The Concordance between Preoperative Aspiration and Intraoperative Synovial Fluid Culture Results: Intraoperative Synovial Fluid Re-Cultures Are Necessary whether the Preoperative Aspiration Culture is Positive or Not.

Abstract Aims: Preoperative aspiration culture and intraoperative cultures play pivotal roles in periprosthetic joint infection (PJI) diagnosis and pathogen identification. But the discordance between preoperative aspiration culture and intraoperative synovial fluid culture remains unknown. We aim to determine 1）the discordance between preoperative and intraoperative synovial fluid (SF) culture and. 2) compared to intraoperative synovial fluid cultures, the sensitivity of preoperative aspiration fluid culture. Then the following question is tried to be answered: Are intraoperative synovial fluid re-cultures necessary if the preoperative aspiration culture is positive?Materials and methods:Between 2015 and 2019, 187 PJI patients managed with surgeries were included in this study. Compared to intraoperative synovial fluid culture, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of preoperative aspiration culture were calculated. Then, the discordance between preoperative aspiration culture and intraoperative SF culture was analyzed. Results:The sensitivity of preoperative aspiration culture was 81.29% compared to intraoperative synovial fluid cultures. Concordance was identified in 147 PJI (78.61%) patients and culture discordance occurred in 40 patients (21.39%). In these discordant PJI patients, 24 patients (60%) were polymicrobial and no intraoperative synovial fluid culture growth was found in 16 PJI cases (40%). Preoperative monomicrobial staphylococcus results had a sensitivity of and a specificity of 80.43% and 83.16%, respectively. Preoperative polymicrobial results had the lowest sensitivity.Conclusions: The intraoperative synovial fluid re-cultures are necessary if the preoperative aspiration culture is positive and the discordance between preoperative aspiration culture and intraoperative synovial fluid culture should be noted especially when streptococcus spp. and more than one pathogen was revealed by preoperative aspiration culture.

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The concordance between preoperative aspiration and intraoperative synovial fluid culture results: intraoperative synovial fluid re-cultures are necessary whether the preoperative aspiration culture is positive or not

BMC Infectious Diseases ◽

10.1186/s12879-021-06721-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Hao Li ◽

Chi Xu ◽

LiBo Hao ◽

Wei Chai ◽

Fu Jun ◽

...

Keyword(s):

Synovial Fluid ◽

Positive Predictive Value ◽

Predictive Value ◽

Joint Infection ◽

Pathogen Identification ◽

Level Of Evidence ◽

Culture Growth ◽

Sensitivity Specificity ◽

Synovial Fluid Culture ◽

Fluid Culture

Abstract Aims Preoperative aspiration culture and intraoperative cultures play pivotal roles in periprosthetic joint infection (PJI) diagnosis and pathogen identification. But the discordance between preoperative aspiration culture and intraoperative synovial fluid culture remains unknown. We aim to determine (1) the discordance between preoperative and intraoperative synovial fluid (SF) culture and. (2) compared to intraoperative synovial fluid cultures, the sensitivity of preoperative aspiration fluid culture. Then the following question is tried to be answered: Are intraoperative synovial fluid re-cultures necessary if the preoperative aspiration culture is positive? Materials and methods Between 2015 and 2019, 187 PJI patients managed with surgeries were included in this study. Compared to intraoperative synovial fluid culture, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of preoperative aspiration culture were calculated. Then, the discordance between preoperative aspiration culture and intraoperative SF culture was analyzed. Results The sensitivity of preoperative aspiration culture was 81.29% compared to intraoperative synovial fluid cultures. Concordance was identified in 147 PJI (78.61%) patients and culture discordance occurred in 40 patients (21.39%). In these discordant PJI patients, 24 patients (60%) were polymicrobial and no intraoperative synovial fluid culture growth was found in 16 PJI cases (40%). Preoperative monomicrobial staphylococcus results had a sensitivity of and a specificity of 80.43% and 83.16%, respectively. Preoperative polymicrobial results had the lowest sensitivity. Conclusions The intraoperative synovial fluid re-cultures are necessary if the preoperative aspiration culture is positive and the discordance between preoperative aspiration culture and intraoperative synovial fluid culture should be noted especially when Streptococcus spp. and more than one pathogen was revealed by preoperative aspiration culture. Level of evidence: Level III.

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Preoperative synovial fluid culture poorly predicts the pathogen causing periprosthetic joint infection

Infection ◽

10.1007/s15010-020-01540-2 ◽

2020 ◽

Author(s):

Philipp Schulz ◽

Constantin E. Dlaska ◽

Carsten Perka ◽

Andrej Trampuz ◽

Nora Renz

Keyword(s):

Synovial Fluid ◽

Periprosthetic Joint Infection ◽

Detection Rate ◽

Pathogen Detection ◽

Joint Infection ◽

Coagulase Negative Staphylococci ◽

Exact Test ◽

Culture Positive ◽

Synovial Fluid Culture ◽

Polymicrobial Infections

Abstract Purpose We investigated the value of preoperative pathogen detection and evaluated its concordance with intraoperative cultures in patients with culture-positive periprosthetic joint infection (PJI). Methods Culture-positive PJI episodes with available preoperative (synovial fluid) and intraoperative cultures (periprosthetic tissue, synovial or sonication fluid) were analyzed. The pathogen detection rate in preoperative and intraoperative cultures was compared using Fisher’s exact test and their concordance was calculated. Results Among 167 included PJI episodes, 150 were monomicrobial with coagulase-negative staphylococci (n = 55, 37%), S. aureus (n = 34, 23%), and streptococci (n = 21, 14%) being the most common pathogens. Seventeen episodes (10%) were polymicrobial infections. The pathogen(s) grew in preoperative culture in 110 and in intraoperative cultures in 153 episodes (66% vs. 92%, p < 0.001). The pathogen detection rate was lower in preoperative compared to intraoperative cultures for low-virulent pathogens (40% vs. 94%, p < 0.001), polymicrobial infections (59% vs. 100%, p = 0.007), and in delayed and late PJI (63% vs. 94%, and 66% vs. 91%, respectively, p < 0.001). Full concordance of preoperative and intraoperative cultures was found in 87 episodes (52%). The pathogen was detected solely preoperatively in 14 episodes (8%) and solely intraoperatively in 57 cases (34%); an additional pathogen was found in 3 episodes (2%) preoperatively and in 6 episodes (4%) intraoperatively. Conclusion The concordance of preoperative and intraoperative cultures was poor (52%). The sole or an additional pathogen was found exclusively in intraoperative cultures in 38% of PJI episodes, hence preoperative synovial fluid cultures are considered unreliable for pathogen detection in PJI.

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New Methods in the Diagnosis of Prosthetic Joint Infection

Traumatology and Orthopedics of Russia ◽

10.21823/2311-2905-2019-25-4-56-63 ◽

2019 ◽

Vol 25 (4) ◽

pp. 56-63

Author(s):

S. Karbysheva ◽

N. Renz ◽

K. Yermak ◽

S. Cabric ◽

A. Trampuz

Keyword(s):

Synovial Fluid ◽

Multiplex Pcr ◽

Sensitivity And Specificity ◽

Leukocyte Count ◽

Joint Infection ◽

Accurate Diagnosis ◽

Confirmatory Test ◽

New Methods ◽

Synovial Fluid Culture ◽

Fluid Culture

A timely and accurate diagnosis of periprosthetic joint infection (PJI) is crucial to plan adequate treatment. Purpose of the study. To evaluate the performance of new diagnostic tests for the diagnosis of PJI. Material and Methods. The performance of novel biomarkers in synovial fluid (i.e. D-lactate and alfa-defensin), molecular test (i.e. PCR of synovial fluid and sonication fluid), new methods to dislodge biofilm from implant surface (i.e. MicroDTTect) and sonication of explanted prosthesis were investigated in patients with PJI and aseptic loosening of the prosthesis. Results. D-lactate showed better sensitivity for the diagnosis of PJI compared to leukocyte count (86% and 80%, respectively). The optimal D-lactate cut-off value was calculated at 1.26 mmol/l. The ADLF test showed sensitivity of 84%, 67% and to 54% depending on classification criteria used for the diagnosis of PJI (Musculoskeletal Infection Society (MSIS), The Infectious Diseases Society of America (IDSA) and proposed European Bone and Joint Infection Society (EBJIS) criteria, respectively). Using the proposed EBJIS definition criteria, the sensitivity of the leukocyte count was significantly higher than that of the ADLF test (86% compared with 54%; p<0,001), particularly in chronic PJI (81% compared with 44%, respectively; p<0,001). The sensitivity of synovial fluid PCR was 60% and herewith comparable with synovial fluid culture (52%, p = 0,239). The sensitivity and specificity of sonication fluid culture were 58% and 100%, which was comparable to sonication fluid PCR 51% and 94%, respectively. DTT-based method showed low sensitivity for diagnosis of PJI (40%) compared to sonication (80%, p<0,01). Conclusion. Synovial fluid D-lactate demonstrated good analytical performance and diagnostic value for the diagnosis of PJI. In particular, the high sensitivity for diagnosing infection and rapid availability of the test result make synovial fluid D-lactate suitable as screening test, whereas ADLF had limited sensitivity (54%) but high specificity (>95%) and it should therefore not be used for screening, but rather as a confirmatory test for PJI. Multiplex PCR of synovial fluid and sonication fluid has similar sensitivity and specificity compared to synovial fluid culture, having the advantage of rapid availability of results (within 5 hours) and fully automated process. With further improvement of its performance and inclusion of additional primers, multiplex PCR may complement conventional cultures, especially for rapid and accurate diagnosis of low-grade PJI. Culture of samples obtained by sonication of prostheses showed better sensitivity for the microbiologic diagnosis of prosthetic hip and knee infection compared to chemical based dislodgement such as MicroDTTect.

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Reliability of synovial fluid alpha-defensin and leukocyte esterase in diagnosing periprosthetic joint infection (PJI): a systematic review and meta-analysis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-019-1395-3 ◽

2019 ◽

Vol 14 (1) ◽

Cited By ~ 10

Author(s):

Yisheng Chen ◽

Xueran Kang ◽

Jie Tao ◽

Yunpeng Zhang ◽

Chenting Ying ◽

...

Keyword(s):

Systematic Review ◽

Synovial Fluid ◽

Periprosthetic Joint Infection ◽

Meta Analysis ◽

Joint Infection ◽

High Specificity ◽

Diagnostic Efficiency ◽

Operating Characteristics ◽

Musculoskeletal Infection ◽

Sensitivity Specificity

Abstract Background Synovial fluid proteins had been applied as diagnostic biomarkers for periprosthetic joint infection (PJI) in recent research papers. Thus, this meta-analysis aimed to estimate the diagnostic efficiency of synovial fluid α-defensin and leukocyte esterase (LE) for PJI. Methods We conducted our systematic review by searching the keywords in online databases such as PubMed, Embase, Cochrane, Elsevier, Springer, and Web of Science from the time of database inception to October 2018. Inclusion criteria were as follows: patients who have undergone knee, hip, or shoulder joint replacements; α-defensin or leukocyte esterase (LE strip) of synovial fluid was detected as the biomarker for PJI diagnosis; and Musculoskeletal Infection Society (MSIS) or utilizing a combination of clinical data was considered as the gold standard. Diagnostic parameters including sensitivity, specificity, diagnostic odds ratio (DOR), and area under the summary of receiver operating characteristics curve (AUSROC) were calculated for the included studies to evaluate the synovial fluid α-defensin and LE for PJI diagnosis. Results After full-text review, 28 studies were qualified for this systematic review, 16 studies used α-defensin and the other 12 were conducted using LE strip. The pooled sensitivity, specificity, and DOR of LE strip were 87% (95% CI 84–90%), 96% (95% CI 95–97%), and 170.09 (95% CI 97.63–296.32), respectively, while the pooled sensitivity, specificity, and DOR of α-defensin were 87% (95% CI 83–90%), 97% (95% CI 96–98%), and 158.18 (95% CI 74.26–336.91), respectively. The AUSROC for LE strip and α-defensin were 0.9818 and 0.9685, respectively. Conclusion Both LE strip and α-defensin of synovial fluid provide rapid and convenient diagnosis for PJI. Sensitivity of α-defensin and LE strip are the same, while both these two methods have high specificity in clinical practice.

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Synovial Fluid Aspiration Should Not Be Routinely Performed during the Two-Stage Exchange of the Knee

BioMed Research International ◽

10.1155/2018/6720712 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Sebastian P. Boelch ◽

Magnus Roth ◽

Joerg Arnholdt ◽

Maximilian Rudert ◽

Martin Luedemann

Keyword(s):

Synovial Fluid ◽

Blood Cell ◽

Sensitivity And Specificity ◽

Pathogen Detection ◽

Joint Infection ◽

Youden Index ◽

Blood Cell Count ◽

Two Stage ◽

Synovial Fluid Culture ◽

Fluid Culture

Purpose. Detection of infection persistence during the two-stage exchange of the knee for periprosthetic joint infection is challenging. Synovial fluid culture (SFC) and synovial white blood cell count (SWBCC) before joint reimplantation are widespread diagnostic means for this indication. The sensitivity and specificity of SFC and of SWBCC for infection persistence before planned reimplantation were evaluated. Methods. 94 two-stage exchanges of the knee with synovial fluid aspiration performed after a drug holiday of at least 14 days and before reimplantation or spacer exchange (planned reimplantation) were retrospectively analyzed. Only cases with at least 3 intraoperative samples at planned reimplantation were included. SFC and SWBCC were compared to pathogen detection (SFC(culture)/SWBCC(culture)) and to histopathological signs of infection persistence (SFC(histo)/SWBCC(histo)) from intraoperative samples at planned reimplantation. For SFC, the sensitivity and specificity were calculated. For SWBCC, the optimal cut-off value with its sensitivity and specificity was calculated with the Youden-Index. Results. Sensitivity and specificity of SFC(culture) were 0.0% and 98.9%. Sensitivity and specificity of SFC(histo) were 3.4% and 100%. The optimal cut-off value for SWBCC(culture) was 4450 cells/μl with a sensitivity of 50.0% and a specificity of 86.5%. The optimal cut-off value for SWBCC(histo) was 3250 cells/μl with a sensitivity of 35.7% and a specificity of 92.9%. Conclusion. The detection of infection persistence remains challenging and a consented approach is lacking. The results do not warrant the routine performance of SFC during the two-stage exchange at the knee. SWBCC can be used to confirm infection persistence at high cut-offs, but they only occur in few patients and are therefore inappropriate for the routine use.

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Direct Detection and Identification of Prosthetic Joint Infection Pathogens in Synovial Fluid by Metagenomic Shotgun Sequencing

Journal of Clinical Microbiology ◽

10.1128/jcm.00402-18 ◽

2018 ◽

Vol 56 (9) ◽

Cited By ~ 41

Author(s):

Morgan I. Ivy ◽

Matthew J. Thoendel ◽

Patricio R. Jeraldo ◽

Kerryl E. Greenwood-Quaintance ◽

Arlen D. Hanssen ◽

...

Keyword(s):

Synovial Fluid ◽

Prosthetic Joint Infection ◽

Joint Infection ◽

Shotgun Sequencing ◽

Species Level ◽

Prosthetic Joint ◽

Synovial Fluid Culture ◽

Culture Negative ◽

Aseptic Failure ◽

Fluid Culture

ABSTRACTMetagenomic shotgun sequencing has the potential to transform how serious infections are diagnosed by offering universal, culture-free pathogen detection. This may be especially advantageous for microbial diagnosis of prosthetic joint infection (PJI) by synovial fluid analysis since synovial fluid cultures are not universally positive and since synovial fluid is easily obtained preoperatively. We applied a metagenomics-based approach to synovial fluid in an attempt to detect microorganisms in 168 failed total knee arthroplasties. Genus- and species-level analyses of metagenomic sequencing yielded the known pathogen in 74 (90%) and 68 (83%) of the 82 culture-positive PJIs analyzed, respectively, with testing of two (2%) and three (4%) samples, respectively, yielding additional pathogens not detected by culture. For the 25 culture-negative PJIs tested, genus- and species-level analyses yielded 19 (76%) and 21 (84%) samples with insignificant findings, respectively, and 6 (24%) and 4 (16%) with potential pathogens detected, respectively. Genus- and species-level analyses of the 60 culture-negative aseptic failure cases yielded 53 (88%) and 56 (93%) cases with insignificant findings and 7 (12%) and 4 (7%) with potential clinically significant organisms detected, respectively. There was one case of aseptic failure with synovial fluid culture growth; metagenomic analysis showed insignificant findings, suggesting possible synovial fluid culture contamination. Metagenomic shotgun sequencing can detect pathogens involved in PJI when applied to synovial fluid and may be particularly useful for culture-negative cases.

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Synovial fluid interleukin-6 is not superior to cell count and differential in the detection of periprosthetic joint infection

Bone & Joint Open ◽

10.1302/2633-1462.112.bjo-2020-0166.r1 ◽

2020 ◽

Vol 1 (12) ◽

pp. 737-742

Author(s):

René Mihalič ◽

Jurij Zdovc ◽

Peter Brumat ◽

Rihard Trebše

Keyword(s):

Synovial Fluid ◽

Periprosthetic Joint Infection ◽

Joint Infection ◽

Predictive Performance ◽

Sinus Tract ◽

Histopathological Analysis ◽

Polymorphonuclear Cells ◽

Level Of Evidence ◽

Wbc Count ◽

Sensitivity Specificity

Aims Synovial fluid white blood cell (WBC) count and percentage of polymorphonuclear cells (%PMN) are elevated at periprosthetic joint infection (PJI). Leucocytes produce different interleukins (IL), including IL-6, so we hypothesized that synovial fluid IL-6 could be a more accurate predictor of PJI than synovial fluid WBC count and %PMN. The main aim of our study was to compare the predictive performance of all three diagnostic tests in the detection of PJI. Methods Patients undergoing total hip or knee revision surgery were included. In the perioperative assessment phase, synovial fluid WBC count, %PMN, and IL-6 concentration were measured. Patients were labeled as positive or negative according to the predefined cut-off values for IL-6 and WBC count with %PMN. Intraoperative samples for microbiological and histopathological analysis were obtained. PJI was defined as the presence of sinus tract, inflammation in histopathological samples, and growth of the same microorganism in a minimum of two or more samples out of at least four taken. Results In total, 49 joints in 48 patients (mean age 68 years (SD 10; 26 females (54%), 25 knees (51%)) were included. Of these 11 joints (22%) were infected. The synovial fluid WBC count and %PMN predicted PJI with sensitivity, specificity, accuracy, PPV, and NPV of 82%, 97%, 94%, 90%, and 95%, respectively. Synovial fluid IL-6 predicted PJI with sensitivity, specificity, accuracy, PPV, and NPV of 73%, 95%, 90%, 80%, and 92%, respectively. A comparison of predictive performance indicated a strong agreement between tests. Conclusions Synovial fluid IL-6 is not superior to synovial fluid WBC count and %PMN in detecting PJI. Level of Evidence: Therapeutic Level II Cite this article: Bone Jt Open 2020;1-12:737–742.

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Synovial Complement Factors in Patients with Periprosthetic Joint Infection after Undergoing Revision Arthroplasty of the Hip or Knee Joint

Diagnostics ◽

10.3390/diagnostics11030434 ◽

2021 ◽

Vol 11 (3) ◽

pp. 434

Author(s):

Frank Sebastian Fröschen ◽

Sophia Schell ◽

Matthias Dominik Wimmer ◽

Gunnar Thorben Rembert Hischebeth ◽

Hendrik Kohlhof ◽

...

Keyword(s):

Synovial Fluid ◽

Multiple Regression ◽

Complement System ◽

Periprosthetic Joint Infection ◽

Joint Infection ◽

Expression Patterns ◽

Factor H ◽

Low Grade ◽

Complement Factors ◽

Fluid Levels

The role and diagnostic value of the synovial complement system in patients with low-grade periprosthetic joint infection (PJI) are unclear. We sought to evaluate, for the first time, the usefulness of synovial complement factors in these patients by measuring the individual synovial fluid levels of complement factors (C1q, C3b/iC3b, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, properdin, and mannose-binding lectin [MBL]). The patients (n = 74) were classified into septic (n = 28) and aseptic (n = 46). Receiver-operator characteristic curves and a multiple regression model to determine the feasibility of a combination of the tested cytokines to determine the infection status were calculated. The synovial fluid levels of C1q, C3b/C3i, C4b, C5, C5a, MBL, and properdin were significantly elevated in the PJI group. The best sensitivity and specificity was found for C1q. The multiple regression models revealed that the combination of C1q, C3b/C3i, C4b, C5, C5a, and MBL was associated with the best sensitivity (83.3%) and specificity (79.2%) for a cutoff value of 0.62 (likelihood ratio: 4.0; area under the curve: 0.853). Nevertheless, only a combined model showed acceptable results. The expression patterns of the complement factors suggested that PJI activates all three pathways of the complement system.

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Foundational Statistical Principles in Medical Research: Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value

Medicina ◽

10.3390/medicina57050503 ◽

2021 ◽

Vol 57 (5) ◽

pp. 503

Author(s):

Thomas F. Monaghan ◽

Syed N. Rahman ◽

Christina W. Agudelo ◽

Alan J. Wein ◽

Jason M. Lazar ◽

...

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Medical Literature ◽

Disease Prevalence ◽

Positive Test Result ◽

Predictive Values ◽

Sensitivity Specificity ◽

Test Result ◽

Test Probability

Sensitivity, which denotes the proportion of subjects correctly given a positive assignment out of all subjects who are actually positive for the outcome, indicates how well a test can classify subjects who truly have the outcome of interest. Specificity, which denotes the proportion of subjects correctly given a negative assignment out of all subjects who are actually negative for the outcome, indicates how well a test can classify subjects who truly do not have the outcome of interest. Positive predictive value reflects the proportion of subjects with a positive test result who truly have the outcome of interest. Negative predictive value reflects the proportion of subjects with a negative test result who truly do not have the outcome of interest. Sensitivity and specificity are inversely related, wherein one increases as the other decreases, but are generally considered stable for a given test, whereas positive and negative predictive values do inherently vary with pre-test probability (e.g., changes in population disease prevalence). This article will further detail the concepts of sensitivity, specificity, and predictive values using a recent real-world example from the medical literature.

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