Mannose-binding lectin (MBL) and the risk for febrile neutropenia and infection in pediatric oncology patients with chemotherapy

Background: We determined whether mannose-binding lectin (MBL) deficiency is associated with an increased risk of febrile neutropenia (FN) and/or infection in pediatric oncology patients. Procedure: We systematically searched and reviewed all the literature on MBL and infections in children with cancer, identified from a literature search of Medline, Embase, and Central (1966-April 2010). We extracted information on the type of study, patient characteristics, definition of MBL deficiency, definition of infection and method of detection, follow-up period and the results of the outcome in different groups. The validity of each study was assessed. Results: Six cohort studies were retrieved, consisting of 581 children with leukemia (n=2) or varying types of cancer (n=4). Many different outcome definitions were used. In only one out of three genotype studies, variant MBL2 genotypes, as well as MBL levels <1,000μg/L, were associated with an increased duration of FN. In one additional MBL level study the number of FN episodes, bacteremia and severe bacterial infection were increased in patients with MBL levels <100μg/L as compared to those with MBL levels of 100-999μg/L. Sepsis, pneumonia, viral infection, and fungal infection were not associated with either MBL levels or genotypes in any of the studies. Conclusions: MBL deficiency could not be identified as an independent risk factor for FN or infection in pediatric oncology patients. A multicenter study of children with comparable chemotherapy regimens, relevant and equal outcome definitions and measuring both MBL levels and genotypes, will be required to avoid clinical and methodological inconsistencies.