Name
GIANT CELL ARTERITIS
DESCRIPTION
DETAIL
CAUSES β’ Etiology unknown β’ Possibly immunologic mechanism -------------------------------------------------------------------------- DIFFERENTIAL DIAGNOSIS β’ Cerebral vasculitides β’ Other causes of headache (tumor, sinusitis, cervical or temporomandibular joint arthritis) β’ Cerebral vascular insufficiency β’ Other connective tissue disease β’ Retinal detachment or other causes of loss of vision β’ Septic arteritis β’ Embolic diseaseβ’ ESR (Westergren) usually greater than 50 (may be over 100) β’ ESR may be normal in < 10% of patients β’ Elevated alkaline phosphatase over 1.5 x normal (unusual) β’ Elevated aspartate aminotransferase (AST) over 1.5 x normal (unusual) β’ Anemia - mild to moderate, normochromic/normocytic β’ Mild leukocytosis β’ Mild thrombocytosis SPECIAL TESTS Temporal artery biopsy - need serial section in specimen of adequate size (at least 1 inch). Bilateral biopsy may be necessary. IMAGING : Temporal arteriography (in selected cases) DIAGNOSTIC PROCEDURES : . Temporal artery biopsy . Minimum 2.5 cm segment of vessel with serial sections . Within 96 hours of starting steroids . If negative, must consider biopsy of contralateral artery (may increase yield up to 10-14%)
TYPENOTES
RISK FACTORS : Age over 50, Presence of polymyalgia rheumaticaAPPROPRIATE HEALTH CARE β’ Outpatient surgery (initially for temporal artery biopsy) β’ With reasonable suspicion, immediately institute high dose corticosteroid therapy while arranging temporal artery biopsy GENERAL MEASURES : Institute surveillance for corticosteroid side effects, including osteoporosis screening SURGICAL MEASURES : β’ Temporal artery biopsy DIET β’ Appropriate salt restriction β’ Adequate calcium intake (1500 mg/day) β’ Watch serum glucose PATIENT EDUCATION β’ Precautions regarding steroid use, especially osteoporosis β’ Exacerbation of disease with medication dose adjustment β’ Adrenal suppression - patients should get medical alert bracelet or neck tag β’ With CNS symptoms or headache, call physician immediately for adjustment of steroid dose DRUG(S) OF CHOICE . Prednisone - early: . 60 mg prednisone/d; single morning dose (never use every other day steroids) . Begin slow taper after 6-8 weeks if asymptomatic and ESR decreased (occasionally patient may not normalize ESR) . Prednisone - taper: . Taper initially by 5 mg every 2 weeks to dose of 25 mg. Then slow taper by 2.5 mg decrements every 2-4 weeks to a dose of 10-15 mg if above guidelines are met. (Must be individualized). . Continue 10-15 mg daily for several months-year, with periodic attempts to taper (i.e., every 3-6 months) by 1 or 2 mg . Use symptoms and ESR to help guide taper . Average time to disease remission 3-4 years, range 1-10 years ALTERNATIVE DRUGS Methotrexate only if patient cannot use steroids (brittle diabetes mellitus, severe osteoporosis, congestive heart failure, etc.) or fails to respond to steroids PATIENT MONITORING β’ ESR - repeat at monthly intervals initially and while tapering, then every 3 months β’ Follow visual/constitutional symptoms monthly initially, then as needed POSSIBLE COMPLICATIONS β’ Complications related to steroids β’ Exacerbation of disease during therapy or taper β’ Blindness, stroke EXPECTED COURSE/PROGNOSIS β’ With early treatment, resolution of symptoms and preservation of vision β’ Average length of disease 3-4 years β’ With no treatment, high risks of blindness and stroke β’ Occasionally ESR elevation not related to GCA activity and cannot be used to monitor and/or adjust treatment
RELATED DISEASE
Not Available Disease
DISEASE
INVESTIGATION
SGPT ( ALT ), SERUM ALKALINE PHOSPHATASE, COMPLETE BLOOD COUNT, BIOPSY