A European perspective on nosocomial urinary tract infections I. Report onthe microbiology workload, etiology and antimicrobial susceptibility (ESGNI-003 study)

Objectives To obtain information on the microbiology workload, etiology and antimicrobial susceptibility of urinary tract infection (UTI) pathogens is olated in European hospitals. Materials and methods We collected data available in the microbiology units of a large sample of European hospitals regarding the laboratory workload, diagnostic criteria, and etiology and antimicrobial resistance of the urin ary isolates collected on one day (the: study day). Results Data were received from a total of 228 hospitals from 29 European c ountries. The average rate of urine samples cultured per 1000 admissions in 1999 was 324. The criteria to consider a positive urine culture as signifi cant were quite variable; greater than or equal to 10(4) colony-forming uni ts (CFU)/mL for bacteria or greater than or equal to 10(3) CFU/mL in the ca se of yeasts were the most used cut-off points. On the study day, a total o f 607 micro-organisms from 522 patients with nosocomial UTI were isolated. The six most commonly isolated micro-organisms were, in decreasing order; E scherichia coil (35.6%), Enterococci (15.8%), Candida (9.4%), Klebsiella (8 .3%), Proteus (7.9%) and Pseudomonas aeruginosa (6.9%). Pseudomonas was iso lated more frequently in non-EU countries. The study data reveal high rates of antimicrobial resistance in UTI pathogens, especially in non-EU countri es, where Pseudomonas aeruginosa presented rates of aminoglycoside resistan ce as high as 72% to gentamicin, 69.2% to tobramycin and 40% to amikacin. Conclusions Nosocomial UTI accounts for an important proportion of the work load in microbiology laboratories. A consensus on the practice and interpre tation of urine cultures in Europe is needed. The levels and patterns of re sistance of UTI pathogens must be a serious cause for concern and a clear r eason for stricter guidelines and regulations in antimicrobial policy.