29th January 2024

Clinical features

Non-specific symptoms such as fever, weight loss and malaise, along with muscle and joint pains, may develop sub-acutely over weeks or months. PAN may affect every organ of the body with a predisposition for the skin, kidneys, nerves and gastrointestinal tract. 

Renal involvement occurs in around 60% of patients, which can present with hypertension and impaired renal function. Skin involvement occurs in 40%, mainly on the legs and can be very painful. Common findings include purpura, livedo reticularis, ulcers, nodules or gangrene. Neurological involvement includes polyneuropathy (mononeuritis multiplex) along with central nervous system presentations such as seizures and stroke. Gastrointestinal involvement can cause abdominal pain, malaena, nausea and vomiting. More serious complications can occur, such as bowel infarction and perforation. Coronary artery involvement occurs in 35% with an increased risk of myocardial infarction.