Stephen J.LurieMD, PhD, Senior EditorIndividualAuthor
In Reply: We agree with Drs Hay and Fahey that
the correct use of diagnostic tests requires an accurate assessment of a patient's
pretest probability of disease. They were concerned that our reported pretest
probability of disease (48%) was too high. They cite 2 other studies,1,2 both with a lower prevalence
of UTI in women presenting with symptoms. Unfortunately, we cannot evaluate
the first study,1 which is not yet published.
Dobbs and Fleming2 did not perform urine
cultures on all patients, but instead performed a urine dipstick test on all
urine samples, and then performed cultures only when the dipstick result was
positive. Since the dipstick test is not as sensitive as a standard culture,
this method underestimates the true prevalence of UTI.
Bent S, Nallamothu BK, Fihn SD, Saint S. Clinical Diagnosis of Urinary Tract Infection—Reply. JAMA. 2002;288(10):1229-1231. doi:10.1001/jama.288.10.1229