A 72-year-old Japanese man was admitted to our hospital for surgery for oesophageal cancer. On postoperative day 13, thoracentesis was performed for pleural effusion (Figure 1A). Microbiological culture yielded a monomicrobial isolation of Corynebacterium striatum, for which vancomycin was initiated under the diagnosis of postoperative empyema. Two weeks later, the patient developed back pain, and magnetic resonance imaging revealed acute osteomyelitis that radiologically localised to the anterior region of Th 8 and 9 vertebrae with T1-weighted image (Figure 1B), suggesting a direct extension of the inflammatory process from the empyema. Blood cultures were negative throughout the postoperative course. The antibiotic susceptibility test for the C. striatum isolate showed susceptibility to vancomycin, trimethoprim-sulfamethoxazole, and rifampicin (RFP). Following 3 weeks of intravenous vancomycin treatment with a favourable clinical course, the therapeutic regimen was switched to oral administration of RFP and sulfamethoxazole-trimethoprim combination based on the antibiotic susceptibility test, and the patient was discharged. The antibiotic therapy continued for a total of 6 weeks without recurrence.

This case highlights that empyema caused by C. striatum potentially develops secondary vertebral osteomyelitis. C. striatum can cause pneumonia and empyema, while it is rarely associated with osteomyelitis [1]. Although the organism demonstrates complete susceptibility to vancomycin, switching to oral therapy including RFP has been reported because the sensitivity to RFP is retained [2]. C. striatum can induce postoperative empyema, and RFP represents a viable therapeutic option.

Author Contributions

S.F. drafted and H.H. revised the manuscript; K.N. managed the patient; all authors gave final approval to the submitted manuscript.

Ethics Statement

Written informed consent was obtained from the patient for the publication.

Conflicts of Interest

The authors declare no conflicts of interest.