Exclusion criteria were current treatment for urolithiasis or hydronephrosis, pregnancy, hemo- or peritoneal dialysis, a history of kidney transplantation selleck chem EPZ-5676 or known presence of polycystic kidney disease.Procedures and definitionsClinical data and laboratory values were collected by qualified research nurses or the clinical investigators (CvN, TNB). Baseline data were collected within 24 hours of enrolment by a standardized questionnaire of the patient and reviewing the medical record. All patients were empirically treated with antibiotics according to local policy (oral ciprofloxacin 500 mg twice daily for outpatients and cefuroxim �� gentamicin intravenously for inpatients). Based on the culture results, hospitalized patients were subsequently switched to oral antibiotic treatment (first choice ciprofloxacin).

Blood cultures were obtained before commencement of antimicrobial therapy and were analyzed using local standard microbiological methods. At least two sets of 10 mL blood samples were taken and inoculated into aerobic bottles, which were incubated into an automated continuous monitoring system. In the Leiden University Medical Center (LUMC), the BACTEC 9240 (Becton Dickinson Diagnostic Instrument Systems, Sparks, MD, USA) was used, which monitors CO2 production every 10 minutes by means of a fluorescent signal. The bottles were loaded in the automated system once received at the laboratory. The time to positivity (TTP), defined as the time from the start of incubation to the start of the alert signal (as documented by the monitoring system), was recorded for each bottle of positive blood cultures.

When multiple cultures were positive, the shortest TTP was selected for analysis. TTP was analyzed for E. coli positive blood cultures and confined to results in one center, the LUMC, as the TTP depends on the microorganism and the logistics of blood culture performance (for example, transport time from blood culture obtainment to incubator) [19].Clean midstream-catch urine cultures were obtained before starting antimicrobial therapy and were analyzed using local standard microbiological methods. In case of a urinary catheter, the urine sample was collected from the port of the catheter. A positive urine culture was defined as bacterial growth over 103 CFU/ml urine or a bacterial monoculture over 102 CFU/ml urine in the presence of pyuria [20]. Urine cultures revealing growth of two or more different bacterial species reflecting mixed skin or gut flora were considered to Carfilzomib indicate contamination [20].Plasma EDTA blood samples were collected, centrifuged and stored at -80��C within two hours of patient enrolment.