Primary Headaches other than migraine

I. Classification (ICHD-3)

While Migraine is the most discussed pediatric headache, other primary headaches are significant causes of morbidity. They are classified based on the International Classification of Headache Disorders, 3rd Edition (ICHD-3).

1. Tension-Type Headache (TTH): The most common primary headache.
2. Trigeminal Autonomic Cephalalgias (TACs): Rare in children, distinct autonomic features.
3. Other Primary Headaches: Stabbing, Cough, Exertional, etc.
4. New Daily Persistent Headache (NDPH): A unique entity relevant to adolescents.

II. Tension-Type Headache (TTH)

Prevalence: The most common headache type in children/adolescents (10–25% prevalence).

1. Pathophysiology

• Multifactorial: Peripheral activation of myofascial nociceptors (pericranial muscle tenderness) combined with central sensitization.
• Triggers: Psychosocial stress (school/family), sleep deprivation, dehydration, hunger, poor posture.

2. Clinical Features

• Location: Bilateral (Holocranial or Frontal/Occipital).
• Quality: Pressing, tightening, or "band-like" sensation (Non-pulsating).
• Intensity: Mild to moderate (does not prohibit activity).
• Aggravation: NOT aggravated by routine physical activity (unlike migraine).
• Associated Symptoms:
  • No vomiting (mild nausea allowed).
  • No photophobia OR phonophobia (one is allowed, but not both).
• Duration: 30 minutes to 7 days.

3. Classification of TTH

• Infrequent Episodic: <1 day/month.
• Frequent Episodic: 1–14 days/month.
• Chronic TTH: $\ge$ 15 days/month for >3 months. (Often associated with comorbidity like anxiety/depression).

4. Management

• Acute Treatment:
  • Analgesics: Ibuprofen (10 mg/kg), Naproxen (5–10 mg/kg), or Paracetamol (15 mg/kg).
  • Caution: Limit use to <2–3 days/week to prevent Medication Overuse Headache (MOH).
• Preventive Treatment: (Indicated for Chronic TTH or frequent episodic affecting QoL).
  • Amitriptyline (TCA): First-line. Start 0.25–0.5 mg/kg at night.
  • Topiramate: Alternative.
• Non-Pharmacologic (Crucial):
  • Cognitive Behavioral Therapy (CBT).
  • Sleep hygiene, hydration.
  • Biofeedback and relaxation techniques.

III. Trigeminal Autonomic Cephalalgias (TACs)

Characterized by unilateral headache in the trigeminal distribution + ipsilateral cranial autonomic features. Rare in prepubertal children; incidence rises in adolescence.

1. Cluster Headache

• Epidemiology: Male predominance (>10 years age).
• Clinical Features:
  • Pain: Severe, strictly unilateral, orbital/supraorbital/temporal.
  • Duration: 15–180 minutes (untreated).
  • Frequency: Attacks occur in "clusters" (1 every other day to 8/day) for weeks, followed by remission.
  • Autonomic Signs (Ipsilateral): Lacrimation, conjunctival injection, nasal congestion/rhinorrhea, eyelid edema, forehead sweating, miosis/ptosis.
  • Behavior: Patient is restless/agitated (paces around, rocks head) – distinct from migraineurs who lie still.
• Management:
  • Abortive: High-flow Oxygen (100% via non-rebreather mask at 10–15 L/min). Sumatriptan (Subcutaneous or Intranasal).
  • Preventive: Verapamil (monitor ECG), Topiramate, Lithium (rarely used in kids due to toxicity). Bridge therapy with oral steroids.

2. Paroxysmal Hemicrania (PH)

• Features: Similar to Cluster but shorter duration (2–30 mins) and higher frequency (>5 attacks/day).
• Diagnosis: Absolute responsiveness to Indomethacin.
• Treatment: Indomethacin (1–2 mg/kg/day).

3. SUNCT / SUNA

• Short-lasting Unilateral Neuralgiform headache attacks: Very rare in children.
• Duration: Seconds to minutes ("saw-tooth" pattern).
• Treatment: Lamotrigine, Topiramate. (Indomethacin resistant).

IV. New Daily Persistent Headache (NDPH)

A diagnosis of exclusion, typically seen in adolescents.

• Criteria:
  • Headache becomes daily and unremitting within 24 hours of onset.
  • Lasts >3 months.
  • "I remember the exact day it started."
  • Pain can have Migraine or TTH features.
• Precipitant: Often follows a viral illness (EBV) or stressful life event, but often idiopathic.
• Management: notoriously refractory.
  • Aggressive treatment with Topiramate, Gabapentin, or Amitriptyline.
  • Inpatient protocols (IV DHE, IV Valproate) may be required.

V. Other Primary Headaches (The "Miscellaneous" Group)

These are diagnoses of exclusion. Neuroimaging is mandatory to rule out structural causes (e.g., Chiari malformation, posterior fossa tumors) before diagnosing these in children.

1. Primary Stabbing Headache ("Ice-pick Headache")

• Pain: Transient, single or multiple stabs (<3 seconds).
• Location: V1 distribution (orbital/temple).
• Treatment: Reassurance (usually benign). Indomethacin if frequent.

2. Primary Cough Headache

• Precipitant: Coughing, sneezing, straining (Valsalva).
• Red Flag: Must rule out Chiari Malformation Type I (hindbrain herniation).
• Treatment: Indomethacin (if MRI is normal).

3. Primary Exercise (Exertional) Headache

• Precipitant: Sustained physical exercise.
• Duration: 5 mins to 48 hours.
• Treatment: Indomethacin taken before exercise; Propranolol.

4. Primary Thunderclap Headache

• Definition: Severe headache peaking in <1 minute.
• Action: Emergency MRI/MRA and LP mandatory to rule out SAH (Subarachnoid Hemorrhage) or RCVS (Reversible Cerebral Vasoconstriction Syndrome).

VI. Summary of Indomethacin-Responsive Headaches

A key exam concept. These headaches respond dramatically to Indomethacin:

1. Paroxysmal Hemicrania.
2. Hemicrania Continua.
3. Primary Stabbing Headache.
4. Primary Cough/Exertional Headache.