What are the potential complications and treatment options for giant cell arteritis?

Complications of Giant Cell Arteritis

Blindness is a major complication of giant cell arteritis (GCA), occurring in 14-35% of untreated patients, and is often permanent once it develops. 1, 2

Major Complications of GCA

Visual Complications

• Permanent vision loss: Occurs in 14-35% of untreated patients 1, 2
  • Usually develops before initiation of glucocorticoid therapy
  • Risk of losing second eye is as high as 50% if one eye is affected 1
  • Typically caused by arteritic anterior ischemic optic neuropathy (AAION) 3
  • Rarely can present as ocular ischemic syndrome 3

Neurological Complications

• Stroke: A rare but serious ischemic complication 1
• Cranial nerve palsy: Can affect oculomotor and other cranial nerves 1, 3
• Hemiparesis: Can occur due to cerebrovascular involvement 1

Vascular Complications

• Large-vessel aneurysms: Can develop in aorta and major branches 1
• Vascular stenosis: Leading to limb claudication and absent pulses 1
• Scalp necrosis: A rare but serious complication 1
• Tongue necrosis: Due to compromised blood supply 1
• Peripheral limb ischemia: From involvement of peripheral arteries 1

Other Complications

• Systemic manifestations:
  • Polymyalgia rheumatica symptoms (in approximately 50% of patients) 2
  • Constitutional symptoms (fever, fatigue, weight loss) 1
  • Jaw claudication 2

Uveitis and Arthritis in GCA

Notably, uveitis and arthritis are not typically listed as common complications of GCA in the major guidelines reviewed. The primary ocular complication is vision loss due to ischemic optic neuropathy rather than uveitis 1, 2, 3. While patients with GCA may experience joint pain, this is more commonly associated with concurrent polymyalgia rheumatica rather than true inflammatory arthritis 2.

Prevention of Complications

Immediate Treatment

• Emergency glucocorticoid therapy: Must be initiated immediately upon suspicion of GCA 2
  • Oral prednisone 40-60 mg/day for typical cases
  • IV methylprednisolone 500-1000 mg/day for cases with visual symptoms
  • Treatment should not be delayed while awaiting biopsy results

Advanced Treatment Options

• Tocilizumab: FDA-approved for GCA, reduces glucocorticoid requirements and flare rates 1, 4
  • Administered as 162 mg subcutaneously weekly 2
  • Has demonstrated efficacy in reducing GC requirements and flare rates 1

Monitoring and Follow-up

• Regular assessment of symptoms, physical examination, and inflammatory markers (ESR, CRP) 2
• Vascular imaging to evaluate large vessel involvement and disease progression 2
• Vigilance for steroid-related adverse effects 2

Clinical Pearls

• Vision loss almost exclusively occurs before initiation of glucocorticoid therapy 1
• Fast-track GCA clinics have improved outcomes by facilitating rapid diagnosis and treatment 1, 5
• Despite appropriate treatment, some patients may still develop visual complications up to 3 weeks after starting steroids 6
• Flares occur in 34-62% of patients, and only 15-20% achieve sustained remission with glucocorticoids alone 1

Understanding these complications and implementing prompt treatment is critical to preventing irreversible damage and improving outcomes in patients with GCA.