Chronic daily headache: when to suspect meningitis.

Millions of patients see physicians each year for headache, most of which are primary headaches. However, serious secondary headaches, such as meningitis, represent about 5% of children and 1% to 2% of adults seen in the emergency department for headache. A primary care or emergency department physician may initially miss individuals with bacterial meningitis. Considering meningitis as a headache cause is important because delay in the diagnosis may have adverse consequences. A careful history and physical examination are central in identifying individuals at high risk for meningitis. This article lists information that can be obtained from the patient that may be indicative of meningitis. Performing a lumbar puncture with appropriate examination of the cerebrospinal fluid (CSF) is the key to establishing the diagnosis of meningitis. This article also includes the types of meningitis that should be considered when the CSF demonstrates a pleocytosis.