In vitro susceptibility of Staphylococcus aureus and Staphylococcus epidermidis isolated from prosthetic joint infections

Abstract

Prosthetic joint infections (PJI) are severe complications in Orthopedics, with Staphylococcus aureus and Staphylococcus epidermidis being the most commonly isolated pathogens. The variable antimicrobial susceptibility found in these microorganisms, along with the increasing number of methicillin-resistant strains, increases the difficulty of antibiotic selection and makes it necessary to perform individual susceptibility studies to select the optimal antibiotic treatment. The aim of this study was to evaluate the in vitro susceptibility pattern of 35 clinical strains isolated from PJI (17 S. aureus and 18 S. epidermidis) against rifampin, vancomycin, tygecicline, clindamycin, cotrimoxazole, cloxacillin, ciprofloxacin, daptomycin and fosfomycin. In vitro susceptibility assays were performed using the broth microdilution method and agar dilution for fosfomycin. MBC was also determined. Tygecicline and daptomycin showed the highest antimicrobial activity with low MIC 90 values, and no resistant strains were detected. On the other hand, ciprofloxacin and cloxacillin exhibited a poor antimicrobial effect with a high percentage of nonsusceptible strains in both species. Bactericidal activity rates revealed the bacteriostatic behavior of rifampin, tygecicline, cotrimoxazole, fosfomycin and clindamycin, whereas vancomycin and cloxacillin showed species-and strain-dependent behavior. Daptomycin and ciprofloxacin were observed to be efficient bactericidal agents against the tested strains. According to our data, rifampin, tigecycline, daptomycin and fosfomycin showed high in vitro activity against most staphylococcal strains isolated from the PJIs tested, although daptomycin seems to be the best alternative to vancomycin therapy.

Rifamycin Derivatives Are Effective Against Staphylococcal Biofilms In Vitro and Elutable From PMMA

“…1 [Supplemental materials are available with the online version of CORR 1 .]) [11,13,39]. Briefly, bacteria (1 9 10 6 CFU/mL) were added to individual wells of the MBEC plates and incubated overnight at 37°C with shaking at 150 rpm (VWR, Radnor, PA, USA).…”

“…Rifampin primarily functions by inhibiting bacterial transcription; however, its excellent diffusive properties combined with activity that is independent of bacterial division allows for activity against biofilms [18,59]. There are numerous in vitro, in vivo, and clinical studies that support the use of rifampin combination antimicrobial therapy for the treatment of staphylococcal bone and joint infections [6,12,19,21,23,39]. Because of the rapid emergence of staphylococcal resistance to rifampin associated with monotherapy, combination antimicrobial therapies, including a nonrifamycin agent, have been recommended by the Infectious Diseases Society of America for bone and joint infections [35].…”

Longitudinal Model of Periprosthetic Joint Infection in the Rat

“…The presence of implants was shown to drastically increase the risk of establishing an infection . The majority of PJIs occur acutely within 3 months of the index surgery and the main causative microorganisms are Staphylococci . Here, we report our design and evaluation of a novel PJI model in rats incorporating clinically relevant materials (a UHMWPE plug and a Ti6Al4V tibial screw), and clinically relevant bacteria (a methicillin‐sensitive Staphylococcus aureus [MSSA]).…”

Sonication of Abdominal Drains: Clinical Implications of Quantitative Cultures for the Diagnosis of Surgical Site Infection

“…Several publications have appeared in recent years documenting the incidence and prevalence of infection-related complications in the peritoneal cavity or other locations having an implanted biomaterial [2][3][4][5][6]. A causal relation between the use of surgical drains and surgical site infections (SSI) has not been clearly established in the literature, and in recent years, prophylactic drainage of the peritoneal cavity has become less popular [7].…”

“…The species and the number of colony forming units (CFU) detected in cultures have been evaluated in order to discriminate between contamination and true infection. We have also established a relation between the microbiological results and true SSI related to drains in an intra-abdominal surgery practice using a methodology with proved usefulness in the diagnosis of other kind of implantrelated infections [2][3][4][5][6].…”