Annals of Long Term Care

Urinary tract infections (UTIs) are the most common cause of bacteremia in long-term care (LTC) patients and may present with subtle nonspecific symptoms. UTIs should be suspected in older adults in LTC who manifest a sudden problem with incontinence, decreased physical or cognitive function, or loss of appetite. When a UTI is suspected, empiric antibiotics should be started based on the local infection pattern. Typically, trimethoprim/sulfamethoxazole is the major first-line empiric agent. Antibiotic prophylaxis to prevent UTIs may be required in postmenopausal women with frequent recurrent UTIs, patients about to undergo urologic or gynecologic procedures, patients with spinal cord injury, and men with chronic bacterial prostatitis. Although the high incidence of bacteriuria exists with the use of indwelling catheters, antibiotic prophylaxis is not recommended. Because asymptomatic bacteriuria does not require treatment, there is no role for periodic urine cultures in the chronically catheterized patient. (Annals of Long-Term Care: Clinical Care and Aging 2010;
18[2]:35-39)

Introduction/Epidemiology

Lower urinary tract infections (UTIs) are a major cause of morbidity and mortality for adults in long-term care (LTC).1 Community studies have shown prevalence rates of bacteriuria to be 11% in the elderly, 18% for those living in congregate living arrangements, and 25-50% for residents in nursing home environments.2-4 In fact, the most common cause of bacteremia in LTC residents is due to UTIs.1 The prevalence of UTI increases in both sexes with age, resulting in a female-to-male ratio of 2:1 in the elderly population. The annual incidence of symptomatic bacterial UTIs is estimated to be as high as 10%. For asymptomatic bacteriuria, the estimated cumulative prevalence is 30% in women and 10% in men. Interestingly, the female-to-male ratio in the incidence of UTI narrows in the elderly population, which is thought to be related to the fact that with increasing age, men develop an increase in residual urinary volume after voiding, which increases their risk of bacteriuria and UTI; women engage in less sexual activity with age, and thus have one less predisposing risk factor for introduction of bacteria into the urinary tract.

Sign and Symptoms

UTIs are defined as infections of the urethra, bladder, ureters, and/or kidneys. Infections of the urethra and bladder are considered lower UTIs, while infections of the ureters or kidneys are considered upper UTIs. These infections can be classified according to localization as urethritis (urethra), cystitis (bladder), or pyelonephritis (kidney). In men, infections of the prostate gland (prostatitis) can mimic or complicate UTIs. They typically present with a classic triad of dysuria, urinary frequency, and suprapubic pain or discomfort. Other symptoms include recent incontinence, flank pain, fever, and/or lethargy. In the LTC patient, UTIs present with subtle nonspecific symptoms such as decreased appetite and/or oral intake, decreased physical activity, increased agitation, and/or combativeness. LTC patients might demonstrate recent onset of functional decline, anorexia, nausea, vomiting, or mental confusion. UTIs may also be classified by the presence (symptomatic) or absence (asymptomatic) of symptoms. Asymptomatic bacteriuria is defined as 105 colony-forming units (CFUs)/mL or more without symptoms or other signs of infection. Only about 70% of asymptomatic patients with high colony counts in a single urine sample have true bacteriuria as confirmed on a second sample.

While defined by a single occurrence of infection, UTIs may be identified as sporadic, relapsing, or a re-infection. Sporadic infections are defined as 3 or more (or 2 or more, according to some investigators) episodes of asymptomatic bacteriuria within 1 year.