Abstract

Chronic osteomyelitis is mostly caused by bacteria such as S. aureus, and is often treated with oral antibiotics or injections to suppress the bacteria. In severe cases, however, surgical treatment using antibiotic beads and metal supports may be required. In these surgeries, bacterial attachment to the metal may lead to biofilm formation and reduce antibiotics’ penetration to the bacteria. Reoperation must be performed to prevent bacterial inflammatory reactions and antibiotic resistance. Thus, in this study, we developed a dual-drug-releasing PCL/sodium-alginate-based 3D-printed scaffold to effectively treat osteomyelitis by removing the biofilm. We proposed an antibiotic-loaded biodegradable polymer scaffold using 3D printing, which was encapsulated by a second antibiotic-containing hydrogel. Then, we successfully established a dual-drug-based scaffold that consisted of a cefazolin (CFZ)-containing polycaprolactone 3D scaffold and a rifampicin (RFP)-loaded alginate hydrogel encapsulating the 3D scaffold. Our scaffold showed a synergistic effect, whereby biofilm formation was inhibited by RFP, which is an external drug, and bacterial activity was inhibited by CFZ, which is an internal drug that increases antibacterial activity. We also confirmed that the dual-drug-based scaffold did not affect the proliferation of human osteoblasts. Our findings suggest that this dual drug delivery system may serve as a new therapeutic treatment for osteomyelitis that overcomes the limitations of individual drugs.

Highlights

  • Staphylococcus constitutes up to two-thirds of the total pathogens in orthopedic implant infections, and is the major causative agent of osteomyelitis, causing inflammatory destruction of bones [1]

  • When S. aureus is identified as the causative strain, a therapeutic antimicrobial agent from among several types of antibiotics—including nafcillin, cefazolin (CFZ), aminopenicillin, vancomycin, and rifampicin (RFP)—is selected based on the results of antibacterial sensitivity testing [2–4]

  • The RFP–alginate layer gradually reduced biofilm formation to approximately 50% over 48 h, regardless of the presence of CFZ within the scaffolds. This was consistent with the absorbance measurement at 590 nm (Figure 4B), and together these results demonstrated that the presence of RFP significantly reduced S. aureus biofilm formation

Read more

Summary

Introduction

Staphylococcus constitutes up to two-thirds of the total pathogens in orthopedic implant infections, and is the major causative agent of osteomyelitis, causing inflammatory destruction of bones [1]. Due to the increasing frequency of S. aureus infections in osteomyelitis, the rapid development and display of multiple antibiotic resistance, and the tendency to progress from acute infections to persistent, chronic, and recurrent infections, this pathogen continues to receive considerable attention [5]. Treatment of these infections is complicated by the formation of bacterial biofilms, which are implicated in most cases of osteomyelitis [5]. Bacterial biofilm infections are problematic because sessile bacteria can withstand host immune responses and are drastically more resistant to antibiotics [5]. The eradication of biofilms requires higher concentrations of antibiotics, increasing the likelihood of multidrug resistance

Objectives
Methods
Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call