II. Epidemiology
- Closely associated with Polymyalgia Rheumatica
- Polymyalgia is present in 27-53% of those with Temporal Arteritis
- Prevalence: 500 per 100,000 over age 50 years
- Rarely occurs under age 50 years
- Average age of presentation: 72 years (peak age 70-80 years old)
III. Pathophysiology
- Inflammation of medium and large arteries originating from aortic arch
- Most commonly affects external Carotid Artery branches (esp. temporal artery, occipital artery)
- Infiltration of arterial wall with inflammatory cells
- Localized to elastic laminae
- May extend to panarteritis
- Intima thickens results in lumen narrowing, Occlusion
- Causes Arteritic Ischemic Optic Neuropathy
IV. Symptoms
- See Polymyalgia Rheumatica for rheumatologic symptoms
- Onset of symptoms
- Insidious over months or
- Sudden Onset
- New Onset Headache (LR+ 3.6, LR- 0.43)
- Test Sensitivity >50 to 70%
- Test Specificity 82%
- Over temporal or occipital arteries (but may occur elsewhere)
- Boring ache of moderate intensity with minimal relief from Analgesics
- Scalp tenderness, and touch may provoke Headache
-
Jaw Claudication (LR+ 20, LR- 0.62)
- Test Sensitivity: 39%
- Test Specificity: 98%
- Facial Muscle pain or weakness with chewing and relieved with rest
- May be atypical with tooth, sinus, Tongue or Ear Pain
- Visual symptoms (LR+ 2.5, LR- 0.81)
- Test Sensitivity: 28%
- Test Specificity: 89%
- May precede permanent Vision Loss by hours or days
- Vision may be partially obscured
- Visual Field cuts
- Diplopia
- Acute Vision Loss or Amaurosis Fugax
- Systemic symptoms (at least one systemic symptom occurs in 75% of patients)
- Fever of Unknown Origin
- Malaise
- Fatigue
- Anorexia
- Weight loss
- Respiratory and other symptoms (10% of cases)
- Sore Throat
- Dry Cough
- Tongue Pain (or tongue Claudication)
- Pharyngitis
- Dysphagia
- Choking Sensation
- Lower extremity Claudication
V. Signs
- See Polymyalgia Rheumatica for rheumatologic findings
- Tenderness or Hypersensitivity over temporal or occipital arteries or scalp (LR+ 21, LR- 0.6)
- Test Sensitivity: 41%
- Test Specificity: 98%
- Temporal artery abnormalities (LR+ 19, LR- 0.44)
- Test Sensitivity: 57%
- Test Specificity: 97%
- Palpate superior to ear tragus and compare to contralateral side
- Pulse reduction
- Nodular, beaded or thickened
- Eye Exam to exclude other causes of Vision change
- Cardiovascular Exam (large vessels including the aorta may be affected)
- Peripheral pulses (evaluate for symmetry, esp. between radial pulses)
- Complete Neurologic Exam
- Evaluate for neurologic deficits suggestive of Cerebrovascular Accident
VI. Complications
- Sudden Vision Loss (Anterior Ischemic Optic Neuropathy)
- Occurs in 8-15% of Temporal Arteritis patients
- See Amaurosis Fugax
- Secondary to narrowing of arterial lumens
- Ophthalmic terminal branches
- Posterior ciliary arteries
- Visual deficit is permanent
- May be preceded by visual changes or Headaches by hours or days
- Contralateral eye is typically affected within 1-2 weeks (requires prompt management)
VII. Associated Conditions
- Polymyalgia Rheumatica (50%)
- Jaw Claudication (see above)
- Aorta involvement (15% of cases)
- Aortic Arch Syndrome
- Vertebrobasilar Artery thrombosis
- Upper extremity Claudication
- Raynaud Phenomenon
- Thoracic Dissection
- Myocardial Infarction
- Mesenteric Infarction
VIII. Differential Diagnosis
- Jaw Claudication
-
Vision Changes
- Optic Neuritis
- Retinal Artery Occlusion
- Embolic conditions (e.g. endocarditis)
- Facial Pain
-
Headache or other Neurologic Findings
- Small and medium vessel Vasculitis (e.g. Polyarteritis Nodosa, drug-induced Vasculitis)
- Migraine Headache
- Trigeminal Neuralgia
- Cerebrovascular Accident
- Meningitis
- Encephalitis
- Malignancy (Brain Mass, Lymphoma, Multiple Myeloma)
- Hypothyroidism
IX. Diagnosis
- Precautions
- Strongly consider GCA in over age 60 years old with sudden onset Vision Loss or Diplopia (including transient)
- Delayed treatment may result in blindness
- Start Corticosteroids immediately when diagnosis suspected
- Do not wait for biopsy results prior to starting Corticosteroids
- Obtain biopsy within 2 weeks of starting Corticosteroids (first 2-3 days preferred)
- Temporal Artery Biopsy
- Biopsy shows chronic inflammation, necrotizing arteritis
- Mononuclear cell predominance OR
- Granulomatous process with multinucleated giant cells
- Obtain at least 1 cm sample from most symptomatic side
- Long biopsy specimens (>2 cm) are preferred
- Test Sensitivity: 80-92%
- False Negative Rate up to 20%
- Consider biopsy of contralateral side if negative biopsy despite high clinical suspicion
- Consider empiric treatment despite negative biopsy if high clinical suspicion
- Biopsy positive for 2 weeks after starting Prednisone
- Biopsy is best within 48 to 72 hours
- Biopsy shows chronic inflammation, necrotizing arteritis
- Findings most suggestive of Temporal Arteritis
- Beaded (nodular thrombus) temporal artery (+LR 4.6)
- Prominent temporal artery (+LR 4.3)
- Jaw Claudication (+LR 4.2)
- Diplopia (+LR 3.4)
- Temporal artery pulse absent (+LR 2.7)
- Temporal artery tender (+LR 2.6)
- Smetana (2002) JAMA 287:92-101 [PubMed]
- American College of Rheumatology criteria (3 of 5 criteria required)
- Age 50 years or older
- Localized Headache of new onset
- Tenderness or decreased pulse over the temporal artery
- ESR 50 mm/h or higher
- Temporal artery biopsy with necrotizing arteritis (see findings above)
X. Labs
- See Polymyalgia Rheumatica for complete lab evaluation of differential diagnosis
- Acute phase reactants
- Obtain both ESR and C-RP
- Test Sensitivity approaches 99% in Temporal Arteritis when both are obtained
- Erythrocyte Sedimentation Rate (ESR, Westergren) Increased
- See Polymyalgia Rheumatica for interpretation
- ESR typically >50 mm/h (averages 83 mm/h in Temporal Arteritis, often >100 mm/h)
- However, ESR <50 mm/h does NOT completely exclude Temporal Arteritis
- Age based cut-offs
- Men: Age/2
- Women: (Age + 10)/2
- C-Reactive Protein increased
- Higher Test Sensitivity than ESR for initial diagnosis
- No well defined cut-off criteria (unlike ESR with cutoff of 50 mm/h)
- Interleukin-6
- May be elevated in new or recurrent GCA and returning to normal with remission
- Consider when ESR and C-RP are normal despite high clinical suspicion
- Obtain both ESR and C-RP
- Nonspecific Lab findings
- Moderate normocytic, normochromic Anemia
- Thrombocytosis
- Decreased Serum Albumin
- Increased Alkaline Phosphatase (50% of cases)
XI. Imaging
- Indications
- Strong clinical suspicion for GCA, but negative biopsy or biopsy unavailable
-
Doppler Ultrasound of temporal artery
- Positive (abnormal) if noncompressible, hypoechoic temporal artery with wall thickening
- Sufficient for Temporal Arteritis diagnosis if positive
- Luqmani (2016) Health Technology Assessment
- Karassa (2005) Ann Intern Med 142(5): 359-69 [PubMed]
- Aranda-Valera (2017) Clin Exp Rheumatol 35 Suppl 103(1):123-127 +PMID:28244857 [PubMed]
- Other advanced imaging studies
- Fluorodeoxyglucose PET Scan
- MRI
- CT Aortic Survey (or MRI equivalent)
- Consider aortic imaging for symptoms or signs of large vessel involvement
- Consider in all new GCA cases (esp. if comorbid Hypertension)
XII. Management
- Urgent referral to rheumatology in all cases
- Do not delay starting if high level of suspicion
- Biopsy within 2 weeks of starting Corticosteroids (best within first 48-72 hours)
- Alternatively, temporal artery Ultrasound may be performed
-
Corticosteroids
- Starting Dose
- No visual symptoms or Jaw Claudication
- Prednisone 40-60 mg (at least 0.75 mg/kg) orally daily
- Consider 40 mg instead of 60 mg orally daily for those with Diabetes Mellitus
- Visual symptoms (e.g. Amaurosis Fugax), Jaw Claudication or other critical cranial ischemia
- Solumedrol 250 mg every 6 hours for 3 days
- Following solumedrol course, switch to oral Prednisone 60 mg orally daily (as above)
- Established Vision Loss
- Prednisone 60 mg (at least 0.75 mg/kg) orally daily
- Protects the contralateral, unaffected eye
- No visual symptoms or Jaw Claudication
- Taper protocol (typically after 4-8 weeks on initial dose)
- Start tapering after 4 weeks on Prednisone AND symptom resolution and ESR/CRP normalization
- Taper dose by 10 mg every 2 weeks until 20 mg dose is reached, then
- Taper dose by 2.5 mg every 2-4 weeks until 10 mg dose is reached, then
- Taper dose by 1 mg every 1-2 months
- Anticipate low dose (10 mg) reached by 6 months
- Efficacy
- Course
- Continue Prednisone 1-2 years if ocular complications
- Prednisone may require continuation up to 5 years in some cases
- Starting Dose
- Adjuvant medications
- Tocilizumab (Actemra)
- Monoclonal Antibody associated with significant sparing of Corticosteroids
- Dosed weekly or to every other week
- Unizony (2012) Arthritis Care Res 64(11):1720-9 +PMID:22674883 [PubMed]
- Aspirin 81 mg orally daily
- Concurrent Methotrexate is not typically recommended (unlike Polymyalgia Rheumatica)
- However its use, along with Biologic Agent are left to local expert opinion (e.g. rheumatology)
- Tocilizumab (Actemra)
- Prevention of Bone Mineral Density Loss due to Corticosteroids (e.g. Prednisone)
- See Corticosteroid Associated Osteoporosis
- Vitamin D Supplementation
- Calcium Supplementation
- Consider DEXA Scan
- Consider Bisphosphonates
- Other Prevention of complications from Corticosteroids (e.g. Prednisone)
- See Polymyalgia Rheumatica
- Consider Gastrointestinal Prophylaxis (e.g. Omeprazole or other Proton Pump Inhibitor)
XIII. Management: Follow-up
- Rheumatology consult
- One week after starting steroids, then
- Three weeks after starting steroids, and then
- Six weeks
- Rheumatology or primary care
- Visit at 3 months, 6 months, 9 months and 12 months
- Labs (each visit)
- Complete Blood Count
- Erythrocyte Sedimentation Rate (ESR)
- C-Reactive Protein (C-RP)
- Basic chemistry panel (Electrolytes, Renal Function tests, and Serum Glucose)
- Imaging
- Chest XRay to assess aortic root every 2 years
- Evaluation
- Relapse symptoms
- Fever without other cause
- New or Recurrent Headache, sclp tenderness, Jaw Claudication or Vision change
- Extremity Claudication, CVA symptoms
- Proximal Muscle pain (Shoulder or pelvic girdle) or Morning stiffness
- Fatigue
- Adverse effects to treatment (Corticosteroid adverse effects)
- Gastritis or Peptic Ulcer
- Bone density
- Hyperglycemia
- Relapse symptoms
XIV. Course
- Self limited course over months to years with Corticosteroids
- Increased mortality related to other regions of Vasculitis
- Risk of permanent blindness if untreated
- Contralateral eye is typically affected within 1-2 weeks (requires prompt management)
XV. References
- Shoenberger and Ishimori in Herbert (2015) EM:Rap 15(5): 7-8
- Buttgereit (2016) JAMA 315(22): 2442-58 [PubMed]
- Caylor (2013) Am Fam Physician 88(10):676-84 [PubMed]
- Dasgupta (2010) Rheumatology 49(8): 1594-7 [PubMed]
- Hellmann (2002) JAMA 287:2996-3000 [PubMed]
- Loddenkemper (2004) Arch Neurol 61:1620-2 [PubMed]
- Raleigh (2022) Am Fam Physician 106(4): 420-6 [PubMed]
- Selvarani (2002) N Engl J Med 347:261-71 [PubMed]
- Unwin (2006) Am Fam Physician 74:1547-58 [PubMed]
- Weyand (2003) Ann Intern Med 139:505-15 [PubMed]