Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Start high‑dose steroids immediately in suspected GCA (IV if visual symptoms).
- Obtain temporal artery biopsy/ultrasound and vascular imaging; confirm diagnosis.
- Begin steroid‑sparing therapy when appropriate; monitor for relapse and large‑vessel complications.
Clinical Synopsis & Reasoning
Age ≥50 with new headache, scalp tenderness, jaw claudication, or visual symptoms. Start high‑dose glucocorticoids immediately to prevent vision loss; confirm with temporal artery biopsy or vascular imaging; consider tocilizumab or methotrexate as steroid‑sparing agents and monitor for large‑vessel involvement.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| ESR/CRP and CBC | Diagnosis | Elevated inflammatory markers; anemia | Supportive |
| Temporal artery biopsy (within 1–2 weeks of steroids) or ultrasound | Confirmation | Granulomatous arteritis or ‘halo sign’ | — |
| Vascular imaging (CTA/MRA/PET) | Extent | Aortic involvement | Baseline and follow‑up |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Visual symptoms (amaurosis, diplopia) | Vision loss imminent | Start high-dose steroids now; urgent TA biopsy |
| Aortic involvement (aneurysm/dissection) | Life-threatening | Vascular imaging and monitoring |
| Polymyalgia rheumatica overlap | Inflammatory burden | Adjust steroid plan |
| Steroid toxicity risk (diabetes/osteoporosis) | Iatrogenic harm | Bone protection; glucose plan |
| Immunosuppressed or infection concern | Masking infection | ID input; careful evaluation |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Prednisone 40–60 mg/day (or IV methylprednisolone for visual symptoms) | Glucocorticoid | Hours‑days | Prevent vision loss | Slow taper over months |
| Tocilizumab weekly or Methotrexate | Steroid‑sparing | Weeks | Reduce relapses and steroid exposure | Monitor LFTs/CBC |
| Aspirin (selected) and risk factor control | Adjuncts | Days | Reduce ischemic complications | Bleeding risk assessment |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- ACR/EULAR guidance on GCA — Link