Common GCA and PMR exam questions for medical finals, OSCEs and MRCP PACES
What are the classic presenting features of giant cell arteritis (GCA)?
- Temporal headache
- Jaw claudication
- Scalp tenderness
- Tenderness and/or thickening of one of the temporal arteries
- Visual impairment (involvement of ophthalmic artery)
- Systemic features: anorexia, fever, sweats, malaise
What are the ACR diagnostic criteria for giant cell arteritis (GCA)?
- Age >50 years
- New onset headache
- Abnormalities of the temporal arteries on palpation
- ESR >50 mm/hour
- Abnormal temporal artery biopsy.
- The presence of three or more criteria has a sensitivity of 97% and a specificity of 79% for a diagnosis of giant cell arteritis.
How would you investigate suspected giant cell arteritis (GCA)?
- Bloods, CXR, urine dip
- Temporal artery biopsy
- Can be done within 14 days of starting steroid treatment but loses sensitivity over time. May be negative due to skip lesions
- Shouldn’t delay steroids for biopsy
- PET scan if suspicion of large vessel involvement
- E.g. Marked systemic features, high inflammatory markers despite steroid treatment
- Colour duplex of temporal arteries
- Sensitivity (and negative predictive value) 95%
How would you treat giant cell arteritis (GCA)?
- If no visual involvement: 40-60mg prednisolone OD
- Symptoms should improve in 7-14 days
- Taper dose after 1-2 months gradually
- By 10mg every 2/52 to 20mg, then by 2.5mg every 2-4/52 to 10mg, then by 1mg every 1-2 months
- Vision loss/amaurosis fugax
- IV methylprednisolone 500mg-1g od for 3 days
- Consider 60mg prednisolone PO if established visual loss