According to the results of the largest adult cohort, MBL deficiency is not correlated with more frequent or more prolonged febrile episodes during myelosuppressive chemotherapy in adults with hematological cancer, but severe infections are more frequent in MBL-deficient patients and first severe infection develops earlier in this group compared with nondeficient patients [8]. This evidence concerns the gene MBL2 and hematopoietic and lymphoid cell neoplasm.