Risk factors for infection in haematology patients treated with rituximab

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.

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.

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].

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.