Rheum - GCA

Question 1

Which vessels does GCA affect?

Answer 1

Immune-mediated vasculitis affecting medium and large sized arteries, esp. carotid artery and its extracranial branches. Inflammation causes:

1. TEMPORAL ARTERY: headaches
2. OPHTHALMIC ARTERY: visual disturbances due to ischaemic optic neuritis (if GCA remains untreated, 2nd eye may become affected within 1-2 wks)
3. FACIAL ARTERY: jaw claudication

Question 2

describe the common symptoms of GCA

Answer 2

Symptoms can occur in absence of or before dev. of headache.

• headache: severe, may be worse at night, recent onset, temporal or occipital
• scalp tenderness (e.g. when brushing hair)
• jaw claudication: pain comes on gradually during chewing or talking
• visual disturbances: eg blurred vision, amaurosis fugax, diplopia…
• constitutional symptoms: fatigue, myalgia, malaise or fever. About 50% have features of PMR.

Question 3

describe possible signs of GCA

Answer 3

1. any abnormalities on palpation of temporal artery, e.g. absent pulse, beaded, tender or enlarged (normal appearance does not exclude Dx)
2. occular or fundoscopic evidence of ischaemic disease in pts with visual loss
3. bruits may be heard over carotid, axillary or brachial arteries

Question 4

suggest 3 RFs for GCA

Answer 4

• > 60 yrs
• caucasian
• female

Question 5

which investigations would you perform in a pt with suspected GCA?

Answer 5

Bloods:

• ESR: raised to >50 mm/hr in 80%
• CRP: sometimes raised in presence of normal ESR
• FBC: normocytic normochromic anaemia and thrombocytosis common
• LFTs: may be raised, esp. ALP

Other:

• colour duplex USS: relatively accurate for Dx
• temporal artery biopsy: 87% sensitivity

Question 6

what would temporal artery biopsy show in GCA?

Answer 6

• giant cells (granulomas) in elastic lamina (between tunica intima and media)
• may show nothing as GCA is segmental

Question 7

how would you treat a pt with GCA?

Answer 7

Refer to rheumatology.

1. Immediate steroids once Dx suspected:
   - 40 mg PREDNISOLONE (no ischaemic Sx)
   - 60 mg PREDNISOLONE (if claudication Sx)
   - admit for IV METHYLPREDNISOLONE (if visual Sx). Gradually reduce once Sx and tests resolve.
2. 75 mg ASPIRIN (unless CI) - shown to reduce rate of visual loss and strokes (+ PPI)
3. Bisphosphonates for osteoporosis prophylaxis due to glucocorticoid toxicity, e.g. ALENDRONATE 10 mg

Question 8

suggest possible complications of GCA

Answer 8

1. spontaneous relapses - common and unpredictable, most pts able to stop taking steroids by 2 yrs
2. loss of vision
3. aneurysms, dissections and stenotic lesions of aorta and major branches
4. CNS disease, e.g. seizures, CVAs, ischaemia