Frequency and antimicrobial resistance patterns of bacteria implicated in community urinary tract infections: a ten-year surveillance study (2000-2009)

BACKGROUND Urinary tract infection (UTI) is one of the most common infectious diseases at the community level. In order to assess the adequacy of the empirical therapy, the prevalence and the resistance pattern of the main bacteria responsible for UTI in the community (in Aveiro, Portugal) was evaluated throughout a ten-year period. METHODS In this retrospective study, all urine samples from patients of the District of Aveiro, in ambulatory regime, collected at the Clinical Analysis Laboratory Avelab during the period 2000-2009 were analysed. Samples with more than 105 CFU/mL bacteria were considered positive and, for these samples, the bacteria were identified and the profile of antibiotic susceptibility was characterized. RESULTS From the 155597 samples analysed, 18797 (12.1%) were positive for bacterial infection. UTI was more frequent in women (78.5%) and its incidence varied with age, affecting more the elderly patients (38.6%). Although E. coli was, as usual, the most common pathogen implicated in UTI, it were observed differences related to the other bacteria more implicated in UTI relatively to previous studies. The bacteria implicated in the UTI varied with the sex of the patient, being P. aeruginosa a more important cause of infection in men than in women. The incidence of the main bacteria changed over the study period (P. aeruginosa, Klebsiella spp and Providencia spp increased and Enterobacter spp decreased). Although E. coli was responsible for more than an half of UTI, its resistance to antibiotics was low when compared with other pathogens implicated in UTI, showing also the lowest percentage of multidrug resistant (MDR) isolates (17%). Bacteria isolated from females were less resistant than those isolated from males and this difference increased with the patient age. CONCLUSIONS The differences in sex and age must be taken into account at the moment of empirical prescription of antimicrobials. From the recommended antimicrobials by the European Association of Urology guidelines, the first line drugs (pivmecillinam and nitrofurantoin) and the alternative antibiotic amoxicillin-clavulanic acid (AMX-CLA) are appropriate to treat community-acquired UTI, but the fluoroquinolones should not be suitable to treat male infections and the trimethoprim-sulfamethoxazole (SXT) shall not be used in the treatment of UTI at this level.Thanks are due to the University of Aveiro, Centre for Environmental and Marine Studies (CESAM) for funding the Microbiology Research Group (Project Pest-C/MAR/LA0017/2011) and to Clinical Analysis Laboratory Avelab (Portugal) for supplying the data.publishe

Community-acquired urinary tract infections by extended-spectrum beta-lactamase-producing Enterobacteriaceae in Zenica-Doboj Canton, Bosnia and Herzegovina

The aim of this study was to determine the incidence and antimicrobial resistance of ESBL-producing strains in the community-acquired urinary tract infections (CAUTIs), which is necessary for antimicrobial therapy selection. From January 2003 to September 2004, 4,112 consecutive, non-duplicate coliform isolates from CAUTIs were analyzed. Antimicrobial susceptibility testing to fifteen antimicrobials was performed by disc-diffusion method. Double-disk synergy test (DDST) with amoxicillin-clavulanat, cefotaxime, ceftazidime, ceftriaxone and aztreonam, and Etest strips with PM/PML (AB Biodisk) was performed according to CLSI recommendation in order to detect the ESBL producers. The overall incidence of ESBL producing strains was 2.6% (108/4112), it was significantly higher in males, 8.4% (79/936) than in females, 0.9% (29/3176). The highest prevalence of ESBL producers was noted in the oldest and youngest age group: 4.8% (52/106) and 2.6% (27/1045), respectively. An increase from 2.2% (52/2402) to 3.3% (56/1710), and a shift of ESBL producers toward the age group 0-6 years (1.6% and 3.8%, respectively) in this period was observed. The incidence of ESBL producing strains among isolated Klebsiella spp. were 7.8% (83/1060), E. coli 0.7% (18/2561), Citrobacter spp. 0.6% (1/156), Enterobacter spp. 7.7% (3/39) and Proteus spp. 1.0% ( 3/297). Among ESBL producing isolates Klebsiella spp. predominated, 76.9% (83/108), followed by E. coli 16.7% (18/108). ESBL producing strains showed significantly higher resistance rates to all tested antibiotics as compared to to non-ESBL-producers. The increase and shift toward the youngest age group of the ESBL producer incidences is of our concern. Further studies are required to detect ESBL types in terms of highly different geographical dissemination of these isolates

Molecular characterisation of methicillin-susceptible and methicillin-resistant Staphylococcus aureus in inpatients and outpatients in Bosnia and Herzegovina

The aim of this study was to investigate the genetic background of methicillin-susceptible (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) obtained from clinical specimens of inpatients and outpatients. Methicillin resistance was confirmed by the presence of the mecA gene by PCR. The genetic characterisation was performed using spa typing and the algorithm based upon repeat pattern (BURP). Staphylococcus aureus was isolated from 68 and 79 inpatient and outpatient samples, 31 (46 %) and 14 (18 %) of which were MRSA, respectively. Among 37 inpatients and 65 outpatients with MSSA, 22 and 38 spa types were clustered into seven and eight spa-CCs, respectively. The main MSSA spa-CC of inpatients and outpatients was spa-CC015 (multilocus sequence typing (MLST) CC45). Most MRSA were associated with spa-CC355/595 (MLST CC152). MRSA-related background was found in 32 % of inpatients and 43 % of outpatients with MSSA, suggesting that MRSA did not arise from predominant MSSA clones

Antibiotic Resistance Pattern of Community Acquired Uropathogens at a Tertiary Care Hospital in Jaipur, Rajasthan

Background: Urinary tract infections (UTIs) are amongst the most common infections described in outpatients setting. Objectives : A study was conducted to evaluate the uropathogenic bacterial flora and its antimicrobial susceptibility profile among patients presenting to the out-patient clinics of a tertiary care hospital at Jaipur, Rajasthan. Materials and Methods : 2012 consecutive urine specimens from symptomatic UTI cases attending to the outpatient clinics were processed in the Microbiology lab. Bacterial isolates obtained were identified using biochemical reactions. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) production was determined by the double disk approximation test and the Clinical and Laboratory Standards Institute (formerly NCCLS) confirmatory method. Results: Pathogens were isolated from 346 (17.16%) of the 2012 patients who submitted a urine sample. Escherichia coli was the most frequently isolated community acquired uropathogen accounting for 61.84% of the total isolates. ESBL production was observed in 23.83% of E. coli strains and 8.69% of Klebsiella strains. With the exception of Nitrofurantoin, resistance to agents commonly used as empiric oral treatments for UTI was quite high. Conclusion : The study revealed E. coli as the predominant bacterial pathogen for the community acquired UTIs in Jaipur, Rajasthan. An increasing trend in the production ESBLs among UTI pathogens in the community was noted. Nitrofurantoin should be used as empirical therapy for primary, uncomplicated UTIs