Efficacy of rituximab in refractory polyarteritis nodosa: a case report

Polyarteritis nodosa (PAN) is a systemic vasculitis affecting medium and small-sized vessels resulting in multiple organ involvement. Refractory PAN requires a different therapeutic approach. We herein report the case of a 42-year-old male presenting a non-virus-related refractory PAN with a favorable outcome on rituximab. He presented significant weight loss, muscle weakness, peripheral axonal neuropathy, and medium-sized cutaneous vessel necrotizing vasculitis. The patient received high-dose corticosteroids and cyclophosphamide with no significant clinical improvement while developing adverse side effects such as hypertension and diabetes. Rituximab was prescribed as an alternative therapy at 1000 mg on day 0 and day 15. This allowed for complete and rapid control of disease activity with regression of cutaneous injury and substantial improvement of neurological symptoms. In conclusion, using chimeric anti-CD20 monoclonal antibodies, such as rituximab, although rarely reported in refractory non-virus-related PAN, may be an effective alternative therapy, as portrayed in our case.