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COPYRIGHT 2004 Jannetti Publications, Inc.
Urinary tract infections (UTIs) are common in the elderly, yet there is much disagreement in the literature regarding many aspects of this condition. To assist the nurse in developing optimum care strategies, UTI criteria in the elderly are discussed. Using the most recent knowledge to guide clinical assessment and intervention skills, the long-term care facility nurse and nurses who care for the elderly can influence positive outcomes in this challenging population.
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Urinary tract infections (UTIs) are the most common type of nosocomial infection found in long-term care facilities (LTCFs) (Warren, Palumbo, Fitterman, & Speedie, 1991). Yet, there is much to be understood about UTIs in the elderly (generally considered to be those over 64 years old). Just as children are medically not small adults, the elderly are not necessarily older adults. They are unique in many ways. Urinary tract infection requiring antibiotic treatment is defined in the general population as the presence of significant amounts of a single microorganism in the urine (Winsinger, 1996). In the elderly, researchers have found that significant bacteriuria, even with accompanying pyuria, is not sufficient as an indicator for a UTI or antibiotic therapy (Nicolle, 2000). Further, symptoms of a UTI in the general population are not always applicable to the elderly. However, at present, there is no consensus on the definition and management of an elderly UTI. To give optimal care, the LTCF nurse, who plays a key role in initiating assessment and determining treatment, should be aware of both the uniqueness of UTIs and the contentious nature of their diagnosis in this population (Beier, 1999; Nicolle, 2000; Smith, 1998). The three criteria that, at present, are considered diagnostic for a UTI in the institutionalized elderly are: bacteriuria, pyuria, and symptoms (Garner, Jarvis, Emori, Horanm, & Hughes, 1988; Jackson et al., 1992; Loeb et al., 2001; McGeer et al., 1991). See Table 1 for a composite of the proposed criteria for a UTI. It should be noted that these authors do not share consensus regarding diagnostic criteria. Other possible symptoms as well as nursing implications for managing UTI in the elderly population will also be discussed.
CRITERIA FOR URINARY TRACT INFECTIONS
Bacteriuria
Colony counts. The hallmark of a UTI has been the presence of a single microorganism of [greater than or equal to] [10.sup.5] colony forming units (cfus) per ml in a clean-catch or midstream urine specimen, with lower numbers usually indicating contamination (Kass, 1957). Studies of the general population have suggested lower colony counts for reasons which include: an early stage of infection, recent use of antibiotics, cleaning the perineum with an antiseptic, frequency of urination, urinary tract obstruction, state of hydration (including the time of day the specimen was collected), urine pH or specific gravity, or antibiotic therapy (Kass, 1957; Kunin, White, & Hua Hua, 1993; Pollack, 1983; Strand, Bryant, & Sutton, 1985).
In studies of UTIs in the elderly, there is a lack of agreement with research findings. One study recommended increasing the significant level of bacteriuria to [10.sup.6] cfu/ml due to the spontaneous recovery of elderly individuals with [10.sup.5] cfu/ml and the increased likelihood of contamination (Nordenstam, Sundh, Lincoln, Svanborg, & Eden, 1989). Conversely, another study found lower colony counts acceptable for elderly men (Lipsky, Ireton, Fihn, Hackett, & Berger, 1987). The third article did not dismiss the possibility of lower counts diagnostic for women as well with further research needed in this area (Gleckman, 1992).
Polymicrobial bacteriuria. Contamination may be the most frequent cause of multiple microorganisms in the elderly (Bartlett & Treiber, 1984; Nickel & Pidutti, 1992). Nevertheless, though it is uncommon in the younger population, 25% to 33% of bacteriuria in LTCFs may be polymicrobic (Baldassarre & Kaye, 1991; Nicolle, Bjornson, Harding, & MacDonell, 1983; Nicolle, 1992). Reasons for multiple microorganisms, other than contamination, include fistulas, urinary retention, infected stones, or catheters (Nickel & Pidutti, 1992). In one study, of the 98% of catheter urine that contained high concentrations of bacteria, 78% of the cases of bacteriuria were polymicrobial (Warren, Tenney, Hoopes, Muncie, & Anthony, 1982). Polymicrobic bacteriuria has been associated with chronic infections and a higher mortality rate in both the elderly and the general population (Gross, Flower, & Barden, 1976; Mulholland & Weisman, 1987; Rudman, Hontanosas, Cohen, & Mattson, 1988; Windsor, 1983). However, at present, polymicrobic bacteriuria has not been determined to be a risk factor for the elderly.
Absence of symptoms. Asymptomatic bacteriuria (ASB) in the elderly is considered a benign and transient condition that does not require antibiotic treatment (Abrutyn et al., 1994; Eberle, Winsemius, & Garibaldi, 1993). This conclusion is based on studies showing that antibiotic treatment of ASB does not decrease morbidity or mortality in the elderly, is not effective in maintaining a sterile urine, causes side effects, and increases the incidence of reinfection and the number of drug-resistant strains of bacteria (Abrutyn et al., 1994, 1996; Mims, Norman, Yamamura, & Yoshikawa, 1990; Nicolle, Mayhew, & Bryan, 1987). Still, there are several precautions related to the recommendation of no antibiotic treatment for ASB in the elderly as shown in Table 2 (Hochreiter & Bushman, 1999; Nicolle, 1994; Nordenstam et al., 1989; Riehmann, 1998; Stamm, 1983; Zhanel, Harding, & Guay, 1990). It should be noted that the authors cited above do not share consensus with the parameters as outlined in Table 2.
Pyuria.
Pyuria indicates a host response to infecting bacteria and has been associated with the presence of both symptomatic and asymptomatic UTIs in the elderly (Aguirre-Avalos, Zavala-Silva, Diaz-Nava, Amaya-Tapia, & Aguilar-Benavides, 1999; Gleckman, 1992).
However, there are many reasons for pyuria in the elderly other than a UTI. Some researchers have found pyuria, both with ASB and without bacteriuria, to be so common in the elderly that they regard it as having questionable value, both in UTI detection and as an indication for therapy (Baldassarre & Kaye, 1991; Ouslander, Shapira, Schnelle, & Fingold, 1996; Reid & Nicolle, 1999; Rodgers et al., 1991). The issue of whether pyuria is diagnostic of a UTI has yet to be resolved. Jackson et al. (1992) and Garner et al. (1988) included pyuria as an indication of a UTI in institutionalized elderly. However, McGeer et al. (1991) rejected pyuria as being a reliable predictor of bacteriuria or symptomatic infection in this population.
Time of laboratory analysis. In the LTCF, laboratory facilities may not be readily available, causing a delay in specimen analysis (Bentley et al., 2001). Though not specific to the geriatric population, time before analysis has been discussed as a factor in assessing pyuria (Kierkegaard, Feldt-Rasmussen, Horder, Anderson, & Jorgensen, 1980; Triger & Smith, 1966). Alkaline urine, such as is caused by urease-producing pathogens, may, over time, lyse cells and lower WBC counts of specimens containing these bacteria (Gnarpe & Edebo, 1965; Nicolle, 2001; Rodgers et al., 1991). However, Anderson, Johnson, and Trombley (1994) found that only urines with pH values of 9 or greater stored for more than 4 hours were at risk for decreased WBC counts due to cell lysis.
Symptoms
Even when UTI symptoms are present in the LTCF resident, they must be recognizable symptoms to justify further analysis. The major problem confronting the nurse is addressing what changes in the resident's condition indicate the need for further evaluation of a UTI.
New or increased urgency, frequency, dysuria. Classic signs of a UTI in younger individuals (urgency, frequency, and dysuria) occur in elderly patients as well (Baldassarre & Kaye, 1991; Beier, 1999; Fune, Shua-Haim, Ross, & Frank, 1998; Jackson et al., 1992; Johnson, 1991; Nicolle, 1994; Schaeffer, 1988; Whippo & Creason, 1989; Yoshikawa, 1993). However,...
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