Implantation of resorbable gentamicin sponges in addition to irrigation and debridement in 34 patients with infection complicating total hip arthroplasty

The novel endolysin XZ.700 effectively treats MRSA biofilms in two biofilm models without showing toxicity on human bone cells in vitro

In this in vitro study the effect of XZ.700, a new endolysin, on methicillin resistant Staphylococcus aureus (MRSA) biofilms grown on titanium was evaluated. Biofilms of S. aureus USA300 were grown statically and under flow, and treatment with XZ.700 was compared with povidone-iodine (PVP-I) and gentamicin. To evaluate the cytotoxic effects of XZ.700 and derived biofilm lysates, human osteocyte-like cells were exposed to biofilm supernatants, and metabolism and proliferation were quantified. XZ.700 showed a significant, concentration dependent reduction in biofilm viability, compared with carrier controls. Metabolism and proliferation of human osteocyte-like cells were not affected by XZ.700 or lysates, unlike PVP-I and gentamicin lysates which significantly inhibited proliferation. Using time-lapse microscopy, rapid biofilm killing and removal was observed for XZ.700. In comparison, PVP-I and gentamicin showed slower biofilm killing, with no apparent biofilm removal. In conclusion, XZ.700 reduced MRSA biofilms, especially under flow condition, without toxicity for surrounding bone cells.

Repurposing of antidepression drug sertraline for antimicrobial activity against Staphylococcus aureus: a potential approach for the treatment of osteomyelitis

We report a potential approach to synthesize the repurposed sertraline drug-loaded hydroxyapatite nanoparticles using eggshell as the calcium source via the in situ precipitation method for the treatment of osteomyelitis.

Indications and Guidelines for Debridement and Implant Retention for Periprosthetic Hip and Knee Infection

PURPOSE OF REVIEW

Prosthetic joint infection is one the most common causes of revision surgery after hip or knee replacement. Debridement and implant retention (DAIR) is one method of treating these infections; however, significant controversy exists. The purpose of our review was to describe current knowledge about indications, intraoperative/postoperative patient management, and outcomes of DAIR.

RECENT FINDINGS

Patient selection affects the success of DAIR. Medical comorbidities, duration of symptoms, and nature of infectious organism all influence outcomes. Intraoperative techniques such as open arthrotomy, extensive debridement, copious irrigation, and exchange of modular parts remain current standards for DAIR. Postoperative administration of antibiotics tailored to operative cultures remains critical. Antibiotic suppression may increase the success of DAIR. DAIR provides reasonable infection eradication between 50 and 80% with improved outcomes in appropriately selected patients. More research is needed on the use of adjuvant therapies intraoperatively and the role of postoperative antibiotic suppression.

Daptomycin-loaded biodegradable thermosensitive hydrogels enhance drug stability and foster bactericidal activity against Staphylococcus aureus

A drug delivery system based on fully biodegradable thermosensitive hydrogels enabling controlled antibiotic release may support the management of implant-associated infections. In this work, the lipopeptide antibiotic daptomycin was encapsulated in hydrogel networks consisting of vinyl sulfonated triblock copolymers of PEG-p(HPMAm-lac_1,2) and thiolated hyaluronic acid. High concentrations of active daptomycin exceeding the minimum biofilm eradicating concentration were sustainably eluted from the biodegradable carrier. The drug release profiles were tailored by varying the degree of substitution (DS) of thiol groups of hyaluronic acid, reaching a plateau level after 200 and 330 h for DS values of 53% and 31%, respectively. The hydrogel polymeric network preserved the structural stability of the loaded antibiotic and retained the calcium-dependent daptomycin activity, showing a noticeable biofilm bactericidal effect against a 24 h-old Staphylococcus aureus biofilm in vitro. The two-component thermosensitive hydrogels demonstrated to be an excellent antibiotic releasing scaffold with potential clinical applications in the management of implant-associated infections.

Outcomes following debridement, antibiotics and implant retention in the management of periprosthetic infections of the hip: a review of cohort studies

AIMS

The aims of the study were to review and analyse the reported series of debridement, antibiotics and implant retention (DAIR) in the management of infected total hip arthroplasties (THAs) to establish the overall success and the influencing factors.

PATIENTS AND METHODS

Using a standardised recognised study protocol, meta-analysis of observational studies in epidemiology guidelines, a comprehensive review and analysis of the literature was performed. The primary outcome measure was the success of treatment. The search strategy and inclusion criteria which involved an assessment of quality yielded 39 articles for analysis, which included 1296 patients.

RESULTS

The proportion of success following DAIR in the management of an infected THA appeared to improve after 2004 with a pooled mean proportion of success of 72.2%. For all reported series, from 1977 onwards, there was improved success with early debridement (< 7 days; 75.7%) and exchange of modular components (77.5%). There was a statistically non-significant improvement if debridement was performed within four weeks of the initial procedure (73.0%).

CONCLUSION

The reported success following DAIR has improved since 2004. The only determinants of outcome which we found were the timing of debridement after the onset of symptoms of infection and the exchange of modular components. Cite this article: Bone Joint J 2017;99-B:1488-66.

Prosthetic Joint Infections and Cost Analysis?

Prosthetic joint infection is a devastating complication of arthroplasty surgery that can lead to debilitating morbidity for the patient and significant expense for the healthcare system. With the continual rise of arthroplasty cases worldwide every year, the revision load for infection is becoming a greater financial burden on healthcare budgets. Prevention of infection has to be the key to reducing this burden. For treatment, it is critical for us to collect quality data that can guide future management strategies to minimise healthcare costs and morbidity / mortality for patients. There has been a management shift in many countries to a less expensive 1-stage strategy and in selective cases to the use of debridement, antibiotics and implant retention. These appear very attractive options on many levels, not least cost. However, with a consensus on the definition of joint infection only clarified in 2011, there is still the need for high quality cost analysis data to be collected on how the use of these different methods could impact the healthcare expenditure of countries around the world. With a projected spend on revision for infection at US$1.62 billion in the US alone, this data is vital and urgently needed.

An update on surgical and antimicrobial therapy for acute periprosthetic joint infection: new challenges for the present and the future

Periprosthetic joint infection (PJI) is a devastating complication that can occur following any arthroplasty procedure. Approximately half of these infections develop within the first year after arthroplasty, mainly in the first 1 to 3 months. These infections are known as early PJI. It is widely accepted that many early PJIs can be successfully managed by debridement, irrigation, and prosthetic retention, followed by a course of biofilm-effective antibiotics (debridement, antibiotics, implant retention procedure), but candidate patients should meet the requirements set down in Zimmerli's algorithm. The best antibiotic regimen for acute PJI treated without implant removal remains uncertain. Rifampin-containing regimens, when feasible, are recommended in gram-positive infections, and fluoroquinolones in gram-negative cases. The duration, dosage, and administration route of antibiotics and the use of combined therapy are matters that requires further clarification, as the current level of evidence is low and most recommendations are based on experimental data, studies in small series, and expert experience.

Is prosthesis retention effective for chronic infections in hip arthroplasties? A systematic literature review

The success rate of prosthesis removal as the standard approach to manage chronic infection in hip arthroplasties (HA) is 80-90 %. The effectiveness of prosthesis retention, with or without surgical debridement, to treat patients with chronic HA infection (symptom duration of more than 4 weeks) has not been well established, whereas this strategy is sometimes used in clinical practice. This study aimed to explore the cumulative incidence of failure of chronic HA infections treated with prosthesis retention, with or without debridement. A systematic literature review was conducted in accordance with the methods described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Studies concerning patients with chronically infected HA treated with prosthesis retention were included. The primary outcome was the cumulative risk of failure. We searched the MEDLINE, Embase, and Cochrane databases up to April 2014. The database searches provided a total of 1,213 studies for potential inclusion in the review. Six relevant studies were finally identified, corresponding to 29 patients included. Their treatments consisted of prosthesis retention with debridement. This strategy failed for 14 out of these 29 patients after a 1-year follow-up. The failure rate of the prosthesis retention approach associated to debridement for chronic infection in HA is 48.3 % in this review. Debridement and prosthesis retention in association with prolonged antimicrobial treatment may be an advantageous alternative to arthroplasty exchange for frail patients. The difficulty in finding relevant studies illustrates the challenges of interpreting the existing literature for the management of chronic prosthetic joint infection (PJI).

Local release of antibiotics for surgical site infection management using high-purity calcium sulfate: an in vitro elution study

BACKGROUND

The aim of this study was to characterize the elution of four antibiotics from pharmaceutical-grade calcium sulfate beads and show that the eluted antibiotics retained efficacy.

METHODS

Calcium sulfate was combined with gentamicin, tobramycin, vancomycin, or rifampicin (ratio: 20 g of calcium sulfate, to 240 mg, 500 mg, 900 mg, and 600 mg of antibiotic, respectively). Three grams of beads were immersed in 4 mL of sterile phosphate-buffered saline (PBS) at 37°C. At each time point (4, 8, 24 h; 2, 7, 14, 28, 42 d), eluates were removed for analysis by liquid chromatography-mass spectrometry. The antimicrobial efficacy of antibiotics combined with calcium sulfate beads after 42 d was tested by a modified Kirby-Bauer disc diffusion assay.

RESULTS

All samples showed a generally exponential decay in the eluted antibiotic concentration. At the first time point, both gentamicin and tobramycin had eluted to a peak concentration of approximately 10,000 mcg/mL. For rifampicin, the peak concentration occurred at 24 h, whereas for vancomycin, it occurred at 48 h. The eluted concentrations exceeded the minimum inhibitory concentration for common periprosthetic joint infection pathogens for the entire span of the 42 study days. Mass spectrometry confirmed all antibiotics were unchanged when eluted from the calcium sulfate carrier. Antimicrobial efficacy was unaltered after 42 d in combination with calcium sulfate at 37°C.

CONCLUSIONS

Pharmaceutical-grade calcium sulfate has the potential for targeted local release of tobramycin, gentamicin, vancomycin, and rifampicin over a clinically meaningful time period.

Treatment of acute periprosthetic infections with prosthesis retention: Review of current concepts

Periprosthetic joint infection (PJI) is a devastating complication after total joint arthroplasty, occurring in approximately 1%-2% of all cases. With growing populations and increasing age, PJI will have a growing effect on health care costs. Many risk factors have been identified that increase the risk of developing PJI, including obesity, immune system deficiencies, malignancy, previous surgery of the same joint and longer operating time. Acute PJI occurs either postoperatively (4 wk to 3 mo after initial arthroplasty, depending on the classification system), or via hematogenous spreading after a period in which the prosthesis had functioned properly. Diagnosis and the choice of treatment are the cornerstones to success. Although different definitions for PJI have been used in the past, most are more or less similar and include the presence of a sinus tract, blood infection values, synovial white blood cell count, signs of infection on histopathological analysis and one or more positive culture results. Debridement, antibiotics and implant retention (DAIR) is the primary treatment for acute PJI, and should be performed as soon as possible after the development of symptoms. Success rates differ, but most studies report success rates of around 60%-80%. Whether single or multiple debridement procedures are more successful remains unclear. The use of local antibiotics in addition to the administration of systemic antibiotic agents is also subject to debate, and its pro’s and con’s should be carefully considered. Systemic treatment, based on culture results, is of importance for all PJI treatments. Additionally, rifampin should be given in Staphylococcal PJIs, unless all foreign material is removed. The most important factors contributing to treatment failure are longer duration of symptoms, a longer time after initial arthroplasty, the need for more debridement procedures, the retention of exchangeable components, and PJI caused by Staphylococcus (aureus or coagulase negative). If DAIR treatment is unsuccessful, the following treatment option should be based on the patient health status and his or her expectations. For the best functional outcome, one- or two-stage revision should be performed after DAIR failure. In conclusion, DAIR is the obvious choice for treatment of acute PJI, with good success rates in selected patients.

Prosthetic joint-associated infections treated with DAIR (debridement, antibiotics, irrigation, and retention): analysis of risk factors and local antibiotic carriers in 91 patients

BACKGROUND AND PURPOSE

For prosthetic joint-associated infection (PJI), a regimen of debridement, antibiotics, irrigation, and retention of the prosthesis (DAIR) is generally accepted for acute infections. Various risk factors associated with treatment success have been described. The use of local antibiotic carriers (beads and sponges) is relatively unknown. We retrospectively analyzed risk factors in a cohort of patients from 3 hospitals, treated with DAIR for PJI.

PATIENTS AND METHODS

91 patients treated with DAIR for hip or knee PJI in 3 Dutch centers between 2004 and 2009 were retrospectively evaluated. The mean follow-up was 3 years. Treatment success was defined as absence of infection after 2 years, with retention of the prosthesis and without the use of suppressive antibiotics.

RESULTS

60 patients (66%) were free of infection at follow-up. Factors associated with treatment failure were: a history of rheumatoid arthritis, late infection (> 2 years after arthroplasty), ESR at presentation above 60 mm/h, and infection caused by coagulase-negative Staphylococcus. Symptom duration of less than 1 week was associated with treatment success. The use of gentamicin sponges was statistically significantly higher in the success group, and the use of beads was higher in the failure group in the univariate analysis, but these differences did not reach significance in the logistic regression analysis. Less surgical procedures were performed in the group treated with sponges than in the group treated with beads.

INTERPRETATION

In the presence of rheumatoid arthritis, duration of symptoms of more than 1 week, ESR above 60 mm/h, late infection (> 2 years after arthroplasty), and coagulase-negative Staphylococcus PJI, the chances of successful DAIR treatment decrease, and other treatment methods should be considered.