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Giant Cell Arteritis (GCA) Mark Stradling, OMS IV Introduction Introduction • Also know as temporal arteritis, cranial arteritis, and granulomatous arteritis. • Systemic inflammatory vasculitis of unknown etiology. • Affects medium- and large-sized arteries. • Disease of the elderly population. Introduction • Results in systemic, neurologic, and ophthalmologic complications. • Visual loss is the most significant cause of morbidity. • Permanent visual impairment may occur in up to 60% of patients with GCA. • True neuro-ophthalmic emergency. Pathophysiology Pathophysiology • Typically involves inflammation of the aortic arch and its branches. • Almost any artery, as well as veins, may be affected occasionally. • Likely determinant of arterial susceptibility to GCA is the presence and/or quantity of internal elastic lamina within the vessel wall. Pathophysiology • Most commonly involved arteries: – – – – Extracranial vertebral arteries Superficial temporal arteries Posterior ciliary arteries Opthalmic arteries Pathophysiology • Other commonly affected arteries: – – – – – – – – Internal carotid External carotid Central retinal arteries Proximal aorta Distal aorta Subclavian arteries Brachial arteries Abdominal arteries Histopathology • Reveals inflammatory infiltrate surrounding a fragmented internal elastic lamina within the media of an arterial wall. • Infiltrate consists predominantly of mononuclear cells with giant cell formation. • Mechanism is believed to be related to dysfunction of cellular immunity, but etiology is unknown. Frequency • Approximately 0.5-27 cases per 100,00 people aged 50 years or older. • Annual incidence is higher in northern areas of the US. Mortality / Morbidity Mortality / Morbidity • In the milder form, patients may complain of only generalized muscle aches and pains, and unusual fatigue. • Intermittent claudication occurs in about 50% of patients. • In small percentage of patients, claudication of the tongue or throat develops with eating and repeated swallowing. Mortality / Morbidity • Visual symptoms are present in about 33% of patients. – 40-50% are transient – 50-60% are permanent • One of the more serious complication is the onset of blindness from involvement of the ophthalmic artery. Mortality / Morbidity • Permanent visual loss may be partial or complete and may occur without warning – 50% are unilateral – 50% are bilateral • Varied visual symptoms including blurring of vision, diplopia, and loss of vision occur in 36-60% of patients. Mortality / Morbidity • Involvement of major vessels (Aorta) predisposes patients to higher risks for death. • In Evans and colleagues’ report, 50% of those with thoracic aorta aneuryms died suddenly from aortic dissection. [Evans JM, Hunder GG: Polymyalgia and giant cell arteritis. Clin Geriatr Med 1998 Aug; 14(3): 455-73] Mortality / Morbidity • Race – incidence rates appear to be high in Caucasians or European descent. This condition is less commonin African Americans and Asians • Sex: women are 2-4 times more likely to have GCA than men. • Age: mostly occurs in patients > age 50 – peaks at the eighth decade; Rare in patients younger than 50 years of age. Clinical Overview General History • Onset of GCA may be abrupt or insidious. • Usually symptoms have been present for weeks or months before the diagnosis is established. • Constitutional symptoms including anorexia, fatigue, and weight loss are present in most patients and may be an initial finding. Ophthalmic History • 50% of patients with GCA eventually experience visual symptoms (transient visual blurring, diplopia, eye pain, sudden loss of vision). • Transient repeated episodes are usually reversible. • Sudden loss of vision is ominous and almost always permanent. Ophthalmic History • The most common cause of vision loss is anterior ischemic optic neuropathy (AION). • Results from ischemia of the optic nerve head, supplied mainly by the posterior ciliary arteries. • Most AION is nonarteritic (87-91%). • History of sudden painless loss of vision frequently accompanies the patient with AION. Systemic History • May begin with symptoms of anorexia, fever, malaise, myalgia, night sweats, and weight loss. • Prodromal symptoms may occur for a few days or may even stretch out to weeks. • Hallmark symptom of GCA is its new-onset localized headache. • Localized to the temporal or occipital area, and may be occasionally may be diffuse or bilateral. Ophthalmic Exam • Most common cause of vision loss is AION. • Examination of the fundus may reveal optic disc edema, with or without splinter hemorrhages along the disc margin. • Arteritic AION, as in GCA, typically presents with a chalky white edematous optic disc. • Automated visual field testing reveals an inferior altitudinal defect, inferior nasal sectorial defect, or central scotoma. Ophthalmic Exam • Other presentations include: – – – – Posterior ischemic optic neuropathy Central retinal artery occlusion Branch retinal artery occlusion Choroidal ischemia Ophthalmic Exam • Neuro-ophthalmic manifestations include: – – – – – Diplopia Ptosis Nystagmus Internuclear ophthalmoplegia Pupillary abnormalities Systemic Exam • Hallmark symptom is new-onset localized headache – Temporal area – Occipital area – Diffuse or bilateral Systemic Exam • Of interest is the scalp tenderness that accompanies this headache – especially over the temporal region • Tenderness often induced by very gentle pressure. • Hypersensitivity or hyperesthesia, ie when gently stroking the patient’s hair, results in a characteristic complaint of pain – this is anecdotally described as the single most important clinical finding for GCA. Systemic Exam • Other clinical features include: – Pulselessness and/or tenderness and inflammation along the course of the temporal artery and bruits in the cranial or neck area – Jaw claudication – Atrophy of temporal and tongue muscles – Temporal artery blood flow measurements may reduced Systemic Exam • Cerebrovascular disease occurs in 1-25% of patients and is believed to be the most common cause of death in patients with GCA. • Neurologic problems associated with GCA include myopathy, neuro-otologic syndromes, neuropsychiatric syndromes, peripheral neuropathies, and seizures. Systemic Exam • Cardiovascular, pulmonary, gastrointestinal, renal, and dermatologic manifestation also may occur. Causes Causes • Overall, etiology is unknown. • Genetic – persons of northern European decent. • Infectious – Chlamydia and parvovirus may be impetus for destructive inflammation. Causes • Autoimmune – (cellular and humoral). The granulomatous histopathology of GCA has suggested the presence of a cell-mediated immune reaction directed at antigens in or near elastic tissue in the arterial walls. Differentials • • • • • • • • Polymyalgia rheumatica Transient ischemic attack Systemic infections Amyloidosis with prominent vascular involvement Neoplasms Arteriosclerotic vascular disease Arteriovenous fistulas Other forms of vasculitis Lab Studies Lab Studies • Erythrocyte sedimentation rate (ESR) (moderate to > 100 mm/h) is common and is rarely (~ 3%) normal. Highly elevated ESR results are characteristic of a GCA process. • C-reactive protein (CRP) – elevated and reflects the underlying inflammatory process. May assist in monitoring for treatment dosing and response. Lab Studies • Fibrinogen –increased along with other acute phase reactants. • Most patients are mildly anemic (normochromic, normocytic) during the active phases. Platelet counts often are increased. • Hepatic enzymes (alkaline phosphatase and serum aspartate aminotransferase [SGOT]) are elevated in 20-30% of cases. • Prolonged prothrombin time also may be found. Imaging Studies Imaging Studies • Aortic arch and cerebral angiography may show occlusion or alternating stenotic areas. • Arteriography is sensitive, but nonspecific and is deemed unreliable diagnostically. • CT and MRI imaging of the brain are not first-line diagnostic procedures for GCA. Other Tests • Automated visual field typically reveals an inferior altitudinal defect, inferior nasal sectorial defect, or central scotoma. Procedures • Superficial temporal artery biopsy (TAB) shows focal granulomatous arteritis, often with giant cells with skip areas within normal arterial walls. Histologic Findings Histologic Findings • Early cases: – Collections of lymphocytes are confined to the region of the internal or external elastic lamina or adventitia in early cases or regions show arteries with minimal involvement. – Intimal thickening, with prominent cellular infiltration, is typically present. Histologic Findings • Late cases: – All layers are affected in late cases or regions of arteries with marked involvement. – Widespread areas of necrosis of portions of the arterial wall. – Elastic laminae usually involved. – Some plasma cells and fibroblasts are usually present. Treatment Medical Care • The universally accepted treatment for GCA is high-dose corticosteroid therapy. • Goals of treatment are to reverse the disease and to prevent further progression. This is of utmost importance especially in the ophthalmic arteries to prevent blindness. Medical Care • Using constitutional symptoms, vascular symptoms, and the ESR findings as guides, physicians usually are able to gradually taper steroids to a maintenance dose for 2 years. • Initially, high doses of corticosteroids may be given at 1-2 mg/kg/day until the disease activity is suppressed adequately. Medical Care • Once the signs of clinical inflammation are suppressed and the ESR is maintained at a low level, corticosteroids may be tapered slowly. • No agreement exists as the length of treatment with corticosteroids for GCA. • It may be reasonable to maintain the patient on treatment for 2 years to lessen the chances for relapses, although relapses have been reported. Surgical Care • Aside from the performance of a superficial TAB, usually no further surgical intervention is necessary in the management of patients with GCA. Consultations • Rheumatologist – Indicated when initiating high-dose steroid therapy for presumed GSA. – Indicated to consider other forms of immunosuppressive therapy in those patients who do not respond adequately to steroid therapy. Follow-up Further Inpatient Care • Monitor the patient’s symptoms and the subjective and objective visual acuity on a daily basis. Further Outpatient Care • Since this is a potentially blinding and lethal disease, regular follow-up care after a successful initial management of an acute process is considered a standard of care. In/Out Patient Medications • Corticosteroids are the mainstay of therapy. In some steroid-resistant cases, a recipe of cyclosporin-azathioprine or cyclosporinmethotrexate may be used. Complications • Reported vascular complications include stroke, aortic artery aneurysms, myocardial infarction, and visceral organ ischemia. • The complications associated with late disease are rare, but attempts to discontinue therapy often cause relapses. Prognosis • GCA is a chronic disease that may last for years. Although the overall course of the disease is one of progressive improvement, and eventual complete resolution, the clinical course is highly variable, and, in some patients, it may be protracted for months to years. Patient Education • Instruct patients to immediately consult a physician when they experience symptoms of transient blurring of vision because of the possibility of impending attacks of GCA. • Discuss the adverse effects of corticosteroid therapy so that patients will use prednisone carefully and as instructed. Competency Exam Question One The following arteries are most commonly involved in GCA, except: A) Extracranial vertebral arteries B) Posterior ciliary arteries C) Ophthalmic arteries D) Intracranial arteries E) Superficial temporal arteries Question One The following arteries are most commonly involved in GCA, except: A) Extracranial vertebral arteries B) Posterior ciliary arteries C) Ophthalmic arteries D) Intracranial arteries E) Superficial temporal arteries Question Two True or False: Giant Cell Arteritis mostly affects those from the African-American and Asia descent. Question Two True or False: Giant Cell Arteritis mostly affects those from the African-American and Asia descent. Question Three What is the universally accepted treatment for Giant Cell Arteritis: A) Azathioprine B) Cyclophosphamide C) High-dose corticosteroids D) Dapsone E) Methotrexate Question Three What is the universally accepted treatment for Giant Cell Arteritis: A) Azathioprine B) Cyclophosphamide C) High-dose corticosteroids D) Dapsone E) Methotrexate End of Lecture Questions?