Signs of meningeal irritation at the emergency department: how often bacterial meningitis?

OBJECTIVE: Although signs of meningeal irritation are highly indicative of meningitis, they are not pathognomonic. In this study, we described the final diagnoses in children with signs of meningeal irritation, and we assessed the frequency of bacterial meningitis related to specific signs of meningeal irritation.
METHODS: Information was collected from records of 326 patients (aged 1 month to 15 years) who visited the emergency department of the Sophia Children's Hospital between 1988 and 1998 with signs of meningeal irritation, assessed by either the general practitioner or the pediatrician.
RESULTS: Bacterial meningitis was diagnosed in 99 patients (30%), viral or aseptic meningitis in 43 (13%). Other diagnoses were pneumonia (8%), other serious bacterial infections (2%), and upper respiratory tract infections or other self-limiting diseases (46 %). Presence of one of the signs of meningeal irritation assessed by the pediatrician was related to bacterial meningitis in 39%. Specific tests eliciting meningeal irritation, such as Brudzinski's and Kernig's signs, were not related to a higher frequency of bacterial meningitis than neck stiffness and the tripod phenomenon. In children < or =1 year, bacterial meningitis is more frequently related to presence of irritability and a bulging fontanel.
CONCLUSION: Bacterial meningitis is present in 30% of children with signs of meningeal irritation. Presence of meningeal irritation as assessed by the pediatrician is related to bacterial meningitis in 39%. A better prediction of bacterial meningitis was not achieved by using more specific tests for signs of meningeal irritation.