IMMEDIATE EVALUATION AND MANAGEMENT OF HEADACHE CAUSED BY LIFE-THREATENING CONDITIONS
ACUTE BACTERIAL MENINGITIS
Meningitis is a life-threatening infectious disease affecting the central nervous system (CNS). Bacteria that are pathogenic to humans can produce meningitis. However, a fairly small number of pathogens (group B streptococci, Escherichia coli, Listeria monocytogenes, Haemophilus influenzae type b, S pneumoniae, and Neisseria meningitides) account for most incidences in neonates and children. Despite antibiotic treatment, mortality is significant and some survivors will have permanent neurological sequelae. Survival depends on prompt diagnosis and antibiotic treatment (see Chapter 41).
Signs and symptoms of meningitis are age dependent. Symptoms may be nonspecific, subtle, or even absent. Older children often present with complaint of headache. Additional symptoms include fever, photophobia, nausea and vomiting, confusion, lethargy, and irritability. Physical findings include nuchal rigidity, Kernig sign (flexing the hip while extending the knee to elicit pain in the back and legs), Brudzinski sign (passive flexion of the neck causing flexion of the hips), focal neurological findings, and increased intracranial pressure (ICP). On presentation, signs of meningeal irritation are present in 75% of children with acute bacterial meningitis.
Perform lumbar puncture (LP) in a patient in which the clinical picture is suspicious for meningitis. In the absence of papilledema and focal neurological findings, computed tomography (CT) scan before LP is not indicated. Gram staining of cerebrospinal fluid (CSF) will allow presumptive identification of bacterial agent in most patients and can guide antimicrobial therapy. Bacterial meningitis is a likely diagnosis if total CSF leukocytes are more than 1000, CSF glucose is less than 10 mg/dL, and CSF protein is greater than 100 mg/dL.
If bacterial meningitis is suspected, begin administration of appropriate empiric antibiotics immediately based on age and suspected organism (see Chapter 41). Administer the first dose as soon as LP has been performed. If LP must be delayed for CT scan, obtain two blood samples for culture and begin appropriate antimicrobials. CSF culture may be negative in patients who receive antibiotic treatment before CSF has been obtained.
Studies have failed to demonstrate the usefulness of corticosteroids in patients with bacterial meningitis. However, evidence suggests a potential benefit and no prominent negative effects. National Institute for Health and Clinical Excellence (NICE) guidelines for children and young persons aged up to 16 years recommend dexamethasone 0.15 mg/kg, to a maximum dose of 10 mg, four times a day for 4 days for suspected or confirmed bacterial meningitis. Corticosteroids should not be given to children younger than 3 months. If dexamethasone was not given before or with the first dose of antibiotics, but the indication was met, the first dose should be given within ...