Intervertebral disc penetration by antibiotics used prophylactically in spinal surgery: implications for the current standards and treatment of disc infections

PurposeThe presence of Propionibacterium acnes in a substantial component of resected disc specimens obtained from patients undergoing discectomy or microdiscectomy has led to the suggestion that this prominent human skin and oral commensal may exacerbate the pathology of degenerative disc disease. This hypothesis, therefore, raises the exciting possibility that antibiotics could play an important role in treating this debilitating condition. To date, however, little information about antibiotic penetration into the intervertebral disc is available. MethodsIntervertebral disc tissue obtained from 54 microdiscectomy patients given prophylactic cefazolin (n=25), clindamycin (n=17) or vancomycin (n=12) was assayed by high-performance liquid chromatography, with cefaclor as an internal standard, to determine the concentration of antibiotic penetrating into the disc tissue.ResultsIntervertebral disc tissues from patients receiving the positively charged antibiotic clindamycin contained a significantly greater percentage of the antibacterial dose than the tissue from patients receiving negatively charged cefazolin (P<0.0001) and vancomycin, which has a slight positive charge (P<0.0001).ConclusionPositively charged antibiotics appear more appropriate for future studies investigating potential options for the treatment of low-virulence disc infections. [GRAPHICS]