What are the signs and symptoms of meningitis in adults aged 65 years or older?

Signs and Symptoms of Meningitis in Elderly Patients

Elderly patients with meningitis present differently than younger adults: they are more likely to have altered mental status (confusion, stupor, or coma) and less likely to have classic signs like fever and neck stiffness. 1

Key Clinical Differences in Elderly Patients (≥65 years)

More Common Presentations

• Altered consciousness or confusion is the predominant symptom, occurring in 88% of elderly patients compared to only 17% in younger adults 2
• The classic triad (fever, neck stiffness, altered mental status) is actually MORE common in elderly patients (58%) than in younger adults (36%) 3
• Mental status changes may be the only presenting symptom in many cases 4

Less Common Classic Signs

• Fever is absent in approximately one-third of elderly patients (present in only 67.8% of cases) 4
• Headache is absent in about half of elderly patients with meningitis 4, 2
• Neck stiffness is less frequently observed in elderly patients compared to younger adults 1, 5

Critical Symptoms to Document

All patients with suspected meningitis require documentation of the following features: 1

• Presence or absence of headache
• Altered mental status (confusion, lethargy, stupor, coma)
• Neck stiffness
• Fever
• Any type of rash
• Seizures (occur in 10-25% of adults with bacterial meningitis) 5
• Signs of shock (hypotension, prolonged capillary refill)

Physical Examination Pitfalls

Do not rely on Kernig's and Brudzinski's signs—they have only 5-11% sensitivity and miss approximately 89-95% of actual meningitis cases 1, 6

Neck stiffness has only 31% sensitivity in adults, meaning it is absent in 69% of actual cases 5, 6

Pathogen Considerations Specific to Elderly

Streptococcus pneumoniae is the most common pathogen in elderly patients (68% of cases), followed by Listeria monocytogenes 1, 3, 2

This differs from younger adults where Neisseria meningitidis predominates (50% of cases in younger adults) 3

Associated Conditions in Elderly Patients

Elderly patients frequently present with comorbid conditions: 4, 7

• Diabetes mellitus (26.6% of cases)
• Concomitant pneumonia (17.2% of cases)
• Immunocompromised status

Clinical Decision-Making Algorithm

If an elderly patient presents with ANY of the following, suspect meningitis and arrange immediate hospital transfer: 1

1. New confusion or altered mental status (most important clue in elderly)
2. Fever with any neurologic change
3. Headache with altered consciousness
4. Any combination of fever, headache, neck stiffness, or altered mental status

The absence of classic signs does NOT exclude meningitis—95% of patients have at least two of four cardinal symptoms (headache, fever, neck stiffness, altered mental status), but individual symptoms are poor discriminators 5, 8

Urgency and Prognosis

Elderly patients with bacterial meningitis have significantly higher mortality (34-51.5%) compared to younger adults (13%) 3, 4, 7

All suspected cases require emergency ambulance transport with arrival at hospital within one hour of initial assessment 1

The interval from admission to antibiotic initiation is longer in elderly patients, contributing to worse outcomes—do not delay treatment while awaiting diagnostic confirmation 7

Common Diagnostic Pitfalls to Avoid

• Do not dismiss meningitis because fever or neck stiffness is absent 1, 4
• Do not wait for classic symptoms—confusion alone in an elderly patient warrants consideration of meningitis 4, 2
• Do not rely on negative Kernig's or Brudzinski's signs to rule out disease 1, 6
• Maintain high index of suspicion in elderly patients with any new neurologic sign or change in mental status 4, 2