Tudesq JJ, et al. - This study offers information regarding the clinical and microbiological features and outcome of the infections in patients treated with rituximab for autoimmune and/or malignant hematological disorders. Based on the findings, it was concluded that rituximab-related infectious events can be extremely severe, especially in patients immunocompromised by several other drugs. The focus of further explorations should be the group with life-threatening polymicrobial infections.

Methods

• The medical records of patients treated with rituximab in an internal medicine department of a tertiary hospital between 2007 and 2015 were retrospectively analyzed, and all iE after this therapy were identified.
• Using the Common Terminological Criteria of Adverse Events (version 4.3) definitions, events’ severity was evaluated.

Results

• A total of 101 patients were treated with rituximab, of these, 228 IE were identified in 74 (73.3%) (median follow-up 30.4 months).
• Either autoimmune disease (AID) (52.5% of patients), or monoclonal hematological disease (MHD) (47.5%) indicated rituximab.
• Findings revealed that patients received an overall median number of 5 rituximab infusions [interquartile range: 4-8], representing a cumulative dose of 4340mg [2620-6160].
• The occurrence of IE after last rituximab infusion was reported after 3.1 months [0.7-9.4].
• Researchers found that, respectively, IE were severe in 28.1% of cases in patients treated for AID vs 58.0% in patients treated for MHD (p < 0.001), due to opportunistic pathogens in 7.8% vs 11.0% (p=0.49) and fatal in 4.7% vs 13.0% (p=0.044).
• Polymicrobial infection (p < 0.001), monoclonal hematological disease (p=0.035), use of steroids over 10mg/d within the last two weeks (p=0.003), and rituximab cumulative dose (p < 0.001) were found to be associated with mortality.
• In addition, a group of 10 patients (9.9%) was identified, exhibiting life-threatening, polymicrobial, and opportunistic infections constituting a ‘catastrophic infectious syndrome’, which was lethal in 7 cases.