Serum D-dimer as a diagnostic index of PJI and retrospective analysis of etiology in patients with PJI

Role of Serum Biomarkers in Differentiating Periprosthetic Joint Infections from Aseptic Failures after Total Hip Arthroplasties

Background/Objectives: Periprosthetic joint infection (PJI) is a disastrous complication after joint replacement procedures as the diagnosis remains a significant challenge. The objective of this study is to assess the accuracy and test the interdependency of the proposed compound serum biomarkers for the diagnosis of PJI after total hip arthroplasties (THA). Methods: From January 2019 to December 2023, 77 consecutive cases that underwent revision total hip arthroplasties (rTHA) were included in a single-retrospective, observational cohort study. A total of 32 arthroplasties were classified as having septic complications using the European Bone and Joint Infection Society (EBJIS) definition from 2021, while the other 45 cases were assigned as aseptic failures (AF). Results: In the univariate analysis between the two groups created, statistically significant differences (p < 0.005) were found for the following variables: time from primary arthroplasty to symptom onset (Time PA-SO), neutrophil count, Lymphocyte count, haematocrit level (HCT) and haemoglobin level (HGB), C-reactive protein (CRP), the neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), monocyte lymphocyte ratio (MLR), systemic inflammation index (SII), systemic inflammation response index (SIRI), and aggregate inflammation systemic index (AISI). The ROC curve analysis showed that the SII (sensitivity 90.6% and specificity 62.2%) and the NLR (sensitivity 84.4% and specificity 64.4%) are the most accurate biomarkers. The multivariate analysis confirmed that NLR > 2.63 (p = 0.006), PLR > 147 (p = 0.021), MLR > 0.31 (p = 0.028), SII > 605.31 (p = 0.002), SIRI > 83.34 (p = 0.024), and AISI > 834.86 (p = 0.011) are all closely related to PJI diagnosis independently. Conclusions: The proposed serum biomarkers can be correlated with PJI diagnosis with the reserve of relatively low specificities.

Efficacy analysis of clinical serological indicators in the diagnosis of postoperative periprosthetic joint infection in patients with rheumatoid arthritis or osteoarthritis

PURPOSE

To investigate the incidence of periprosthetic joint infection (PJI) in patients with rheumatoid arthritis (RA) or osteoarthritis (OA) after primary joint arthroplasty; to analyze the optimal cut-off values of clinical serum markers C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and D-dimer for the diagnosis of PJI in RA patients; and to explore their diagnostic efficacy and clinical significance.

METHODS

Clinical data of 15,702 patients with RA (578) or OA (15,124) who underwent total joint arthroplasty from 2013 to 2021 were retrospectively analyzed. Serum CRP, ESR, and D-dimer were recorded for each patient, and subject characteristic curves were used to determine the optimal threshold values of CRP, ESR, and D-dimer for RA-PJI and OA-PJI and to compare the areas under the curves to assess the diagnostic efficacy of the optimal threshold values of serologic indices for RA-PJI.

RESULTS

The five year incidence of PJI was 6.92% in RA patients and 0.67% in OA patients. The optimal thresholds of CRP, ESR, and D-dimer for the diagnosis of RA-PJI were respectively 13.85 mg/L, 33.02 mm/h, and 796.50 ng/mL. The sensitivities of the optimal thresholds were respectively 67.6%, 62.2%, and 56.8%, and the specificities were 74.7%, 60.4%, and 74.4%.

CONCLUSION

RA patients have a higher incidence of PJI than OA patients. The optimal thresholds for CRP, ESR, and d-dimer for the diagnosis of PJI were higher in RA patients than in OA patients, but the sensitivity and specificity of the diagnosis were not as good as in OA patients.

Current Status and Perspectives of Diagnosis and Treatment of Periprosthetic Joint Infection

Periprosthetic joint infection (PJI) is a catastrophic complication following joint replacement surgery, posing significant challenges to orthopedic surgeons. Due to the lack of a definitive diagnostic gold standard, timely treatment initiation is problematic, resulting in substantial economic burdens on patients and society. In this review, we thoroughly analyze the complexities of PJI and emphasize the importance of accurate diagnosis and effective treatment. The article specifically focuses on the advancements in diagnostic techniques, ranging from traditional pathogen culture to advanced molecular diagnostics, and discusses their role in enhancing diagnostic accuracy. Additionally, we review the latest surgical management strategies, including everything from debridement to revision surgeries. Our summary aims to provide practical information for the diagnosis and treatment of PJI and encourages further research to improve diagnostic accuracy and treatment outcomes.

Diagnostic value of albumin/fibrinogen ratio and C-reactive protein/albumin/globulin ratio for periprosthetic joint infection: a retrospective study

Background

The study aims to explore diagnostic value of albumin/fibrinogen ratio (AFR) and C-reactive protein (CRP)/albumin (ALB)/globulin (GLO) ratio (CAGR) for periprosthetic joint infection (PJI).

Methods

A retrospective analysis was conducted on clinical data collected from 190 patients who had joint replacement surgery in Qilu Hospital of Shandong University (Qingdao), from January 2017 to December 2022. Based on the occurrence of PJI after surgery, patients were divided as an infection group (10 cases) and non-infection group (180 cases). Diagnostic indicators were analyzed, univariate and multivariate logistic regression analyses were further performed to identify factors related to PJI. Sensitivity and specificity of AFR and CAGR, both individually and in combination, were calculated using ROC curves, and their diagnostic performance was compared based on the area under the curve (AUC).

Results

Levels of CRP, ESR, FIB, GLO, and CAGR were significantly higher in the infection group than in non-infection group (P < 0.05). Levels of ALB and AFR were significantly lower in infection group (P < 0.05). Multivariate logistic regression analysis reviewed that CRP (OR = 3.324), ESR (OR = 2.118), FIB (OR = 3.142), ALB (OR = 0.449), GLO (OR = 1.985), AFR (OR = 0.587), and CAGR (OR = 2.469) were factors influencing PJI (P < 0.05). The AUC for AFR and CAGR in diagnosing PJI were 0.739 and 0.780, while AUC for their combined detection was 0.858.

Conclusion

Abnormal levels of AFR and CAGR are associated with PJI, and their combined use has certain diagnostic value for PJI.

Higher D-dimer and activated partial thromboplastin time are poor prognostic factors in patients with peritoneal dialysis-related peritonitis

INTRODUCTION

Coagulation system dysfunction is associated with adverse outcomes of peritoneal dialysis (PD) and bacterial infection. We investigated the association between coagulation system and treatment failure of peritoneal dialysis-related peritonitis (PDRP).

METHODS

We collected records of patients aged ≥18 years with PDRP. PDRP episodes were divided into: shortened activated partial thromboplastin time (APTT) group and prolonged APTT group, low D-dimer (DD) group and high DD group. The baseline characteristics of the groups were collected and compared. The association between APTT, DD and treatment failure of PDRP was analyzed using logistic regression analysis.

RESULTS

Thirty episodes of treatment failure were observed in 110 episodes of PDRP in our study. After adjusting for variables, prolonged APTT (OR = 1.166 [1.049-1.296], p = 0.004) or high level of DD (OR = 1.374 [1.057-1.787], p = 0.017) was associated with treatment failure of PDRP.

CONCLUSION

Prolonged baseline APTT or high level of DD increased the risk of treatment failure of PDRP.

Fibrinogen, albumin-to-globulin ratio, and fibrinogen to albumin-to-globulin ratio may be potential diagnostic biomarkers for infected tibial nonunion

AIM

The accurate preoperative diagnosis of infected tibial nonunion remains challenging. Hence, we evaluated the diagnostic potential of novel biomarkers for infected tibial nonunion.

METHODS

This single-center retrospective study was conducted in 252 patients divided into two groups: infected tibial nonunion (67 patients) and aseptic tibial nonunion (185 patients). The preoperative clinical biomarkers included D-dimer, fibrinogen, albumin, globulin, total protein, and C-reactive protein (CRP) levels; albumin-to-globulin ratio (AGR); erythrocyte sedimentation rate (ESR); and white blood cell (WBC) count. Receiver operating characteristic (ROC) curves, sensitivity, and specificity were utilized to compare the biomarkers' diagnostic potential.

RESULTS

The area under the curve (AUC) values for fibrinogen and AGR were 0.829 and 0.821, respectively, suggesting similarly good diagnostic potentials for infected tibial nonunion. Fibrinogen and AGR were better diagnostic biomarkers for infected tibial nonunion than the WBC count; ESR; D-dimer, albumin, globulin, CRP, and total protein levels, whose AUC values were 0.623, 0.684, 0.741, 0.797, 0.765, 0.715, and 0.554, respectively. The sensitivity and specificity of fibrinogen with a cut-off value of 3.35 g/L were 71.64% and 84.86%, respectively. The corresponding values for AGR with a cut-off value of 1.33 were 73.13% and 86.49%. Moreover, the fibrinogen-AGR (FAGR), i.e., the combination of fibrinogen and AGR, had the highest diagnostic accuracy for infected tibial nonunion (AUC = 0.906). The optimal FAGR cut-off was 2.69, with fair sensitivity (74.63%) but the highest specificity (94.59%).

CONCLUSION

Fibrinogen, AGR, and FAGR are promising biomarkers for the diagnosis of infected tibial nonunion.

Diagnosis of Periprosthetic Joint Infection: The Utility of Biomarkers in 2023

Periprosthetic joint infection (PJI) is a rare yet devastating complication following total joint arthroplasty (TJA). Early and accurate diagnosis of PJI is paramount in order to maximize the chances of successful treatment. However, we are yet to identify a single "gold standard" test for the diagnosis of PJI. As a result, the diagnosis of PJI is often challenging. Currently, the 2018 ICM definition of PJI is the only validated diagnostic criteria available. This article will review the importance of serum and synovial biomarkers in the diagnosis of PJI. In addition, it will provide a brief overview of the emerging modalities for the identification of infections in this setting.

Which Combination is Best? A Comparison of the Predictive Potential of Serum Biomarker Combinations to Diagnose Periprosthetic Joint Infection

BACKGROUND

Without a gold standard test, recent periprosthetic joint infections (PJI) literature has explored the utility of combining serological results, with promising findings. However, previous studies evaluated fewer than 200 patients and often studied only 1 to 2 test combinations. The purpose of this study was to accumulate a large single institution cohort of revision total joint arthroplasty (rTJA) patients to determine the diagnostic utility of combination serum biomarkers to identify PJI.

METHODS

A single institution longitudinal database was assessed to identify all patients who underwent rTJA from 2017 to 2020. There were 1,363 rTJA patients (715 rTKA patients and 648 rTHA patients) including 273 PJI cases (20%) analyzed. The PJI was diagnosed post-rTJA utilizing 2011 Musculoskeletal Infection Society (MSIS) criteria. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), D-dimer, and interleukin 6 (IL-6) were systematically collected for all patients.

RESULTS

The rTKA combination markers of CRP+ESR (sensitivity: 78.3%, specificity: 88.8%, positive predictive value (PPV): 70.0%, negative predictive value (NPV): 92.5%), CRP+D-dimer (sensitivity: 60.5%, specificity: 92.6%, PPV: 63.4%, NPV: 91.7%), and CRP+IL-6 (sensitivity: 38.5%, specificity: 100.0%, PPV: 100.0%, NPV: 92.9%) all yielded higher specificity than CRP alone (sensitivity: 94.4%, specificity: 75.0%, PPV: 55.5%, NPV: 97.6%). Similarly, the rTHA combination markers of CRP+ESR (sensitivity: 70.1%, specificity: 88.8%, PPV: 58.1%, NPV: 93.1%), CRP+D-dimer (sensitivity: 57.1%, specificity: 90.1%, PPV: 43.2%, NPV: 94.1%), and CRP+IL-6 (sensitivity: 21.4%, specificity: 98.4%, PPV: 60.0%, NPV: 91.7%) all yielded higher specificity than CRP alone (sensitivity: 84.7%, specificity: 77.5%, PPV: 45.4%, NPV: 95.8%).

CONCLUSIONS

Overall, in diagnosing PJI for both rTKA and rTHA, two marker combinations yielded higher specificity, while three marker combinations yielded higher sensitivity compared to CRP alone. However, compared to all two and three marker combinations, CRP demonstrated superior overall diagnostic utility. These findings suggest that routine combination testing of markers for PJI diagnosis may be excessive and an unnecessary use of resources, especially in resource-limited situations.

Utility of D-dimer in total joint arthroplasty

As the number of patients receiving total joint replacements continues to rise, considerable attention has been directed towards the early detection and prevention of postoperative complications. While D-dimer has long been studied as a diagnostic tool in venous thromboembolism (VTE), this assay has recently received considerable attention in the diagnosis of periprosthetic joint infection (PJI). D-dimer values are substantially elevated in the acute postoperative period after total joint arthroplasty, with levels often exceeding the standard institutional cutoff for VTE (500 µg/L). The utility of D-dimer in detecting VTE after total joint replacement is currently limited, and more research to assess its value in the setting of contemporary prophylaxis protocols is warranted. Recent literature supports D-dimer as a good to excellent biomarker for the diagnosis of chronic PJI, especially when using serum sample technique. Providers should exercise caution when interpreting D-dimer levels in patients with inflammatory and hypercoagulability disorders, as the diagnostic value is decreased. The updated 2018 Musculoskeletal Infection Society criteria, which includes D-dimer levels > 860 µg/L as a minor criterion, may be the most accurate for diagnosing chronic PJI to date. Larger prospective trials with transparent lab testing protocols are needed to establish best assay practices and optimal cutoff values for D-dimer in the diagnosis of PJI. This review summarizes the most current literature on the value of D-dimer in total joint arthroplasty and elucidates areas for future progress.

Combination of albumin-to-globulin ratio and plasma fibrinogen is a sensitive tool for preoperative screening of infected nonunion in patients undergoing reoperation after open reduction and internal fixation: a retrospective study

Background

Accurate preoperative diagnosis of infected nonunion remains a challenge. Here, we evaluated the diagnostic potential of novel biomarkers for infected nonunion.

Methods

A cohort of 275 patients who underwent surgery for suspected septic nonunion after open reduction and internal fixation were enrolled. Preoperatively analyzed clinical parameters included white blood cell (WBC) count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), albumin, globulin, albumin-to-globulin ratio (AGR), plasma D-dimer, plasma fibrinogen, platelet count (PC), monocyte-lymphocyte ratio (MLR), neutrophil–lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR). Receiver operating characteristic (ROC) curves, sensitivity, and specificity were utilized to compare the diagnostic potential of those biomarkers.

Results

The WBC count and levels of CRP, ESR, NLR, MLR, PLR, PC, plasma D-dimer, plasma fibrinogen, and globulin in infected nonunion patients were significantly higher (p < 0.05) than those in aseptic patients. The albumin and AGR levels of the infected nonunion group were significantly lower (p < 0.05) than the aseptic group. The ROC curve analysis showed that the diagnostic accuracy of AGR and plasma fibrinogen was good. The combination of AGR with plasma fibrinogen had the highest area under the curve (AUC) (0.916). The sensitivity and specificity were 70.27% and 91.04% for AGR, and 67.57% and 84.08% for plasma fibrinogen, respectively. The combination of AGR with plasma fibrinogen showed a sensitivity of 86.49% and specificity of 92.54%. In patients with comorbidities, the diagnostic accuracy of the combination of AGR with plasma fibrinogen was also good.

Conclusions

AGR and plasma fibrinogen are promising biomarkers to improve the diagnosis of infected nonunion. The combination of AGR with plasma fibrinogen is a sensitive tool for screening infected nonunion.

Usefulness of serum D-dimer and platelet count to mean platelet volume ratio to rule out chronic periprosthetic joint infection

Background: Diagnosing periprosthetic joint infection (PJI) is challenging and usually requires the evaluation of several biomarkers. Our main aim was to evaluate the usefulness of D-dimer levels as well as the platelet count (PC) to mean platelet volume (MPV) ratio serum as biomarkers to rule out chronic knee and hip infection. Methods: The study enrolled a prospective cohort of 93 patients undergoing hip or knee revision. D-dimer values, PC to MPV ratio, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were preoperatively determined and evaluated as a predictor of PJI. The definitive diagnosis of PJI was established according to the 2018 International Consensus Meeting criteria. Results: A total of 24 (25.8 %) cases were postoperatively diagnosed with PJI. The median D-dimer value was significantly higher ( p   <  0.001) for patients with PJI (1950 ng mL- 1 ) than for patients with aseptic failure (700 ng mL- 1 ). The area under the receiver operating characteristic curves for D-dimer, CRP and ESR was 0.820, 0.793 and 0.791 respectively. D-dimer  ≥  950 ng mL- 1 (91 % sensitivity, 64 % specificity), CRP  ≥  1.95 mg dL- 1 (61 % sensitivity, 90 % specificity) and ESR  >  20 (74 % sensitivity, 82 % specificity) were identified as the values with the best balance between sensitivity and specificity. The mean PC to MPV ratio was 37.0 for PJI patients and 29.8 for patients in the aseptic revision cohort ( p = 0 .067). Conclusions: Serum D-dimer levels appear very unlikely to remain normal in the presence of chronic PJI. The 91 % sensitivity when considering 950 ng mL- 1 as the threshold highlights D-dimer as the most accurate initial test to rule out chronic PJI. Conversely, the PC to MPV ratio may be of limited value for accurately diagnosing PJI.

Diagnostic value of platelet indices in infected nonunion: a retrospective study

BACKGROUND

The diagnostic value of platelet indices has been evaluated in various infectious diseases but not in infected nonunion. The purpose of this study was to assess the usefulness of platelet indices for diagnosis of infected nonunion after open reduction and internal fixation.

METHODS

This retrospective study was performed in patients who underwent primary fracture nonunion revision surgeries from January 2016 to December 2021. A total of 297 patients were included in the study: 96 with infected nonunion (group A) and 201 with aseptic nonunion (group B). Receiver operator characteristic (ROC) curve analysis was performed to evaluate diagnostic value of each index. Area under the curve (AUC), sensitivity, specificity, and positive and negative predictive values were calculated and compared.

RESULTS

Demographic characteristics were comparable between the two groups. White blood cell (WBC) count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), plasma fibrinogen, plasma D-dimer, platelet count (PC), plateletcrit, and ratio of platelet count to mean platelet volume (PC/MPV) were significantly higher, and MPV and platelet distribution width (PDW) significantly lower, in group A than in group B (P < 0.05). ROC analysis showed PC/MPV and plasma fibrinogen to have better diagnostic value than the other coagulation indicators (AUC of 0.801 and 0.807, respectively). The combination of ESR, plasma fibrinogen, and PC/MPV had good sensitivity and specificity for diagnosis of infected nonunion. PC/MPV had better diagnostic value than ESR and plasma fibrinogen in the subgroup of patients with coagulation-related comorbidities.

CONCLUSIONS

Plasma fibrinogen and PC/MPV ratio might be useful parameters for early diagnosis of infected nonunion.

The accuracy of D-dimer in the diagnosis of periprosthetic infections: a systematic review and meta-analysis

Background

Periprosthetic joint infection (PJI) is a devastating complication after total hip arthroplasty (THA) or total knee arthroplasty (TKA). It is scarce and contradicting evidence supporting the use of serum D-dimer to diagnose PJI in revision THA and TKA. This systematic review and meta-analysis aimed to investigate the accuracy of D-dimer in the diagnosis of periprosthetic infections.

Methods

The PubMed, Embase, Web of Science were systematically searched from the inception dates to August 15, 2020. We included all diagnostic studies of D-dimer in the diagnosis of periprosthetic infections. The literature's quality was evaluated by the QUADAS-2 tool, and Stata16 and Revman5.3 software carried out the meta-analysis.

Results

Of 115 citations identified by the search strategy, 10 studies (comprising 1756 participants) met the inclusion criteria. The literature quality assessment results show that most of the literature is low-risk bias literature. The combined sensitivity of D-dimer in diagnosing periprosthetic infections was 0.81 (95% confidence interval [CI] 0.71–0.88), combined specificity was 0.74 (95% CI 0.61–0.84), combined positive likelihood ratio was 3.1 (95% CI 2.0–5.0), combined negative likelihood ratio 0.26 (95% CI 0.16–0.41), combined diagnosis odds ratio 12 (95% CI 5–27), area under the Summary Receiver Operator Characteristic Curve (SROC) is 0.85 (95% CI 0.81–0.88). The data are statistically significant.

Conclusion

D-dimer has a high diagnostic value in diagnosing PJI and has clinical significance in diagnosing periprosthetic infection. In addition, there are relatively few studies on the threshold of D-dimer, different sampling types, different laboratory detection methods, and different races, so more prospective trials with large samples, multi-centers, and scientific design should be carried out in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03001-y.

The poor accuracy of D-dimer for the diagnosis of prosthetic joint infection but its potential usefulness in early postoperative infections following revision arthroplasty for aseptic loosening

BACKGROUND

D-dimer was introduced in 2018 as an alternative biomarker for C-reactive protein (CRP) in the diagnostic of prosthetic joint infection (PJI) criteria of the Musculoskeletal Infection Society. We assessed the accuracy of plasma D-dimer for the diagnosis of early, delayed, and late PJI according to Infectious Diseases Society of America (IDSA) criteria, and whether persistently high levels of D-dimer in cases of aseptic loosening (AL) may be predictive of subsequent implant-related infection.

METHODS

A prospective study of a consecutive series of 187 revision arthroplasties was performed at a single institution. Septic (n = 39) and aseptic revisions (n = 141) were classified based on IDSA criteria. Preoperative assessment of CRP, erythrocyte sedimentation rate (ESR) and D-dimer was performed. Receiver operating curves were used to determine maximum sensitivity and specificity of the biomarkers. The natural progress of D-dimer for AL cases was followed up either until the date of implant-related infection at any time during the first year or 1 year after revision in patients without failure. Clinical outcomes for those AL cases included infection-related failure that required a new surgery or need for antibiotic suppression.

RESULTS

Preoperative D-dimer level was significantly higher in PJI cases than in AL cases (p = 0.000). The optimal threshold of D-dimer for the diagnosis of PJI was 1167 ng/mL. For overall diagnosis of PJI, C-reactive protein (CRP) achieved the highest sensitivity (84.6%), followed by erythrocyte sedimentation rate (ESR) and D-dimer (82% and 71.8%, respectively). Plasma D-dimer sensitivity was lower for all PJI types. When combinations of 2 tests were studied, the combined use of ESR and CRP achieved the best accuracy for all types of PJI (76.9%). 4.25% of AL cases had implant failure due to implant-related infection during the first year after the index revision arthroplasty, only the cases with early failure maintained high D-dimer levels.

CONCLUSIONS

Plasma D-dimer did not offer an improvement over the individual or combined diagnosis for any type of PJI according to IDSA criteria. Persistently raised levels of D-dimer after revision arthroplasty in AL cases might be used to effectively diagnose early postoperative infection.

Thromboelastography parameters in diagnosing periprosthetic joint infection and predicting reimplantation timing

BACKGROUND

Coagulation-related biomarkers are drawing new attention in the diagnosis of periprosthetic joint infection (PJI). The thromboelastography (TEG) assay provides a comprehensive assessment of blood coagulation; therefore, it could be a promising test for PJI. This study aims to assess the value of TEG in diagnosing PJI and to determine the clinical significance of TEG in analysing reimplantation timing for second-stage revision.

METHODS

From October 2017 to September 2020, 62 patients who underwent revision arthroplasty were prospectively included. PJI was defined by the 2011 Musculoskeletal Infection Society criteria, in which 23 patients were diagnosed with PJI (Group A), and the remaining 39 patients were included as having aseptic loosening (Group B). In group A, 17 patients completed a two-stage revision in our centre. C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), D-dimer, and TEG parameters (clotting time, α-angle, MA [maximum amplitude], amplitude at 30 min, and thrombodynamic potential index) were measured preoperatively in all included patients. In addition, receiver operating characteristic curves were used to evaluate the diagnostic value of these biomarkers.

RESULTS

ESR (area under curve [AUC], 0.953; sensitivity, 81.82; specificity, 94.87) performed best for PJI diagnosis, followed by MA (AUC, 0.895; sensitivity, 82.61; specificity, 97.44) and CRP (AUC, 0.893; sensitivity, 82.61; specificity, 94.74). When these biomarkers were combined in pairs, the diagnostic value improved compared with any individual biomarker. The overall success rate of the two-stage revision was 100%. Furthermore, ESR and MA were valuable in determining the time of reimplantation, and their values all decreased below the cut-off values before reimplantation.

CONCLUSION

TEG could be a promising test in assisting PJI diagnosis, and a useful tool in judging the proper timing of reimplantation.

The diagnostic effect of α-defensin, D-dimer, and IL-6 in periprosthetic joint infection: A systematic review and diagnostic meta-analysis

BACKGROUND

Periprosthetic joint infection (PJI) is the most common complication after artificial joint replacement as previously reported. However, the main problem at present is its difficulty in diagnosis. This systematic review and meta-analysis aimed to compare the diagnostic accuracy of α-defensin, D-dimer, and interleukin-6 (IL-6) in clinical practice.

METHOD

Online databases were systematically searched until June 18th, 2020 with keywords and medical sub-headings terms. Studies mentioned the sensitivity and specificity of biological markers in detecting PJI were included in our study. The sensitivity, specificity, and diagnostic odds ratios (DORs) were obtained after integration.

RESULTS

A total of 34 studies with 1036 patients diagnosing as PJI were included for comparing α-defensin, D-dimer, and IL-6. The sensitivity and specificity of α-defensin for PJI were 0.88 and 0.96, and the DOR was 189 (95% CI 72-496), respectively. The sensitivity and specificity of D-dimer (0.82 and 0.72) and IL-6 (0.80 and 0.89) were lower than α-defensin.

CONCLUSION

The detection of α-defensin is a promising biomarker for diagnosing PJI. The optional cut-off needs to be curtained when using other biomarkers.

The role of D-dimer in periprosthetic joint infection: a systematic review and meta-analysis

OBJECTIVES

The current literature on diagnosis of periprosthetic joint infection (PJI) provides controversial evidence on the diagnostic accuracy of D-dimer. Therefore, this critical literature search and meta-analysis was aimed to summarize the diagnostic accuracy of D-dimer for diagnosing PJI.

CONTENT

We searched MEDLINE, Scopus, and Web of Science, for studies on D-dimer for diagnosing PJI, according to the PRISMA flowchart. QUADAS was used for assessing study quality. Sensitivity, specificity, positive (PLR) and negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were analyzed using bivariate diagnostic random-effects model. The area under the receiver-operating curve (AUC-ROC) was calculated. Subgroup analysis and univariate meta-regression were carried out for detecting potential sources of heterogeneity.

SUMMARY

We included 12 articles, totaling 1,818 patients (539 with PJI). The pooled sensitivity and specificity of D-dimer for diagnosing PJI were 0.739 (95% CI: 0.616-0.833) and 0.785 (95% CI: 0.679-0.863). The pooled PLR, NLR, DOR were 3.359 (95% CI, 2.340-4.821), 0.295 (95% CI, 0.180-0.484), and 11.787 (95% CI, 5.785-24.018). The cumulative ROC plot displayed an AUC of 0.688 (95% CI, 0.663-0.713; p<0.001). No threshold effects could be observed. The type of blood sample was identified as possible source of heterogeneity for DOR (p=0.01).

OUTLOOK

Evidence emerged from this meta-analysis suggests that D-dimer displays sufficient diagnostic accuracy to rule out PJI. The type of blood sample (plasma vs. serum) and the study design could influence the results in terms of DOR and sensitivity. However, further perspective studies would be needed to validate its potential diagnostic usefulness.

The hepatoprotective efficacy and biological mechanisms of three phenylethanoid glycosides from cistanches herba and their metabolites based on intestinal bacteria and network pharmacology

Echinacoside (ECH), acteoside (ACT), and isoacteoside (ISAT), the typical phenylethanoid glycosides (PhGs) in cistanches herba, have various pharmacological activities. However, the ECH, ACT and ISAT have extremely low oral bioavailability, which is related to their metabolism under the intestinal flora. Previous studies showed that intestinal metabolites were the hepatoprotective substances in vivo, but the research on whether PhGs has effects without intestinal bacteria has not been studied. In this paper, ECH, ACT and ISAT were incubated with human or rat intestinal bacteria for 36 h. After incubating with human bacteria for 36 h, three prototype compounds were not detected and were mainly biotransformed to 3-HPP and HT. In the network pharmacology, a total of 6 common targets were obtained by analysing the prototypes, the metabolites and the liver injury. It was found that the combinations of three metabolites and common targets were more stable than those of the prototypes and common targets by molecular docking. Meanwhile, hepatocellular apoptosis, proliferation, inflammation and oxidative responses might play important roles in the mechanisms of the metabolites exerting hepatoprotective activities. Then normal and pseudo-sterile mice experiments were adopted to further compare the hepatoprotective activities of prototypes and metabolites. Animal experiment results showed that the prototypes and the metabolites in the normal mice had significantly hepatoprotective activity. Interestingly, in the pseudo-germfree mice, the metabolites showed significant hepatoprotective effect, but the prototypes had not effect. It indicated that the prototype cannot exert liver protective activity without the effect of intestinal bacteria.

A retrospective comparison of thromboelastography and conventional coagulation parameters for periprosthetic joint infection diagnosis and reimplantation timing

PURPOSE

The diagnostic significance of coagulation parameters in periprosthetic joint infection (PJI) is currently attracting increasing attention. We assessed the diagnostic accuracy of thromboelastography (TEG) for PJI and compared the values of various coagulation indicators for PJI diagnosis and reimplantation timing.

METHODS

We enrolled 250 patients undergoing revision for aseptic failure (Group A), revision for PJI (Group B), or reimplantation (Group C) during 2013-2020. C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), representative coagulation-related indicators (reaction time [R], clotting time [K], angle and maximum amplitude [MA]) of TEG and routine coagulation indicators, including fibrinogen, D-dimer, fibrin degradation product (FDP), platelets count (PC), mean platelet volume (MPV), distribution width (PDW) and plateletcrit (PCT) as well as PC/MPV ratio(PVR)were measured preoperatively. Receiver operating characteristic (ROC) curves were used to evaluate the utility of all tested indicators for assessing infection.

RESULTS

All the indicators showed significant differences between groups A and B (P < 0.05) and, except for D-dimer, FDP, MPV and R, between groups B and C (P < 0.05). Similar differences were also observed in biomarkers before first-stage revision and second-stage reimplantation. ROC curves showed that fibrinogen, K, angle and MA outperformed the other coagulation indicators, with areas under the curve of 0.864 to 0.893 and threshold values of 3.55 g/L, 1.2 min, 72.4 deg and 69.1 mm, respectively. The multiple tests of TEG indices (K, angle and MA) and traditional inflammatory markers (CRP and ESR) or conventional coagulation indicators (fibrinogen, PC and PVR) had good sensitivity and specificity for PJI diagnosis, and the diagnostic values of TEG and platelet-associated indicators (PC and PVR) varied in the different subgroups.

CONCLUSION

TEG was closely related to PJI and could serve as a valuable technique for identifying residual infection before reimplantation. Fibrinogen showed high diagnostic accuracy for PJI and effectively guided the timing of reimplantation.

The change in plasma D-dimer does not help to guide the timing of reimplantation in two stage exchange for periprosthetic joint infection

D-dimer has been included in the criteria by the Musculoskeletal Infection Society in 2018 as a novel parameter to diagnose prosthetic joint infection (PJI). However, it is unclear how D-dimer levels change in between stages of a two-stage exchange. We prospectively investigated 30 patients who underwent a two-stage exchange using a spacer for PJI. D-Dimer, CRP and IL-6 were collected before first and second stage surgery and the difference (Δ) in between stages was calculated. The levels of plasma D-Dimer did not change from first to second stage surgery (2770 ng/ml (IQR, 1600–3770 ng/ml) versus 2340 ng/ml (IQR, 1270–4100 ng/ml); p = 0.8) while CRP (4.0 mg/dl (IQR, 1.7–5.5 mg/dl) versus 0.6 mg/dl (IQR, 0.5–0.8 mg/dl); p < 0.001) and IL-6 (21 pg/ml (IQR, 10–29 pg/ml) versus 6 pg/ml (4–9 pg/ml); p < 0.001) decreased. The ΔD-dimer between both stages was 300 ng/ml (range: − 2820 to 4280 ng/ml), the median ΔCRP was − 3.4 mg/dl (IQR, − 1.2 to − 4.8 mg/dl) and ΔIL-6 was − 13 pg/ml (IQR, − 4 to − 20 pg/ml). In 15 of 30 cases (50%) the D-dimer level increased between both stages, whereas the level of CRP (93%; 28/30) and IL-6 (96%; 28/29) decreased in most patients. As the level of serum D-dimers varies greatly, lacks a uniform decrease and does not identify persisting infection, surgeons should be cautious when using it at the timing of reimplantation.

Fibrinogen performs better than D-dimer for the diagnosis of periprosthetic joint infection: a meta-analysis of diagnostic trials

Purpose

D-dimer and fibrinogen, both belonging to coagulation parameters, are controversial for the diagnosis of periprosthetic joint infection (PJI). This meta-analysis was conducted to compare their diagnostic accuracies for PJI by synthesizing currently available evidence.

Methods

Cochrane Library, MEDLINE, Web of Science, and Embase up to March 1, 2020, and other relevant articles were searched. Five hundred and eighty-one articles were identified after initial research, and 11 studies were included finally. No threshold effects were found between studies. The pooled sensitivity, specificity, and positive and negative likelihood ratio were reported to evaluate the diagnostic performance with heterogeneity analysis. Z test statistics was used to analyze the difference of diagnostic performance between D-dimer and fibrinogen.

Results

The pooled sensitivity, specificity, and positive and negative likelihood ratio of D-dimer for PJI were 0.79 (95% [CI], 0.72–0.85), 0.77 (0.67–0.84), 3.38 (2.21–5.18), and 0.27 (0.18–0.41), respectively. As for fibrinogen, the pooled sensitivity, specificity, and positive and negative likelihood ratio for PJI were 0.75 (0.68–0.80), 0.85 (0.82–0.88), 5.12 (4.22–6.22), and 0.30 (0.23–0.37), respectively. Great heterogeneity was found in studies for D-dimer, and univariate meta-regression analysis revealed that number of involved joints, disease spectrum, comorbidities influencing D-dimer, and sample sources were the source of heterogeneity. Z test found that the pooled specificity of fibrinogen was significantly higher than D-dimer (0.85 ± 0.01 versus 0.77 ± 0.04, p = 0.03). The pooled positive likelihood ratio of fibrinogen was significantly higher than D-dimer (5.12 ± 0.51 versus 3.38 ± 0.74, p = 0.03).

Conclusion

Based on currently available evidence, the meta-analysis suggests that fibrinogen performs better than D-dimer as a rule-in diagnostic tool for its higher specificity. However, more prospective trials with larger size are still needed to provide further confirmation.

Trial registration

This meta-analysis was prospectively registered on PROSPERO (International prospective register of systematic reviews), and the registering number was CRD42020177176.

Analysis of Risk Factors and Clinical Indicators in Bloodstream Infections Among Patients with Hematological Malignancy

Purpose

The incidence of bloodstream infection (BSI) is more common in patients with hematological malignancy. It is important to distinguish infectious episodes from noninfectious episodes. The present study was aimed to describe the epidemiology, clinical indexes, and antibiotic use for in-hospital bloodstream infections of hematological malignancy patients.

Patients and Methods

Single-center retrospective research was performed on hematological malignancy patients admitted to our hospital from July 2015 to March 2018. Laboratory and clinical information from 322 febrile patients were acquired. These episodes were divided by blood culture results into two groups: 1) blood culture positive-group, 2) blood culture negative-group.

Results

In the 322 febrile cases, 81 (25.2%) patients were blood culture positive, and among them, Gram-negative (G-) bacteria (51.9%) were more isolated than Gram-positive (G+) bacteria (32.1%) and fungi (7.4%). Gram-negative bacteria were more likely to have drug resistance than G+ bacteria. Independent risk factors revealed that patients with complications, high levels of procalcitonin (PCT), glucose, interleukin-6 (IL-6), and d-dimer (D-D), and low concentration of albumin were correlated with the occurrence of BSI. PCT, IL-6 and D-D performed well in differentiating the positive group from the negative group. Moreover, IL-6 and D-D showed excellent performance in differentiating G- and G+ groups, with the areas under the curve all above 0.8.

Conclusion

We analyzed the risk factors for BSI in patients with hematological malignancy, the distribution of bacteria, antibiotic resistance, and the changes in clinical parameters. This single-center retrospective study may provide clinicians insight into the diagnosis and treatment of BSI.

Comparing the Diagnostic Value of Serum D-Dimer to CRP and IL-6 in the Diagnosis of Chronic Prosthetic Joint Infection

Introduction: D-dimer is a diagnostic criterion for periprosthetic joint infection (PJI) of the Musculoskeletal Infection Society (MSIS) in 2018. The aim of this study was to evaluate the serum D-dimer values in comparison to C-reactive protein (CRP) and interleukin-6 (IL-6) for the diagnosis of PJI. Materials and Methods: We included 119 patients (50 women, 69 men; 71 knees, 48 hips) undergoing revision arthroplasty with preoperative assessment of CRP, IL-6, and serum D-dimer. Cases were classified as infected or aseptic based on the MSIS criteria of 2018. Receiver operating curves and Youden’s index were used to define an ideal cut-off value and sensitivity and specificity for the individual parameters, and respective combinations were calculated using cross-tables. Results: The median D-dimer level (2320 vs. 1105 ng/mL; p < 0.001), the median CRP level (4.0 vs. 0.5 mg/dL; p < 0.001), and the median IL-6 level (21.0 vs. 5.0 pg/mL; p < 0.001) were significantly higher in the group of PJI compared to the group with aseptic failure. The calculated optimal cut-off values were 2750 ng/mL (AUC 0.767) for D-dimer, 1.2 mg/dL (AUC 0.914) for CRP, and 10.0 pg/mL (AUC 0.849) for IL-6. D-dimer showed a sensitivity of 38% and specificity of 94%, whereas the CRP and IL-6 had sensitivities of 88% and 76%, and specificities of 87% and 92%, respectively. Conclusion: In comparison with CRP and IL-6, serum D-dimer showed low sensitivity and specificity in our cohort. While CRP and IL-6 combination had the highest sensitivity, a combination of Il-6 and D-dimer or CRP and IL-6 had the highest specificity.

Reliability of d-Dimer Determination in Diagnosis of Peri-Prosthetic Joint Infection: A Systematic Review and Meta-Analysis

Background: Surgeons continue to seek indicators for the diagnosis of peri-prosthetic joint infection (PJI), which is a serious complication after total joint arthroplasty (TJA). Many recent studies have assessed the value of d-dimer in diagnosing PJI because of the close relation between the d-dimer value and inflammation. However, the conclusions from different studies are still disputed. Methods: We searched for studies published from 2011 to March 2020 using online databases and screened studies based on the inclusion criteria. Diagnostic parameters of d-dimer, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were calculated, including the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and the area under the curve (AUC). In addition, univariate meta-regression and subgroup analyses were performed to identify sources of heterogeneity. Results: A total of nine studies with 431 Patients with PJI were included. The pooled sensitivity, specificity, DOR, and AUC of d-dimer were 0.82 (95% confidence interval [CI], 0.73-0.89), 0.73 (95% CI, 0.58-0.83), 12 (95% CI, 5-30), and 0.85 (95% CI, 0.82-0.88), respectively. In addition, the sensitivity, specificity, and AUC of CRP were 0.78 (95% CI, 0.73-0.83), 0.80 (95% CI, 0.73-0.86) and 0.85 (95% CI, 0.81-0.87), respectively, whereas those of ESR were 0.68 (95% CI, 0.60-0.74), 0.83 (95% CI, 0.75-0.88), and 0.80 (95% CI, 0.76-0.83), respectively. Conclusions: d-dimer determination had similar performance to CRP and ESR in the diagnosis of PJI and may be a good addition to the current diagnostic criteria.

Diagnostic accuracy of D-dimer in periprosthetic joint infection: a diagnostic meta-analysis

BACKGROUND

Periprosthetic joint infection (PJI) is one of the most devastating complications after total joint replacement (TJA). Up to now, the diagnosis of PJI is still in a dilemma. As a novel biomarker, whether D-dimer is valuable in the diagnosis of PJI remains controversial. This meta-analysis attempts to determine the diagnostic accuracy of D-dimer in PJI.

METHODS

Relevant literature was retrieved from PubMed, Embase, Web of Science, and Cochrane Library (from database establishment to April 2020). Literature quality was evaluated using Revman (version 5.3). The random effect model was used in the Stata version 14.0 software to combine sensitivity, specificity, likelihood ratio (LR), diagnostic odds ratio (DOR), summary receiver operating characteristic (SROC) curve, and area under SROC (AUC) to evaluate the diagnostic value of overall D-dimer for PJI. Meta regression and subgroup analysis were performed according to the threshold, the study design, the sample size, the diagnostic gold standard, the country of study, and the type of sample.

RESULTS

A total of 9 studies were included in this study, including 1592 patients. The pooled sensitivity and specificity of D-dimer for PJI diagnosis are 0.82 (95% CI, 0.72~0.89) and 0.73 (95% CI, 0.58~0.83), respectively. The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 2.99 (95% CI, 1.84~4.88) and 0.25 (95% CI, 0.15~0.41), respectively. The pooled AUC and diagnostic odds ratios were 0.85 (95% CI, 0.82~0.88) and 12.20 (95% CI, 4.98~29.86), respectively.

CONCLUSION

D-dimer is a promising biomarker for the diagnosis of PJI, which should be used in conjunction with other biomarkers or as an adjunct to other diagnostic methods to enhance diagnostic performance.