Urinary Tract Infections

Urinary tract infections refer to the presence of pathogenic microorganisms within the urinary tract and its classification is usually done on the basis of infection sites:-bladder [cystitis], kidney [pyelonephritis], or urine [bacteriuria] and also can be asymptomatic or symptomatic (Quigley R 2009, Schlager TA2001). They are among the most commonly acquired bacterial infections and they account for an estimated 25-40% of the nosocomial infections (Bagshaw SM, Laupland KB 2006). Urinary tract infection (UTI) is among the most commonly occurring infection. Worldwide, about 150 million people are diagnosed with UTI annually in both developed and developing countries (Stamm WE and Norrby SR 2001). Every year as many as 7 million
Uncomplicated UTIs occur widely in sexually active healthy female patients with structurally and functionally normal urinary tracts. Complicated UTIs are those that are associated with conditions that require the need for treatment or have high the chances for therapeutic failure. These complications include abnormalities of the urinary tract that impede urine flow, the existence of a foreign body (e.g., indwelling catheter, stone), or infection with multidrug resistant microorganisms. Pyelonephritis can be considered uncomplicated when it occurs in a healthy patient (Hooton TM 2000, Stapleton AE
coli utilize a number of virulence factors to adhere the uroepithelial cells (Vranes J et al., 2001 and Johnson JR 1991). The longer the urinary catheter remains in place, the greater is the tendency of these organisms to develop biofilms, which may result in urinary tract infections. Biofilms are the microbial communities of the surface-attached cells which are embedded in a self-produced extracellular polymeric matrix (Donlan RM, Costerton JW 2002).They can cause serious problems in many areas, both in the medical (e.g. persistent and reoccurrence of infections, device-related infections) and in the non-medical (industrial) settings (e.g. bio fouling in the drinking water distribution systems and in the food processing environments). The biofilms forming microorganism have a major medical significance as they decrease the susceptibility to the antimicrobial agents. Furthermore, the cell with biofilm forming ability can facilitate a plasmid exchange and hence enhance the spread of antimicrobial resistance. (Watnick P, Kotler R