giant cell arteritis

Question 1

definition of GCA

Answer 1

Giant cell arteritis (GCA) is a granulomatous (immune-mediated) vasculitis of large and medium-sized arteries. It primarily affects branches of the external carotid artery, and it is the most common form of systemic vasculitis in adults. GCA typically occurs in people 50 years of age or older and is more common in women. Symptoms of polymyalgia rheumatica are frequently present. The most common serious consequence of GCA is irreversible loss of vision due to optic nerve ischaemia. GCA is sometimes also referred to as temporal arteritis, cranial arteritis, or granulomatous arteritis.

Question 2

risk factors

Answer 2

> 50 y/o
female

smoking
atherosclerosis

Question 3

symptoms and signs

Answer 3

• headache (usually over temporal and occiptal areas) + scalp tenderness
• polymyalgia rheumatica symptoms (aches and stiffness in neck, shoulder, hips + swelling)
• extremity claudication -> usually in jaw
• other cranial artery abnormalities (Other vessels, such as the occipital, postauricular, or facial arteries, may be enlarged or tender.)
• may have trigeminal neuralgia -> CN exam may be abnormal + jaw pain etc.
• jaw claudication
• vision loss
• absent temporal artery pulse
• abnomral fundoscopy
• neurological symptoms (Include hemiplegia, weakness, dysphasia, dysarthria, and balance difficulties)
• cough, sore throat, hoarseness
• bruit auscultation of the carotid, supraclavicular, axillary, or brachial areas in patients with large-vessel involvement.
• asymmetric BP

Question 4

investigations

Answer 4

1st investigations: ESR, CRP, FBC, LFTs, temporal artery biopsy, temporal artery ultrasound

others:
aortic arch angiography

** if temporal artery biopsy is negative, DOES NOT EXCLUDE GCA because it may be other arteries involved

Question 5

PMR vs GCA

Answer 5

Typical symptoms of PMR include aching and stiffness in the shoulders and proximal limb muscles, with or without mild polyarthritis or tenosynovitis. Although GCA and PMR frequently co-exist, cranial symptoms including headache, jaw claudication, and vision symptoms are typically absent in patients with PMR. PMR typically has less prominent symptoms than GCA.

Question 6

solid organ cancers or haematological malignancies vs GCA

Answer 6

Clinical presentation may be similar in solid-organ cancers and haematological malignancies, especially multiple myeloma and lymphoma.

A thorough physical examination, including careful breast exam should be performed as well as age-appropriate cancer screening studies (e.g., mammogram). Haematological studies including protein electrophoresis, lymphocyte immunophenotyping, and bone marrow biopsy may reveal evidence of multiple myeloma. CXR and CT may reveal enlarged nodes in lymphoma.

Question 7

takayasu’s arteritis vs GCA

Answer 7

The major factors differentiating TA from GCA are age at disease onset and lack of involvement of cranial arteries. Typically occurs in young women, usually in their 20s and 30s. Although systemic symptoms are also common in TA, cranial symptoms are usually absent. Patients with TA often have absent or asymmetric peripheral pulses and multiple arterial bruits.

Occasional mild, chronic TA may not be diagnosed until after the patient is 50 years old. They may have had longstanding symptoms of decreased aortic or aortic branch outflow, such as dizzy spells, or been noted as having an unexplained lack of a pulse in one arm.

Question 8

rheumatoid arthritis vs GCA

Answer 8

Symmetric small joint polyarthritis and extra-articular manifestations are characteristic of rheumatoid arthritis and distinguish this condition from GCA.

RA may have positive rheumatoid factor and anticyclic citrullinated peptide antibodies. May have radiographic, ultrasound, or MRI evidence of joint erosions.

Question 9

amyloidosis vs GCA

Answer 9

Amyloidosis can rarely cause jaw and tongue claudication, although these are very characteristic of GCA.

Serum immunoelectrophoresis may show a monoclonal band. Amyloidosis is distinguishable from GCA by lack of response to therapy and by staining of a temporal artery specimen for amyloid. Rectal or abdominal fat biopsy and serum amyloid P scan may be positive.

Question 10

SLE vs GCA

Answer 10

Distinguishing features are the presence of photosensitivity, skin rash, oral ulcers, and symptoms of pleuropericarditis.

In SLE, may see positive antinuclear antibody, antibody to double-stranded DNA, or antibodies to extractable nuclear antigens. Laboratory evidence of cytopenias or glomerulonephritis.

Question 11

treatment

Answer 11

suspected GCA

• > NO visual or neuro signs:
  1. prednisolone
• > visual or neuro signs:
  1. methylprednisolone IV

confirmed GCA
1. high dose prednisolone orally (40-60mg) (taper down after 5-7 days tased on symptoms and ESR)
+ calcium, vit D, bisphosphonate (osteoporosis prophylaxis)
+ aspirin (analgesia as needed)

2. • methotrexate or tocilizumab (for patients with lower glucocorticoid tolerance to taper the steroids off faster)

Question 12

complications

Answer 12

• large vessel stenoses (Clinically significant stenoses of branches of the aortic arch, especially the subclavian and axillary arteries, occur in about 10% to 15% of patients.)
• aortic aneurysm
• vision loss/blindness
• steroid-related effects

Question 13

physical examination in GCA

Answer 13

• may see scalp tenderness
• may have remarkable CN exam (CN neuralgia e.g. trigeminal nerve neuralgia)
• may have thickened and tender temporal arteries
• check for visual loss

Question 14

prognosis

Answer 14

complete remission expected in 2 years