An unusual presentation of polyarteritis nodosa: A case report.

Polyarteritis nodosa (PAN) is a rare form of vasculitis which involves medium and small sized arteries. It can involve any system of the body, but lungs are typically spared. PAN typically presents with non-specific symptoms, such as fever, weight loss and myalgias, and symptoms related to the system involved. Negative serum ANCA helps in differentiating it from other similarly presenting vasculitis and definitive diagnosis is made on histopathology. Limb ischaemia is a rare presentation as well as a rare complication of PAN. We present the case of a 28-year-old female who presented with severe lower limb ischaemia and intermittent leg claudication as initial symptoms which led to initial diagnosis of critical limb ischaemia. Later in the course of the illness she developed gastrointestinal symptoms and weight loss. She was diagnosed as having PAN based on laboratory results and histopathological evidence. Intravenous steroids halted the progress of the disease, but the patient required transmetatarsal amputation of the foot to remove dead tissue. Vasculitis like PAN, although much rarer than atherosclerotic peripheral vascular disease (PVD), should be considered as a differential diagnosis in cases of limb ischaemia in which there is lack of risk factors for PVD.