GCA Flashcards
definition of giant cell arteritis
Granulomatous inflammation of large arteries, particularly branches of the external carotid artery, most commonly the temporal artery
aetiology of GCA
unknown
increasing age, genetic and ethnic background and infection may have causitive roles
Associated with HLA-DR4 and HLA-DRB1.
both humoral and cellular immune systems implicated
thickening adn inflammation in vessel wall = narrowing of lumen = ischemia
epidemiology of GCA
men more
65-70yrs
common in the elderly
Annual incidence is 18 in 100000
sx of GCA
headache - temporal artery
temporal artery and scalp tenderness eg when combing hair
visual disturbances - amourosis fugaz or sudden unilateral blindness - opthalmic/retinal/posterior ciliary arteries
jaw claudication - artery to masseter
systemic features
symptoms of polymyalgia rheumatica
headache in GCA
scalp and temporal tenderness - pain on combing hair
jaw and tongue claudication
visual disturbances in GCA
blurred vision
sudden blindness in 1 eye - amaurosis fugax (gradual descending mono-ocular curtain of vision loss.)
systemic features in GCA
malaise
low grade fever
lethargy
weight loss
depression
dyspnoea
morning stiffness
unequal or weak pulses
sx of polymyalgia rheumatica and why found in GCA
early morning pain and stiffness of the muscles of the shoulder and pelvic girdle
(40–60% of cases of GCA are associated with PMR).
signs of GCA
swelling and erythema over the temporal artery
scalp and temporal tenderness
thickened non-pulsatile temporal artery
reduced visual acuity
Ix for GCA
blood - high ESR and CRP, FBC = normocytic anaemia of chronic disease, high platelets, high ALP
temporal artery biopsy - giant cells. Granulomatous. Within 48 h of starting corticosteroids. - negative biopsy does not exclude the diagnosis, because skip lesions occur.
or FDG-PET
temporal artery US - halo sign
Mx for GCA
Start on high dose oral prednisolone (40–60 mg/day) immediately - prevent visual loss
most get immense symptomatic relief in 48hr of commencing steroid therapy
reduce dose of prednisolone gradually - according to symptoms and ESR - to keep dose of 7.5-10mg/day
many pts require prednisolone for 1-2yrs
low dose aspirin (and PPI for gastroprotection) - reduce risk of visual loss, TIA or stroke
osteoporosis prevention - adequate dietary Ca and vit D intake, bisphosphonates
if complicated by visual loss or history of amaurosis fugax - IV pulse methylprednisolone (1 g for 3 days) followed by oral prednisolone (60 mg/day, as above)
tocilizumab - Anti-IL6 receptor Ab for severe/relapsing
Annual CXR for up to 10 years to identify thoracic aortic aneurysms. If detected, monitor with CT every 6–12 months.
complications of GCA
carotid artery or aortic aneurysms
thromobosis may occur followed by recanalisation or embolism to the opthalmic artery = visual disturbances, amaurosis fugax or sudden monocular blindness
irreversible bilateral visual loss - can occur suddenly if not treated
prognosis for GCA
In most cases the condition lasts for approx 2 years before complete remission.
reduce prednisolone once sx have resolved and ESR reduced
increase dose if recurrence
