Lasting shift in the gut microbiota in patients with acute myeloid leukemia.

Previous studies have shown that the gut microbiota of patients with acute myeloid leukemia (AML) is disrupted during induction chemotherapy; however, the durability of microbiota changes is unknown. This is an important knowledge gap, because reduced microbiota diversity at the time of stem cell transplantation weeks to months after the initial chemotherapy has been associated with higher mortality after transplantation. By sequencing the gut microbiota in 410 longitudinal stool samples from 52 patients with AML, we found that, during inpatient chemotherapy, the gut microbiota is stressed beyond its ability to recover its original state. Despite major reductions in antibiotic pressure and other disturbances to the microbiota after hospital discharge, the trajectory of microbiota recovery yields new communities that are highly dissimilar to baseline. This lasting shift in the gut microbiota is relevant for subsequent phases of curative therapy and is a potential target for novel microbiota protective/restorative interventions. This trial was registered at www.clinicaltrials.gov as #NCT03316456.