Temporal Arteritis, also know as cranial arteritis or giant cell arteritis (GCA), is a condition that involves the temporal arteries that supply blood to the head and brain. It typically affects the large vessels, but smaller vessels can be involved, as well. These arteries become inflamed and can cause the patient to experience a lot of pain and permanent vision loss. Giant cell arteritis is an ophthalmic emergency and prompt intervention is required to prevent permanent vision loss and significant morbidities (De Smit, et al., 2016).
Incidence and Prevalence
This condition is relatively rare, affecting people over the age of 50, occurring most often between the ages of 70-80 years. Giant cell arteritis (GCA) is a segmental systemic granulomatous arteritis affecting medium and large arteries in individuals >50 yr. The inflammation primarily targets branches of the extracranial head and neck blood vessels (external carotids, temporal arteries, ciliary and ophthalmic arteries. The aorta and subclavian and brachial arteries can also be affected. Intracranial arteritis is rare (Ferri, 2018).
The incidence of GCA is hard to determine because it is poorly reported. A study in 2015 found that the prevalence was 1:10,000 persons over a two year span (Petri, Nevitt, Sarsour, Napalkov, and Collinson, 2015). Most cases are paired with a diagnosis of polymyalgia rheumatic (PMR). There are approximately 20 new cases of temporal arteritis for every 100,000 people over 50 years of age. Incidence increases with age with the highest rate being among those 70-79 years old, is more common in women than in men by 3:1 and is more often seen in Caucasians than any other race (Petri et al.,. 2015). There are no estimates of the prevalence of GCA in the United States population in the current millennium.
Pathophysiology
An inflammatory infiltrate that contains CD4(+) T cells, macrophages, and multinucleated giant cells, groups together causing granulomas in the media of the arterial wall (Ly et al., 2013). It starts destructing the internal wall leading to intimal hyperplasia. These destruction affects all 3 layers of the arterial wall.
Physical Assessment and Examination
Per Mayo Clinic (2015), the most common symptoms of giant cell arteritis are head pain and tenderness, which is often severe and usually affects both temples. The onset of the condition can feel like the flu.
Generally, signs and symptoms of giant cell arteritis include:
- Persistent, severe head pain, usually in your temple area
- Scalp tenderness
- Jaw pain when you chew or open your mouth wide
- Fever
- Fatigue
- Unintended weight loss
- Vision loss or double vision, particularly in people who also have jaw pain
- Sudden, permanent loss of vision in one eye
A new onset of GCA presents most often presents with bitemporal headaches, jaw claudiacation, scalp tenderness, visual disturbances, systemic symptoms such as fever and weight loss, and polymyalgia (Ness et al., 2013).
Diagnosis can be rather difficult, as many of the early signs of this disease are common in many other conditions. Often times, signs and symptoms are often ignored or referral to an ophthalmologist is put off until the patient has lost sight in one eye and this blindness is then permanent.
Generally, providers will first rule out other causes. The provider will complete a thorough physical examination, focusing on the temporal arteries. The arteries may be tender upon palpation and have a cord-like appearance. The provider may order laboratory testing including erythrocyte sedimentation rate and a c-reactive protein which are general indicators of inflammation in the body. There will be an increase in laboratory values of sedimentation rate, and c-reactive protein. Follow-up comparison of these lab results may indicate progress of treatment. Ultrasounds and magnetic resonance imaging (MRI) can also be used for diagnosing. A temporal artery biopsy can also be performed. Mayo Clinic (2015) states that biopsy is the best way to confirm a diagnosis of giant cell arteritis. A small sample of the temporal artery is taken and may show inflammation that includes abnormally large cells, called giant cells. It is still possible to have a negative biopsy in which case a biopsy would be performed on the other side of the patient’s head. Other diagnostic imaging may also include Doppler and PET scan.
Treatment Plan and Patient Education
Treatment for giant cell arteritis consists of high doses of a corticosteroid drug such as prednisone. Because immediate treatment is necessary to prevent vision loss, your doctor is likely to start medication even before confirming the diagnosis with a biopsy.
The initiation of high dose glucocorticosteroids should be administered as soon as GCA is suspected. If there are no vision symptoms or jaw claudication, the original dosage and medication is 40mg prednisone tablets until symptoms are gone. If there are vision changes or jaw claudication, the initial dose should be 60mg prednisone until symptoms are gone. These dosages should be administered once daily. Depending on the extent of the vision loss, intravenous methylprednisolone should be administered for days (Barraclough et al., 2012). Patient education would include information on GCA, the importance of taking the steroids, and the urgency of seeking medical help if any symptoms return.
Follow-up
The steroid dose should be slowly tapered every two weeks, as appropriate. Symptoms should be re-evaluated before every decrease. If at any point symptoms return, patient should immediately return for care.
Serious visual complications including blindness, may occur in 10 to 15 percent of patients if untreated or inadequately treated. Patients will often be referred to an ophthalmologist, neurologist or rheumatologist based on the symptom presentation. Patients will follow-up with their provider and all specialists as needed until the symptoms have resolved or optimally managed.
References:
Barraclough, K., Mallen, C., Helliwell, T., & Hider, S. (2012). Diagnosis and management of giant cell arteritis. The Bristish Journal of General Practice, 62(599), 329-330. doi: 10.3399/bjgp12X649313
De Smit, E., O’Sullivan, E., Mackey, D. A., & Hewitt, A. W. (2016). Giant cell arteritis: ophthalmic manifestations of a systemic disease. Graefe’s Archive For Clinical And Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie, 254(12), 2291-2306.
Ferri, F.F. (2017). 2018 Ferri’s clinical advisor: 5 books in one. Amsterdam: Elsevier.
Ly, K, Liozon, E., Fauchais, A, & Vidal, E. (2013). Pathophysiologyof giant cell arteritis. The Revue de Medicine Interne, 34(7), 392-402. doi: 10.1016/j.revmed.2013.02.037
Mayo Clinic. (2015). Giant cell arteritis. Retrieved from https://www.mayoclinic.org/diseases-conditions/giant-cell-arteritis/symptoms-causes/syc-20372758
Ness, T., Bley, T., Schmidt, W., & Lamprecht, P. (2013). The diagnosis and treatment of giant cell arteritis. Deutsches Arzteblatt International, 110(21), 376-386. doi: 10.3238/arztebl.2013.0376
Petri, H., Nevitt, A., Sarsour, K., Napalkov, P., & Collinson, N. (2015). Incidence of giant cell arteritis and characteristics of patients: data-driven analysis of comorbidities. Arthritis Care & Research, 67(3), 390-395. DOI: 10.1002/acr.22429
