Table 5

 Classification criteria for childhood polyarteritis nodosa

*Should include conventional angiography if magnetic resonance angiography is negative.
†Glomerular filtration rate of less than 50% normal for age.
A systemic illness characterised by the presence of either a biopsy showing small and mid-size artery necrotising vasculitis OR angiographic abnormalities* (aneurysms or occlusions) (mandatory criteria), plus at least two of the following:
• Skin involvement (livedo reticularis, tender subcutaneous nodules, other vasculitic lesions)
• Myalgia or muscle tenderness
• Systemic hypertension, relative to childhood normative data
• Mononeuropathy or polyneuropathy
• Abnormal urine analysis and/or impaired renal function†
• Testicular pain or tenderness
• Signs or symptoms suggesting vasculitis of any other major organ system (gastrointestinal, cardiac, pulmonary, or central nervous system)