Microbiological follow-up of nosocomial infections in a single urological center

Background: To analyze data from the cultural examinations of different biological fluids, obtained from urologic patients from January 2007 to April 2010, in order to describe the incidence of infections in our setting. Methods: In the period of reference a urine culture was carried out for every patient admitted, in case of suspected urinary tract infection, a blood culture in case of suspected sepsis, and a wound culture in case of wound infection. Results: In the period of investigation 321 patients developed some kind of infection: 589 positive isolations obtained from cultural examinations have been diagnosed in urine (63%), blood (6%), surgical wound (6%), venous central catheter (7%) and other sites (18%) (tip of ureteral and bladder catheters). The most commonly isolated pathogenic agent for all the sites of infection has been Escherichia coli (22.5%). In urine, the most frequently isolated species have been Escherichia coli (27.8%), Enterococcus (12.5%), and Candida spp (9.3%). Escherichia coli (22.9%), Pseudomonas (5.7%), and Staphylococcus aureus (3.5%) were the most frequently found pathogenic agents responsible for sepsis, compared to others. In the period of investigation we have recorded 35 episodes of sepsis. Conclusions: Empiric antibiotic therapy is frequent in cases of clinical evidence of infection, before the identification of the causative microorganism is available; therefore, it is important to know which are the bacterial species mainly responsible for these specific infections. We need continuous surveillance of infections and the improvement in the use of antibiotic therapy in order to limit the antimicrobial resistance.