Table 4.
From The Rational Clinical Examination: Univariate Findings and Multivariate Approach for Diagnosing UTI in Adult Womena,b
| Univariate Findingsc | LR (95% CI)d | |
|---|---|---|
| Present | Absent | |
| Dysuria | 1.5 (1.2–2.0) | 0.5 (0.3–0.7) |
| Frequency | 1.8 (1.1–3.0) | 0.5 (0.4–1.0) |
| Vaginal discharge | 0.3 (0.1–0.9) | 3.1 (1.0–9.3) |
| Vaginal irritation | 0.2 (0.1–0.9) | 2.7 (0.9–8.5) |
| Abnormal | Normal | |
| Dipstick resulte | 4.2 | 0.3 |
Abbreviations: LR, likelihood ratio; UTI, urinary tract infection.
A Rational Clinical Examination article evaluated the efficacy of various clinical features and urine dipstick testing for younger patients. The approach for older patients is different. Although the prevalence of asymptomatic bacteriuria in the general population is approximately 5%, it ranges from 15% to 17% in women older than 70 years and can be as high as 30%–50%. Chronic genitourinary symptoms, such as urinary frequency and urgency, are also very common in older women. It is important to distinguish between chronic symptoms and new or worsening urinary symptoms. In general, vaginal discharge is not a common presenting complaint among older women with or without a UTI. Considering these challenges, establishing a diagnosis in older women requires the presence of 2 clinical features such as fever, worsened urinary urgency or frequency, acute dysuria, suprapubic tenderness, costovertebral angle pain or tenderness, and the presence of bacteriuria or pyuria on urinalysis. Although not a common complaint, new dysuria is a very sensitive indicator of symptomatic UTI in older women.
Adapted from The Rational Clinical Examination: Evidence-Based Clinical Diagnosis.31 Data were derived from Bent et al.32
For a multivariable approach, multiply the above individual LRs for combinations of findings (eg, dysuria present and vaginal discharge absent yields a combined LR = 4.7; dysuria absent and vaginal discharge present yields a combined LR = 0.15).
LRs that are less than 1 are rounded off to make computation easier when combining findings.
The dipstick values were selected from visual inspection of a summary receiver-operating characteristic curve to maximize the accuracy so CIs could not be determined.33