[Evans syndrome complicated with multicentric Castleman disease successfully treated with tocilizumab].

A 26-year-old man presented with fever, multiple lymphadenopathies, polyclonal hypergammaglobulinemia, and an elevated serum interleukin-6 (IL-6) level. Multicentric Castleman disease (MCD) was diagnosed by lymph node biopsy. Treatment with prednisolone (PSL) was initiated; however, its efficacy was limited. During PSL tapering, rapidly progressive anemia and thrombocytopenia developed concurrently with increased reticulocyte level, elevated serum LDH level, decreased haptoglobin level, and positive direct Coombs test. Based on these findings, Evans syndrome, which is a concurrent development of autoimmune hemolytic anemia and immune thrombocytopenia, was confirmed. The PSL dose was increased but was ineffective. Therefore, treatment with tocilizumab was initiated, and the clinical findings of both MCD and Evans syndrome improved. The clinical course of this case suggests that tocilizumab could be a treatment option for Evans syndrome complicated with MCD. Three other cases of Evans syndrome complicated with MCD have also been reported; however, this is the first case that shows the efficacy of tocilizumab as treatment for both MCD and Evans syndrome.