Large vessel vasculitis - Horton disease, Takayasu’s arteritis, Buerger disease
Horton disease (Giant Cell Arteritis)
Giant cell arteritis, also known as temporal arteritis as it usually impacts the temporal artery, is a type of arteritis that affects large and medium sized arteries, including branches of the aortic arch (similar to Takayasu’s). The mean onset is about 67 years of age, while women are more likely to get it than men. Typical symptoms include headache, visual disturbances, polymyalgia rheumatica, jaw claudication and fever.
The inflammatory process of GCA is mediated by T-cells and macrophages which invade the endothelium of the vessel and lead to granuloma formation which goes on to disrupt the layer between the tunica intima and the media of the artery. This process narrows the vessel lumen, resulting in ischemia and producing the symptoms described above.
Image: “Histopathology of giant cell arteritis” by Abhishek Lunagariya, Chintan Rupareliya, Pradeep C. Bollu, Zabeen Mahuwala, CC BY 3.0, via Wikimedia Commons.
If ⅗ of the american college of rheumatology criteria for GCA are met then consider diagnosis:
- Age >50
- New onset headache
- Temporal artery tenderness or pulsation
- ESR >50mm/hour
- Abnormal artery biopsy showing granulomatous inflammation
Treat with oral prednisolone as first line (same day) 60mg.
Takayasu’s arteritis
This is a chronic inflammatory disease of unknown cause, median onset 29 years, and it is eight times more frequent in women than in men, it is also more frequent in asia and africa than in europe or north america. Its characteristic feature is inflammation of the aorta and its branches, and occasionally the pulmonary artery as well. It can be diffuse or patchy.
The disease causes intimal hyperplasia, medial degeneration and obliterative changes, mostly causing stenotic lesions in the vessels, although aneurysms have been known to occur.
Most patients have additional systemic symptoms such as fatigue, fever, headache, sweats, arthralgia and weight loss. As the disease progresses vascular insufficiency developes, this can present as absent pulses and diminished BP in the upper extremities. Around half of patients have renal involvement leading to secondary hypertension, and aortic valve insufficiency can also occur.
Laboratory analysis will show raised CRP, raised ESR, anemia, mild leukocytosis and elevated immunoglobulin levels. Diagnosis is with CT angiography or MR angiography. Treat with prednisolone 60-100mg/day for months until evidence that inflammation has subsided.