Background: To know the frequency, indications and diagnosis efficiency of lumbar puncture (LP) in the Emergency Department (ED) when suspecting a central nervous system (CNS) infection.
Patients and method: We analyzed all the LP performed over a 2-year period in the ED. We compared the clinical characteristics of patients with and without CNS infection. We also reviewed all the cases of CNS infection diagnosed in the hospital in the same period.
Results: A LP was performed in 0.4% of emergencies. In 76% of cases, it was performed because of CNS infection suspicion, which was confirmed in 30% of cases. Fever, headache, nuchal rigidity and chronical otitis were all clinical variables associated with CNS infection. An 80% of CNS infections that were not diagnosed in the ED corresponded to HIV-infected patients.
Conclusions: Lumbar puncture is frequently performed in the ED, mostly for suspicion of CNS infection, which is eventually confirmed in one third of cases. CNS infection cases which have not been suspected in the ED usually correspond to a subacute meningitis in a HIV-infected patient.