Background: It is unclear how symptoms of urinary tract infection (UTI) influence clinical management in terms of diagnostic testing and treatment with antibiotics.
Objectives: Our aim was to assess how 11 symptoms associated with UTI related to the probability of being tested (near patient test or urine culture) or treated with antibiotics by their GP, and to see if the same 11 symptoms were associated with (i) confirmed infection from urine culture and (ii) re-consultation complaining of the same symptoms within 1 month.
Methods: A prospective cohort study of 160 patients consulting their GP with symptoms of UTI in eight general practices in Avon, UK was carried out. Association between symptoms and the probability of being (i) tested by the near patient test, (ii) tested by urine culture or (iii) treated empirically with antibiotics were examined. The association between symptoms and the probability of being treated empirically or tested (near patient test or mid-stream urine) was examined. Likelihood ratios for symptoms and near patient test results compared with two 'gold standards' for diagnosis of UTI were calculated and their impact on post-test probability of UTI determined.
Results: GPs were far more likely to treat empirically patients with symptoms of dysuria and frequency [odds ratio (OR) 6.50, 95% confidence interval (CI) 2.02-20.89] or dysuria alone (OR 5.24, 95% CI 1.62-16.95). They were far less likely to perform diagnostic tests in patients with dysuria and frequency (OR for near patient testing 0.34, 95% CI 0.14-0.83; OR for urine culture 0.15, 95% CI 0.04-0.56). The prior probabilities of UTI were 25% (positive urine culture) and 29% (re-consultation within 1 month), respectively, for each of the 'gold standards' used. Individual symptoms and near patient tests did not raise the posterior probability of UTI irrespective of which 'gold standard' was used. The most useful symptom was a history of vomiting (likelihood ratio 2.96, 95% CI 0.3-31.2), but this occurred in only three patients.
Conclusions: Current clinical practice results in a large proportion of patients receiving unnecessary antibiotic treatment. Individual symptoms of UTI are an inadequate guide on which to base diagnostic testing and antibiotic treatment decisions in primary care. Either this diagnostic inaccuracy should be acknowledged as an inevitable part of clinical practice or more accurate clinical prediction rules that incorporate symptoms, signs and near patient test results that are applicable in everyday clinical practice are required.