Hospital-acquired Urinary-Tract Infections

Abstract

Virtually all patients in whom indwelling urethral catheters are inserted will develop bacteriuria and infection within the urinary tract. The organisms associated with hospital-acquired urinary tract infections include Escherichia coli, Klebsiella-Aerobacter species, Proteus species and Pseudomonas aeruginosa, as well as other less common organisms. Specific serotypes of each of these organisms would appear to have an increased propensity for producing urinary-tract infections. The major source of organisms is the fecal bacterial flora except for strains of Pseudomonas aeruginosa, which are of exogenous origin. Study of the epidemiology suggests that most hospital-acquired urinary infections are spread by means of personnel or fomites to other patients and their drainage equipment, although autoinfection by fecal organisms has been demonstrated. Urinary-tract contamination is then the consequence of movement of bacteria either via the lumina of catheters or along the mucous sheath between the catheter and urethra. Control of these infections can be accomplished either by meticulous attention to the prevention of bacteria from entering the bladder or through the application of techniques to remove bacteria from the bladder and to prevent their multiplication within the bladder.