Abstract
Aim
Infection is one of the worst complications following total joint arthroplasty, which is often associated with significant morbidity and increased medical costs. Although Gram–positive bacteria remains the most prevalent causative agents, an increase in prosthetic joint infections (PJI) due to gram-negative bacteria (GNB) has been reported. Additionally, the emergence of multidrug resistant resistance (MDR) in GNB impacts the therapeutic options and may increase the rate of treatment failure and drug toxicity adverse effects due the prescription of harmful and toxics antimicrobial schemes. The purpose of the present study was to describe the predisposing factors associated to PJI caused by MDR-GNB in a specialized orthopedic reference hospital in Brazil from 2014 through 2018.
Method
Retrospective case-control analysis of patients treated for MDR-GNB PJI over a four-year period (2014–2018). Data were collected from medical, surgical and laboratory records. PJI were defined according the criteria of MSIS. MDR was defined as non-susceptibility to at least one agent in three or more antimicrobial categories. Patients with prosthetic infection with at least two positive tissue cultures for MDR-GNB were selected. Univariate and multivariate logistic regression models were used to determine the independent risk factors associated with MDR-GNB PJI. Controls: patients with PJI with at least two positive tissue culture for non MDR- GNB
Results
A total of 104 patients were selected, 59 patients in the MDR-GNB PJI group and 44 in the control. Patients with MDR-GNB PJI were elderly (mean age of 68.36), distribution among sex was similar (49.2% female and 50.8% male) and 72.3% had one or more comorbidities. Most frequently identified comorbidities were diabetes (10.2%), malnutrition (5.5%), hypertension (4.7 %) and obesity (3.9%). Hip replacement accounted for 91.5% of the cases and 59.3% were revision arthroplasty. The mean time between the placement of the prothesis and the onset of PJI signs and symptoms was 438 days. In the univariate regression, the significant risk factors for MDR-GNB PJI were revision arthroplasty, alcoholism, nonelective arthroplasty, prior antimicrobial use, presence of concomitant infection and blood transfusion. However, in the multivariate analysis, prior use of antimicrobials (OR 9.31, CI95% 3.02–28.64) and the nonelective arthroplasty (OR 6.29, CI95% 1.75–22.6) remained as independent risk factors for MDR-GNB PJI
Conclusions
Previous use of antimicrobial and nonelective arthroplasty are important risk factors for PJI by GNB MDR.
