Kikuchi-Fujimoto Disease, A Possible Complication of Rituximab Treatment

ABSTRACT

Rituximab, a chimeric anti-CD20 IgG1 monoclonal antibody, has been used as a rescue therapy for steroid-dependent or refractory nephrotic syndrome. However, the adverse effects of rituximab are yet to be investigated. We report a case of a 9-year-old boy with steroid-dependent nephrotic syndrome who developed Kikuchi-Fujimoto disease after several cycles of rituximab therapy. Kikuchi-Fujimoto disease is a benign, self-limited necrotizing histiocytic lymphadenitis of unknown etiology. In the present case, Kikuchi-Fujimoto disease developed when the peripheral blood B-cell count of the patient was at nadir, and the lesion regressed slowly but spontaneously after recovery of the B-cell count. To our knowledge, although the pathologic diagnosis of Kikuchi-Fujimoto disease was unavailable, this is the first report of Kikuchi-Fujimoto disease with clinical diagnosis as a possible adverse effect of rituximab.