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Accuracy of negative dipstick urinalysis in ruling out urinary tract infection in adults

Three Part Question

In [adults with symptoms of a urinary tract infection] does [negative dipstick urinalysis] rule out a [UTI]?

Clinical Scenario

A 20 year old student presents to the emergency department with a three day history of urinary frequency, dysuria and lower abdominal pain. Examination is unremarkable and dipstick urinalysis is normal. You wonder whether normal dipstick urinalysis is sufficient to rule out a UTI, or whether antibiotics anyway should be prescribed whatever the result.

Search Strategy

Medline 1966-04/03 using the OVID interface.
[(exp Urinalysis OR exp Indicators and Reagents OR exp Reagent Strips OR OR AND (exp Urinary Tract Infections OR (urin$ adj5 infect$).af OR OR exp Bacteriuria OR bacteriur$.af) AND ( OR OR OR OR OR] LIMIT to human AND English language AND all adult <19 plus years>

Search Outcome

75 papers were found. Of these, 2 were identified as answering the three part question. One of these was a meta-analysis containing 9 papers not identified by the original search as they did not consider dipstick urinalysis.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Bent S et al,
Adult women from 9 original studies involving patients with symptoms of an UTI presenting to outpatient clinics. Total number of patients 2331 Positive dipstick defined as detectable nitrite or leukocyte esterase Prevalence 48% Gold standard of positive urine culture Meta-analysisSensitivity75%Some studies only included women Only able to use data from some studies Difference in cut-off level for positive urine culture (range 100-100,000 CFU/ml) Some studies of poor quality
Likelihood of UTI in prescence of dysuria and frequency without vaginal discharge is high>90%
Lammers RL et al,
331 adult women presenting to ED or intermediate care centre with more than 1 symptom of a UTI Positive dipstick defined as detectable nitrite or leukocyte esterase Prevalence 45.9% Gold standard urine cultureProspective observational studySensitivity92%Only women No sample size analysis


The meta-analysis shows that the prevalence of UTI in patients who present with symptoms of UTI is around 50%. The probability of UTI is even higher (around 90%) with a convincing history. Dipstick urinalysis is a quick and inexpensive test however sensitivity (and therefore negative predictive value) were found to be as low as 75%. Some studies included in the meta-analysis were of low quality and further studies need to be done in this field.

Clinical Bottom Line

Dipstick urinalysis is of insufficient sensitivity to be used to rule out UTI in patients with one or more symptoms.


  1. Bent S, Nallamothu BK, Simel DL et al. Does this woman have an acute uncomplicated urinary tract infection? JAMA 2002;287(20):2701-2710.
  2. Lammers RL, Gibson S, Kovacs D et al. Comparison of test characteristics of urine dipstick and urinalysis at various test cutoff points. Ann Emerg Med 2001;38:505-12.