AUA 2018: Catheter Associated UTIs

San Francisco, CA (UroToday.com)  Catheter-associated UTIs (CAUTI) are the most common type of healthcare-associated infections (HAI), accounting for >560,000 nosocomial UTIS annually and approximately 75% of hospital-acquired urinary tract infections. CAUTI is associated with the prolonged use of urinary catheters, and in 2001, it occurred in 9.4 cases per 100 catheterizations. CAUTI is responsible for more than 13,000 deaths per year, largely secondary to blood stream infections, and is associated with $500 million in healthcare costs. 

Many CAUTI are considered preventable, and increasing efforts have been made to reduce their occurrence. Furthermore, growing attention surrounding CAUTI has occurred following a decision in 2008 by the Centers for Medicare & Medicaid Services (CMS) to limit reimbursements for HAI and CAUTI. CAUTI is therefore of great importance and interest, with significant morbidity, mortality, and health care costs.

In the “Plenary: Next Frontier” session moderated by Brian Schwartz, MD an Infectious Disease specialist from the University of California, San Francisco, Timothy Averch, MD, Tomas Griebling, MD, and Ben Chew, MD presented data regarding various aspects of CAUTI. 

Timothy Averch, professor of urology at University of Pittsburgh Medical Center, gave an overview of the epidemiology of CAUTI, as well as the various definitions of CAUTI and basic universal attempts to reduce its incidence. He reported that many large organizations (including the Centers for Disease Control and Infection Disease Society of America) have their own versions as to what constitutes a CAUTI. For example, although all agencies emphasized that diagnosis of a CAUTI should be based on both UTI symptoms and a positive urine test, there were variations in the degree and number of UTI symptoms required to make the diagnosis, as well as the type and values used during laboratory urine testing. Consequently, he stated it was important to know which definition was being utilized by any specific healthcare system prior to implementing risk reduction strategies. He suggested that further multidisciplinary efforts be made to avoid and reduce unnecessary tests or treatments and to set guidelines regarding indications for catheterization.

The geriatric population is particularly at risk of CAUTI due to the immunologic changes associated with aging and the high prevalence of urinary incontinence in older patients. Tomas Griebling of the University of Kansas highlighted the challenges associated with CAUTI in older populations. He reported that there are greater than 1.4 million nursing home residents, of which 13.9% of short-term residents and 7.3% of long-term residents have indwelling catheters. Multiple immunological system changes occur with aging, including altered levels of urinary cytokines, increased free radical formation and oxidative stress, decreases in cellular immunity, changes in humoral immunity, and alterations in natural host-defense mechanisms. Furthermore, older adults have chronic conditions that increase the risk of infection, including diabetes mellitus, neurological diseases, cognitive impairment, nutritional and hydration issues, and voiding and defecation dysfunction. In the case of urinary retention, chronic indwelling catheters may be useful when intermittent catheterization is not feasible; morbid obesity, lower extremity contractures, urethral strictures, cognitive limitation (e.g., dementia), and caregiver limitations, amongst others, may increase the value of using indwelling catheters. 

Griebling stated that CAUTI in the geriatric population may be more difficult to diagnose due to the atypical symptoms with which patients may present. Delirium, confusion, anorexia, new-onset urinary symptoms (urinary incontinence, urgency, frequency, and nocturia) may indicate a UTI, outside of the more common symptoms such as dysuria, pelvic pain, fevers, chills, and hematuria. To add to the complexity regarding an evaluation of UTIs in the elderly, asymptomatic bacteriuria is common (occurring in 20% of postmenopausal women, and 6% of older men), and bacterial colonization of catheters increases the occurrence of positive urine cultures. He discussed the role of the McGreer Diagnostic Criteria to diagnose UTIs in this population, which would require both symptoms of a UTI (acute dysuria or genital pain or fever/leukocytosis combined with acute costovertebral angle pain, suprapubic pain, gross hematuria, new/marked increase in urinary incontinence, urgency, or frequency) and a positive urine culture. Of note, changes in odor or color would not meet criteria for a UTI. He also reported data in which different organisms may be more likely to meet diagnostic criteria, as UTIs due to Klebsiella species can be linked to changes in mental status. Finally, he stated that quality improvement research initiatives to diagnose and treat UTIs in the elderly population are ongoing, so as to improve outcomes related to CAUTI. 

The final discussion on CAUTI involved the evolving research regarding antimicrobial coatings of catheters. Dr. Ben Chew of the University of British Columbia-Vancouver presented research from his collaboration with Dr. Dirk Lange regarding bacterial adhesion, colonization and infection related to catheters. He stated that biofilms tend to develop on the surface of catheters and increase the difficulty of antibiotic penetration. As a result, he posited that the key to CAUTI reduction was the development of a catheter coating that repelled conditioning film proteins and crystals that promote bacterial adhesion. 

The plenary session provided an overview of the multiple challenges in both the evaluation of CAUTI as well as its prevention. Each presenter emphasized the need for further multidisciplinary research efforts to address this growing public health concern.

Moderator: Brian Schwartz, MD, University of California, San Francisco
Panelists: Tomas Griebling, MD, MPH, University of Kansas School of Medicine,  Timothy Averch, MD, FACS, UPMC, Jeremy Burton

Written by:  Judy Choi, MD, Assistant Professor, Department of Urology, University of California, Irvine @judymchoi at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA
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