Low rate of infection control in enterococcal periprosthetic joint infections.

Background: Enterococcal periprosthetic joint infections (PJIs) are rare after joint arthroplasty. These cases are usually reported in series of PJIs caused by other pathogens. Because few studies have focused only on enterococcal PJIs, management and control of infection of these cases have not yet been well defined.

Questions/purposes: We asked (1) what is the proportion of enterococcal PJI in our institutes; and (2) what is the rate of infection control in these cases?

Methods: We respectively identified 22 and 14 joints with monomicrobial and polymicrobial PJI, respectively, caused by enterococcus. The diagnosis of PJI was made based on the presence of sinus tract or two positive intraoperative cultures. PJI was also considered in the presence of one positive intraoperative culture and abnormal serology. We determined the proportion of enterococcal PJI and management and control of infection in these cases. Minimum followup was 1.5 years (mean, 3.2 years).

Results: The proportion of monomicrobial enterococcal PJI was 2.3% (22 of 955 cases of PJI). Mean number of surgeries was two (range, 1-4). Initial irrigation and débridement was performed in 10 joints and eight patients needed reoperation. Seven of the 16 joints were initially managed using two-stage exchange arthroplasty and did not need further operation. Six patients had a definitive resection arthroplasty. Salvage surgeries (fusion and above-knee amputation) were performed in three cases (8%). The infection was ultimately controlled in 32 of the 36 patients.

Conclusions: Management of enterococcal PJI is challenging and multiple operations may need to be performed to control the infection.

Level Of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.