Safe and successful treatment of refractory polyarteritis nodosa with tocilizumab in a patient with past hepatitis B virus infection: a case-based review.

Polyarteritis nodosa is a primary systemic necrotizing vasculitis whose evolution follows, in many cases, a chronic remitting-recurrent course with refractoriness to conventional immunosuppressants. We report here the clinical case of a 75-year-old patient with serologies suggestive of past hepatitis B virus infection who presented a flare of polyarteritis nodosa with great secondary functional impairment. She had not responded to several previous immunosuppressants and required high doses of glucocorticoids to control the flare. After the initiation of biological therapy with tocilizumab, the patient experienced a rapid and marked clinical and analytical improvement, going into clinical remission and being able to remarkably lower the corticosteroid dose and stop the rest of the immunosuppressants. There was no evidence of hepatitis B virus reactivation or changes in the titers of any of the parameters related to the aforementioned infection. This clinical case represents the first case reported in the literature about the successful and safe treatment of polyarteritis nodosa with tocilizumab in a patient with serologies suggestive of past hepatitis B virus infection.