1990 American College of Rheumatology Classification Criteria for Polyarteritis Nodosa (PAN)
- Weight loss > 4 kg: loss of ≥ 4 kg since illness began not due to other factors
- Livedo reticularis: mottled reticular pattern on extremities or torso.
- Testicular pain or tenderness: not due to infections, trauma or other causes.
- Myalgias, weakness or leg tenderness: diffuse myalgia (excluding shoulders and hip girdle) or weakness of muscles or tenderness of leg muscles.
- Mononeuropathy or polyneuropathy
- Diastolic blood pressure > 90 mmHg
- Elevated BUN or creatinine: BUN > 40 mg/dl (14.28 mmol/L) or creatinine > 1.5 mg/dl (132.6 µmol/L)
- Hepatitis B virus
- Arteriographic abnormality: arteriogram showing aneurysms or occlusions of the visceral arteries, NOT due to arteriosclerosis, fibromuscular dysplasia or other non-inflammatory causes.
- Biopsy of small or medium-sized artery containing PMN: granulocytes or granulocytes and mononuclear leukocytes in the artery wall.
Requirements: ≥ 3 of the above 10 criteria are required for classification as PAN. Sensitivity 82.2%, specificity 86.6%.
Reference: Lightfoot et al. The American College of Rheumatology 1990 criteria for the classification of polyarteritis nodosa. Arthritis Rheum 1990;33:1088-93.