1990 Criteria For the Classification of Polyarteritis Nodosa

1. Weight loss ≥4 kg

Loss of 4 kg or more of body weight since illness began, not due to dieting or other factors

2. Livedo reticularis

Mottled reticular pattern over the skin or portions of the extremities or torso

3. Testicular pain or tenderness

Pain or tenderness of the testicles, not due to infection, trauma, or other causes

4. Myalgias, weakness or leg tenderness

Diffuse myalgias (excluding shoulder and hip girdle) or weakness of muscles or tenderness of leg muscles

5. Mononeuropathy or polyneuropathy

Development of mononeuropathy, multiple mononeuropathys, or polyneuropathy

6. Diastolic BP >90 mm Hg

Development of hypertension with diastolic BP higher than 90 mm Hg

7. Elevated BUN or creatinine

Elevation of BUN >40 mg/dl or creatinine >1.5 mg/dl, not due to dehydration or obstruction

8. Hepatitis B virus

Presenece of hepatitis B surface antigen or antibody in serum

9. Arteriographic abnormality

Arteriogram showing aneurysms or occlusions of the visceral arteries, not due to arteriosclerosis, fibromuscular dysplasia, or other noninflammatory causes

10. Biopsy of small or medium-sized artery containing PMN

Histologic changes showing the presence of granulocytes or granulocytes and mononuclear leukocytes in the artery wall

* For classification purposes, a patient shall be said to have polyarteritis nodosa if at least 3 of these 10 criteria are present. The presence of any 3 or more criteria yields a sensitivity of 82.2% and a specificicy of 86.6%. BP = blood pressure; BUN = blood urea nitrogen; PMN = polymorphonuclear neutrophils.

Lightfoot RW Jr, Michel BA, Bloch DA, Hunder GG, Zvaifler NJ, McShane DJ, et al. The American College of Rheumatology 1990 criteria for the classification of polyarteritis nodosa. Arthritis Rheum 1990;33:1088---93.