Clinical Presentation:
- Headache (often new or worsening), scalp tenderness, jaw claudication, visual symptoms (e.g., amaurosis fugax, blindness).
- Systemic symptoms: fever, weight loss, fatigue, myalgia.
- Physical exam: tender, pulseless temporal arteries, possible visual deficits.
- Diagnostic Workup:
- Labs: Elevated ESR (>40 mm/hr), CRP (high sensitivity, but 10% of cases may have normal values).
- Imaging: Ultrasound (halo sign), MRI/MRA (arterial wall thickening), PET/CT (if systemic involvement suspected).
- Biopsy: Temporal artery biopsy (gold standard, but false negatives possible if delayed; consider bilateral biopsy if initial negative).
- Treatment:
- High-dose glucocorticoids (e.g., prednisone 40–60 mg/day) immediately to prevent vision loss.
- Taper slowly (over months) with monitoring of symptoms and ESR/CRP.
- Adjuncts: Consider tocilizumab (IL-6 inhibitor) for refractory cases or to reduce steroid burden (per EULAR guidelines).
- Rationale:
- Rapid glucocorticoid initiation is critical due to risk of irreversible blindness.
- Biopsy should be performed within 48 hours of steroid initiation for best yield.