View source for WBR0429

 {{WBRQuestion
|QuestionAuthor= {{YD}} (Reviewed by  {{YD}} and  {{AJL}})
|ExamType=USMLE Step 1
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|SubCategory=Vascular
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=Vascular
|Prompt=A 78-year-old woman presents to the physician’s office with complaints of right-sided headache, low-grade fever, and fatigue for the past 4 days. She states that she has a history of tension-type headaches, but her current headache is not the same and has not been relieved by either NSAIDs or acetaminophen. Her past medical history is remarkable for chronic, bilateral pain and stiffness in her proximal muscles. Upon further questioning, the patient explains that she has recently been experiencing pain in her jaw every time she chews her food. Her temperature is 38.2 °C (100.8 °F), heart rate is 104/min, and blood pressure is 122/86 mmHg. Physical examination is remarkable for scalp tenderness on the right side. Work-up is remarkable for Hb= 11.2 g/dL, MCV=88 fL, WBC=10,800 cells/mm3, and erythrocyte sedimentation rate (ESR)=122 mm/hr. The administration of high-dose steroids is most essential to prevent which of the following complications?
|Explanation=Giant cell (temporal) arteritis (GCA) is a [[large-vessel vasculitis]] that frequently affects the elderly. It is characterized by focal granulomatous inflammation that commonly affects branches of the carotid artery. GCA typically manifests with fatigue, [[low-grade fever]], unilateral [[headache]], and [[jaw claudication]]. Physical examination is typically remarkable for scalp tenderness. Classically, patients may also have a nodular temporal artery with decreased or absent pulsations. Weight loss and anorexia may also be present in the minority of cases. GCA is often associated with [[polymyalgia rheumatica]], which is characterized by bilateral pain and stiffness in the proximal muscle groups with no motor weakness. Lab findings in GCA are non-specific and often includes markedly elevated ESR, mild normocytic normochromic anemia, mild elevation in WBC, and mild elevation in ALP. [[Temporal artery biopsy]] is the gold standard for the diagnosis of GCA and usually demonstrates discontinuous areas of [[granulomatous]] inflammation (skip lesions) that penetrate all layers of the artery wall and stain positively for inflammatory markers, such as [[leukocyte common antigen]] ([[LCA]]) and [[CD15]]. Blindness is the most important complication of GCA, which may be present in up to 15% of patients. Blindness among patients with GCA is not always preceded by ophthalmologic symptoms or signs on physical examination. Accordingly, GCA requires prompt medical attention and use of high-dose prednisone is indicated to the prevention of blindness. Administration of steroids is often met with remarkably rapid improvement in symptoms within 1 to 3 days, but high dose steroid therapy is usually continued until ESR drops to normal values (usually 4 to 6 weeks), after which steroid therapy is tapered to a maintenance low-dose for approximately 2 years.
|AnswerA=Hearing loss
|AnswerAExp=Hearing loss is not classically associated with GCA.
|AnswerB=Auto-amputation of digits
|AnswerBExp=Auto-amputation of digits is a classical complication of [[thromboangiitis obliterans]].
|AnswerC=Blindness
|AnswerCExp=Blindness is a classical complication of GCA.
|AnswerD=Glomerulonephritis
|AnswerDExp=[[Glomerulonephritis]] classically occurs secondary to granulomatosis with polyangiitis ([[Wegener granulomatosis]]) or [[Goodpasture syndrome]]. It is not a classical complication of GCA.
|AnswerE=Coronary aneurysm
|AnswerEExp=Coronary aneurysms are classical complications of [[Kawasaki disease]], a medium-vessel vasculitis.
|EducationalObjectives=Giant cell (temporal) arteritis (GCA) is a [[large-vessel vasculitis]] that frequently affects the elderly. It typically manifests with fatigue, [[low-grade fever]], unilateral [[headache]], and [[jaw claudication]]. Physical examination is typically remarkable for scalp tenderness. Classically, patients may also have a nodular temporal artery with decreased or absent pulsations. GCA is often associated with [[polymyalgia rheumatica]], which is characterized by bilateral pain and stiffness in the proximal muscle groups with no motor weakness. Blindness is the most important complication of GCA, which may or may not be preceded by ophthalmologic signs or symptoms.
|References=Desmet GD, Knockaert DC, Bobbaers J. Temporal arteritis: the silent presentation and delay in diagnosis.  Journal of Internal Medicine. 2009;227(4):237-240.<br>
Meskimen S, Cook TD, Blake RL, et al. Management of giant cell arteritis and polymyalgia rheumatica. Am Fam Physician. 2000;61(&):2061-8.<br>
First Aid 2014 page 296.
|RightAnswer=C
|WBRKeyword=Temporal arteritis, Giant cell arteritis, Blindness, Vision loss, Steroids, Prednisone, Corticosteroids, Complication, Headache, Jaw claudication, Scalp tenderness, ESR
|Approved=Yes
}}