of the kidney parenchyma and concentrations of oxalic and uric acids, as well as calcium as the main risk factors for the formation of calculi in the kidneys before stone removal and 6 ± 1 months after their removal. Materials and methods. 118 patients with UL were examined, of which 66 patients made up the study group (SG), these are patients with UL and PCS, 52 patients made up the comparison group (CG), these are patients with UL who did not suffer from COVID-19. Control group – 32 practically healthy people. Urine enzyme activity and concentrations of oxalic acid, calcium, and uric acid as promoters of stone formation were performed before stone removal and 6 ± 1 months after their removal against the background of metaphylactic measures. The activity of NAG and β-Gal was expressed in μmoles of para-nitrophenol formed in 1 hour of incubation based on 1 mmol of urinary creatinine (μmol/h/mmol of creatinine). Concentrations of uric acid and calcium in blood serum and urine were expressed in mmol/l, concentration of oxalic acid in urine was expressed in mg/l. Excretion of oxalic acid in daily urine (mg/day) was also determined. The composition of the stone that was removed was determined by infrared spectroscopy on a Spicord-CV device. The results. It was established: the course of UL in patients with PCS (SG) was accompanied by an increase in the frequency of all concomitant diseases; patients from both groups have a decrease in diuresis during the pre-treatment period; the activity levels of lysosome enzymes in patients from SG statistically significantly exceeded similar indicators CG, which indicates more significant hypoxic-ischemic shifts in the kidney parenchyma and a more pronounced violation of the functional state of the tubular nephrothelium in these patients than in the CG; in patients with UL from SG the levels of concentrations of oxalic and uric acids in urine exceeded, although not significantly, which indicates more pronounced conditions in these patients regarding the recurrent development of stones than in the CG, an increase in the risk of stone formation in the SG of patients compared to CG is also evidenced by a probable increase in the blood serum concentration of uric acid – one of the main promoters of kidney stone formation in each of the types of urolithiasis. It is shown that in both groups of patients oxalic acid stones predominate, but in the group of patients with PCS, the proportion of uric acid stones increases. The results of the examination of patients from SG and CG after the removal of the calculus and metaphylactic treatment after 6 ± 1 months showed a certain tendency towards the normalization of all the investigated indicators, but in patients from SG, changes in all indicators are carried out much more slowly than in patients from CG, that is, in patients with PCS, the effectiveness of long-term treatment is reduced, which requires the development of more effective schemes of metaphylactic treatment to prolong the relapse-free period. Conclusions. The obtained results demonstrate the negative effect of PCS on the UL course, which is probably caused by prolonged immunological changes, which, supporting endothelial dysfunctions, contribute to complex multifaceted pathophysiological and pathobiochemical processes, which indicates the need for further monitoring and strengthening of metaphylactic and general treatment measures.