Aim: To investigate the feasibility of using biological markers for determining the optimal timing to repeat lithotripsy of urinary stones.
Materials and methods: This was a prospective, randomized, single-center cohort study of 100 patients randomized into 4 groups. Patients of group I (n=46), II (n=20), III (n=18) and IV (n=16) were used contact lithotripsy (URS), ESWL, PNL, combined lithotripsy. In all patients, before surgery and at 1, 7, 14, 20 days after lithotripsy, iron-induced urine chemiluminescence was measured to determine the level of reactive oxygen species (ROS) and concentration of medium-mass molecules (MMM) in urine.
Results: Analyzing the time of operation and the size of stones only in group I was detected the significant negative correlation (r=-0,479, p<0,05). In patients of all groups, the level of ROS have decreased after the surgery with further returning to baseline level. Dynamics of changes MMM in urine has not revealed a reliable change tendency.
Conclusion: The definition of the quantity of ROS in urine is a promising criterion in measuring the degree of urinary system damage and the time for repeated lithotripsy. The level of ROS in the urine after URS, ESWL and the ESWL-URS combination returns to baseline on the 7th day and after PNL on the 14th day postoperatively, thus allowing to pathogenetically define the optimal timing of repeat lithotripsy.
Keywords: biological markers; lithotripsy; medium-mass molecules; reactive oxygen species; urolithiasis.