A case of tumour necrosis factor-α inhibitor- and rituximab-induced plantar pustular psoriasis that completely resolved with tocilizumab.

Rituximab, a chimeric B-cell-depleting monoclonal antibody, is a well-established therapy for rheumatoid arthritis. It is emerging that classical psoriatic lesions and plantar pustular psoriasis (PPP) are cutaneous side-effects of this drug. Antitumour necrosis factor (anti-TNF) therapies have multiple documented side-effects including PPP and psoriasis. We report a patient who has rheumatoid arthritis, who failed on anti-TNF therapies and then was commenced on rituximab. Subsequently she developed localized PPP. Due to deterioration of her joint disease she was switched to the interleukin-6 blocker tocilizumab, and the PPP resolved.