Temporal Trends in the Rate of Revision Total Knee Arthroplasty for Prosthetic Joint Infection.

Background: Perioperative practices have been introduced over the last decade to decrease the risk of periprosthetic joint infection (PJI). We sought to determine whether rates of revision total knee arthroplasty (TKA) for PJI decreased during the period 2006-2016. Methods: This observational cohort study used data from the New York Statewide Planning and Research Cooperative System to identify patients undergoing TKA in 2006-2016. Data through 2017 were used to determine if patients underwent revision TKA for PJI (including debridement, antibiotics and implant retention) within 1 year of the primary surgery. A generalized estimating equation model, clustered by hospital, was used to examine the impact of time on likelihood of revision TKA for PJI. Results: In 2006-2016, 233,165 primary TKAs performed were included. Mean age was 66.1 (standard deviation 10.3) years, and 65% were women. Overall, 0.5% of the patients underwent revision TKA for PJI within 1 year of surgery. The generalized estimating equation model showed that for primary TKA performed in 2006-2013, year of surgery did not impact the likelihood of revision TKA for PJI (odds ratio 1.00, 95% confidence interval 0.97-1.03, P = .9221), but that for primary TKA performed in 2014-2016, the likelihood decreased by year (odds ratio 0.76, 95% confidence interval 0.66-0.88, P = .0002). Conclusions: The likelihood of revision TKA for PJI was stable from 2006 to 2013 but declined during the period 2014-2016 across patient and hospital categories. This decline could be due to infection mitigation strategies or other unmeasured factors.

Greater Risk of Periprosthetic Joint Infection Associated with Prolonged Operative Time in Primary Total Knee Arthroplasty: Meta-Analysis of 427,361 Patients.

Background/Objectives: Periprosthetic joint infection (PJI) is a severe complication in total knee arthroplasty (TKA) with catastrophic outcomes. The relationship between prolonged operative times and PJI remains debated. This meta-analysis investigated the link between prolonged operative times and the risk of PJI in primary TKA. Methods: A comprehensive search of the MEDLINE/PubMed, Cochrane Library, and EMBASE databases was conducted to identify studies comparing the incidence of PJI in TKAs with prolonged versus short operative times, as well as those comparing operative times in TKAs with and without PJI. Pooled standardized mean differences (SMD) in operative times between groups with and without PJI or surgical site infections (SSI), including superficial SSIs and PJIs, were analyzed. Additionally, the pooled odds ratios (OR) for PJI in TKAs with operative times exceeding 90 or 120 min were examined. Results: Seventeen studies involving 427,361 patients were included. Significant differences in pooled mean operative times between the infected and non-infected TKA groups were observed (PJI, pooled SMD = 0.38, p < 0.01; SSI, pooled SMD = 0.72, p < 0.01). A higher risk of PJI was noted in surgeries lasting over 90 or 120 min compared to those of shorter duration (90 min, pooled OR = 1.50, p < 0.01; 120 min, pooled OR = 1.56, p < 0.01). Conclusions: An association between prolonged operative time and increased risk of PJI in primary TKA has been established. Strategies for infection prevention should encompass thorough preoperative planning aimed at minimizing factors that contribute to prolonged operative times.

Impact of antibiotic prophylaxis in second-stage surgery in joint prosthesis infection treated with two-stage exchange. A multicenter case-control study.

INTRODUCTION: After two-stage exchange due to prosthetic joint infection (PJI), the new prosthesis carries a high risk of reinfection (RePJI). There isn`t solid evidence regarding the antibiotic prophylaxis in 2nd-stage surgery. The objective of this study is to describe what antibiotic prophylaxis is used in this surgery and evaluate its impact on the risk of developing RePJI. METHODS: Retrospective multicenter case-control study in Spanish hospitals. The study included cases of PJI treated with two-stage exchange and subsequently developed a new infection. For each case, two controls were included, matched by prosthesis location, center, and year of surgery. The prophylaxis regimens were grouped based on their antibacterial spectrum, and we calculated the association between the type of regimen and the development of RePJI using conditional logistic regression, adjusted for possible confounding factors. RESULTS: We included 90 cases from 12 centers, which were compared with 172 controls. The most frequent causative microorganism was Staphylococcus epidermidis with 34 cases (37.8%). Staphylococci were responsible for 50 cases (55.6%), 32 of them (64%) methicillin-resistant. Gram-negative bacilli were involved in 30 cases (33.3%), the most common Pseudomonas aeruginosa. In total, 83 different antibiotic prophylaxis regimens were used in 2nd-stage surgery, the most frequent a single preoperative dose of cefazolin (48 occasions; 18.3%); however, it was most common a combination of a glycopeptide and a beta-lactam with activity against Pseudomonas spp (99 cases, 25.2%). In the adjusted analysis, regimens that included antibiotics with activity against methicillin-resistant staphylococci AND Pseudomonas spp were associated with a significantly lower risk of RePJI (adjusted OR = 0.24; 95% IC: 0.09-0.65). CONCLUSIONS: The lack of standardization in 2nd-satge surgery prophylaxis explains the wide diversity of regimens used in this procedure. The results suggest that antibiotic prophylaxis in this surgery should include an antibiotic with activity against methicillin-resistant staphylococci and Pseudomonas.

Short-term outcomes of a multicentre prospective study using a "visible" polyvinylidene fluoride onlay mesh for the prevention of midline incisional hernia.

INTRODUCTION: Prophylactic meshes in high-risk patients prevent incisional hernias, although there are still some concerns about the best layer to place them in, the type of fixation, the mesh material, the significance of the level of contamination, and surgical complications. We aimed to provide answers to these questions and information about how the implanted material behaves based on its visibility under magnetic resonance imaging (MRI). METHOD: This is a prospective multicentre observational cohort study. Preliminary results from the first 3 months are presented. We included general surgical patients who had at least two risk factors for developing an incisional hernia. Multivariate logistic regression was used. A polyvinylidene fluoride (PVDF) mesh loaded with iron particles was used in an onlay position. MRIs were performed 6 weeks after treatment. RESULTS: Between July 2016 and June 2022, 185 patients were enrolled in the study. Surgery was emergent in 30.3% of cases, contaminated in 10.7% and dirty in 11.8%. A total of 5.6% of cases had postoperative wound infections, with the requirement of stoma being the only significant risk factor (OR = 7.59, p = 0.03). The formation of a seroma at 6 weeks detected by MRI, was associated with body mass index (OR = 1.13, p = 0.02). CONCLUSIONS: The prophylactic use of onlay PVDF mesh in midline laparotomies in high-risk patients was safe and effective in the short term, regardless of the type of surgery or the level of contamination. MRI allowed us to detect asymptomatic seromas during the early process of integration. STUDY REGISTRATION:  This protocol was registered at ClinicalTrials.gov (NCT03105895).

Global research output and highly-cited publications on prosthetic joint infections: A bibliometric analysis (2003-2022).

Backgroundand aims: Prosthetic Joint Infection (PJI) is a serious clinical problem after Arthroplasty. The research field on PJI is emerging, but there is a paucity of information on the most impactful publications on it. This prompted us to conduct a bibliometric analysis of the global research output, from 2003 to 2022, to identify the growth of publications, the key players in this research field and to evaluate the characteristics of highly-cited publications (HCPs) on the PJI. Methods: Publications related to PJI research were identified globally from the Scopus database, using specific keywords, covering the literature from 2003 to 2022. The HCPs were considered those with 100 or more citations. Information on publication year, citation count, funding sources, title, author, journal, country, institution, research area, and strategic keywords were collected from these HCPs. Publication data was imported into Microsoft Excel and analyzed further using VOSviewer and R software. Results: There were 182 HCPs (3.12%), which received a total citation of 124701 (average CPP of 21.41), with the citation range from 100 to 1921. Research articles were the most predominant publications (69.2%), but their average citations per paper (CPP) of 189.78 was lower than that of Review articles (average CPP: 253.17). The USA has been the leading country in terms of total publications (31.58%), and HCPs (36.99%), followed by Switzerland, Spain, UK and China. There were no HCPs from developing countries. J. Parvizi of Thomas Jefferson University, USA (with a total publications of 31 and an average CPP of 315.7), and W. Zimmerli of Basel University, Switzerland (with a TP of 11 and an average CPP of 341.9), were the most productive and impactful authors in PJI global research output. Conclusion: This bibliometric analysis identified the most productive and impactful authors, organizations, countries, and journals in the research of PJI, of the last two decades.

Optimal selection of specimens for metagenomic next-generation sequencing in diagnosing periprosthetic joint infections.

Objective: This study aimed to assess the diagnostic value of metagenomic next-generation sequencing (mNGS) across synovial fluid, prosthetic sonicate fluid, and periprosthetic tissues among patients with periprosthetic joint infection (PJI), intending to optimize specimen selection for mNGS in these patients. Methods: This prospective study involved 61 patients undergoing revision arthroplasty between September 2021 and September 2022 at the First Affiliated Hospital of Zhengzhou University. Among them, 43 cases were diagnosed as PJI, and 18 as aseptic loosening (AL) based on the American Musculoskeletal Infection Society (MSIS) criteria. Preoperative or intraoperative synovial fluid, periprosthetic tissues, and prosthetic sonicate fluid were collected, each divided into two portions for mNGS and culture. Comparative analyses were conducted between the microbiological results and diagnostic efficacy derived from mNGS and culture tests. Furthermore, the variability in mNGS diagnostic efficacy for PJI across different specimen types was assessed. Results: The sensitivity and specificity of mNGS diagnosis was 93% and 94.4% for all types of PJI specimens; the sensitivity and specificity of culture diagnosis was 72.1% and 100%, respectively. The diagnostic sensitivity of mNGS was significantly higher than that of culture (X2 = 6.541, P=0.011), with no statistically significant difference in specificity (X2 = 1.029, P=0.310). The sensitivity of the synovial fluid was 83.7% and the specificity was 94.4%; the sensitivity of the prosthetic sonicate fluid was 90.7% and the specificity was 94.4%; and the sensitivity of the periprosthetic tissue was 81.4% and the specificity was 100%. Notably, the mNGS of prosthetic sonicate fluid displayed a superior pathogen detection rate compared to other specimen types. Conclusion: mNGS can function as a precise diagnostic tool for identifying pathogens in PJI patients using three types of specimens. Due to its superior ability in pathogen identification, prosthetic sonicate fluid can replace synovial fluid and periprosthetic tissue as the optimal sample choice for mNGS.

Does Using Highly Porous Tantalum in Revision Total Hip Arthroplasty Reduce the Rate of Periprosthetic Joint Infection? A Systematic Review and Meta-Analysis.

Background: Studies suggest tantalum (Ta) implants may have inherent antibacterial properties. However, there is no consensus regarding the effectiveness of Ta in preventing periprosthetic joint infection (PJI) after revision total hip arthroplasty (rTHA). Methods: We searched 5 main databases for articles reporting the rate of PJI following rTHA using Ta implants from inception to February 2022. The PJI rates of the Ta group were meta-analyzed, compared with the control group, and represented as relative risks (RRs) in forest plots. Results: We identified 67 eligible studies (28,414 joints) for assessing the prevalence of PJI following rTHA using Ta implants. Among these studies, only 9 compared the Ta implant group with a control group. The overall PJI rate following rTHA using Ta implants was 2.9% (95% confidence interval [CI]: 2.2%-3.8%), while it was 5.7% (95% CI = 4.1%-7.8%) if only septic revisions were considered. Comparing the Ta and control groups showed a significantly lower PJI rate following all-cause rTHA with an RR = 0.80 (95% CI = 0.65-0.98, P < .05). There was a trend toward lower reinfection rates in the Ta group after rTHA in septic cases, although the difference was not statistically significant (RR = 0.75, 95% CI = 0.44-1.29, P = .30). Conclusions: Ta implants are associated with a lower PJI rate following all-cause rTHA but not after septic causes. Despite positive results, the clinical significance of Ta still remains unclear since the PJI rate was only reduced by 20%. Level of Evidence: IV.

How to create by your own a customized hip cement mega-spacer for a hip megaprosthesis two-stage revision surgery after oncologic limb-salvage surgery - Surgical technique and case report.

Managing chronic periprosthetic infections in patients who have undergone limb-salvage surgery following a malignant bone tumor with megaprosthesis often involves a two-stage revision surgery with the use of a cement-spacer. This paper show details the preparation of a self-made intramedullary metal-stabilized mega-cement spacer for patients needing a two-stage revision surgery due to infection after oncologic bone tumor resection and limb-salvage surgery with megaprosthesis and present two clinical cases treated with this technique. The report provides a practical surgical technique to create a cement hip mega-spacer using readily available tools in most orthopedic surgical settings.

Inferior Outcomes for Patients Transferred Between Surgical Stages for Knee Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) in total knee arthroplasty may result in 2-stage revision surgery. There are limited data describing outcomes when the first stage is completed at an outside hospital and the patient is referred to a tertiary center. We hypothesized that patients have greater success when both surgeries occur at a single center. METHODS: There were 25 knee PJI patients who presented with an antibiotic spacer and had a minimum 2-year follow-up who were retrospectively identified at a single tertiary referral center from 2014 to 2021. A cohort matched for age, sex, body mass index, Elixhauser comorbidity measure, spacer type, infectious organism, and year of surgery was established with patients who had both stages completed at the investigating institution. Modified Delphi success criteria of no subsequent surgery or reinfection with any species were compared. RESULTS: The transferred group demonstrated a treatment success of 40% compared to 84% in the continuous group (P < .01). The transferred group was more likely to have an additional procedure between stages (44 versus 8%, P < .01), with a higher number of surgeries after primary total knee arthroplasty (4.8 versus 3.0, P < .01), between stages (1.4 versus 0.2, P < .01), and after second stage (0.8 versus 0.2, P = .03). The transferred group had longer durations between stages (20.1 versus 7.0 weeks, P < .01). CONCLUSION: Patients who have PJIs transferred between stages demonstrated higher treatment failure. Surgeons should consider transfer early with a goal of continuous management by a single institution.

Analysis of risk factors for periprosthetic joint infection after primary total knee arthroplasty and construction of a nomogram prediction model / 中华创伤骨科杂志

Objective:To investigate the risk factors for periprosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) and construct a nomogram model for prediction of such risks.Methods:In this retrospective study, we enrolled 69 patients with PJI after primary TKA (the infection group, n=69) who had been admitted to Department of Orthopedics, Nanjing Jinling Hospital, The First School of Clinical Medicine, Southern Medical University from January 2010 to December 2019. The non-infection group included the patients of the same kind but without postoperative infection during the same period who were matched according to time of admission, age, and gender in a ratio of 1∶3 ( n=207). The data on body mass index, anesthesia method, operation time, preoperative C-reactive protein, preoperative albumin, and comorbid medical conditions were collected from both groups to screen the risk factors for postoperative development of PJI using univariate and multivariate conditional logistic regression analyses. After a nomogram of the risk factors was plotted using R software, the consistency index (C-index) was calculated. The receiver operating characteristic curve, calibration curve, and clinical decision curve were drawn. Results:Multivariate conditional logistic regression analysis showed that preoperative albumin <35 g/L ( OR=7.166, 95% CI: 3.427 to 14.983, P<0.001), operation time >90 min ( OR=3.163, 95% CI: 1.476 to 6.779, P=0.003), diabetes mellitus ( OR=3.966, 95% CI: 1.833 to 8.578, P<0.001), rheumatic diseases ( OR=3.531, 95% CI: 1.362 to 9.156, P=0.009), and chronic lung diseases ( OR=4.734, 95% CI: 1.790 to 12.521, P=0.002) were risk factors for development of PJI after primary TKA. The nomogram constructed with R software visualized the model. The C-index of the nomogram was 0.809 (95% CI: 0.751 to 0.867), indicating a good predictive capability of the model. The calibration curves of the model showed that the nomogram was in good agreement with the actual observations. The decision curves showed that the threshold probabilities of the model ranged from 0.08 to 0.75, providing a good net clinical benefit. Conclusions:Preoperative low albumin, prolonged operation time, diabetes, rheumatic diseases, and chronic lung diseases may be the risk factors for PJI after primary TKA. The nomogram prediction model based on these factors can provide a reference for clinicians to prevent PJI.

The current status and future of knee joint revision surgery / 中华骨科杂志

With enhanced recovery after surgery (ERAS), research and application of knee revision protheses and customized components or prostheses in the past decade, revision of total knee arthroplasty (TKA) is developing rapidly. However, periprosthetic joint infection (PJI) has always been a major clinical challenge. A comprehensive preoperative examination to find any potential infection sites should be conducted. The overall condition of the patients should be improved. Surgeons should evaluate the classification and degree of soft tissue and bone defects comprehensively and carefully select appropriate surgical approaches, bone reconstruction strategies, and revision prostheses to ultimately restore the alignment, stability, and the range of motion of the knee joint. In the future, efforts should be made to build a team of experts for the support of revisions of TKAs, including preoperative planning, 3D printing, surgical techniques, and ERAS. Nevertheless, primary TKAs protocols should always be firmly sticked to, which are a key to a low rate of revision surgeries. Prevention of PJIs and periprosthetic fractures, as well as establishing a high-quality follow-up system are of the same importance.

Analysis of the causes of revision total knee arthroplasty / 中华骨科杂志

Objective:To assess causes for revision total knee arthroplasty (TKA) in China using the data of revision TKA in the past 15 years in our single center andcompare the differences in survival time, operation time and blood loss among different revision reasons.Methods:Data of 337 patients (345 knees) with revision TKAs at our institution from January 2007 to December 2021 (15 years) were retrospectively analyzed. The included population consists of 57 males and 288 females. The causes for first revision TKA were identified and compared according to the time of revision surgery as early (up to 2 years) and late revision (more than 2 years). The reason for revision before 2012 and after 2012 was also compared. Furthermore, the differences of survival time, operation time and blood loss among different revision reasons were compared.Results:The most common reasons for revision of knee joints in 345 cases were periprosthetic infection (133 knees, 38.6%), followed by aseptic loosening (97 knees, 28.1%) and joint instability (35 knees, 10.1%). Early revisions were performed in 171 knees (49.6%), while late revisions were performed in 174 knees (50.4%). Periprosthetic infection (96 knees, 56.1%) and aseptic loosening (86 knees, 49.4%) were the most common reasons for early and late revisions, respectively. There were 59 revisions performed before 2012 and 286 revisions performed after 2012, with periprosthetic infection being the main reason for revision in both groups. The percentage of revisions due to infection decreased from 64.4% before 2012 to 33.2% after 2012, and this difference was statistically significant (χ 2=18.790, P<0.001). The proportion of revisions due to aseptic loosening was 15.3% before 2012, which was significantly lower than the proportion of 30.8% after 2012 (χ 2=5.083, P=0.024). The median survival time of the prostheses in the included patients was 30 months, with shorter survival time observed in patients with stiffness, patellar complications, and periprosthetic infection, and longer survival time observed in patients with polyethylene wear and aseptic loosening. There were significant differences in operation time and blood loss among different reasons for revision ( P<0.001). Conclusion:In our specialized arthroplasty center periprosthesis infection was the most common reason for revision. Periprosthesis infection and aseptic loosening needed to be considered for early or late-stage revision. With the development of technique of total knee arthroplasty, the proportion of periprosthesis infection is decreasing, while the incidence of aseptic loosening is increasing.

The impact of constrained prostheses on the outcomes of two-stage revision for periprosthetic joint infection after total knee arthroplasty / 中华骨科杂志

Objective:To assess the clinical efficacy and infection control outcomes of two-stage revision in managing periprosthetic joint infection (PJI) following primary total knee arthroplasty (TKA) utilizing either a low or high constrained prosthesis.Methods:A retrospective analysis was performed on 40 patients who underwent revision TKA in the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University from February 2019 to February 2022. According to the type of prosthesis selected in primary TKA, they were divided into low constrained prosthesis group and high constrained prosthesis group. There were 28 patients (28 knees) in the low constrained group, including 12 males and 16 females, aged 69.0(63.0, 74.0) years, with a body mass index of 25.18±0.55 kg/m 2. And there were 12 patients (12 knees) in the high-constrained group, including 5 males and 7 females, aged 66.5(65.0, 71.5) years, with a body mass index of 23.94±0.51 kg/m 2. All patients underwent two-stage revision surgery, with RHK used in 1 case and LCCK in 27 cases in the low-constrained prosthesis group. In the high-constrained prosthesis group, 3 patients were treated with RHK, 1 patient with PFC Sigma MBT, and 8 patients with LCCK. The preoperative and postoperative range of motion (ROM), Knee Society score (KSS), and postoperative infection control rate were compared between the two groups. Results:All patients were followed up. The follow-up time was 22.79±8.02 months in the low-constrained prosthesis group and 23.92±7.04 months in the high-constrained prosthesis group, with no significant difference between the two groups ( t=0.426, P=0.680). At the last follow-up, the KSS and ROM in the low-constrained prosthesis group were 77.96±9.74 and 93.48°±7.45°, respectively, significantly higher than 38.93±8.01 and 68.89°±9.44° before the operation ( P<0.05). The KSS score and ROM in the high-constrained prosthesis group were 67.83±8.31 and 80.08°±5.89° at the last follow-up, which were also significantly higher than those before operation (34.25±6.31 and 66.50°±10.48°, P<0.05). There was no significant difference in KSS and ROM between the two groups before operation ( P>0.05), but the KSS score and ROM in the low-constrained prosthesis group were significantly higher than those in the high-constrained prosthesis group at the last follow-up ( P<0.05). Bacterial culture results revealed that the primary infectious agents were coagulase-negative Staphylococcus and Staphylococcus aureus, with an overall infection control rate of 80% (32/40). The infection control rate was 89% (25/28) in the low-constrained prosthesis group and 58% (7/12) in the high-constrained prosthesis group, but the difference between the two groups was not statistically significant (χ 2=3.283, P=0.070). Conclusion:Two-stage revision effectively controls PJI, and the clinical outcomes of two-stage revision for PJI after primary TKA with a high-constrained prosthesis are inferior to those with a low-constrained prosthesis. Further exploration is needed to enhance efficacy.

The role of four-generation Oxford nanopore sequencing technology in searching for pathogenic bacteria in periprosthetic infection / 中华骨科杂志

Objective:To explore the application value of Oxford nanopore technologies (ONT) in the diagnosis and treatment of periprosthetic joint infection (PJI).Methods:A prospective analysis was conducted on 32 patients with PJI admitted to the joint department of Xi'an Honghui Hospital from October 2021 to March 2023, who met the 2018 PJI diagnostic criteria of the American Skeletal Infection Society (MSIS), including 15 males and 17 females with an average age of 63.93±8.93 years. 32 revision patients who did not meet the 2018 MSIS PJI criteria during the same period were collected as controls (non PJI group), including 13 males and 19 females with an average age of 65.53±8.54 years. All patients underwent joint fluid puncture before or during surgery, and the specimens were tested by ONT, metagenomic next generation sequencing (mNGS), and general microbial culture. The receiver operating characteristic (ROC) curves were drawn for both groups, and the sensitivity, specificity, positive predictive value, negative predictive value, and Youden index of the three detection techniques were calculated and compared to evaluate the detection efficiency of different detection methods in PJI.Results:Among the 32 patients with PJI, 30 were positive for ONT, with a total of 30 pathogenic bacteria detected, and the detection time was 22.37±8.36 h. 31 were positive for mNGS, with a total of 33 bacterial species detected, and the detection time was 46.25±9.36 h. 17 were positive for microbial culture, with a total of 8 bacterial species detected, and the detection time was 96.23±15.62 h. Among the 32 patients with non PJI group, 1 was positive for ONT and 5 were positive for mNGS, with a total of 1 and 3 bacterial species detected, respectively. The results of microbial culture were all negative. The detection time and area under the curve (AUC) of ONT and mNGS were 22.37±8.36 h and 0.953[95% CI (0.901, 1.006)], 46.25±9.36 h and 0.906[95% CI (0.835, 0.977)], respectively, which were better than those of microbial culture 96.23±15.62 h and 0.766[95% CI (0.678, 0.853)], and the difference was statistically significant ( P<0.05). The sensitivity of ONT, mNGS, and microbial culture were 0.938, 0.969, and 0.531, respectively, and the specificity was 0.969, 0.844, and 1.000, respectively. The Jordan index was 0.906, 0.813, and 0.531, respectively. Conclusion:ONT testing has higher diagnostic efficacy than mNGS and microbial culture in the diagnosis of PJI, and also has advantages in detection time. It also suggests that some PJI are not caused by a single microbial infection.

Comparison of Surgical Procedures in the Treatment of Hip Periprosthetic Infection.

Objective The present study aimed to compare the cure rate recovery time and Merle d'Aubigné-Postel functional (MAPF) score after single-stage surgery (C1T) or two-stage surgery (C2T) to treat prosthetic infections of the hip considering sociodemographic and clinical features of the patients. Materials and Methods The present retrospective study occurred in a single center from 2011 to 2014 with 37 studied cases including 26 treated with C1T and 11 with C2T. We compared the cure rate recovery time and MAPF score in the two groups as well as the sociodemographic and clinical features of the patients. We also considered surgical complications and the most common infectious agents. Results The C1T group had a faster functional recovery than the C2T group but there were no significant differences in the cure rate surgical complications or MAPF score. However C1T group patients were significantly younger which may have influenced the outcomes. Staphylococcus spp. was the most common infectious agent (62%). Conclusion Although C2T appears superior regarding infection cure C1T may be preferable for faster functional recovery. However it is critical to consider individual patient characteristics when choosing treatment. Further research with a larger sample size is required to confirm these results.

Increased recognition of Q fever aortitis as a chronic manifestation of Q fever in tropical North Queensland, Australia.

Aortitis is a life-threatening, manifestation of chronic Q fever. We report a series of 5 patients with Q fever aortitis who have presented to our hospital in tropical Australia since 2019. All diagnoses were confirmed with polymerase chain reaction (PCR) testing of aortic tissue. Only one had a previous diagnosis of acute Q fever, and none had classical high-risk exposures that might increase clinical suspicion for the infection. All patients underwent surgery: one died and 3 had significant complications. Q fever aortitis may be underdiagnosed; clinicians should consider testing for Coxiella burnetii in people with aortic pathology in endemic areas.

Comparison of Surgical Procedures in the Treatment of Hip Periprosthetic Infection / Comparação entre procedimentos cirúrgicos no tratamento da infecção de prótese do quadril

Abstract Objective The present study aimed to compare the cure rate recovery time and Merle d'Aubigné-Postel functional (MAPF) score after single-stage surgery (C1T) or two-stage surgery (C2T) to treat prosthetic infections of the hip considering sociodemographic and clinical features of the patients. Materials and Methods The present retrospective study occurred in a single center from 2011 to 2014 with 37 studied cases including 26 treated with C1T and 11 with C2T. We compared the cure rate recovery time and MAPF score in the two groups as well as the sociodemographic and clinical features of the patients. We also considered surgical complications and the most common infectious agents. Results The C1T group had a faster functional recovery than the C2T group but there were no significant differences in the cure rate surgical complications or MAPF score. However C1T group patients were significantly younger which may have influenced the outcomes. Staphylococcus spp. was the most common infectious agent (62%). Conclusion Although C2T appears superior regarding infection cure C1T may be preferable for faster functional recovery. However it is critical to consider individual patient characteristics when choosing treatment. Further research with a larger sample size is required to confirm these results.

Resumo Objetivo Comparar a taxa de cura, o tempo de recuperação e a pontuação na escala funcional de Merle d'Aubigné-Postel (EFMA) entre a cirurgia em tempo único (C1T) e a cirurgia em dois tempos (C2T) no tratamento de infecções protéticas do quadril, considerando as características sociodemográficas e clínicas dos pacientes. Materiais e Métodos Foi realizado um estudo retrospectivo num único centro, entre 2011 e 2014, com um total de 37 casos estudados, sendo 26 tratados com C1T e 11 com C2T. Foram comparadas a taxa de cura, o tempo de recuperação e a pontuação EFMA entre os dois grupos, bem como as características sociodemográficas e clínicas dos pacientes. Foram também consideradas as complicações cirúrgicas e o agente infeccioso mais comum. Resultados O grupo C1T teve uma recuperação funcional mais rápida do que o grupo C2T, mas não houve diferenças significativas na taxa de cura, nas complicações cirúrgicas ou na pontuação EFMA. No entanto, o grupo C1T era significativamente mais jovem, o que pode ter influenciado os resultados. Staphylococcus spp. foi o agente infeccioso mais comum (62%). Conclusão Embora a C2T pareça ser superior em termos de cura de infecção, a C1T pode ser preferível para uma recuperação funcional mais rápida. No entanto, as características individuais dos pacientes devem ser consideradas na escolha do tratamento. São necessárias mais pesquisas com um tamanho de amostra maior para confirmar estes resultados.

Impact of Bundled Intervention on Outcomes of Patients Undergoing Clean Orthopedic Surgeries With Hardware Implants: Small Prospective Randomized Controlled Trial.

Background: Prosthesis-related infections (PRIs) and surgical site infections (SSIs) remain one of the most devastating complications among patients undergoing clean orthopedic surgeries. Prevention strategies are critical to reduce infection rates in orthopedic surgeries. The current study aimed to determine the effectiveness of a set of evidence-based practices (bundled intervention) in reducing the incidence of PRIs and SSIs among patients undergoing clean orthopedic surgeries with hardware implants. Patients and Methods: A prospective, interventional randomized controlled trial was conducted for a period of three years. A total of 597 patients were enrolled, and depending on their Staphylococcus aureus carrier status were categorized into carrier group (n = 98) and non-carrier group (n = 499). Only carrier group patients were analyzed for effectiveness of bundled interventions, after being randomly assigned to two subgroups: interventional carrier group (ICG; n = 50) and non-interventional carrier group (NICG; n = 48). Results: Of the 597 patients, 98 (16.4%) were colonized with Staphylococcus aureus, among whom 9 (19.4%) had methicillin resistance. During follow-up, overall infection rate of 1.1% was observed (PRI, 0.3%; SSI, 0.8%). There was no case of PRI/SSI in the ICG. However, in the NICG, one patient developed SSI because of methicillin-resistant Staphylococcus aureus. An endogenous source of infection was demonstrated by pulsed field gel electrophoresis (PFGE). The SSI rate was higher in the NICG (p = 0.002). In the non-carrier group (n = 499), SSIs/PRIs occurred among 1.2% of the patients, because of organisms other than Staphylococcus aureus. Conclusions: Benefit of bundle intervention approach could be demonstrated. Further studies assessing the effectiveness of the individual components of the bundle can inform clinical practice greatly.

Microbiological Profile of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries.

Objective We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital. Methods The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria. Results Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria. Cultures were monomicrobial in 79% and polymicrobial in 21% of cases. The most frequent bacterium in microbiological tissue and synovial fluid cultures was Staphylococcus aureus , observed in 26% of PJI patients. Periprosthetic joint infection with negative cultures occurred in 23% of patients. Conclusion Our results show the following: i) a high prevalence of Staphylococcus as an etiological agent for knee PJI; ii) a high incidence of polymicrobial infections in early infections; iii) the occurrence of PJI with negative cultures in approximately one fourth of the subjects.

Thermal susceptibility and antibiotic synergism of methicillin-resistant Staphylococcus aureus biofilms.

Methicillin-Resistant Staphylococcus aureus (MRSA) biofilms are among the most dangerous infections on medical implants, typically requiring surgical explantation and replacement. This study investigated the thermal susceptibility of MRSA biofilms to thermal shocks from 60 to 80 °C for 1-30 min as well as the effect of various antibiotics (most notably methicillin) on thermal mitigation. Pre- and post-shock exposure to three different classes of antibiotics (ciprofloxacin, tobramycin, and methicillin) at concentrations ranging from 0.25 to 128 µg mL-1 were investigated. MRSA biofilms exhibited thermal susceptibility comparable to other common nosocomial pathogens, such as Pseudomonas aeruginosa, though with greater variability. Exposure to antibiotics of any class significantly decreased the degree of thermal shock required for reliable mitigation, including at subclinical concentration. These combined treatments reduced biofilm population more than the sum of thermal and chemical treatments alone, demonstrating synergism, while also indicating a critical population drop of ∼4.5 log10 beyond which the biofilms typically became non-viable.