What is the differential diagnosis and management plan for a 70-year-old female patient presenting with right-sided headache, low-grade fevers, jaw pain, scalp and facial sensitivity, facial tenderness, and shoulder stiffness?

Giant Cell Arteritis (GCA) is the #1 Diagnosis and Requires Immediate High-Dose Corticosteroids

This 70-year-old woman with right-sided headache, low-grade fevers, jaw pain, scalp tenderness, and shoulder stiffness has Giant Cell Arteritis until proven otherwise, and treatment must begin immediately—before any diagnostic testing—to prevent irreversible blindness. 1, 2

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Top 5 Differential Diagnoses

1. Giant Cell Arteritis (GCA) - PRIMARY DIAGNOSIS

• Classic triad present: temporal headache, jaw claudication, and scalp tenderness in a patient >50 years old 1, 2
• Low-grade fever and shoulder stiffness (polymyalgia rheumatica overlap) strongly support this diagnosis 1, 3
• This is a medical emergency due to risk of permanent bilateral blindness 1, 2

2. Polymyalgia Rheumatica (PMR)

• Shoulder stiffness and constitutional symptoms fit this diagnosis 1, 3
• However, the presence of jaw claudication and scalp tenderness elevates concern to GCA, as 15-20% of PMR patients have concurrent GCA 3

3. Temporomandibular Joint Disorder (TMD)

• Jaw pain could suggest TMD, but jaw claudication (pain with chewing that resolves with rest) is pathognomonic for GCA, not TMD 1
• TMD does not cause fever, scalp tenderness, or shoulder stiffness 1

4. Trigeminal Neuralgia

• Facial pain could suggest this, but trigeminal neuralgia presents with paroxysmal sharp, electric shock-like pain lasting seconds to minutes with refractory periods—not continuous aching pain 1, 4
• No fever or systemic symptoms occur with trigeminal neuralgia 1

5. Intracranial Mass or Stroke

• New headache in elderly patient warrants consideration 1
• However, absence of focal neurological deficits, facial droop, or weakness makes this less likely 1

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Diagnostic Workup

IMMEDIATE Laboratory Tests (Draw Before Starting Treatment)

• Erythrocyte Sedimentation Rate (ESR) - typically >50 mm/hr in GCA 1, 2
• C-Reactive Protein (CRP) - markedly elevated in GCA 1, 2
• Complete Blood Count (CBC) - to assess for anemia of chronic disease 5, 3
• Comprehensive Metabolic Panel (CMP) - baseline before starting corticosteroids 3

Critical Pitfall: Do NOT delay treatment while awaiting these results—draw the labs and immediately start corticosteroids 1, 2

Temporal Artery Biopsy

• Gold standard for diagnosis but can be performed within 2 weeks after starting corticosteroids without affecting diagnostic yield 1, 2
• Arrange urgently but do not delay treatment 1, 2

Imaging

• NOT indicated as first-line when GCA is clinically suspected—neuroimaging wastes precious time 2
• Color duplex ultrasonography of temporal arteries may be helpful if biopsy unavailable, but clinical diagnosis takes precedence 3
• MRI or CT only if alternative diagnoses need exclusion after GCA treatment initiated 1

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Management of Giant Cell Arteritis (#1 Diagnosis)

Pharmacotherapy - IMMEDIATE INITIATION

High-Dose Corticosteroids (Start Immediately)

• Prednisone 40-60 mg daily orally if no visual symptoms 1, 2
• Methylprednisolone 1000 mg IV daily for 3 days if any visual disturbances present, then transition to oral prednisone 1, 2
• Treatment duration: typically 1-2 years with gradual taper beginning after 2-3 months 1, 3
• Do not wait for ESR/CRP results or biopsy confirmation 1, 2

Adjunctive Therapy

• Tocilizumab (IL-6 inhibitor) - FDA-approved for GCA, consider adding to initial corticosteroid therapy to reduce relapse rates and cumulative steroid exposure 3
• Methotrexate - may be considered as steroid-sparing agent in high-risk relapse patients 1, 3
• Low-dose aspirin 81 mg daily - consider for cardiovascular protection, though evidence is mixed 3

Monitoring During Treatment

• ESR and CRP every 2-4 weeks initially, then monthly during taper 3
• Monitor for corticosteroid adverse effects: blood glucose, blood pressure, bone density, ophthalmologic exams 3
• Approximately 50% of patients relapse during steroid taper, requiring dose adjustment 1, 3

Non-Pharmacotherapy

Immediate Consultations

• Neuro-ophthalmology or ophthalmology - urgent referral to facilitate temporal artery biopsy and monitor for visual complications 1, 2
• Rheumatology - for long-term management and steroid-sparing strategies 3

Supportive Measures

• Calcium 1200-1500 mg daily and Vitamin D 800-1000 IU daily for bone protection during prolonged corticosteroid therapy 3
• Proton pump inhibitor if high risk for peptic ulcer disease 3
• Physical therapy for shoulder stiffness from polymyalgia rheumatica component 6, 3

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Red Flags Requiring Immediate Action

Vision-Threatening Symptoms (Initiate IV Corticosteroids)

• Visual disturbances, blurred vision, diplopia, or amaurosis fugax 1, 2
• These indicate impending anterior ischemic optic neuropathy—permanent blindness can occur within days 1, 2, 7

Other Urgent Red Flags

• Sudden severe headache or change in headache pattern 1
• Tongue pain or cyanosis (lingual artery involvement) 1
• Stroke symptoms or focal neurological deficits 1

Common Pitfall: Never attribute new headache in elderly patients to migraine or tension headache without first excluding GCA 2

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Return Precautions for Patient

Instruct patient to return immediately or call 911 if:

• Any vision changes, including blurriness, double vision, or vision loss 1, 2
• Sudden severe headache or worsening headache despite treatment 1
• New weakness, numbness, or difficulty speaking 1
• Jaw pain that worsens or tongue pain develops 1

Routine follow-up:

• Return in 2-3 days to assess treatment response and review biopsy results 3
• Weekly visits initially, then every 2-4 weeks during steroid taper 3
• Report any new symptoms immediately, as approximately 50% experience relapse during taper 1, 3

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Patient Disposition

Admit to hospital if:

• Any visual symptoms present or threatened 1, 2
• Severe systemic symptoms or inability to take oral medications 3
• Need for IV corticosteroid therapy 1, 2

Discharge home if:

• No visual symptoms 3
• Able to take oral prednisone 3
• Reliable for close follow-up 3
• Ensure temporal artery biopsy scheduled within 1-2 weeks 1, 2
• Ensure ophthalmology/neuro-ophthalmology follow-up within 24-48 hours 1, 2

Critical Point: The priority is preventing permanent bilateral blindness through immediate corticosteroid therapy—this single intervention dramatically reduces morbidity and preserves quality of life 1, 2