Meningitis: a positive leukocyte-esterase test made bacterial meningitis more likely

Clinical bottom line (level 2b)

  1. Patients with CSF positive for leukocyte esterase dipstick were more likely to have bacterial meningitis (LR+19) .
DeLozier and Auerbach: Annals of Emergency Medicine 1989; 18: 1191-1198
Expires November 2003

The study

Setting: 2 acute hospitals, USA

800 patients (aged 1 month to 99 years, ?% male) providing 942 samples of CSF taken by lumbar puncture 'for routine indications'

Independent blinded reference standard, applied in all patients from a ?consecutive ?appropriate spectrum.
Reference standard:
  • CSF culture or CSF leukocytosis and 'clinical features consistent with meningitis'
Diagnostic test: leukocyte-esterase dipstick

The evidence

pre-test probability of bacterial meningitis: 4.8%, (95% CI: 3.4% to 6.1%)

diagnostic test bacterial meningitis no bacterial meningitis LR+
(95% CI)		 post-test probability LR-
(95% CI)		 post-test probability
positive or trace leukocyte-esterase dipstick 35 36 19
(14 to 28) 		49% 0.23
(0.13 to 0.40) 		1.1%
total 45 897

Comments

  1. The reference standard is rather vague, including those with a strong clinical suspicion of meningitis despite negative CSF cultures. This may falsely improve the test characteristics.

Citation

  1. DeLozier JS, and Auerbach PS: The leukocyte esterase test for detection of cerebrospinal fluid leukocytosis and bacterial meningitis. Annals of Emergency Medicine 1989; 18: 1191-1198
Contributor: Chris Ball and Clare Wotton, November 1999
Reviewer: Donald Stanley

Clinical Question.
Patient
Intervention or Exposure
Outcome