What are the symptoms and treatment of meningitis?

Symptoms of Meningitis

Bacterial meningitis commonly presents with fever, headache, neck stiffness, and altered mental status, but the classic triad of fever, neck stiffness, and altered mental status occurs in only 41-51% of adult patients, meaning the absence of these symptoms cannot rule out meningitis. 1

Common Presenting Symptoms in Adults

The most frequent clinical manifestations in adults include:

• Headache: Present in 58-87% of cases 2
• Fever (>38.0°C): Occurs in 77-97% of cases 1, 2
• Neck stiffness: Present in 65-83% of cases 1, 2
• Altered mental status: Reported in 30-69% of cases 1, 2
• Nausea/vomiting: Occurs in 74% of cases 1
• Petechial or purpuric rash: Identified in 20-52% of adult patients, with over 90% of rash cases indicating meningococcal infection 1, 2
• Focal neurologic deficits: Present in 15-34% of cases 1
• Coma: Occurs in 7-16% of cases 1

Common Presenting Symptoms in Children

Pediatric presentations vary by age:

• Fever: Most common symptom in 92-93% of children beyond neonatal age 2
• Headache: Reported in only 2-9% of children under 1 year, but 75% of children older than 5 years 2
• Vomiting: Occurs in 55-67% of pediatric cases 2
• Neck stiffness: Present in 40-82% of cases 2
• Altered mental status: Reported in 13-56% of cases 2
• Seizures: Occur in 9-34% of neonatal cases 2
• Petechial/purpuric rash: Present in 61% of meningococcal cases and 9% of pneumococcal cases 2

Neonatal Presentations

Neonates present with nonspecific symptoms that differ markedly from older patients:

• Irritability and poor feeding: Common nonspecific signs 2
• Respiratory distress: Frequently observed 2
• Pale or marble skin appearance: Characteristic finding 2
• Hyper- or hypotonia: Present in many cases 2
• Fever: Present in only 6-39% of neonatal cases, making it an unreliable indicator 2

Critical Diagnostic Pitfalls

The absence of classic meningeal signs does not exclude bacterial meningitis, as these signs have poor diagnostic accuracy:

• Neck stiffness sensitivity: Only 51% in children and 31% in adults 2
• Kernig sign sensitivity: 53% in children and 11% in adults 1, 2
• Brudzinski sign sensitivity: 66% in children and 9% in adults 1, 2

Grade A Recommendation: Bacterial meningitis should not be ruled out solely on the absence of classic symptoms, as characteristic clinical signs can be absent in many cases. 1

Treatment Considerations

Immediate empiric antibiotic therapy with ceftriaxone 2-4g IV daily should be initiated for suspected bacterial meningitis without delay while awaiting diagnostic confirmation, as mortality remains high in untreated cases. 3

• Adult dosing: 1-2 grams IV once daily (up to 4 grams daily for meningitis) 4
• Pediatric dosing for meningitis: Initial dose of 100 mg/kg (not exceeding 4 grams), followed by 100 mg/kg/day (not exceeding 4 grams daily) 4
• Neonatal administration: Intravenous doses should be given over 60 minutes to reduce the risk of bilirubin encephalopathy 4
• Duration: Generally 7-14 days, though complicated infections may require longer therapy 4

CSF examination should be performed unless contraindications exist, as it is essential for diagnosis when bacterial meningitis is suspected. 3, 2