What is the appropriate workup for a patient with a persistent consistent headache?

Workup for Persistent Consistent Headache

For patients with persistent consistent headaches, a focused evaluation for red flags is essential, followed by appropriate neuroimaging when indicated by concerning features such as atypical headache patterns, neurological signs, increasing frequency, nocturnal symptoms, abrupt onset, or headache following trauma. 1

Initial Assessment: Red Flag Identification

The initial evaluation should focus on identifying red flags that suggest secondary headache disorders requiring urgent attention:

• Concerning features requiring neuroimaging:
  • Atypical headache patterns
  • Presence of neurological signs
  • Rapidly increasing frequency
  • History of uncoordination
  • Headache that awakens patient from sleep
  • Abrupt onset of severe headache
  • Marked change in headache pattern
  • Persistent headache following head trauma 1
  • Focal neurologic signs
  • Papilledema
  • Neck stiffness
  • Immunocompromised state
  • Sudden onset of "worst headache of life"
  • Personality changes
  • Headache worsening with exercise 2

Diagnostic Workup Algorithm

1. Detailed Headache Characterization:

   • Location, quality, severity, duration
   • Associated symptoms
   • Frequency and pattern
   • Aggravating and alleviating factors
   • Medication use history 1

2. Physical and Neurological Examination:

   • Complete neurological assessment
   • Vital signs (particularly blood pressure)
   • Fundoscopic examination for papilledema
   • Assessment for meningeal signs

3. Neuroimaging:

   • When to order:
     • Any red flags identified above
     • Uncertain diagnosis
     • Poor response to appropriate treatment 3
   • Type of imaging:
     • Head CT without contrast if intracranial hemorrhage suspected
     • MRI preferred for most other dangerous causes 2, 4

4. Laboratory Testing:

   • CBC, ESR, CRP if inflammatory cause suspected
   • Lumbar puncture if subarachnoid hemorrhage or meningitis suspected
   • EEG only if seizure disorder suspected 1

Diagnostic Criteria for Primary Headaches

After excluding secondary causes, apply these diagnostic criteria:

1. Migraine without aura:

   • ≥5 attacks lasting 4-72 hours
   • At least 2 characteristics: unilateral location, pulsating quality, moderate/severe intensity, aggravation by activity
   • At least 1 symptom: nausea/vomiting, photophobia and phonophobia 1

2. Migraine with aura:

   • ≥2 attacks with reversible aura symptoms
   • Each aura symptom lasting 5-60 minutes
   • Headache following aura within 60 minutes 1

3. Chronic migraine:

   • Headache on ≥15 days/month for >3 months
   • Migraine features on ≥8 days/month 1

4. Medication overuse headache:

   • Headache on ≥15 days/month
   • Regular overuse of acute headache medication (non-opioid analgesics ≥15 days/month or other medications ≥10 days/month) for >3 months 1

Common Pitfalls to Avoid

• Failing to recognize medication overuse headache in patients with daily or near-daily headaches 1
• Missing chronic migraine diagnosis (only 20% of patients who fulfill criteria are correctly diagnosed) 1
• Confusing migraine aura with transient ischemic attack 1
• Misdiagnosing "sinus headache" when symptoms are actually migraine with autonomic cranial symptoms 1
• Neglecting to identify secondary headache causes in patients with concerning features 4

When to Refer to Neurology

Referral to a neurologist is indicated for:

• Cluster headache
• Headache of uncertain diagnosis
• Poor response to preventive strategies
• Migraine with persistent aura
• Headache with associated motor weakness 3

The most recent evidence emphasizes that while most headaches are primary in nature, careful screening for red flags is essential to identify potentially life-threatening secondary etiologies that require prompt evaluation and management 4.