We report a case of acute myeloid leukemia(AML)that developed after allogeneic hematopoiet(ic) stem cell transplantation(allo-HSCT),initially presenting as recurrent low back pain.The patient was finally diagnosed with a spinal Stenotrophomonas maltophilia infection by metagenomic next-generation sequencing(mNGS)and was successfully treated with a combination of compound sulfamethoxazole tablets and levofloxacin.