What are the recommended first-line treatments for a patient diagnosed with Polyarteritis Nodosa?

The recommended first-line treatment for Polyarteritis Nodosa (PAN) involves immunosuppressive therapy primarily with high-dose glucocorticoids combined with cyclophosphamide in patients with severe or organ-threatening disease. Initial management typically starts with oral or intravenous corticosteroids to rapidly control inflammation and prevent disease progression NICE CG147. For patients presenting with more severe manifestations, such as renal involvement or neuropathy, adding cyclophosphamide is advised to induce remission NICE CG147. In less severe cases, corticosteroids alone may be sufficient initially, with close monitoring for response Kermani et al. 2022. Adjunctive therapies, including supportive care and management of complications, are also important components of treatment NICE CG147. This combined approach is supported by both UK clinical guidelines and recent vasculitis treatment literature, which emphasize early aggressive immunosuppression to improve outcomes Kermani et al. 2022Barut et al. 2016.