18 STUDIES CONCERNING THE INCIDENCE OF ESBL PRODUCING BACTERIA IN URINARY TRACT INFECTIONS Ionica Deliu*, Alina Florina Dună**, Andreea Vasilica Şovărel* *University of Pitesti, Targu din Vale Street, No. 1, Pitesti, Romania **MEDAS Medical Centre, Egalitatii Street, No. 36, Pitesti, Romania E-mail: ionica.deliu@upit.ro Abstract The emergence of antimicrobial resistant strains of pathogenic bacteria has become a great threat to the public health. One of the main risk factor for spreading of resistant bacteria is selective pressure by intense and inadequate antibiotic human therapy and increase the antibiotic resistance phenomenon in bacterial strains from natural sources. Certain bacteria have multidrug resistance to antibiotics by extended spectrum beta lactamases (ESBLs) synthesis, under plasmidial genes or transposable elements control. Resistance to fluoroquinolones and extended spectrum beta lactamases synthesis in E. coli strains limit the therapeutic options for patients with such infections. In this study 1625 urine samples from patients with suspicion of urinary tract infections were collected in the laboratory of MEDAS Medical Centre, from children and adult patients and processed by qualitative and quantitative urine cultures. The E. coli strains isolated from urine samples were tested for presence of ESBLs, 24% from E. coli strains were ESBL producers and justify the interest for this resistance mechanism. Keywords: antibiotic resistance, urinary tract infection, extended spectrum beta-lactamases. 1. INTRODUCTION Antimicrobial resistant bacteria have been a global concern and occur both in community and in hospital environment (DebMandal et al., 2011). The emergence of antimicrobial resistant strains of pathogenic bacteria has become a great threat to the public health. One of the main risk factor for spreading of resistant bacteria is selective pressure by intense and inadequate antibiotic human therapy; also, antibiotic usage as an ingredient in animal feeds or in agriculture. It was estimated that the antibiotic market worldwide consumes between 100 and 200 × 10 6 kg (Wise, 2002). Widespread use of antibiotics promotes the spread of antibiotic resistance and this is a major public health problem. This is the reason why is imperative to explore the antibiotic pressure in the environment (Wise, 2002). The urinary tract infections may be considered in hospital environment as nosocomial infection and in community as common infections. The most common pathogen for urinary tract infection, E. coli, developed multiple survival strategies to grow in nutrient deficient environment like urinary tract, for instance aerobactin, cytolysin, hemolysin synthesis. Certain Enterobacteriaceae produce nosocomial (hospital acquired) infections and have multidrug resistance to antibiotics by extended spectrum beta lactamases (ESBLs) synthesis and other mechanisms (Nica et al., 2007). This kind of antimicrobial resistance quickly spread because the responsible genes are plasmidic (and molecular characterization of plasmids is epidemiologically useful) or on the transposable elements (Khadgi et al., 2013). The best known variants of ESBL are TEM (Temoneira) and SHV (Sulphhydryl variable), recently CTX-M (Cefotaximase - Munich) (Burduniuc et al., 2012). ESBLs bacteria occur both in healthy and sick people. In healthy people ESBLs bacteria is usually not a problem (is called colonisation or carriage), but for sick people presence of these bacteria means infection with more resistant to antibiotics bacteria and makes the infection harder to treat. Beta lactamases are enzymes produced by many types of bacteria, especially in urinary tract infections, wound infections and chest infections. The major risk factors for getting an ESBLs infection are older age, prior antibiotic therapy and long term hospitalization.