View source for Giant cell arteritis

''The term "temporal arteritis" is no longer used.  It refers to giant cell arteritis that affects the temporal artery.''

==Background==
[[File:Histopathology of giant cell arteritis.png|thumb|Giant cell arteritis on histopathology.]]
[[File:Gray508.png|thumb|The arteries of the face and scalp.]]
*Systemic [[vasculitis]] most commonly involving medium-sized arteries in the carotid circulation, affecting 1% of the population<ref>Gonzalez-Gay, MA et al. Epidemiology of the vasculitides. Rheum Dis Clin North Am. 2001;27:729-749</ref>
**Temporal artery is the most commonly involved, but ophthalmic, occipital, and other arteries off the aorta can also be involved
**Most frequent primary large-vessel vasculitis in patients over 50<ref>Régent A, Mouthon L. Treatment of Giant Cell Arteritis (GCA). J Clin Med. 2022 Mar 24;11(7):1799. doi: 10.3390/jcm11071799. PMID: 35407411; PMCID: PMC8999932.</ref>
**Elevated risk in women and Northern European descent
*Giant cell arteritis, with possible involvement of large vessels like aorta leading to<ref>Morabito GC, Tartaglino B. Chapter 279. Emergencies in Systemic Rheumatic Diseases. In:  JE, Stapczynski JS, Cline DM, Ma OJ, Cydulka RK, Meckler GD, eds. 's Emergency Medicine: A Comprehensive Study Guide. 7th ed. New York: McGraw-Hil</ref>:
**[[Temporal arteritis]]
**[[Aortic regurgitation]]
**Aortic arch syndrome
**[[Aortic dissection]]
*"Rule of 50s" can help remember useful points - "temporal arteritis affects patients at least 50 years of age, with a serum ESR > 50 mm/hr and is treated with 50mg of [[prednisone]] daily"
*Can cause painless, ischemic optic neuropathy with severe vision loss if left untreated
*Associated with [[polymyalgia rheumatica]] <ref> Lehrmann JF, Sercombe CT: Systemic Lupus Erythmatosus and the Vasculitides, in Marx JA, Hockberger RS, Walls RM, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 7. St. Louis, Mosby, Inc., 2010, (Ch) 116: p 1497-1510.</ref>
**50% of patients with Giant Cell Arteritis have concomitant Polymylalgia Rheumatica. 15% of patients with Polymyalgia Rheumatica develop Giant Cell Arteritis

{{Primary Vasculitis DDX}}

==Clinical Features==
*[[Fever]] or other constitutional symptoms
*[[Headache]] in 85%
**Gradually worsens over days, worse at night
**Usually unilateral near temple/periorbital area, but can be nonfocal
**May have tender scalp on palpation
*Jaw claudication
*[[Myalgia]] ([[polymyalgia rheumatica]])
*[[Visual loss]] in one eye in 50%
**Posterior ciliary artery
**May present as amaurosis fugax, transient diplopia, or complete blindness
**Second eye may be affected within weeks after first
*Tender, pulseless temporal artery
*Afferent pupillary defect
*Pale and edematous optic disc

===Likelihood Ratio of Findings===
''Jaw claudication and a beaded temporal artery increase the likelihood of temporal arteritis the greatest''<ref>Smetana GW, et al. Does this patient have temporal arteritis? JAMA. 2002;287:92-101</ref>
{| {{table}}
| align="center" style="background:#f0f0f0;"|'''Finding'''
| align="center" style="background:#f0f0f0;"|'''(+) Likelihood Ratio of Temporal Ateritis'''
| align="center" style="background:#f0f0f0;"|'''Negative Likelihood Ratio'''
|-
| Jaw claudication||4.2 (2.8-6.2)||0.72 (0.65 - 0.81)
|-
| Diplopia||3.4 (1.3-8.6)||0.95 (0.91 - 0.99)
|-
| Temporal artery beading||4.6 (1.1 - 18.4)||0.93 (0.88-0.99)
|-
| Enlarged temporal artery||4.3 (2.1-8.9)||0.67 (0.5-0.89)
|-
| Painful temporal artery||2.6 (1.9-3.7)||0.82 (0.74-0.92)
|-
| Absent temporal artery pulse||2.7 (0.55 - 13.4)||0.71 (0.38 - 1.3)
|-
| Abnormal ESR||1.1 (1.0-1.2)||0.2 (0.08 - 0.51)
|}

==Differential Diagnosis==
{{Headache DDX}}
{{Acute vision loss noninflamed DDX}}

==Evaluation==
*ESR ~70-110
**84% sensitivity, 30% specificity<ref>Kermani TA, et al. Utility of erythrocyte sedimentation rate and C-reactive protein for the diagnosis of giant cell arteritis. Semin Arthritis Rheum. 2012; 41:866–871.</ref>
**>15% of patients can have a normal ESR
*CRP elevated<ref>Kermani et al. Utility of Erythrocyte Sedimentation Rate and C-Reactive Protein for the Diagnosis of Giant Cell Arteritis. Semin Arthritis Rheum. 2012 Jun; 41(6): 866–871.</ref>
**More sensitive than ESR
**Doesn't have normal age related increase like ESR does
*The role of ESR/CRP is more to rule out (if both normal) rather than to confirm the diagnosis when they are elevated. 4% of patients have normal CRP and ESR with biopsy confirmed diagnosis<ref>Jhun P, et al. Giant Cell Arteritis: Read the Fine Print!  Ann Em Med. 2015; 65(5):615–617.</ref>

*Ultrasound<ref>Hernández P, Al Jalbout N, Matza M, Kohler MJ, Shokoohi H. Temporal Artery Ultrasound for the Diagnosis of Giant Cell Arteritis in the Emergency Department. Cureus. 2023 Jul 24;15(7):e42350. doi: 10.7759/cureus.42350. PMID: 37621789; PMCID: PMC10445179.</ref>
**Increasingly used as a first-line investigation due to availability/speed and ability to capture larger segments of the artery
**May show a noncompressible involved artery with hypoechoic wall thickening<ref>Wolfgang A Schmidt, Ultrasound in the diagnosis and management of giant cell arteritis, Rheumatology, Volume 57, Issue suppl_2, February 2018, Pages ii22–ii31, https://doi.org/10.1093/rheumatology/kex461</ref>

===American College of Rheumatology Criteria<ref>Hunder GG. The American College of Rheumatology 1990 criteria for the classification of giant cell arteritis.   Arthritis Rheum.  1990; 33(8):1122-8 </ref>===
*3 or more criteria 93% sensitive and 91% specific
**Age ≥ 50 years old
**New onset of headache
**Temporal artery tenderness or DECREASED temporal pulse (not related to carotid disease)
**ESR ≥ 50 mm/hr
**Artery biopsy with necrotizing arteritis or a granulomatous process with multinucleated giant cells

==Management==
*[[Methylprednisolone]] 500-1000mg IV QD x3d as a pulse dose <ref>Maz M, Chung SA, Abril A, Langford CA, Gorelik M, Guyatt G, Archer AM, Conn DL, Full KA, Grayson PC, Ibarra MF, Imundo LF, Kim S, Merkel PA, Rhee RL, Seo P, Stone JH, Sule S, Sundel RP, Vitobaldi OI, Warner A, Byram K, Dua AB, Husainat N, James KE, Kalot MA, Lin YC, Springer JM, Turgunbaev M, Villa-Forte A, Turner AS, Mustafa RA. 2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Giant Cell Arteritis and Takayasu Arteritis. Arthritis Rheumatol. 2021 Aug;73(8):1349-1365. doi: 10.1002/art.41774. Epub 2021 Jul 8. PMID: 34235884.</ref>
**Alternatively, [[Prednisone]] 1 mg/kg/day up to 80 mg as starting dose
**Expeditious steroid therapy prevents stroke of the involved artery or permanent vision loss
*Needs temporal artery biopsy, although treatment with high dose corticosteroids should be initiated prior to biopsy to avoid permanent vision loss as a result of ophthalmic artery involvement.
**Biopsy should be done as soon as possible, but may be positive as long as 2 weeks after steroid initiation<ref>Achkar AA, Lie JT, Hunder GG, O'Fallon WM, Gabriel SE. How does previous corticosteroid treatment affect the biopsy findings in giant cell (temporal) arteritis? Ann Intern Med. 1994 Jun 15;120(12):987-92. doi: 10.7326/0003-4819-120-12-199406150-00003. PMID: 8185147.</ref>

==Disposition==
*Admission

==See Also==
*[[Headache]]

==References==
<references/>

==Videos==
{{#widget:YouTube|id=6nKZ1X-ZYGI}}

[[Category:Ophthalmology]]
[[Category:Neurology]]
[[Category:Rheumatology]]