A 73-year-old gentleman presented with drainage from suture sites along his head. He had a history of meningioma that was resected 9 months prior at an outside hospital. His surgical wounds had healed but 1 week prior to presentation he noticed redness and a small bump along the surgical closure line. The night prior, the bump spontaneously drained purulent fluid. He was otherwise well upon arrival to the emergency department but was admitted due to concern for a brain infection. 

CT and MRI were performed and areas of abscess were seen. Biopsies were obtained from under the draining site and sent for culture. Gram stain of the tissues revealed many gram-positive rods; some showing beaded staining. 

Nothing grew on aerobic cultures, however small white colonies grew on anaerobic non-selective media. Biochemical testing confirmed these were catalase and spot Indole positive. 

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Author Information

Jessica Larsen, M(ASCP)CM, Supervisor of Microbiology, Mayo Clinic Arizona
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