Risk factors analysis of urinary tract infection after flexible ureteroscopy combined with holmium laser lithotripsy for kidney calculi with human immunodeficiency virus infection

Objective To investigate the risk factors of urinary tract infection after flexible ureteroscopy combined with holmium laser lithotripsy for kidney calculi with human immunodeficiency virus infection. Methods A total 96 patients from June 2016 to June 2018 were analyzed retrospectively. It included 53 males and 43 females, aged 21 to 57(average 41) years old. All patients were diagnosed with kidney stones by KUB, IVU and CT examination. 19 cases of bilateral kidney stones and 37cases in left and 40 cases in right. 67 cases of single stones and 29 cases of multiple. There were 34 cases of renal pelvis calculi, 19 cases of meddle calyx, 17 cases of superior calyx and 26 cases of inferior calyx. Maximum diameter of calculus was 0.8-2.9 cm, average(1.6±0.8)cm, of which 49 cases size were over 2 cm. There is no obvious stenosis of the renal pelvis and ureter. There were 29 cases of CD4+ lymphocyte count ≤400/μl, and 26 cases of preoperative ureteral stents. Urine test and urine bacterial culture were confirmed no urinary tract infection before lithotripsy. 46 cases with abnormal white blood cells due to urinary test could not meet the diagnostic criteria for urinary tract infection, and prophylactic antibiotics, 51 cases without antibiotics. All 96 cases underwent lithotripsy and record postoperative conditions. Then single factor analysis and multi-factor logistic regression analysis were used to analyze the related factors of urinary tract infection after lithotripsy. Results All 96 cases were successfully completed, no open surgery, no complications. The operation time was 40-130 min (average 57 min), of which 34 cases were over 60 min. Postoperative retained catheter time was 2 to 11 days (average 3.5 days), of which 27 cases were over 7 days. Urinary tract infection occurred in 18 of all patients, with an incidence of 18.8%. The results of urinary bacterial culture in 18 cases were 13 cases of Escherichia coli infection, 3 cases of Proteobacteria infection, and 2 cases of fecal cocci infection. There were 14 cases of calculi size over 2 cm, 10 cases of CD4+ lymphocyte count≤400/μl, 11 cases of preoperative ureteral stents, 3 cases of prophylactic antibiotics, 11 cases of operation time over 60 min, and 10 cases of postoperative retained catheter over 7 days. Single factor analysis found that CD4+ lymphocyte count≤400/μl, preoperative ureteral stents, larger calculi size, longer operation time, postoperative retained catheter for a long time could increase the risk of urinary tract infection after operation (P<0.05), Preoperative prophylactic antibiotics could reduce the incidence of postoperative infection (P<0.05). Multivariate logistic regression analysis suggested that CD4+ lymphocyte count ≤400/μl, preoperative ureteral stents, calculi size over 2 cm, operation time more than 60 min, postoperative retained catheter more than 7 days, and no prophylactic antibiotics before surgery were risk factors for postoperative urinary tract infection(P<0.05). Conclusions CD4+ lymphocyte count ≤400/μl, preoperative ureteral stents, calculi size over 2 cm, operation time more than 60 min, postoperative retained catheter more than 7 d, and no preventive use of antibiotics before surgery are risk factors for urinary tract infection after flexible ureteroscopy combined with holmium laser lithotripsy with human immunodeficiency virus infection. Key words: HIV infection; Kidney calculi; Flexible ureteroscopy; Urinary tract infection