Risk factors for infection in haematology patients treated with rituximab.

ABSTRACT

OBJECTIVES: Although rituximab therapy is not considered to be closely associated with infection, there have been reports of serious infections in patients treated with rituximab. We performed a statistical retrospective analysis to clarify the risk factors for infection in patients receiving rituximab therapy. METHODS: A retrospective study of data from clinical records was performed that targeted haematology patients treated at our university hospital between April 2003 and October 2006. We selected 63 patients with CD20-positive lymphoma whose peripheral blood immunoglobulin levels had been measured within 6 months before and after rituximab therapy. Logistic regression analysis was used to investigate the risk factors for serious infection in these patients. RESULTS: The three risk factors identified were 1) reduction in IgM after administration of rituximab [odds ratio (OR) = 1.032, confidence interval (CI) = 1.007-1.057; P = 0.009], 2) duration of rituximab therapy [OR = 0.962, CI = 0.932-0.994; P = 0.021] and 3) G-CSF administration [OR = 4.825, CI = 1.411-16.495; P = 0.012]. CONCLUSIONS: Rituximab therapy may be associated with infection, indicating the need for sequential monitoring of IgM levels and identification of the optimal interval between rituximab cycles.