Postoperative neurosurgical infections due to bacillus species

The cases of 2 patients with postoperative ventriculitis due to Bacillus species bacteria are presented. Bacillus licheniformis was isolated from one patient following removal of an intraventricular meningioma, and Bacillus cereus from another patient following placement of a ventriculoperitoneal shunt. Both isolates were resistant to a variety of antibiotics, but both were sensitive to gentamicin and chloramphenicol. These cases emphasize several points: (1) Bacillus species, usually thought to be nonpathogenic, may produce intracranial infections; (2) species identification is important for epidemiological purposes and for the selection of appropriate chemotherapeutic agents; and (3) in cases of suspected ventriculitis, chloramphenicol or gentamicin should be considered for Gram's staining revealing gram-positive bacilli. In addition, we recommend that when planning antibiotic prophylactic regimens, consideration should be given to including one of these agents to assure coverage of Bacillus species.