Vasculitis  

 Clinical features of vasculitis on the basis of size of the affected blood vessel

Size of blood vessel	Blood vessel involved	Clinical features
Small vessel vasculitis (vessels smaller than arteries such as capillaries and venules)	Cutaneous post‐capillary venules	Palpable purpura
	Glomerular capillaries	Haematuria, red cell casts in urine, proteinuria, and decline in renal function
	Pulmonary capillaries	Lung haemorrhage manifesting as breathlessness, haemoptysis and widespread alveolar shadowing on chest radiograph
Medium vessel vasculitis (small and medium sized arteries)	Small cutaneous arteries	Necrotic lesions and ulcers, nail fold infarcts
	Epineural arteries	Mononeuritis multiplex
	Mesenteric artery	Abdominal pain, gastrointestinal bleeding and perforation because of gut infarction
	Branches of coeliac artery	Infarction of liver, spleen, or pancreas
	Renal artery	Renal infarction
	Coronary arteries	Myocardial infarction or angina, coronary artery aneurysm, ischaemic cardiomyopathy
	Small pulmonary arteries	Necrotic lesions leading to cavitating lung shadows on chest radiograph
	Small arteries in ear, nose and throat region	Nasal crusting, epistaxis, sinusitis, deafness, stridor because of sub‐glottic stenosis
Large vessel vasculitis (aorta and its branches)	Extracranial branches of carotid artery	Temporal headache (temporal artery), blindness (ophthalmic artery), jaw claudication (vessels supplying muscles of mastication)
	Thoracic aorta and its branches	Limb claudication, absent pulses and unequal blood pressure, bruits, thoracic aortic aneurysms

Classification of vasculitis on the basis of size of affected blood vessel

• Large vessel vasculitis
  • Giant cell arteritis
  • Takayasu’s arteritis
• Medium vessel vasculitis
  • Polyarteritis nodosa
  • Kawasaki’s disease
• Small vessel vasculitis
  • ANCA associated vasculitis
    • Wegener’s granulomatosis
    • Churg‐Strauss syndrome
    • microscopic polyangiitis
  • Henoch‐Schonlein purpura
  • Cutaneous leucocytoclastic angiitis
  • Cryoglobulinaemic vasculitis
  • General diagnostic approach

There are five important questions to ask when faced with a patient with possible vasculitis (depending on clinical presentation):

1. Is this a condition that could mimic the presentation of vasculitis?
2. Is there a secondary underlying cause?
   1. Secondary causes of vasculitis
      1. Inflammatory diseases of unknown aetiology:
         1. rheumatoid vasculitis
         2. vasculitis associated with systemic lupus erythematosus and Sjogren’s syndrome
         3. inflammatory bowel disease
         4. sarcoidosis
      2. Infectious diseases:
         1. hepatitis B and C
         2. human immunodeficiency virus
         3. mycobacteria
         4. syphilis
      3. Neoplasia:
         1. haematological malignancies such as myeloproliferative and lymphoproliferative disorders
         2. solid tumours
      4. Drugs (almost any drug)
3. What is the extent of vasculitis?
4. How do I confirm the diagnosis of vasculitis?
5. Important investigations to consider during initial evaluation of patients with suspected vasculitis 
   1. To exclude vasculitis “mimics” and secondary causes
      1. Blood cultures
      2. Echocardiogram
      3. Hepatitis screen (B and C)
      4. HIV test
      5. Antiglomerular basement membrane antibody
      6. Antiphospholipid antibodies
      7. Antinuclear antibody
   2. To assess extent of vasculitis
      1. Urine dipstick and microscopy (all patients)
      2. Chest radiography (all patients)
      3. Nerve conduction studies/electromyography/CK
   3. To confirm diagnosis of vasculitis
      1. Biopsy and/or angiogram
   4. To identify the specific type of vasculitis
      1. ANCA
         1. c‐ANCA =
            1. Wegener’s granulomatosis (Very Strongly associated)
            2. Crescentic Glomerulonephritis (moderately associated)
            3. Polyarteritis Nodosa (Weakly associated)
         2. p‐ANCA =
            1. Crescentic Glomerulonephritis (Strongly associated)
            2. Polyarteritis Nodosa (Moderately associated)
            3. Churg-StraussVasculitis (Moderately associated)
            4. Granulomatosis with Polyangiitis (Weakly associated)
            5. Henoch-Schonlein Purpura (Possibly associated)
            6. Temporal Arteritis (Possibly associated)
      2. Cryoglobulin, Complement levels, Eosinophil counts/IgE levels
      3. Specific findings on biopsy (necrotising granulomatous inflammation, presence of IgA deposits, evidence of immune complex formation (or its absence))