Aim. To identify informative clinical and prognostic risk factors for urinary tract inflammatory exacerbation in patients with urolithiasis (UL) after laser lithotripsy.

Materials and methods. The study included 74 patients with UL who underwent laser lithotripsy using the holmium laser MultiPulse HoPlus (Germany) in fragmentation mode with a pulse energy of 1.2 J, a frequency of 20 Hz. Patients were divided into groups according to the presence of laboratory signs of urinary tract inflammation on the second postoperative day. Urinalysis for all patients was performed using an automated urine analyser, Laura Xl Erba (Germany). The obtained data were statistically processed with Statistica 13 for Windows (StatSoft Inc., No. JPZ804I382130ARCN10-J).

Results. On the second day after laser lithotripsy, 48.6 % of patients with UL presented with laboratory signs of urinary tract inflammatory exacerbation, characterized by leukocyturia (100 %), elevated epithelial cell count (72.2 %), erythrocyturia (100 %), bacteriuria (88.9 %), and crystalluria (83.3 %). The signs of urinary tract inflammatory exacerbation were correlated with acute inflammatory indicators. Inflammatory changes on the second postoperative day were significantly more frequent in patients with comorbid diabetes mellitus (р = 0.03), chronic pyelonephritis in remission at the time of lithotripsy (р = 0.04) and their combination (р = 0.04). The duration of laser lithotripsy of ≥60 minutes was associated with a higher frequency of urinary tract inflammation (р = 0.01 in patients with UL on the second day after lithotripsy. The most informative independent prognostic risk factors for urinary tract inflammatory exacerbation in patients with UL on the second postoperative day were comorbid chronic pyelonephritis (p = 0.040) and lithotripsy duration ≥60 minutes (p = 0.016).

Conclusions. Comorbid chronic pyelonephritis and lithotripsy duration ≥60 minutes are significant prognostic risk factors for urinary tract inflammatory exacerbation in patients with UL on the second day after laser lithotripsy.