- Inflammation within or around blood vessels (-/+ necrosis). Severity depends on size and site of vessel involved.
- Causes: idiopathic (50%), CTD (SLE/RA), infection (rheumatic fever, I.E. Lyme’s disease), drugs (NSAIDSs, antibiotics), neoplasia (lymphoma, leukaemia).
- General p/c: skin (=palpable painful purpura on lower legs/buttocks), systemic (=fever, night sweats, malaise, weight loss, myalgia, arthralgia)
- p/c: tender nodules 1-5cm on extensor surfaces of limbs (shins), ankle/wrist arthritis, fever, women, linked to sarcoidosis, COCP, sulphonamides, IBD (UC and crohn’s), maliganancy, TB, strep infection.
- Mx: self-limiting in ~8/52, non-scarring.
Henoch-Schonlein purpura (HSP):
- Children, equal gender split, purpuric rash over buttocks/extensor surfaces, following URTI, urticarial, nephritis, arthralgia, abdo pain.
- Mx: refer to PAU, self-limiting over ~8/52.
Polyarteritis nodosa (PAN):
- Uncommon, male, middle aged, multi-organ necrotizing vasculitisaneurysms of medium sized vessels. Tender subcutaneous nodules along line of arteries, coronary arteritis, HTN, mononeuritis multiplex, renal failure, GI symptoms, linked to Hep B.
- Mx: refer to rheum – for angiography, control BP, high dose steroids and cyclophosphamide.
Churg-Strauss syndrome (eosinophillic granulomatosis of lungs):
- Linked to asthma – mainly affecting pulmonary circulation, also affects coronary/cerebral/splanchnic circulations. Skin manifestations and mononeuritis occur. Diagnosis based on biopsy and raised p-ANCA
- Mx: high dose pred and cyclophosphamide. Avoid leukotriene receptor agonist drugs for control of asthma – will worsen symptoms.
- Granulomatous, multiorgan involvement, mouth ulcers, nasal ulceration, epistaxis, rhinitis, otitis media, CN lesions, lung symptoms and shadows on CXR, HTN, eye signs (50%). Often long prodrome of: nasal stuffiness, headaches, hearing difficulties, nose bleeds.
- Mx: refer to rheum, c-ANCA levels raised, high dose steroids, methoitrexate, mofetil, cyclophosphamide.
- <5yo, fever, bilateral conjunctivitis, polymorphous rash, lip/mouth is red/dry, strawberry tongue, red palms/soles, oedema hands/feet, skin peeling of hands/feet/groin, cervical lymphadenopathy >15mm (usually singular and painful), fever does not respond to anti-pyretics
- Mx: refer to PAU, IV immunoglobulins and aspirin reduce incidence and severity of aneurysms. Late tx = coronary arteritis and aneurysm formation and accelerated atherosclerosis.