Microbiology of Catheter Associated Urinary Tract Infection

Urinary tract infection (UTI) is common ailment worldwide with female predominance. Catheter associated urinary tract infection (CAUTI) is the most common healthcare related infection commonly used in urinary obstruction and incontinence in critically ill patients with prolonged indwelling catheterization means more than 30 days, which is almost invariable in all patients within 14 days of catheterization which increases mor- bidity and mortality and treatment expenses. Approximately 80% of nosocomial UTI is CAUTI. CAUTI may be asymptomatic and symptomatic. 2–4% cases may develop bacter- aemia. Organisms responsible for CAUTI is similar to UTI as Escherichia coli the commonest than proteus, Pseudomonas, Klebsiella, Enterobacter, Enterococci, Candida, Serratia and rarely with Delftia tsuruhatensis , Achromobacter xylosoxidans and few others. CAUTI can be multibacterial. In CAUTI infective organisms form biofilm and propagate from there. E. coli is the most common isolate of CAUTI but Enterobacter cloacae exhibit highest biofilm production. CAUTI organisms are more antibiotic resistance than UTI. Even due to extensive use of antibiotics now Extended Spectrum Beta Lactamase (ESBL) producing CAUTI organisms are isolated from catheter biofilm. enterococci or yeasts appears to be lower than that for gram-negative bacilli. Dipstick testing for nitrites and leukocyte esterase was also shown to be unhelpful in establishing a diagnosis in catheterized patients hospitalized in the ICU [ 17 ].