[Aseptic meningitis in an adult population. Etiology and utility of molecular techniques in the clinical management of patients].

Objective: This study describes the epidemiological, clinical and microbiological features of acute aseptic meningitis (AAM) in an adult population, and evaluates the impact of microbiological results on the clinical management of patients.

Patients And Methods: Cases of AAM were prospectively collected between 2007 and 2010 among immunocompetent patients over 14 years-old. Enteroviruses and herpes viruses were determined using nucleic acids detection in CSF. Demographic and clinical data were retrospectively collected from medical records.

Results: A total of 94 patients were included, of whom 84 were diagnosed with viral meningitis (VM). The annual incidence of VM ranged from 2.4 to 15.3 cases per 100,000 inhabitants. An aetiological diagnosis was obtained in 76.2% of the patients with VM, 55 enterovirus, 4 HSV-2, 3 VZV, one HSV-1, and one EBV. Forty five per cent of patients were admitted to hospital and 65.8% of them received antibiotic treatment. A positive result prompted immediate discharge of 80% of inpatients and discontinuation of antibiotic therapy in 94.1% of them. The median duration of admission to hospital in these patients was 2.8±2.9 days. Patients without available results during admission completed the antibiotic treatment, and the median hospital stay was 11.6±4.6 days.

Conclusions: The annual incidence of AAM is variable. Enteroviruses were the main aetiological agent. Molecular tests revealed the aetiology in 76.2% of cases. Almost half of the patients required hospitalisation, and in these cases a positive result can lead to the immediate discharge of patients, and the diagnostic and therapeutic interventions can be reduced.