Survival of a case of Bacillus cereus meningitis with brain abscess presenting as immune reconstitution syndrome after febrile neutropenia - a case report and literature review.

Bacillus cereus sometimes causes central nervous system infection, especially in compromised hosts. In cases of meningitis arising during neutropenia, CSF abnormalities tend to be subtle and can be easily overlooked, and mortality rate is high. We report a survived case of B. cereus meningitis/brain abscess in severe neutropenia, presenting as immune reconstitution syndrome.A 54-year-old Japanese female with acute myelogenous leukemia developed B. cereus bacteremia and meningitis during consolidation chemotherapy. At the onset, she presented with mild meningism. She had marked leukocytopenia (WBC <100/μL, neutrophils 0/μL) and lumbar puncture yielded only mild pleocytosis. She was transferred to intensive care unit, and meropenem, linezolid and vancomycin was started. With intensive therapy, she recovered and once became afebrile. On day 19, however, her fever, meningism and consciousness level dramatically worsened despite recovery of bone marrow function. The antimicrobial chemotherapy was continued and finally she was cured with no complications.With early diagnosis and prompt initiation and of antibiotics, the case was successfully treated without any sequelae. It is important to remember that, even under optimal antimicrobial therapy, bone marrow recovery can cause transient reaggravation of the disease. In such cases, timely and appropriate evaluation should be done to make the clinical decision to change, continue, or intensify treatment.