Infections in patients with spinal cord injuries.

Abstract

Approximately 8,000 persons survive spinal cord injury urinary tract infection in patients with SCIs. Performance of intermittent catheterization and bladder-neck manipulation (SCI) each year in the United States. About 200,000 Americans have reduced the morbidity associated with neurogenic bladder. have spinal cord injuries, and this number is increasing as life Changes in the bladder associated with the long-term use of expectancy increases towards normal levels for these persons. indwelling catheters include squamous metaplasia, thickening Nosocomial infection is common in patients with SCIs because and fibrosis of the bladder, diverticula, calculi and the presence these patients are admitted to the hospital immediately after of multiple organisms, alkaline-encrusting cystitis with ureasetheir injuries occur, and they stay for a considerable time for producing bacteria, penile and scrotal fistulae, abscesses and management of the injuries and for rehabilitation. Because of epididymitis, and squamous cell carcinoma of the bladder. the prolonged stay, these patients are at greater risk of develIntermittent catheterization is associated with an increased oping infections with resistant microorganisms including methincidence of bacteriuria, which may be influenced by the freicillin-resistant Staphylococcus aureus (MRSA) and multiresisquency of catheterization. As the interval between catheterizatant gram-negative bacilli. Patients with SCIs frequently have tions increases, the incidence of bacteriuria may increase. Pawounds on the neck, chest, or abdomen and often are at additients who are unable to perform intermittent catheterization tional risk from surgery and the use of blood products. High themselves are also at greater risk of infection [2]. doses of corticosteroids, given immediately after injury, may A wide range of microorganisms has been isolated from predispose these patients to infection as well as to upper gastropatients with SCIs and urinary tract infections. The presence intestinal complications [1]. After discharge from the hospital of bacteria that are urease producers raises concerns about and rehabilitation, the incidence of infection, usually of the calculus formation. Infection due to Escherichia coli strains urinary tract, respiratory tract, and infected pressure ulcers, that may be more virulent than other strains has not been continues to be increased for patients with SCIs. well studied. The virulence of some bacterial species, such as Pseudomonas, in the urinary tracts of patients with SCIs has Urinary Tract Infections been questioned, but there are sufficient data showing that tissue invasion and bacteremia with Pseudomonas aeruginosa Bacteriuria is almost universal in patients with SCIs. This are not uncommon. infection may be asymptomatic colonization, but tissue invaE. coli and species of Pseudomonas, Klebsiella, and Enterosion of the urinary tract occurs in most patients initially during coccus have been the predominant microorganisms that cause hospitalization and rehabilitation and may be a recurrent proburinary tract infections in patients with SCIs. A high prevalence lem for most of these patients throughout their lives. At one of Proteus species, which may relate to the more frequent time, these infections were the dominant cause of bacteremia, use of indwelling catheters, has been noted at some centers. renal failure, and death among patients with SCIs until the Klebsiella, Pseudomonas, and Proteus species tend to be more methods of urinary drainage improved; however, serious comresistant than E. coli to commonly used antibiotics, but outplications, bacteremia, calculi, pyelonephritis, and renal failure breaks of infection with multiresistant gram-negative bacilli still occur. have been described relatively infrequently in SCI units. An increased volume of residual urine and increased bladder A patient’s sex and level of injury may affect the microbiolpressure have been the most important factors responsible for ogy of bacteriuria and colonization. At our institution, the incidence of infection with Klebsiella and Pseudomonas species among male patients has been high, which may be related to the use of external condom catheters. In one study of female Received 16 July 1997. patients with SCIs who underwent intermittent catheterization, Reprints or correspondence: Dr. John Z. Montgomerie, Rancho Los Amigos Medical Center, 7601 East Imperial Highway, 244 HB, Downey, California E. coli and Enterococcus species accounted for 71% of infec90242. tions [3]. Clinical Infectious Diseases 1997;25:1285–92 Because of loss of sensation, patients with SCIs do not have q 1997 by The University of Chicago. All rights reserved. 1058–4838/97/2506–0001$03.00 the common symptoms of urinary tract infection such as fre-