Giant Cell Arteritis

History Taking

Chief Complaint:

• New onset headaches, usually on one side of the head

• Jaw pain when chewing

• Visual disturbances or sudden vision loss in one eye

• Fever, fatigue, weight loss, and general discomfort

History of Presenting Complaint:

• Severe, localized headaches that started a few weeks or months ago

• The pain might worsen with scalp tenderness, brushing hair or wearing a hat

• Recent issues with vision, such as double vision or transient vision loss (amaurosis fugax)

• Experiencing pain in the tongue or throat, sometimes while eating

• Reports of generalized malaise or flu-like symptoms

System Review:

• Neurological: Visual disturbances, including partial or complete loss of vision, double vision

• Musculoskeletal: Polymyalgia rheumatica symptoms, such as aches, pain and stiffness in the shoulders, neck, or hips

• Cardiovascular: Potential claudication symptoms due to arteritis affecting other large arteries

Past Medical History:

• History of polymyalgia rheumatica, if present, can strongly indicate Giant cell arteritis

• Any auto-immune or vasculitis conditions

• Previous similar episodes with resolution

Drug History:

• Recent use of corticosteroids which may mask some symptoms

• Non-steroidal anti-inflammatory drugs (NSAIDs) for headache or musculoskeletal pain

Personal History:

• Typically, GCA occurs in individuals over 50 years of age

• Females are more likely to get it than males

• Northern European (particularly Scandinavian) ancestry is a risk factor

• High body mass index in early adulthood may be a risk factor

Social History:

• Smoking history: Some studies suggest an increased risk with smoking

• Alcohol: Moderate alcohol consumption may have a protective effect

Physical Examination

General Examination:

• Palpation of the temporal artery may reveal thickening, tenderness, and reduced pulsation

• Signs of weight loss or general ill health

Examination of the Hands and Arms:

• Absent or diminished pulses in the arm due to arteritis affecting the subclavian arteries

Examination of the Face:

• Evidence of ptosis or ophthalmoplegia due to cranial nerve involvement

• Fundoscopy may reveal pallor of the optic disc in case of anterior ischemic optic neuropathy, a complication of GCA

Examination of the Neck:

• Carotid arteries may show reduced pulsation if affected

Cardiac Examination:

• Bruits may be heard over the subclavian arteries or the carotid arteries if they are involved

• Some patients may exhibit signs of aortic regurgitation due to large vessel involvement

Neurological Examination:

• Visual field testing may reveal defects

• Check for signs of stroke or transient ischemic attacks due to involvement of cerebral arteries

Investigations

Laboratory Investigations:

• Full blood count: may show normocytic normochromic anemia or reactive thrombocytosis

• Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP): Both are markers of inflammation and are typically significantly elevated in GCA

• Liver function tests: Alkaline phosphatase can be elevated in case of large vessel GCA

• Autoimmune screen: to rule out other vasculitis or connective tissue diseases

Imaging:

• Ultrasound of the temporal and axillary arteries: to identify a 'halo sign' which is an echo-poor area around the temporal artery

• MRI, CT, or PET scan: may be needed to identify large vessel involvement

Invasive:

• Temporal artery biopsy: the gold standard for diagnosis, showing characteristic granulomatous inflammation with multinucleated giant cells, although it can be negative in up to 15% of cases

• Angiography: can be useful to confirm involvement of large arteries such as the aorta or subclavian arteries

Other Tests:

• Visual field testing: to identify any defects due to optic nerve ischemia

• Ophthalmoscopy: to identify signs of retinal or optic nerve ischemia

Management

General Management:

• Patient education: Explanation about the condition, its implications, the need for urgent treatment and long-term follow-up

Medical:

• High-dose corticosteroids: Immediate treatment with oral prednisolone or intravenous methylprednisolone to prevent vision loss

• Steroid-sparing agents: Methotrexate or azathioprine can be used for patients who have recurrent or refractory disease or those who experience significant side effects from corticosteroids

• Antiplatelet or anticoagulant therapy: Low-dose aspirin may be recommended to reduce the risk of stroke

Surgical:

• Temporal artery biopsy: Invasive but can confirm diagnosis and may be performed after starting corticosteroid therapy

• Rarely, vascular surgery may be required in cases with significant large vessel involvement

Other:

• Regular follow-up: Monitoring for disease activity, side effects of treatment, and development of associated conditions (like polymyalgia rheumatica)

• Bone protection: Patients on long-term corticosteroids should be offered bone protection, such as bisphosphonates and calcium/vitamin D supplements

• Vaccinations: Annual influenza and regular pneumococcal vaccines due to increased susceptibility from long-term corticosteroid use

• Lifestyle modifications: Encourage smoking cessation and healthy diet, as patients are at increased risk of cardiovascular disease.