Differentiating Juvenile Myelomonocytic Leukemia From Infectious Disease

Two recent articles in BLOOD 1,2 review the findings and outcome of juvenile myelomonocytic leukemia (JMML). Both omit an important aspect of JMLL: its differentiation from infectious disease. Several disseminated microbial infections of infancy can result in persistent fever, failure to thrive, hepatosplenomegaly, skin lesions, anemia, thrombocytopenia, and myelomonocytosis, including Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes virus-6 (HHV-6), histoplasma, mycobacteria, and toxoplasma. Thorough investigation for infection is needed in infants with these findings to avoid erroneous diagnosis and mistaken interventions.