Prosthetic joint infection caused by gram-negative organisms.

Traditionally, periprosthetic joint infections (PJIs) due to gram-negative organisms are considered more difficult to manage; however, little literature exists with regard to outcome of PJI caused by gram-negative organisms. We identified 277 patients with 282 culture-positive PJI receiving surgical treatment. Thirty-one joints were treated for gram-negative PJI. The gram-negative group was then compared with the gram-positive and polymicrobial PJI. A single debridement and retention of prosthesis were successful in 70% (7/10) of isolated gram negative compared with 33.3% (13/39) of methicillin-sensitive gram positive, 48.9% (23/47) of methicillin-resistant gram positive, and 57.1% (4/7) of polymicrobial. Of those patients undergoing a planned 2-stage exchange, a successful reimplantation was performed in 52% (12/23) of gram-negative, 51% (52/103) of methicillin-resistant gram-positive, 69% (65/94) of methicillin-sensitive gram-positive, and 0% (0/8) of polymicrobial PJI cases. These results indicate that PJI due to gram-negative pathogens, although less common, is difficult to treat and is associated with limited success.