Post-Laminectomy Wound Infections: Colonized Seromas Mimicking Wound Infections

Objective: Post-operative laminectomy wounds are frequently accompanied by seromas. Post-operative wound drainage may be colonized or infected. The differentiation of wound colonization from infection is difficult for non-infectious disease physicians. Methods: External chart reviewers classified 31/1531 laminectomies (over three years) as post-operative wound infections. We re-evaluated these cases using infectious disease criteria, i.e., while pathogens may be cultured from both colonized and infected wounds, only wound infections have a purulent discharge with abundant white blood cells (WBCs) on Gram stain. Colonized wounds have positive wound cultures but no/few WBCs on Gram stain. Results: We found only 11/31 actual wound infections, the remainder were not bona fide wound infections, but were colonized seromas. Conclusion: Post-laminectomy colonized seromas that are culture positive for one or more organisms often mimic wound infections. In the era of public reporting of nosocomial infections, it is important that external reviewers differentiate colonization from infection to provide regulatory agencies with accurate data.