Giant Cell Arteritis (Temporal Arteritis)

• Giant cell arteritis, historically referred to as temporal arteritis, is an inflammation of medium- and large-sized arteries. Involves one or more branches of the carotid artery, particularly the temporal artery. It is a systemic disease that can involve arteries in multiple locations, particularly the aorta and its main branches. Systemic vasculitis of multiple medium and large-sized arteries, which may go undetected.
• Closely associated with polymyalgia rheumatica, which is characterized by stiffness, aching, and pain in the muscles of the neck, shoulders, lower back, hips, and thighs. Polymyalgia rheumatica may be seen in 40–50% of patients with giant cell arteritis. Pathophysiologic studies suggest that giant cell arteritis and polymyalgia rheumatica represent different clinical spectrums of a single disease process.
• Age > 50yrs, Females > males. Rare in blacks. High in Scandinavians.
• Association with HLA-DR4
• Histopathologically, the disease is a panarteritis with inflammatory mononuclear cell infiltrates within the vessel wall with frequent giant cell formation.
• It is an antigendriven disease in which activated T lymphocytes, macrophages, and dendritic cells play a critical role
• Two separate lineages of CD4 T cells–-IFN-γ-producing TH1 cells and IL-17-producing TH17 cells—participate in vascular inflammation and may have differing levels of responsiveness to glucocorticoids.
• Symptoms: complex of fever, anemia, high ESR, and headaches. Other phenotypic manifestations include features of systemic inflammation including malaise, fatigue, anorexia, weight loss, sweats, arthralgias, polymyalgia rheumatica, or large vessel disease. With cranial arteries involvement, headache is associated with a tender, thickened, or nodular artery, which may pulsate early in the disease but may become occluded later. Scalp pain and claudication of the jaw.
• A well-recognized and dreaded complication of giant cell arteritis, particularly in untreated patients, is ischemic optic neuropathy, which may lead to serious visual symptoms, even sudden blindness in some patients. Other cranial ischemic complications include strokes and scalp or tongue infarction
• large-vessel disease can include subclavian artery stenosis that can present as arm claudication or aortic aneurysms involving the thoracic and to a lesser degree the abdominal aorta, which carry risks of rupture or dissection
• Lab findings: High ESR, abnormal LFT (ALP+). CK is normal.
• Diagnosis: Temporal artery biopsy and ultrasound. A dramatic clinical response to a trial of glucocorticoid therapy can further support the diagnosis.
• Treatment should begin with prednisone, 40–60 mg/d for 1 month, followed by a gradual tapering. With ocular signs use methylprednisolone 1 gm daily for 3 initial days. Duration of steroid treatment - approx 2 yrs. Aspirin for vascular complications.

Polymyalgia rheumatica

Polymyalgia rheumatica is a clinical diagnosis made by the presence of typical symptoms of stiffness, aching, and pain in the muscles of the hip and shoulder girdle, an increased ESR, the absence of clinical features suggestive of giant cell arteritis, and a prompt therapeutic response to low-dose prednisone (10-20 mg/d).