LAUSR

INTRODUCTION Urinary tract infection (UTI) should be treated before percutaneous nephrolithotomy (PCNL). However, the most appropriate treatment strategy in patients with negative urine culture but positive urine dipstick infection test (positive urinary leukocyte or nitrite reaction) remains unclear. METHODS From August 2016 to February 2018, 806 consecutive patients who had undergone the first-stage PCNL with negative urine culture were included. Preoperative urinalysis, antibiotic treatment, intraoperative stone culture, and postoperative systemic inflammatory response syndrome (SIRS) were prospectively recorded. The primary outcome was SIRS. The impact of preoperative antibiotics on preoperative urinary tract infection, stone culture, and postoperative SIRS was studied. RESULTS Among the 806 participants, the rate of positive urine dipstick infection test and SIRS were 26.8% and 7.2%, respectively. In univariable analysis, positive urinary nitrite (p<0.001), positive urinary leukocytes (p<0.001), positive urine dipstick infection test (p<0.001), longer duration of pre-PCNL antibiotics (p=0.001), higher level of pre-PCNL antibiotics (p=0.010), infection stones (p=0.001), and positive stone culture (p<0. 001) were risk factors for SIRS. However, multivariable analysis showed that positive stone culture (p=0.004) and prolonged preoperative treatment with antibiotics (p=0.021) were independent risk factors for SIRS. Although preoperative antibiotics reduced the incidence of positive urine leukocyte (p<0.001) or nitrite reactions (p<0.001), prolonged or upgraded preoperative antibiotics did not affect the incidence of positive stone culture. Whether stone culture was positive (p=0.023) or negative (p=0.025), prolonged preoperative treatment with antibiotics was associated with a higher incidence of SIRS. CONCLUSIONS Enhanced preoperative antibiotic treatment based on positive urine dipstick infection tests was insufficient to reduce the incidence of positive stone culture but increased the risk of SIRS after PCNL in patients with negative urine cultures.