Successful use of ibrutinib to control paraneoplastic pemphigus in a patient with paraneoplastic autoimmune multiorgan syndrome and chronic lymphocytic leukaemia

Paraneoplastic pemphigus (PNP) is a rare autoimmune mucocutaneous blistering disease associated with neoplasia. Recently it has become clear that there is concurrent pathological autoimmune-mediated damage that can affect multiple organs other than the skin. Thus the term paraneoplastic autoimmune multiorgan syndrome (PAMS) more accurately reflects the complete disease process. Ibrutinib is a Bruton’s tyrosine kinase (Btk) inhibitor which blocks the B-cell receptor signal pathways and is highly active in several B-cell lymphoproliferative disorders, including chronic lymphocytic leukaemia (CLL) for which it is now approved. Ibrutinib also has potentially useful activity in autoimmune disease. We present the case of a 51-year-old man who developed PNP/PAMS in the context of CLL. He developed severe mucositis and a disseminated mucocutaneous crusted eruption, with deposition of IgG and complement C3 in the basement membrane, together with positive cytoplasmic staining of rat bladder epithelium and presence of desmoglien 3 autoantibodies. His CLL was successfully controlled with ibrutinib. Concurrently, there was significant improvement of his PNP/PAMS, suggesting that ibrutinib may be a very useful addition to the treatment options in this potentially life-threatening autoimmune disorder.

Dr. Andrew Lee