PJI du to Enterobacter cloacae are rare and often severe. The aim of our study is to define the history of patients with such infections and their outcome.

We conducted a retrospective monocentric study in an orthopedic unit where complex bone and joint infections are supported. From 2011 to 214 we selected patients with E. cloacae PJI based on data from the microbiology laboratory. In their files we collected information on their background, their medical and surgical history, antibiotics they received in the year before infection, the suspected portal of entry, the management and the outcome.

Twelve patients were included, 7 male and 5 female. PJI was located to the hip in 8 cases, the knee in 3 cases and the ankle in one case. The average time between the placing of the first prosthesis and infection was 3 years. Eleven patients had one or more surgery for previous PJI. The average time elapsed since the last surgery was 30 days. Eleven patients had been treated with antibiotic combinations for at least 6 weeks, in the year before E cloacae infection. A portal of entry was identified only two times: urinary tract infection in one patient and catheter-related infection in one patient. Antibiotics the more often prescribed were carbapenems (n = 5) and cefepime (n = 4), each combined with quinolones (n =4) or fosfomycin (n = 3). Two patients required an additional debridement within an average of 18 days. Infectious outcome was favorable in 8 cases (67%) with a median duration of follow-up of 26 months. Two patients had a recurrent infection, one due to Streptococcus oralis and one to Candida albicans. One patient had a relapse of E cloacae infection. One patient died from unknown cause.

PJI infections due to E.cloacae usually occur early after prosthetic surgery, typically in patients with complex surgical history. Despite a high rate of multi-resistance to antibiotics, outcome may be favorable in a large majority of patients.