Wenbo Li

Wu B, et al. Clin Orthop Surg. 2026 ;18:e37. https://doi.org/10.4055/cios25110

Objective: Antibiotic exposure affects pathogen detection in periprosthetic joint infection (PJI). This study evaluated the impact of antibiotic duration before sampling on the diagnostic performance of microbiological cultures and metagenomic next-generation sequencing (mNGS). Methods: We conducted a retrospective analysis of 153 patients with PJI treated at our center between January 2013 and March 2024. Patients who had discontinued antibiotics for at least 7 days before sampling and those with no history of antibiotic use were classified into the antibiotic-withdrawal group (AWD group). Based on the duration of antibiotic exposure, those who received antibiotics for ≤ 7 days before sampling was assigned to the short-term antibiotic group (STA group), while those with > 7 days of continuous antibiotic use were included in the long-term antibiotic group (LTA group). By comparing microbiological culture and mNGS results across these groups, we analyzed how antibiotic duration before sampling affects etiological diagnosis in PJI patients. Results: In the AWD group, microbial culture positivity (86.3%, 44/51) was comparable to mNGS (92.2%, 47/51; P=0.338). However, mNGS demonstrated superior positivity rates in both the STA (86.7% vs 70.0%, P=0.027) and LTA groups (76.2% vs 54.8%, P=0.039). Prolonged antibiotic use (> 7 days) markedly reduced culture positivity (86.3% to 54.8%, P=0.001), whereas the decline in mNGS sensitivity was smaller (92.2% to 76.2%, P=0.032), indicating its greater resistance to antibiotic effects. Among culture-negative PJI cases, mNGS maintained robust diagnostic performance across all groups (CN-AWD: 57.1%; CN-STA: 66.7%; CN-LTA: 57.9%), with no significant differences observed. Conclusion: Antibiotic use before sampling significantly impacts PJI pathogen detection. We recommend either: (1) sampling after ≥ 7 days without antibiotics, or (2) for patients on prolonged antibiotics (> 7 days), combining microbial culture with routine mNGS to improve diagnostic accuracy.

Objective Debridement, antibiotics, and implant retention (DAIR) is a widely used surgical approach for managing acute prosthetic joint infection (PJI) following knee arthroplasty (KA). However, limited studies have explored its application across different KA types. This study aims to compare the clinical outcomes of DAIR in acute PJI following unicompartmental knee arthroplasty (UKA) versus total knee arthroplasty (TKA), with a focus on microbial profiles, treatment characteristics, and patient outcomes. Methods We retrospectively reviewed clinical data from 67 consecutive patients diagnosed with acute PJI, as defined by the Musculoskeletal Infection Society (MSIS) criteria, who underwent DAIR at our institution between January 2016 and April 2023. Patients were categorized into two groups based on the type of primary arthroplasty: 51 in the TKA-DAIR group and 16 in the UKA-DAIR group. Comparative analyses included pre- and postoperative serological inflammatory markers, microbiological findings, knee functional outcomes, and infection recurrence rates. Results Coagulase-negative staphylococci were the most frequently isolated organisms in both the TKA-DAIR (37.3%) and UKA-DAIR (43.8%) groups. On postoperative day one, ESR and CRP levels showed no significant differences between groups. However, by postoperative day three, the UKA-DAIR group exhibited significantly lower ESR (P = 0.005) and CRP (P = 0.007) levels, a trend that persisted through day five (ESR, P = 0.014; CRP, P = 0.015). At two year follow-up, there were no significant differences between groups in HSS knee scores (P = 0.107), VAS pain scores (P = 0.531), or range of motion (ROM; P = 0.128). Notably, Kaplan-Meier survival analysis demonstrated a significantly lower infection recurrence rate in the UKA-DAIR group over the two year follow-up period (P = 0.041). Conclusion In cases of acute PJI following UKA, where MRI confirms that the contralateral compartment remains uninvolved and the causative pathogen is clearly identified, DAIR yields superior clinical outcomes compared to TKA. This may be attributed to the reduced prosthetic surface area in UKA and the retention of native cartilage, which may serve as an effective barrier against infection. Based on these findings, we recommend DAIR as the preferred treatment strategy for acute UKA PJI under these conditions.

Objectives: The purpose of this study was to evaluate the impact of adjunctive rifampicin therapy on the outcomes of prosthesis retention versus removal in patients with staphylococcal prosthetic joint infection (PJI) undergoing antibacterial treatment.Methods: A retrospective study was conducted on 227 patients diagnosed with Staphylococcal PJI from March 2014 to September 2023 who underwent debridement, antibiotics, and implant retention (DAIR) or explantation and revision surgery. Based on antimicrobial susceptibility testing, we used an effective baseline antibiotic regimen. We defined the combination of this regimen with rifampicin as the “rifampicin treatment group” and the regimen without rifampicin as the “non-rifampicin treatment group”.Results: A total of 79 patients were included in the rifampin treatment group and 148 in the non-rifampin treatment group. There was no significant difference in the remission rate of PJI between the rifampin treatment group and the non-rifampin treatment group (79.75% vs 73.65%, p = 0.083). Additionally, Kaplan-Meier survival curve analysis showed no statistically significant difference between the two groups (p = 0.509). However, the incidence of drug-related adverse events was significantly higher in the rifampin treatment group compared to the non-rifampin treatment group (31.65% vs 8.78%, p < 0.001). There were no significant difference in treatment success rates between the use and non-use of rifampin in DAIR, one-stage revision, or two-stage revision, as well as in hip or knee joints. Binary logistic regression analysis identified diabetes and active smoking as independent significant risk factors for treatment failure, while rifampin was not an independent risk factor affecting the outcome.Conclusion: The study has not demonstrated that the standard antibiotic regimen combined with rifampin has a significant effect on the efficacy of retaining or removing prostheses in staphylococcal PJI, but rather increases drug-related adverse events. Standard surgical procedures, accurate pathogen diagnosis, and treatment are particularly crucial in the management of PJI.

Objectives: Prosthetic joint infection (PJI) caused by Mycoplasma infection is relatively rare in clinical practice; all cases are primarily reported as individual case reports, and the characteristics of PJI induced by Mycoplasma infection have not been clearly studied. This case–control study was designed to systematically compare demographic profiles, clinical histories, diagnostic modalities, and therapeutic outcomes between Mycoplasma PJI and conventional bacterial PJI through retrospective analysis.Methods: This retrospective single‐center study included 6 cases of simplex Mycoplasma PJI, 4 cases of mixed Mycoplasma PJI, 33 cases of Staphylococcus aureus , and 21 cases of Staphylococcus epidermidis infection from January 1, 2017 to January 1, 2024. Perioperative inflammatory markers, pathogen cultures, metagenomic next‐generation sequencing (mNGS) results, history of invasive urinary catheterization, clinical presentation, treatment, and rate of treatment success were recorded and analyzed for the four groups. Continuous variables were compared two‐by‐two between the four groups using independent t‐tests or the Mann–Whitney U test based on the distribution of the data. The categorical variables were compared using the chi‐square test or Fisher's exact test.Results: The proportion of invasive urinary catheterization history in the mixed versus simplex Mycoplasma group was significantly higher than that in the Staphylococcus aureus and Staphylococcus epidermidis control groups (p < 0.05). Routine microbial culture positivity was significantly lower in the mixed versus simplex Mycoplasma group than in the control group (p < 0.01), but positive results for Mycoplasma can be detected by mNGS. Of note, one patient in the simplex Mycoplasma group was cured with targeted antibiotic‐only therapy and avoided surgery. There was no statistically significant difference in cure rates between the mixed and simplex Mycoplasma groups and the Staphylococcus aureus and Staphylococcus epidermidis control groups (p = 1.000).Conclusion: Prior invasive urinary catheterization represents a significant risk factor for Mycoplasma PJI. The synergistic use of mNGS, optimized culture methods, and 16S rRNA PCR enables early detection of Mycoplasma. This multimodal diagnostic approach significantly enhances pathogen identification accuracy, minimizes diagnostic oversights, and provides essential guidance for effective therapeutic intervention.

Aims: This study aimed to assess whether the clinical outcomes of one-stage revision surgery for chronic knee periprosthetic joint infection (kPJI), guided by precision pathogen diagnosis strategies, are non-inferior to those of conventional two-stage revision surgery. Methods: A retrospective analysis was conducted on chronic kPJI patients who underwent precision pathogen detection and revision arthroplasty at the First Affiliated Hospital of Fujian Medical University between January 2016 and September 2022. Clinical characteristics, pathogen detection rates, targeted antibiotic therapy, reinfection rates, and functional outcomes were compared between patients who underwent one-stage and two-stage revision surgeries. Results: Thirty patients who underwent one-stage revision surgery with pathogen detection through precision pathogen diagnosis strategies were included in this study and were matched with 30 patients who received two-stage revision surgery via propensity score matching (PSM). The baseline clinical characteristics did not significantly differ between the two groups. Utilizing our optimized pathogen detection protocol, successful pathogen identification was achieved in all cases across both groups. The median duration of intravenous antibiotic administration in the one-stage revision cohort was 16.5 (8.5,23.0) days, followed by a 6-week course of sequential oral antibiotics. Both the one-stage and two-stage revision groups had 3 cases of reinfection each, with no statistically significant difference in success rates between the groups (P > 0.999). Furthermore, no significant differences were found in the range of motion (ROM) (P = 0.332) or Knee Society score (KSS) (P = 0.117) between the one-stage and two-stage revision groups at the 2-year postoperative follow-up. The Kaplan‒Meier survival curves for prosthesis infection-free survival nearly overlapped, with no statistically significant differences between the two groups (P = 0.675). Conclusion: When pathogen identification is achieved through precision diagnostic strategies, the efficacy of one-stage revision surgery combined with targeted antibiotic therapy is comparable to that of two-stage revision surgery.

Objective: This study aimed to identify the risk factors and microbial profiles of patients with culture-negative periprosthetic joint infection (PJI) using metagenomic next generation sequencing (mNGS) and to compare the clinical characteristics and treatment outcomes of culture-negative PJI (CN PJI) with culture-positive PJI (CP PJI).Methods: A retrospective analysis was conducted on 223 patients who met the International Consensus Meeting criteria for PJI and underwent surgical treatment at our hospital between February 2013 and January 2023. Clinical and follow-up data, including microbiological culture results and mNGS findings, were collected. Based on culture results, patients were divided into the CP PJI and CN PJI groups. Risk factors and microbial profiles of CN PJI patients were summarized with the aid of mNGS results. Differences in clinical characteristics and treatment outcomes between the two groups were also analyzed.Results: Among the 223 patients, 168 were in the CP PJI group, and 55 were in the CN PJI group. Risk factors for negative cultures included polymicrobial infections, infections caused by rare pathogens, and prolonged antibiotic use prior to sampling. In the CN PJI group, over a quarter of cases involved polymicrobial infections (25.5%) or rare pathogen infections (38.2%), with Mycoplasma sp. being the most frequently identified rare pathogen (7.2%). Compared to the CP PJI group, the CN PJI group exhibited distinctly longer hospital stays (PP=0.02), and a higher rate of antibiotic-related complications (P=0.026). However, no significant difference was noted in reinfection rates between the two groups (P=0.412).Conclusion: CN PJI presents a unique microbial spectrum and distinct clinical therapeutic characteristics. mNGS offers a more comprehensive understanding of infecting microorganisms, particularly those often missed by conventional culture techniques. With advancements in sample collection, optimized culture methods, molecular diagnostic tools, and early targeted therapies, CN PJI may achieve clinical outcomes comparable to CP PJI.

Objective: The prevailing treatment for chronic periprosthetic joint infection (PJI) is a two‐stage exchange, yet the optimal duration of antibiotic therapy following this procedure remains a topic of debate. This study aimed to determine whether a short course of postoperative antibiotic therapy can maintain infection control rates following a long interval two‐stage exchange (LITE) for PJI.Methods: We conducted a prospective study enrolling patients with chronic PJI who underwent the LITE procedure at our institution from April 2018 to November 2021. Patients were randomly assigned to receive either a long course (12 weeks) or short course (2 weeks) of postoperative antibiotics. The pathogens, antibiotics, inflammatory markers, antibiotic‐related complications, cases of reinfection, or re‐operation were recorded. Continuous variables were analyzed using the two‐sample t‐test or Mann–Whitney U test, and categorical variables were analyzed using Fisher's exact tests. Kaplan–Meier survival analysis was used to compare infection control rates.Results: A total of 60 patients with chronic PJI who completed the LITE procedure were included in the study (30 patients per group). All patients were followed for a minimum of 24 months (mean 39.2 ± 13.0 months). We observed that the infection control rate in the short‐course group was not inferior to that in the long‐course group (96.7% vs. 96.7%, p = 1.000).Conclusions: For patients with chronic PJI undergoing the LITE procedure, a 2‐week course of postoperative antibiotics suffices to maintain infection control rates.Trial Registration: Chinese Clinical Trial Registry: ChiCTR1900027089

Purpose Our goal was to compare the lateralization of ⁶⁸Ga-pentixafor PET/CT with adrenal vein sampling (AVS) in primary aldosteronism (PA) patients with unilateral lesions. Methods We retrospectively enrolled 61 patients with PA and all patients showed unilateral nodular lesions on CT and underwent ⁶⁸Ga-Pentixafor PET/CT. The general clinical data, imaging and AVS results were collected. The diagnostic efficiency of ⁶⁸Ga-Pentixafor PET/CT imaging in PA patients was calculated by visual and semi-quantitative analysis to compare the consistency with AVS, and the correlation between CXCR4 express and ⁶⁸Ga-Pentixafor uptake was performed. Results The study included 42 unilateral PA (UPA) and 19 bilateral PA (BPA). The area under curve (AUC) of ⁶⁸Ga-Pentixafor PET/CT to diagnosis UPA with 10 min maximum standardized uptake value (SUVmax) > 8.17 was 0.82 ([0.70–0.90], P < 0.001), and the sensitivity and specificity were 0.64 and 0.90, respectively. The maximal AUC of ⁶⁸Ga-pentixafor PET/CT for the diagnosis UPA in patients with nodules with a diameter ≥1 cm was 0.87 ([0.73–0.95],P both 68Ga-pentixafor uptake in adrenal lesions was significantly correlated with CXCR4 expression, and statistical differences in ⁶⁸Ga-pentixafor uptake among IRS subgroups. Conclusions ⁶⁸Ga-Pentixafor PET/CT can be helpful for subtyping diagnosis of PA patients with unilateral adrenal nodular, showing significant potential in non-invasive PA classification.

Aims: This aim of this study was to analyze the detection rate of rare pathogens in bone and joint infections (BJIs) using metagenomic next-generation sequencing (mNGS), and the impact of mNGS on clinical diagnosis and treatment.Methods: A retrospective analysis was conducted on 235 patients with BJIs who were treated at our hospital between January 2015 and December 2021. Patients were divided into the no-mNGS group (microbial culture only) and the mNGS group (mNGS testing and microbial culture) based on whether mNGS testing was used or not.Results: A total of 147 patients were included in the no-mNGS group and 88 in the mNGS group. The mNGS group had a higher detection rate of rare pathogens than the no-mNGS group (21.6% vs 10.2%, p = 0.016). However, the mNGS group had lower rates of antibiotic-related complications, shorter hospital stays, and higher infection control rates compared with the no-mNGS group (p = 0.017, p = 0.003, and p = 0.028, respectively), while there was no significant difference in the duration of antibiotic use (p = 0.957). In culture-negative cases, the mNGS group had lower rates of antibiotic-related complications, shorter hospital stays, and a higher infection control rate than the no-mNGS group (p = 0.036, p = 0.033, p = 0.022, respectively), while there was no significant difference in the duration of antibiotic use (p = 0.748).Conclusion: mNGS improves detection of rare pathogens in BJIs. mNGS testing reduces antibiotic-related complications, shortens hospital stay and antibiotic use duration, and improves treatment success rate, benefits which are particularly evident in culture-negative cases.Cite this article: Bone Joint Res 2024;13(8):401–410.