Pathogenic bacteria spectrum of infectious stones and experience of preventing stone recurrence / 中华泌尿外科杂志

ABSTRACT

Objective:To investigate the pathogenic bacteria profiles in preoperative urine bacterial cultures of patients with infected kidney stones and use antibacterial drugs to prevent recurrence.Methods:The data of 79 cases with infected kidney stones admitted to the Second Affiliated Hospital of Zhengzhou University from January 2017 to July 2021 were retrospectively analyzed, among whom 29 (36.7%) were male and 50 (63.3%) were female. The age ranged from 17-75 years, with a median age of 49.0 (40, 55) years. Fifteen cases (19.0%) combined hypertension, 13 cases (16.5%) combined diabetes mellitus, and 3 cases (3.8%) combined with cardiovascular disease. Fifty-one cases (64.6%) were diagnosed with cast infectious stones. All patients underwent surgical lithotripsy, and postoperative review of the urological computerized tomography (CT) revealed no residual stones defined as complete lithotripsy, and postoperative oral medication was continued to control infection and prevent stone recurrence. According to post-hospitalization compliance, patients were divided into high and low compliance groups. The high compliance group consisted of patients who returned to the hospital regularly for routine urinalysis and urine bacterial culture after discharge, followed the doctor's prescription for standardized antibacterial drug therapy, and complied with urease inhibitor therapy for ≥6 months. The low compliance group included patients who did not take sensitive antimicrobial drugs regularly and/or were unable to adhere to the medication even after the reduction of vinblastine due to adverse events such as tremor, palpitations, headache, anemia, or gastrointestinal discomfort. The recurrence of stones at 3, 6 and 12 months of follow-up was compared between the two groups.Results:Of the 79 cases in this group, 56(70.9%) were completely clear of stone after surgery. Thirty-three cases (41.8%) presented positive in preoperative urine bacterial culture, and the most common causative organism was Aspergillus oddus in 17 cases (21.5%), followed by Escherichia coli in 8 cases (10.1%) and Klebsiella pneumoniae in 3 cases (3.8%). Among the 17 positive cases of A. oddis, six were positive for ultra broad spectrum β-lactamases (ESBLs), 6/6 were resistant to ampicillin, cefazolin, and cotrimoxazole, 1/6 were resistant to amikacin, cefoxitin, and ticarcillin/stick acid, and none were resistant to imipenem, polymyxin, or aminotrans (0/6 cases). Of the cases, 11 were negative for ESBLs. Ten out of eleven cases were resistant to ampicillin. Furthermore, 8/11 cases were resistant to cefazolin, levofloxacin, ciprofloxacin, and cotrimoxazole and 1/11 were resistant to cefoxitin, cefaclor, furantoin, amikacin, and minocycline, and 0/11 were resistant to imipenem, ticarcillin/stick acid, aminotrans. ESBLs positive strains were resistant to 78.6% of the tested drugs (cefaclor, cefazolin, ceftazidime, furantoin, norfloxacin, levofloxacin, ciprofloxacin, cefoxitin, amoxicillin/rod acid, ticarcillin/rod acid, ampicillin, ceftriaxone, cefotaxime, cefuroxime, cefepime, gentamicin, cotrimoxazole, tobramycin, amikacin, tetracycline, chloramphenicol, and minocycline) at a lower rate of resistance than ESBLs positive strains. Of the eight positive cases of E. coli, seven were ESBLs positive, 7/7 were resistant to ampicillin, cefazolin, cefotaxime, cefuroxime, and cefepime, 1/7 were resistant to cefoxitin and minocycline, and 0/7 were resistant to imipenem, furantoin, or amikacin. One case was ESBLs negative and was resistant to all antimicrobial drugs except for ampicillin. Stone recurrence rates at 3, 6, and 12 months after discharge were 9.1%(4/44) and 31.4%(11/35), 13.6%(6/44), respectively, in the high compliance group, and 60.0%(21/35), 36.4%(16/44), and 71.4% (25/35), respectively, in the low compliance group. All differences were statistically significant.Conclusion:The most common pathogenic bacteria isolated from urine bacterial cultures of patients with infectious stones were A. chimaera, E. coli, and K. pneumoniae. The resistance rate of ESBLs-positive strains to antimicrobial drugs was significantly higher than that of ESBL-negative strains, and the resistance rate of antimicrobial drugs such as β-lactamase inhibitors, cefoxitin, amikacin, and imipenem was low. Combination therapy with standardized sensitive antimicrobial drugs and urease inhibitors significantly reduced the recurrence rate of stones among patients.