[Intravenous immunoglobulin in combination with ibrutinib for the treatment of IgM-type M protein associated peripheral neuropathy complicated with chronic lymphocytic leukemia].

We report the case of a 79-year-old man with chronic lymphocytic leukemia (CLL) with IgM-kappa type monoclonal gammopathy according to immunophenotypes and a negative result for MYD88 L265P mutation of leukemic cells. Abnormal lymphocytes and IgM increased under observation, and he experienced paresthesia. The diagnosis of IgM-type M protein associated peripheral neuropathy was confirmed by nerve conduction test, and negativity of myelin-associated glycoprotein and glycolipid antibodies. He was placed on intravenous immunoglobulin (IVIg) in combination with ibrutinib. His symptoms dramatically subsided and did not recur. Treatment with IVIg and ibrutinib may be useful for the rare complication of peripheral neuropathy with CLL.