Pembrolizumab-induced autoimmune haemolytic anemia in a patient with chronic lymphocytic leukaemia successfully treated with ibrutinib.

We present a unique case of a patient with a long-standing history of indolent chronic lymphocytic leukaemia (CLL) who suddenly developed autoimmune haemolytic anaemia after starting immune checkpoint inhibitor therapy for bladder cancer. He had no clear indication to start CLL-directed treatment based on current clinical practice guidelines; however, targeted treatment of CLL with ibrutinib proved to be effective in treating the haemolytic anaemia.