PURPOSE OF THE STUDY Prosthetic joint infection is a feared complication in total hip arthroplasty. The use of antibiotic-impregnated bone cement is the important part of preventive and therapeutic strategies. At present a number of commercial bone cements are available and support of their use by the results of experimental trials and clinical studies has varied. In relation to this issue we studied essential microbiological and pharmacological characteristics of VancogenX in comparison with gentamicin-loaded bone cement used conventionally. MATERIAL AND METHODS Based on a previously described protocol, we tested pellets of four commercial bone cements, namely, Hi-Fatigue G, Palacos R+G, VancogenX, and Paiacos R as a control. Bone cement was prepared in a vacuum-mixing system. The strains used for bacterial load included Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli. Each cement was tested for its antimicrobial and antibiofilm activities and the results were evaluated by standard methods. In addition, we investigated time-related release of gentamicin and vancomycin from the bone cements tested. RESULTS All antibiotic-loaded cement pellets were able to prevent growth of the bacterial strains tested. The bactericidal effect lasted for several days in relation to the bacterial species and cement used, with the exception of S. epidermidis whose growth was inhibited by gentamicin-loaded cement only for one day. The antibiotic-loaded pellets also prevented the formation of a biofilm for 24 hours at least. The major amount of vancomycin (32.915 mg/l) was released from VancogenX to MH medium within 24 hours and the last measureable amount (4.327 mg/l) was recorded at 48 hours after the start of the experiment. In physiological saline the highest level of vancomycin was 139.852 mg/ml measured at 24 hours, and the antibiotic was detectable at a level of 2.334 mg/ml as late as 8 days after the experiment started. Release of gentamicin from VancogenX was as follows: the 24-hour level was higher in MH medium than physiological saline (178 versus 131.4 mg/ml); however, gentamicin was still detectable in physiological saline at 192 hours after the start of the experiment while no gentamicin was found in MH medium after 72 hours. DISCUSSION The antimicrobial effect of VancogenX bone cement was not an unexpected finding since both gentamicin and vancomycin have been used with bone cement for a long time and their combination is optimal in terms of preventing prosthetic joint infection. However, there is a disputable issue of poor release of vancomycin from bone cement. In MH medium we were able to detect the vancomycin released from VancogenX only for two days after the initial rapid elution while its release into physiological saline seemed to be slower but much longer. It is possible that more vancomycin is released from bone cement, but this amount is immediately bound to proteins in the cement vicinity and this process is not detectable by any analytical method. CONCLUSIONS The bone cement VancogenX showed excellent antimicrobial and antibiofilm properties and can be recommended for use in orthopaedic practice. Therapy of prosthetic joint infection is the main indication. Extension of the indication to the prevention of prosthetic joint infection in high-risk patients should be preceded by biomechanical studies demonstrating that the cement is appropriate for long-term implant fixation.

• MeSH
• Bacteriological Techniques * methods   MeSH
• Biofilms * drug effects   MeSH
• Gentamicins therapeutic use   MeSH
• Prosthesis-Related Infections * prevention & control   MeSH
• Bone Cements * therapeutic use   MeSH
• Drug Delivery Systems * MeSH
• Arthroplasty, Replacement, Hip * methods   MeSH
• Vancomycin therapeutic use   MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH

• Keywords
• VancogenX,
• MeSH
• Anti-Bacterial Agents administration & dosage   MeSH
• Biofilms * drug effects   MeSH
• Drug Evaluation MeSH
• Prosthesis-Related Infections drug therapy   prevention & control   MeSH
• Clinical Studies as Topic MeSH
• Bone Cements * pharmacokinetics   pharmacology   MeSH
• Humans MeSH
• Drug Carriers MeSH
• Check Tag
• Humans MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Anti-Bacterial Agents MeSH
• Drug Resistance, Bacterial MeSH
• Infections MeSH
• Drug Resistance, Multiple, Bacterial MeSH
• Orthopedic Procedures MeSH
• Postoperative Complications MeSH
• Accidents MeSH
• Publication type
• Lecture MeSH
• Collected Work MeSH

• Conspectus
• Farmacie. Farmakologie
• NML Fields
• farmacie a farmakologie
• infekční lékařství
• ortopedie
• traumatologie

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• Keywords
• spongioplastika, larvální terapie, VancogenX, PerOssal, Lucilia sericata, Prévotův prut, antibiotický spacer,
• MeSH
• Anti-Bacterial Agents * therapeutic use   MeSH
• Surgical Flaps MeSH
• Chronic Disease MeSH
• Debridement MeSH
• Fluorodeoxyglucose F18 diagnostic use   MeSH
• Gentamicins therapeutic use   MeSH
• Therapy with Helminths MeSH
• Tomography, Emission-Computed, Single-Photon MeSH
• Bone Cements * therapeutic use   MeSH
• Bone Substitutes therapeutic use   MeSH
• Therapeutic Irrigation MeSH
• Drug Delivery Systems methods   MeSH
• Middle Aged MeSH
• Humans MeSH
• Osteomyelitis * diagnosis   drug therapy   surgery   MeSH
• Tomography, X-Ray Computed MeSH
• Polymethyl Methacrylate therapeutic use   MeSH
• Radiopharmaceuticals diagnostic use   MeSH
• Negative-Pressure Wound Therapy MeSH
• Tibia surgery   drug effects   MeSH
• Tomography, Emission-Computed MeSH
• Bone Transplantation * methods   MeSH
• Vancomycin therapeutic use   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Publication type
• Case Reports MeSH

PURPOSE OF THE STUDY Infections of joint replacements represent one of the most serious problems in contemporary orthopedics. The joint infections treatment is usually multimodal and involves various combinations of drug delivery and surgical procedures. The aim of this study was to evaluate and compare the bacteriostatic and bactericidal properties of the most common antibiotic carriers used in orthopedic surgery: bone cements mixed with antibiotic and porous calcium sulfate mixed with antibiotic. MATERIAL AND METHODS Three commercial bone cements (Palacos®, Palacos® R+G, Vancogenx®) and commercial porous sulfate (Stimulan®) were prepared with a known concentration of vancomycin (a glycopeptide antibiotic). Specifically, for the purpose of our study, the testing specimens were prepared to release 0, 1, 2, 4, 8, 16, 32, 64, 128, 256, and 512 mg of vancomycin into 1 liter of solution. The specimens with increasing amount of antibiotic were placed in a separate tubes containing 5 mL of Mueller-Hinton broth inoculated with a suspension (0.1 m, McFarland 1) of the reference strain CCM 4223 Staphylococcus aureus to evaluate their bacteriostatic properties (broth dilution method). After this initial incubation and evaluation of the broth dilution method, an inoculum from each tube was transferred onto blood agar plates. After another 24-hour incubation under the same conditions, we evaluated the bactericidal properties (agar plate method). As many as 132 of independent experiments were performed (4 specimens × 11 concentrations × 3 repetitions = 132). RESULTS The bacteriostatic properties of all investigated samples were excellent, perhaps with the exception of the first bone cement (Palacos®). The sample Palacos® started to exhibit bacteriostatic properties at concentrations ≥ 8 mg/mL, while all other samples (Palacos R+G®, Vancogenx®, and Stimulan®) were bacteriostatic in the whole concentration range starting from 1 mg/mL. The bacteriocidic properties did not show such clear trends, but correlated quite well with different properties of the investigated samples during mixing - the most homogeneous samples seemed to exhibit the best and the most reproducible results. DISCUSSION The reliable and reproducible comparison of ATB carriers is a difficult task. The situation is complicated by high numbers of local antibiotic carriers on the market, numerous antibiotics used, and differences in clinical trials at different laboratories. Simple in vitro testing of bacteriostatic and bacteriocidic properties represents a simple and efficient approach to the problem. CONCLUSIONS The study confirmed that the two most common commercial systems used in the orthopedic surgery (bone cements and porous calcium sulfate) prevent bacterial growth (bacteriostatic effect), but they may not be 100% efficient in complete elimination of bacteria (bacteriocidic effect). The scattered results in the case of bacteriocidic tests seemed to be connected with the homogeneity of ATB dispersion in the systems and with the lower reproducibility of the employed agar plate method. Key words: local release of antibiotics; bone cements; calcium sulfate; antimicrobial susceptibility.

• MeSH
• Agar MeSH
• Anti-Bacterial Agents pharmacology   therapeutic use   MeSH
• Bone Cements pharmacology   therapeutic use   MeSH
• Humans MeSH
• Orthopedic Procedures * MeSH
• Orthopedics * MeSH
• Polymethyl Methacrylate chemistry   MeSH
• Reproducibility of Results MeSH
• Calcium Sulfate MeSH
• Vancomycin pharmacology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

• MeSH
• Antimicrobial Stewardship MeSH
• Antibiotic Prophylaxis MeSH
• Publication type
• Congress MeSH
• Collected Work MeSH

• Conspectus
• Farmacie. Farmakologie
• NML Fields
• mikrobiologie, lékařská mikrobiologie
• farmakoterapie