Performance and Hypothetical Impact on Joint Infection Management of the BioFire Joint Infection Panel: a Retrospective Analysis

Prospective evaluation of real-world performance and clinical impact of the Biofire FilmArray joint infection panel

Limitations of culture-based diagnostic approaches in pathogen detection in joint infections (JI) can be overcome by amplification-based, molecular assays. Recently, a syndromic panel PCR (spPCR) assay (Biofire JI panel; BJA) was approved for pathogen identification from synovial fluid (SF). Here, the performance and the clinical impact of the BJA were assessed in comparison to standard of care diagnostics in a prospective cohort of patients presenting with symptoms consistent with JI. One hundred sixty-five synovial fluids underwent analysis using the BJA. The results were compared with culture-based diagnostics. Discrepant results were re-analyzed using species-specific PCRs or 16S-rDNA sequencing. Clinical data from patients were collected to evaluate the impact on patient management. Twenty-seven of 165 (16.3%) synovial fluid cultures grew bacterial pathogens. In 24/27 cases, the BJA results were concordant. In one case, the cultured pathogen was missed, but three additional pathogens were identified. In 11 culture-negative cases, BJA identified a pathogen. Mean turnaround time in culture-positive samples was 14:11 h and 35:17 h in BJA and culture, respectively. In 11 cases, antibiotic therapy was optimized, based on BJA results. This study demonstrates high sensitivity and specificity (96.3% and 97.8%, respectively) of BJA, as well as a shorter turnaround time than culture-based techniques (21 h faster). Based on analysis of clinical data, antibiotic therapy was optimized due to BJA results in 11 cases. Care must be taken, as important pathogens in prosthetic JI are not included in the panel, restricting its value here.IMPORTANCEPathogen detection is critical for targeted management of joint infections; however, cultural detection of pathogens can be challenging. The Biofire Joint Infection Assay (BJA) is a syndromic panel PCR test that allows culture-independent detection of 31 pathogens. The diagnostic performance and clinical impact were evaluated in a cohort of 160 patients with native and prosthetic joint infections. BJA detected concordant pathogens in 24 of 27 culture-positive cases and enabled the detection of additional pathogens in 11 patients. The time to result was significantly shorter than with standard culture-based diagnostics (14 vs 35 h), and BJA allowed optimization of therapy in 11 patients. The data show that BJA is a relevant addition to the diagnostic options for joint infections. Limitations result from incomplete detection of relevant pathogens, especially in prosthetic joint infections. The use of BJA in daily practice must therefore be accompanied by diagnostic stewardship measures.

Molecular diagnostics for perioperative microbial identification in periprosthetic joint infection: A scoping review and proposal of a diagnostic flow chart

Purpose

Periprosthetic joint infections (PJI) are among the most feared complications of joint reconstruction. Unfortunately, traditional cultures often fail to identify the aetiological agents of PJI. Molecular diagnostics can overcome the limitations of standard synovial fluid culture by utilising information from DNA/RNA samples to identify microbial species. The authors conducted a scoping review to evaluate the current state regarding the use of molecular diagnostics in the decision-making process for the surgical treatment of PJI and to create a flowchart based on molecular diagnostics.

Methods

A scoping review was conducted to provide an overview of the literature on molecular diagnostic techniques for detecting perioperative microbial infections in PJI. The population considered included patients undergoing total hip or knee arthroplasty or replacement, with a focus on molecular diagnostic methods within the perioperative period. The database search encompassed PubMed, Embase, Scopus and the Cochrane Library.

Results

Seventy-five articles were included after a preliminary review of 1315 records. Each article was assigned to one of four categories to fulfil the purpose of this review: (1) Polymerase chain reaction (PCR) related studies: n = 18; (2) Next-Generation-Sequencing (NGS) related studies: n = 40; (3) comparative studies, including systematic reviews and meta-analyses, between different molecular diagnostic methodologies: n = 7; and (4) general reviews on nucleic acid-based strategies to detect PJIs: n = 10.

Conclusions

This review confirmed that molecular diagnostics are becoming extremely valuable tools in the decision-making process for PJI treatment. Culture-based techniques still represent the gold standard in PJI microorganism identification, but our review showed that standard culture, in 2025, could be integrated with newer nucleic acid-based strategies.

Level of Evidence

Level I.

An Evaluation of a Syndromic Molecular Panel in Optimising the Microbiological Diagnosis and Antimicrobial Therapy of Suspected Osteoarticular Infections in Paediatric Patients

Background/Objectives: Paediatric osteoarticular infections (POAIs) present unique diagnostic and therapeutic challenges. Microbiological culture (MC) is typically time-consuming and lacks sensitivity, especially when patients have received antibiotics. The BIOFIRE® Joint Infection Panel (BJIP) is a syndromic molecular assay for the direct identification of most pathogens causing POAIs. Methods: We evaluated BJIP in 17 synovial fluids, and then, we retrospectively assessed its utility in 93 off-label specimens (i.e., 25 purulent fluids/biopsies and 68 whole blood samples). All specimens were collected from October 2022 to March 2024 from paediatric patients admitted at the Bambino Gesù Children's Hospital in Rome. Results: A bacterial pathogen was isolated in only one of 17 synovial fluid cultures, while BJIP identified eight additional microorganisms in MC-negative cases. The most frequently detected pathogen was S. aureus (44.5%, 4/9). BJIP performance in synovial fluids showed an overall positive percentage agreement (PPA) and negative percentage agreement (NPA) of 100% and 88.1%, respectively, compared to MC. All positive results (n/N = 9/17) were considered medically significant, with an increase in NPA to 100%. In purulent fluids/biopsies, BJIP and MC were concordant in 72% of cases (n/N = 18/25), with a per-sample PPA and NPA of 90% and 60%, respectively. For whole blood samples, almost all samples were negative by both methods (i.e., reference blood culture and BJIP), and the molecular test did not enable any further microbiological diagnosis. Conclusions: The BIOFIRE® Joint Infection Panel rapidly and accurately enabled or excluded a diagnosis of a POAI (~1 vs. 24-96 h for MC), optimising antimicrobial therapy.

Clinical evaluation of a multiplex PCR-based test for joint infection: a prospective diagnostic accuracy study of forty-nine patients

PURPOSE

The purpose of this study was to evaluate the diagnostic accuracy (sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)) of the PCR-based BioFire® Joint Infection Panel (BJI Panel) against microbiological culture growth for patients suspected of having a native or prosthetic joint infection.

METHODS

Synovial fluid and tissue biopsies were prospectively collected from patients from June 2022 to June 2023. The results of the BJI Panel were compared with those of culture growth.

RESULTS

51 samples were included. Including all pathogens, the sensitivity was 69%, the specificity 89%, the PPV 73% and the NPV 86%. Including only pathogens in the BJI Panel, the sensitivity was 100%, the specificity 90%, the PPV 73% and the NPV 100%.

CONCLUSION

The BJI Panel has a high accuracy for detecting the pathogens in its panel, but the absence of important common pathogens from the panel reduces its sensitivity and NPV. With a short turnaround time and precise pathogen detection, the BJI Panel has the potential to add value as a complementary diagnostic method.

Clinical performance evaluation of the BioFire Joint Infection Panel

The BioFire Joint Infection (JI) Panel offers a significant advancement in the rapid diagnosis of joint infections by facilitating the simultaneous detection of multiple bacterial and fungal pathogens, as well as resistance markers, directly from synovial fluid samples. An article published in the Journal of Clinical Microbiology by Moran et al. (J Clin Microbiol 62:e00182-24, 2024, https://doi.org/10.1128/jcm.00182-24) presents both prospective and retrospective analyses of the panel's real-world clinical application. The study highlights the panel's benefits, such as its rapid turnaround time and ability to identify challenging pathogens, while also discussing its limitations, particularly in detecting certain off-panel organisms.

Effect of Preoperative Antibiotic Therapy on Operative Culture Yield for Diagnosis of Native Joint Septic Arthritis

BACKGROUND

Native joint septic arthritis (NJSA) is definitively diagnosed by a positive Gram stain or culture, along with supportive clinical findings. Preoperative antibiotics are known to alter synovial fluid cell count, Gram stain, and culture results and are typically postponed until after arthrocentesis to optimize diagnostic accuracy. However, data on the impact of preoperative antibiotics on operative culture yield for NJSA diagnosis are limited.

METHODS

We retrospectively reviewed adult cases of NJSA who underwent surgery at Mayo Clinic facilities from 2012 to 2021 to analyze the effect of preoperative antibiotics on operative culture yield through a paired analysis of preoperative culture (POC) and operative culture (OC) results using logistic regression and generalized estimating equations.

RESULTS

Two hundred ninety-nine patients with NJSA affecting 321 joints were included. Among those receiving preoperative antibiotics, yield significantly decreased from 68.0% at POC to 57.1% at OC (P < .001). In contrast, for patients without preoperative antibiotics there was a non-significant increase in yield from 60.9% at POC to 67.4% at OC (P = .244). In a logistic regression model for paired data, preoperative antibiotic exposure was more likely to decrease OC yield compared to non-exposure (odds ratio [OR] = 2.12; 95% confidence interval [CI] = 1.24-3.64; P = .006). Within the preoperative antibiotic group, additional antibiotic doses and earlier antibiotic initiation were associated with lower OC yield.

CONCLUSIONS

In patients with NJSA, preoperative antibiotic exposure resulted in a significant decrease in microbiologic yield of operative cultures as compared to patients in whom antibiotic therapy was held prior to obtaining operative cultures.

Clinical Utility of a Multiplex PCR Panel (BioFire Joint Infection®) in the Adjustment of Empiric Antimicrobial Therapy: Experience in Pediatric Osteoarticular Infections

BACKGROUND/OBJECTIVES

This study aims to evaluate the impact of the PCR multiplex panel (BioFire JI®) on the diagnosis and management of pediatric osteoarticular infections.

METHODS

This retrospective study analyzed data from pediatric patients diagnosed with osteoarticular infections between January 2023 and April 2024. The effectiveness of the PCR multiplex panel in identifying pathogens was compared with traditional culture methods.

RESULTS

In total, 50 patients were identified (66.6% male, 74% under 3 years of age). They were diagnosed as follows: septic arthritis in 46%, osteomyelitis in 26%, and septic osteoarthritis in 22%. An identifiable agent was isolated by conventional culture in 22 cases (44%). Kingella kingae was the predominant pathogen identified, accounting for 50% of cases (11/22), followed by Staphylococcus aureus (9/22). The BioFire JI® Panel PCR demonstrated a sensitivity of 93%, with a specificity of 63% when evaluated against synovial fluid culture as the reference standard. The panel identified seven additional pathogens not detected by conventional culture methods: 2/9 MSSA (22%), 1/1 S. pyogenes (100%), and 4/11 K. kingae (37%), increasing the yield by 14%. The rapid identification of pathogens facilitated timely and targeted therapeutic interventions.

CONCLUSIONS

The PCR multiplex panel (BioFire JI®) improved the diagnosis of pediatric osteoarticular infections.

Evaluation of a BioFire multiplex PCR panel for detection of joint infections using retrospective and prospectively collected specimens

The BioFire Joint Infection Panel (JI panel) is a newly FDA-approved multiplex PCR assay for detection of common bone and joint pathogens with 39 targets which include select Gram-positive and Gram-negative bacteria, yeast, and antimicrobial resistance genes. We evaluated the performance of the JI panel in detecting joint infections in our patient population. Sixty-three frozen, residual joint fluid specimens were retrospectively tested using the JI panel. An additional 104 residual joint fluid specimens were de-identified and prospectively tested within 1 week of collection. Results from routine bacterial cultures were used as the reference standard, which included inoculation to agar plates and blood culture bottles. For the frozen specimens, the JI panel showed a positive percent agreement (PPA) of 92.8% and a negative percent agreement (NPA) of 97.1%. PPA was 71.4% and NPA was 94.8% for fresh specimens. A total of 12 discrepancies were observed among the 167 specimens tested. The JI panel demonstrated good overall agreement with routine culture for the detection of joint infections and may improve timely diagnosis when used in conjunction with bacterial culture. However, potential false-positive and false-negative results were observed in both retrospective and prospective testing of specimens.IMPORTANCEThe BioFire JI panel is a new commercially available multiplex PCR assay for detecting common pathogens causing bone and joint infections. The test is performed directly on joint fluids with a fast turnaround time of 1 hour. Our study shows that while the JI panel overall shows good agreement with routine culture, discrepancies were observed in 7% of cases and results should be interpreted with appropriate clinical context.

The role of BioFire Joint Infection Panel in diagnosing periprosthetic hip and knee joint infections in patients with unclear conventional microbiological results

Aims

This study aimed to evaluate the BioFire Joint Infection (JI) Panel in cases of hip and knee periprosthetic joint infection (PJI) where conventional microbiology is unclear, and to assess its role as a complementary intraoperative diagnostic tool.

Methods

Five groups representing common microbiological scenarios in hip and knee revision arthroplasty were selected from our arthroplasty registry, prospectively maintained PJI databases, and biobank: 1) unexpected-negative cultures (UNCs), 2) unexpected-positive cultures (UPCs), 3) single-positive intraoperative cultures (SPCs), and 4) clearly septic and 5) aseptic cases. In total, 268 archived synovial fluid samples from 195 patients who underwent acute/chronic revision total hip or knee arthroplasty were included. Cases were classified according to the International Consensus Meeting 2018 criteria. JI panel evaluation of synovial fluid was performed, and the results were compared with cultures.

Results

The JI panel detected microorganisms in 7/48 (14.5%) and 15/67 (22.4%) cases related to UNCs and SPCs, respectively, but not in cases of UPCs. The correlation between JI panel detection and infection classification criteria for early/late acute and chronic PJI was 46.6%, 73%, and 40%, respectively. Overall, the JI panel identified 12.6% additional microorganisms and three new species. The JI panel pathogen identification showed a sensitivity and specificity of 41.4% (95% confidence interval (CI) 33.7 to 49.5) and 91.1% (95% CI 84.7 to 94.9), respectively. In total, 19/195 (9.7%) could have been managed differently and more accurately upon JI panel evaluation.

Conclusion

Despite its microbial limitation, JI panel demonstrated clinical usefulness by complementing the traditional methods based on multiple cultures, particularly in PJI with unclear microbiological results.

Multiplex PCR in septic arthritis and periprosthetic joint infections microorganism identification: Results from the application of a new molecular testing diagnostic algorithm

Purpose

Pathogen identification is key in the treatment of septic arthritis (SA) and periprosthetic joint infections (PJI). This study evaluates the outcome of the application of a new, score-based SA and PJI diagnostic algorithm, which includes the execution of molecular testing on synovial fluid.

Methods

A score-based diagnostic algorithm, which includes serologic and synovial fluid markers determination using multiplex PCR (mPCR) and Next Generation Sequencing (NGS) molecular testing, has been applied to a consecutive series of patients with clinically suspected SA or PJI. Patients with a score ≥6 underwent synovial fluid molecular testing, together with traditional culture, to identify the pathogen and its genetically determined antibiotic resistance.

Results

One hundred and seventeen joints in 117 patients (62.5% women; average age 73 years) met the criteria for possible SA/PJI. The affected joint was the knee in 87.5% (joint replacement 66.5%; native joint 21%) and the hip in 12.5% (all replaced joints). 43/117 patients (36.7%) were ultimately diagnosed with SA/PJI. Among the various testing technologies applied, mPCR was the main determinant for pathogen identification in 63%, standard culture in 26%, and mNGS in 11%. Staphylococcus aureus and Enterococcus faecalis were the top two microorganisms identified by mPCR, while Staphylococcus epidermidis was the prevalent organism identified by NGS. mPCR detected the presence/absence of the genetically determined antibiotic resistance of all identified microorganisms. The average timeframe for pathogen identification was 3.13 h for mPCR, 4.5 days for culture, and 3.2 days for NGS.

Conclusions

Molecular diagnostic technologies represent an innovative screening for fast microorganism identification when a joint infection is clinically suspected.

Level of Evidence

Level IV, case series.

An overview of point-of-care testing for infections in critically ill patients

INTRODUCTION

Molecular diagnostic systems for point-of-care (POC) testing are nowadays routinely used and are part of many labs. Although often intended for bedside use outside of the microbiology lab, there is still room for expansion.

AREAS COVERED

This review discusses the two techniques that are currently the most widespread, real-time polymerase-chain reaction (RT-PCR) and loop-mediated isothermal amplification (LAMP). An overview is provided of the various manufacturers and products as well as the evidence and current use in clinical practice. The article further sheds light on some newer techniques, such as CRISPR-based diagnostics and lab-on-a-chip, which are still in development.

EXPERT OPINION

With many new platforms and techniques still in the pipeline and their potential currently not yet fully exploited, we expect the use of molecular POC testing to increase in the years to come. However, even when used in hospital - in lab, the main advantages of the tests being fast and easy to perform already provide significant benefits in terms of patient outcome.

Potential value of a rapid syndromic multiplex PCR for the diagnosis of native and prosthetic joint infections: a real-world evidence study

Introduction: The BIOFIRE Joint Infection (JI) Panel is a diagnostic tool that uses multiplex-PCR testing to detect microorganisms in synovial fluid specimens from patients suspected of having septic arthritis (SA) on native joints or prosthetic joint infections (PJIs). Methods: A study was conducted across 34 clinical sites in 19 European and Middle Eastern countries from March 2021 to June 2022 to assess the effectiveness of the BIOFIRE JI Panel. Results: A total of 1527 samples were collected from patients suspected of SA or PJI, with an overall agreement of 88.4 % and 85 % respectively between the JI Panel and synovial fluid cultures (SFCs). The JI Panel detected more positive samples and microorganisms than SFC, with a notable difference on Staphylococcus aureus, Streptococcus species, Enterococcus faecalis, Kingella kingae, Neisseria gonorrhoeae, and anaerobic bacteria. The study found that the BIOFIRE JI Panel has a high utility in the real-world clinical setting for suspected SA and PJI, providing diagnostic results in approximately 1 h. The user experience was positive, implying a potential benefit of rapidity of results' turnover in optimising patient management strategies. Conclusion: The study suggests that the BIOFIRE JI Panel could potentially optimise patient management and antimicrobial therapy, thus highlighting its importance in the clinical setting.