Temporal arteritis

Disease Description (Causes and Symptoms)

• Definition and pathophysiology: Giant cell arteritis (temporal arteritis) is a granulomatous inflammatory disease of medium- and large-sized arteries, including the external branches of the aortic arch and the intracranial and extracranial supplying vessels. Immune-mediated inflammation causes infiltration of giant cells, monocytes, and lymphocytes into the intima and media of blood vessels, resulting in vascular stenosis and ischemia. The aorta and its branch vessels (such as branches of the carotid artery) are also commonly involved, creating a risk of aortic aneurysm.
• Age at onset and epidemiology: Occurs mainly in people aged 50 and older (mean age at onset is in the 70s), women > men, and is more common in people of Northern European descent. Frequently accompanied by polymyalgia rheumatica (approximately 30–50%).
• Main symptoms:
  • Headache (temporal pain), tenderness of the temporal artery, or a palpable nodule
  • Jaw claudication (jaw pain/fatigue while eating)
  • Sudden decrease in vision, transient visual disturbances (curtain-like vision or amaurosis fugax), ischemic optic neuropathy → risk of permanent blindness
  • Fever, weight loss, decreased appetite, general malaise
  • Muscle stiffness/pain (shoulder and pelvic regions) — symptoms of PMR
• Summary of test findings: Markedly elevated ESR and CRP (often >50 mm/hr and higher when confirmed), abnormalities in the pupillary light reflex related to the optic nerve, and granulomatous inflammation and multinucleated giant cells observed on temporal artery biopsy (confirmatory). Ultrasound (halo sign), PET-CT/MRA/CTA can be used to assess large-vessel involvement.

Treatment

• Initial (urgent) principles: If decreased vision or threatened vision is suspected, administer high-dose steroids immediately when vasculitis is suspected. Steroids should be started first even if testing (biopsy or imaging) must be delayed.
• Drug treatment:
  • Threatened vision (such as acute visual loss): Intravenous methylprednisolone 500–1000 mg/day × 1–3 days, followed by a switch to oral prednisone (or prednisolone) (usually 1 mg/kg/day, maximum 60 mg/day).
  • When vision is not threatened: Start oral prednisone 40–60 mg/day (or 1 mg/kg/day), then gradually taper according to symptoms and inflammatory markers (over several months to several years).
  • Adjunctive treatment to reduce steroid use (in cases of steroid dependence or relapse): Consider subcutaneous tocilizumab (an IL-6 inhibitor) (e.g., 162 mg once weekly or every 2 weeks depending on the situation), methotrexate, and other immunosuppressants.
• Procedures/surgery: Complications caused by an aortic aneurysm or vascular stenosis (for example, when vascular reconstruction is required) should be evaluated by vascular surgery.
• Lifestyle management and prevention:
  • Management of steroid side effects (osteoporosis prevention: calcium and vitamin D, and bisphosphonates if needed; management of blood glucose, blood pressure, and weight; gastrointestinal protection (consider a PPI if there is a risk of gastric ulcer))
  • Check vaccination status (vaccination that can be given before steroids or immunosuppressants is recommended; exercise caution with live vaccines)
  • If acute worsening of vision occurs, immediately visit an emergency department or specialist
• Treatment duration and course: Taper over several months to several years according to improvement in symptoms and inflammatory markers; long-term follow-up is necessary because relapse is common.

Checklist Before an Outpatient Visit (Including Example Questions)

• Items/materials to prepare or provide:
  • Current medication list (including dosages) and allergies, past medical history (especially diabetes, osteoporosis, gastrointestinal ulcers, and history of infections)
  • When recent symptoms began and how they have progressed (timing and pattern of visual changes, jaw claudication, location and nature of headache, fever, weight loss, etc.)
  • Previous test results (ESR, CRP, CBC, liver and kidney tests, imaging results)
  • Results of vision tests (if possible, records of visual acuity and visual field tests)
  • Vaccination records (especially influenza, pneumococcal, and shingles vaccinations)
• Examples of questions to write down and prepare for the outpatient visit (for organizing the patient's own medical history):
  • "On what date did the symptoms first begin, and how have they changed?"
  • "Did your vision suddenly worsen? Was it in one eye or both, and was it constant or intermittent?"
  • "Are you currently taking any medications, especially anticoagulants or antidiabetic medications?"

Examples of General Questions to Ask the Doctor

• What are the expected side effects of this medication (steroid), and how can they be prevented?
• What is my prognosis? How high is the risk of blindness?
• What should I be careful about in my lifestyle (exercise, diet, vaccinations, etc.)?
• How are the need for and sequence of tests (biopsy and imaging) determined?
• How will the risks of osteoporosis and infection be managed during long-term steroid use?

Examples of Disease-Specific Questions

• In my case, what are the criteria for deciding whether immediate intravenous steroids (methylprednisolone) are needed or whether treatment can begin with oral medication?
• Which test should be performed first among temporal artery biopsy and ultrasound/PET-CT? If the biopsy is negative, what is the next step?