Giant Cell Arteritis Diagnosis and Treatment May Undergo Changes

September 24, 2020

The approval of tocilizumab for giant cell arteritis as a glucocorticoid-sparing treatment is the most significant development in the management of this condition over the past four years, a review of the literature suggests.

The approval of tocilizumab for giant cell arteritis as a glucocorticoid-sparing treatment is the most significant development in the management of this condition over the past four years, a review of the literature suggests.

New studies with positron emission tomography (PET) and computed tomography (CT) have not changed the approach to diagnosis, and glucocorticoids remain the first choice to manage both giant cell arteritis and polymyalgia rheumatica, according to Frank Buttgereit, MD, from Charité University Medicine, in Berlin, Germany, and colleagues.

In addition to updating their 2016 systematic review of the two conditions, the authors recommend an algorithm for their diagnosis and management, in JAMA Network.

Both polymyalgia rheumatica and giant cell arteritis almost exclusively affect people 50 years of age and older, and both can cause fever, fatigue, weight loss, depression, night sweats while raising inflammatory markers, such as the level of c-reactive proteins and the rate of erythrocyte sedimentation.

Polymyalgia rheumatica also causes acute bilateral upper extremity pain, which often worsens with or following rest. Giant cell arteritis often causes headache and sometimes acute vision loss.

The prevalence of polymyalgia rheumatica was estimated at 701, and the prevalence of giant cell arteritis was estimated at 204 for every 100,000 people 50 years of age and older, in a study of 2015 data.

Clinical features, inflammatory markers and imaging provide the cornerstones of diagnosis. Bilateral subdeltoid bursitis can indicate polymyalgia rheumatica, while vascular inflammation can indicate giant cell arteritis.

In their treatment algorithm, Buttgereit et al. recommended the following algorithm:

Start with an induction therapy of glucocorticoids at an oral prednisone equivalent dose of 40-60 mg/d, then consider the addition of tocilizumab or methotrexate.

After 2-4 weeks of clinical improvement, taper the glucocorticoid dose by 10 mg every 2 weeks to 20 mg/d.

If a flare occurs, increase the glucocorticoid dose again by 5-10 mg, then taper over 4-8 weeks to the dose before the relapse and consider adding 162 mg/wk of tocilizumab or 7.5-15 mg/wk of methotrexate.

If the patient remains stable at 20 mg/d of glucocorticoid, continue tapering this drug by 1-1.2 mg every 2-8 weeks until discontinuation, and then withdraw the tocilizumab or methotrexate. However, if signs and symptoms return, or if there are ischemic complications, start the induction therapy over again.

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REFERENCES

Buttgereit F, Matteson EL, Dejaco C. Polymyalgia Rheumatica and Giant Cell Arteritis. JAMA. 2020;324(10):993–994. doi:10.1001/jama.2020.10155

Buttgereit F, Dejaco C, Matteson EL, Dasgupta B. Polymyalgia Rheumatica and Giant Cell Arteritis: A Systematic Review. JAMA. 2016;315(22):2442–2458. doi:10.1001/jama.2016.5444