Positive urine nitrite test: an accurate predictor of absence of pure enterococcal bacteriuria.

BACKGROUND

The aim of this study was to determine the potential ability of the urine nitrite test (NT) to predict the class of organism causing urinary tract infection.

METHODS

We retrospectively reviewed the records of all adult patients with a positive urine culture over a 6-month period. The infecting microorganisms and the urine NT results were recorded.

RESULTS

A total of 729 positive cultures met inclusion criteria. Twenty-one (11%) of the 190 gram-positive organisms and 199 (46%) of the 429 gram-negative organisms yielded a positive NT. Only 5.3% of samples with pure growth of enterococcus yielded a positive NT. The predictive value that a sample yielding a positive NT would show pure growth of enterococcus was low at 2.3%.

CONCLUSION

A positive NT is highly predictive of the absence of pure enterococcal bacteriuria.