title: A Case of Monoclonal Lymphoplasmacytosis of the Bone Marrow with IgM-Positive Russell Bodies.
abstract: A 71-year-old Japanese male patient infected with HCV was diagnosed with thrombocytopenia. Histological examination of the bone marrow aspirate showed numerous lymphoid aggregates with Russell bodies. Immunohistochemistry and flow cytometric analysis demonstrated clonal expansion of CD5+ CD23+ B cells. Russell bodies were positive for IgM and lambda immunoglobulin light chain. The patient also underwent gastric biopsy, which revealed Helicobacter pylori (HP) infection. Subsequent eradication of the bacteria resulted in improvement of his thrombocytopenia. The clinical course remained uneventful at 15-month follow-up, consistent with monoclonal B-cell lymphocytosis. The observed clonal expansion with plasmacytic differentiation may have occurred under the influence of HCV with HP infection.
authors: Department of Pathology, Faculty of Medicine, Saitama Medical University, 38 Moro Hongoh, Moroyama, Iruma-gun, Saitama 350-0495, Japan.
authors: Hidekazu
authors: H
authors: Kayano
authors: Tsuneyuki
authors: T
authors: Shimada
authors: Naoki
authors: N
authors: Wakimoto
authors: Yuichi
authors: Y
authors: Nakamura
authors: Masami
authors: M
authors: Bessho
authors: Hiroshi
authors: H
authors: Yamaguchi
authors: Atsushi
authors: A
authors: Sasaki
authors: Michio
authors: M
authors: Shimizu