title: [Brain abscess induced by Bacillus licheniformis complications in acute myeloid leukemia (AML)].
abstract: A 64-year-old woman with acute myeloid leukemia, headache, vomiting, and fever exceeding 38.5 degrees C on day 15 during severe neutropenia while undergoing second consolidation chemotherapy presented the next day, with an altered mental state. A space-occupying lesion with ring enhancement was detected in her right frontal lobe on CT, indicting a brain abscess. Treatment was started with 2g/day of meropenem and 2 g/day of vancomycin. Surgical drainage was conducted on day 22 after recovery of her neutrophil and platelet counts. Culture of aspirated pus showed Gram-positive rods subsequently identified as Bacillus licheniformis. Meropenem was administered for 87 days and vancomycin for 44 days. The patient's general condition improved without neurological complications, and her enhanced brain lesion disappeared on day 185. B. licheniformis is often encountered in diagnostic laboratory culture and usually dismissed as a contaminant, but must be considered as a causative agents for brain abscesses in immunocompromised hosts.
authors.affiliation: Hematology/Transplantation, Seirei Numazu Hospital.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Mochiduki
authors.forename: Tokunao
authors.initials: T
authors.lastname: Amemiya
authors.forename: Masami
authors.initials: M
authors.lastname: Yabe
mesh_terms: D001407:Bacillus; D001922:Brain Abscess / Q000150:complications*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000209:etiology*; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000150:complications*; D008875:Middle Aged; D009894:Opportunistic Infections