ASB was an independent risk factor for PJI, particularly that due to gram-negative microorganisms. Preoperative antibiotic treatment did not show any benefit and cannot be recommended.

The aim of our study was to evaluate the outcome of acute prosthetic joint infections (PJIs) due to gram-negative bacilli (GNB) treated without implant removal. Patients with an acute PJI due to GNB diagnosed from 2000 to 2007 were prospectively registered. Demographics, comorbidity, type of implant, microbiology data, surgical treatment, antimicrobial therapy, and outcome were recorded. Classification and regression tree analysis, the Kaplan-Meier survival method, and the Cox regression model were applied. Forty-seven patients were included. The mean age was 70.7 years, and there were 15 hip prostheses and 32 knee prostheses. The median number of days from the time of arthroplasty was 20. The most frequent pathogens were members of the Enterobacteriaceae family in 41 cases and Pseudomonas spp. in 20 cases. Among the Enterobacteriaceae, 14 were resistant to ciprofloxacin, while all Pseudomonas aeruginosa isolates were susceptible to ciprofloxacin. Acute postoperative prosthetic joint infection (PJI) is an uncommon but severe complication after joint arthroplasty. The infection rate is 1 to 3%, and the most frequently isolated microorganisms are gram-positive cocci, including Staphylococcus aureus, coagulase-negative staphylococci, and Streptococcus spp. (12). However, it is of note that gram-negative bacilli (GNB) are isolated in 10% of cases of PJIs, and these infections are frequently polymicrobial (9).The rate of success achieved by treatment with open debridement without implant removal and a prolonged course of antibiotics for staphylococcal acute PJIs is higher than 75% (2, 13, 17). However, there has been little experience with the use of the same surgical and antibiotic treatment for infections due to GNB (3,8). In addition, a major concern associated with PJIs due to GNB is the emergence of strains resistant to many antibiotics and the lack of alternative treatments (15).The aims of the present study were to review our experience with the treatment of acute PJIs due to GNB by the use of open debridement and retention of the implant, followed by antibiotic treatment, and to analyze those factors associated with the outcome. MATERIALS AND METHODSFrom January 2000 to December 2007, all patients with a PJI (hip hemiarthroplasty, total hip and knee arthroplasty) were prospectively registered in a database and the cases were retrospectively reviewed. All patients were treated in the bone and joint infection unit of the same hospital, which includes orthopedic surgeons and infectious disease specialists. Relevant information about each patient's demographics, comorbidity, type of implant (hip or knee prosthesis), clinical manifestations, leukocyte count, C-reactive protein (CRP) concentration at the time of admission for infection, surgical treatment, the microorganism isolated, antimicrobial therapy, and outcome were recorded. In the present study, only those cases with an acute, mono-or polymicrobial PJI due to GNB were included.In the present study, an acute PJI due to GNB was defined by the presence of loc...

One-stage and two-stage revision strategies are the two main options for treating established chronic peri-prosthetic joint infection (PJI) of the hip; however, there is uncertainty regarding which is the best treatment option. We aimed to compare the risk of re-infection between the two revision strategies using pooled individual participant data (IPD). Observational cohort studies with PJI of the hip treated exclusively by one- or two-stage revision and reporting re-infection outcomes were retrieved by searching MEDLINE, EMBASE, Web of Science, The Cochrane Library, and the WHO International Clinical Trials Registry Platform; as well as email contact with investigators. We analysed IPD of 1856 participants with PJI of the hip from 44 cohorts across four continents. The primary outcome was re-infection (recurrence of infection by the same organism(s) and/or re-infection with a new organism(s)). Hazard ratios (HRs) for re-infection were calculated using Cox proportional frailty hazards models. After a median follow-up of 3.7 years, 222 re-infections were recorded. Re-infection rates per 1000 person-years of follow-up were 16.8 (95% CI 13.6–20.7) and 32.3 (95% CI 27.3–38.3) for one-stage and two-stage strategies respectively. The age- and sex-adjusted HR of re-infection for two-stage revision was 1.70 (0.58–5.00) when compared with one-stage revision. The association remained consistently absent after further adjustment for potential confounders. The HRs did not vary importantly in clinically relevant subgroups. Analysis of pooled individual patient data suggest that a one-stage revision strategy may be as effective as a two-stage revision strategy in treating PJI of the hip.Electronic supplementary materialThe online version of this article (10.1007/s10654-018-0377-9) contains supplementary material, which is available to authorized users.