A 77-year-old woman is generally healthy, but over the past

[kailash]

A 77-year-old woman comes to the emergency department because of a "real bad left-sided headache." She says that she is generally healthy, but over the past few weeks she has experienced fever, fatigue, transient visual loss in the left eye, and scalp pain. Her temperature is 38.2 C (100.8 F), blood pressure is 130/90 mm Hg, pulse is 68/min, and respirations are 18/min. Physical examination shows tenderness over the right temple. The remainder of the examination is unremarkable. The most appropriate next step is to

A. determine the erythrocyte sedimentation rate
B. determine Hepatitis B serology
C. obtain a surgery consult for a renal biopsy
D. obtain a surgery consult for a temporal artery biopsy
E. order a CT scan of the head
F. order an MRI of the head
G. start immediate treatment with methylprednisolone, intravenously

[kailash]

The answer is G. This patient most likely has temporal arteritis (TA), and requires immediate treatment to prevent blindness. TA often affects elderly women and presents with fever, anemia, an elevated erythrocyte sedimentation rate, and a headache. A biopsy typically shows panarteritis with inflammatory mononuclear cell infiltrates and giant cells within the wall of the temporal artery. A segmental biopsy is often necessary to establish the diagnosis, because the disease may be segmental. Serious complications are ocular involvement and blindness, which may be avoided with early corticosteroid therapy. If temporal arteritis is suspected, corticosteroids should be given immediately, even before the biopsy is performed, to prevent blindness. Temporal arteritis is often associated with polymyalgia rheumatica, which is characterized by stiffness, aching, and pain in large muscle groups.

The erythrocyte sedimentation rate (choice A) is often elevated in patients with temporal arteritis (TA), however, this patient has had transient visual loss, which may progress to permanent blindness, and requires immediate treatment even before the diagnosis is established. The work-up can be done after treatment is initiated.

Hepatitis B serology (choice B) is part of the diagnostic evaluation of patients with polyarteritis nodosa (PAN), not temporal arteritis. Patients with polyarteritis nodosa, which is a multi-system necrotizing vasculitis, often have a positive test for hepatitis B surface antigen. These patients often present with fever, weight loss, malaise, and other symptoms that are specific to the involved organs. These patients may have positive p-ANCA titers. A tender temporal artery and transient visual loss are not typically found in polyarteritis nodosa.

A renal biopsy (choice C) is sometimes used to establish the diagnosis of polyarteritis nodosa (PAN), not temporal arteritis. PAN is a multi-system necrotizing vasculitis that often involves the renal arteries. Hypertension is present when the renal arteries are affected. The typical renal finding is arteritis without glomerulonephritis. Treatment is prednisone and cyclophosphamide.

A temporal artery biopsy (choice D) is performed to establish the diagnosis of temporal arteritis. This patient has symptoms that are consistent with this disease and therefore treatment must be started immediately to prevent blindness. A biopsy should be obtained after the corticosteroids are given.

A CT scan (choice E) and an MRI of the head (choice F) are not part of the work-up for temporal arteritis. Temporal arteritis is an inflammatory disorder of medium and large-sized arteries that typically involves the branches of the carotid artery. The diagnosis is confirmed with a temporal artery biopsy. If a tumor, a hemorrhage, cerebrovascular accident, or a transient ischemic attack are suspected, these tests should be considered.