Open Access Research article

Paediatric Investigators Collaborative Network on Infections in Canada (PICNIC) study of aseptic meningitis

Bonita E Lee1, Rupesh Chawla2, Joanne M Langley3, Sarah E Forgie4, Mohammed Al-Hosni5, Krista Baerg6, Entesar Husain7, James Strong4, Joan L Robinson1, Upton Allen8*, Barbara J Law4, Simon Dobson7 and H Dele Davies2

Author Affiliations

1 Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada

2 Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada

3 Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada

4 Department of Pediatrics, University of Manitoba, Winnipeg, Manitoba, Canada

5 Department of Pediatrics, McGill University, Montreal, Quebec, Canada

6 Department of Pediatrics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

7 Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada

8 Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada

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BMC Infectious Diseases 2006, 6:68  doi:10.1186/1471-2334-6-68

Published: 10 April 2006



The seasonality, clinical and radiographic features and outcome of aseptic meningitis have been described for regional outbreaks but data from a wider geographic area is necessary to delineate the epidemiology of this condition.


A retrospective chart review was completed of children presenting with aseptic meningitis to eight Canadian pediatric hospitals over a two-year period.


There were 233 cases of proven enteroviral (EV) meningitis, 495 cases of clinical aseptic meningitis and 74 cases of possible aseptic meningitis with most cases occurring July to October. Headache, vomiting, meningismus and photophobia were more common in children ≥ 5 years of age, while rash, diarrhea and cough were more common in children < 5 years of age. Pleocytosis was absent in 22.3% of children < 30 days of age with proven EV meningitis. Enterovirus was isolated in cerebrospinal fluid (CSF) from 154 of 389 patients (39.6%) who had viral culture performed, and a nucleic acid amplification test for enterovirus was positive in CSF from 81 of 149 patients (54.3%). Imaging of the head by computerized tomography or magnetic resonance imaging was completed in 96 cases (19.7%) and 24 had abnormal findings that were possibly related to meningitis while none had changes that were definitely related to meningitis. There was minimal morbidity and there were no deaths.


The clinical presentation of aseptic meningitis varies with the age of the child. Absence of CSF pleocytosis is common in infants < 30 days of age. Enterovirus is the predominant isolate, but no etiologic agent is identified in the majority of cases of aseptic meningitis in Canadian children.