Publications by authors named "Rihard Trebše"

41 Publications

Evaluation and interpretation of prosthetic joint infection diagnostic investigations.

Int Orthop 2021 04 8;45(4):847-855. Epub 2021 Feb 8.

Valdoltra Orthopaedic Hospital, Jadranska cesta 31, SI-6280, Ankaran, Slovenia.

Background: Total joint arthroplasty (TJA) is considered one of the most successful surgical procedures ever developed. It can successfully provide pain relief, restore joint function, and improve mobility and quality of life. Prosthetic joint infection (PJI) presents with a wide variety and severity of signs and symptoms. It remains a major threat to the outcome of TJA procedures and usually necessitates surgical intervention and prolonged courses of antibiotics. Inappropriate treatment of an unrecognized PJI usually ends with unacceptable and sometimes catastrophic results.

The Aim: The understanding and evaluation of diagnostic investigations are extremely important to properly diagnose PJI, including frequently unrecognized low-grade infections, and to provide healthcare professionals with needed information for the care of patients affected by this condition. This article aims to review most of the methods available in PJI diagnostics, to emphasize the strengths and the weaknesses of each of them, and to provide a guideline on how to select the surgical treatment strategy based on the level of diagnostic certainty during the evaluation period. To safely accomplish this, it is crucial to be aware of the limitations of each diagnostic modality.

The Focus: The emphasis will be on the use and interpretation of the core criteria for PJI diagnosis, including the pathognomonic sinus tract communicating with the implant, purulent synovial fluid, inflammation in the periprosthetic tissue, cell count with differential, microbial growth in the synovial fluid culture, tissue sample cultures, and sonication samples.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00264-021-04958-xDOI Listing
April 2021

Bernese peri-acetabular osteotomy performed with navigation and patient-specific templates is a reproducible and safe procedure.

Int Orthop 2021 04 11;45(4):883-889. Epub 2021 Jan 11.

Valdoltra Orthopaedic Hospital, Jadranska cesta 31, 6280, Ankaran, Slovenia.

Purpose: To present a novel surgical technique for the Bernese peri-acetabular osteotomy (PAO) using electromagnetic navigation (EMN) and patient-specific templates (PST), and to evaluate it against the traditional fluoroscopic technique.

Methods: We included 40 dysplastic hips. All PAOs were performed using PST and EMN. We recorded learning-related complications. For the purpose of acetabular fragment correction analysis, patients were divided into two groups. In the study group (EMN group, 30 hips), the acetabular fragment was reoriented with the help of EMN. In the control group (XR group, 10 hips), the acetabular fragment was reoriented using fluoroscopy. We compared the difference between the planned and achieved position of the acetabular fragment and outcomes between both groups.

Results: Two major complications occurred in four PAOs in the XR group only (first ten PAOs). The average absolute difference in planned and achieved lateral centre -edge angle (LCEA) and acetabular index (AI) was 1.2° ± 1.5° and 1.1° ± 2° for the EMN and 7° ± 6.1° and 6.3° ± 6.3° for the XR group (p = 0.02; p = 0.03). The average surgery duration was 183 ± 32 minutes for the EMN and 203 ± 42 minutes for the XR group (p = 0.19). At the last follow-up, the average Harris Hip Score (HHS) value was 88 ± 12 in the EMN and 86 ± 14 in the XR group (p = 0.84).

Conclusions: Our study indicates that PAO performed with EMN and PST seems to be a safe and reproducible procedure with a short learning curve. Additionally, navigated reorientation of the acetabular fragment is significantly more accurate than the fluoroscopic technique.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00264-020-04897-zDOI Listing
April 2021

The EBJIS definition of periprosthetic joint infection.

Bone Joint J 2021 Jan;103-B(1):18-25

Orthopaedic Hospital Valdoltra, Ankaran, Slovenia.

Aims: The diagnosis of periprosthetic joint infection (PJI) can be difficult. All current diagnostic tests have problems with accuracy and interpretation of results. Many new tests have been proposed, but there is no consensus on the place of many of these in the diagnostic pathway. Previous attempts to develop a definition of PJI have not been universally accepted and there remains no reference standard definition.

Methods: This paper reports the outcome of a project developed by the European Bone and Joint Infection Society (EBJIS), and supported by the Musculoskeletal Infection Society (MSIS) and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Implant-Associated Infections (ESGIAI). It comprised a comprehensive review of the literature, open discussion with Society members and conference delegates, and an expert panel assessment of the results to produce the final guidance.

Results: This process evolved a three-level approach to the diagnostic continuum, resulting in a definition set and guidance, which has been fully endorsed by EBJIS, MSIS, and ESGIAI.

Conclusion: The definition presents a novel three-level approach to diagnosis, based on the most robust evidence, which will be useful to clinicians in daily practice. Cite this article: 2021;103-B(1):18-25.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1302/0301-620X.103B1.BJJ-2020-1381.R1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954183PMC
January 2021

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

Bone Jt Open 2020 Dec 7;1(12):737-742. Epub 2020 Dec 7.

Service for Bone Infections, Valdoltra Orthopaedic Hospital, Ankaran, Slovenia.

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 IICite this article: 2020;1-12:737-742.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1302/2633-1462.112.BJO-2020-0166.R1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750741PMC
December 2020

The impact of surgical strategy and rifampin on treatment outcome in Cutibacterium periprosthetic joint infections.

Clin Infect Dis 2020 Dec 10. Epub 2020 Dec 10.

Department of Medical Microbiology and Infection Prevention, University of Groningen, University Medical Center Groningen, the Netherlands.

Background: Cutibacterium species are common pathogens in periprosthetic joint infections (PJI). These infections are often treated with β-lactams or clindamycin as monotherapy, or in combination with rifampin. Clinical evidence supporting the value of adding rifampin for treatment of Cutibacterium PJI is lacking.

Materials/methods: In this multicenter retrospective study, we evaluated patients with Cutibacterium PJI. The primary endpoint was clinical success, defined by the absence of infection relapse or new infection within a minimal follow-up of 12 months. We used Fisher's exact tests and Cox proportional hazards models to analyze the effect of rifampin and other factors on clinical success after PJI.

Results: We included 187 patients (72.2% male, median age 67 years) with a median follow-up of 36 months. The surgical intervention was two-stage exchange in 95 (50.8%), one-stage exchange in 51 (27.3%), debridement and implant retention (DAIR) in 34 (18.2%), and explantation without reimplantation in 7 (3.7%). Rifampin was included in the antibiotic regimen in 81 (43.3%) cases. Infection relapse occurred in 28 (15.0%), and new infection in 13 (7.0%) cases. In the time-to-event analysis, DAIR (adjusted HR=2.15, p=0.03) and antibiotic treatment over 6 weeks (adjusted HR=0.29, p=0.0002) significantly influenced treatment failure. We observed a tentative evidence for a beneficial effect of adding rifampin to the antibiotic treatment - though not statistically significant for treatment failure (adjusted HR=0.5, p=0.07) and not for relapses (adjusted HR=0.5, p=0.10).

Conclusions: We conclude that a rifampin combination is not markedly superior in Cutibacterium PJI but a dedicated prospective multicenter study is needed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/cid/ciaa1839DOI Listing
December 2020

A novel concept of cam-type femoroacetabular impingement treatment with patient-specific template guided osteochondral deformity ablation.

Int Orthop 2021 04 23;45(4):907-913. Epub 2020 Nov 23.

Valdoltra Orthopaedic Hospital, Jadranska cesta 31, 6280, Ankaran, Slovenia.

Purpose: To present a novel surgical concept for the cam-type femoroacetabular impingement (FAI) treatment and to assess and report the clinical outcomes.

Methods: We performed a retrospective study of a single-surgeon case series of six hips in five consecutive male patients with symptomatic cam-type FAI, treated with the mini-open anterior hip approach with a patient-specific template (PST)-guided deformity ablation between 2015 and 2018. We assessed the hip range of motion, iHOT-33, Tegner, and EQ-5D before surgery and after a minimum follow-up of 30 months.

Results: The average age was 37 ± 13.3 years, average BMI was 31.1 ± 3.3 kg/m, and average pre-surgery Tönnis hip osteoarthritis (OA) grade was 1 ± 1. The average surgery duration was 71 ± eight minutes. The average estimated blood loss was 83 ± 26 ml. After a mean follow-up of 50 ± 12 months, we observed no OA progression with no change in Tönnis hip OA grades. Hip flexion and internal rotation significantly improved (p = 0.007; p = 0.048) from mean 98° ± 9° and 14° ± 11° to mean 113° ± 8° and 23° ± 8°, respectively. iHOT-33, Tegner, and EQ-5D improved significantly (p = < 0.001; p = 0.004; p = < 0.001) from mean 44.7 ± 12.2, 3 ± 1, and 0.513420 ± 0.101389 to mean 94 ± 2.7, 5 ± 1, and 1.000000 ± 0, respectively. One patient needed revision surgery for heterotopic ossification removal, with no sequelae at the last follow-up.

Conclusion: Mini-open anterior hip approach with the PST-guided cam-type FAI deformity ablation presents an accurate and reproducible solution for cam-type FAI surgical treatment, with promising clinical outcomes. Using a PST in the cam-type FAI surgery may present a powerful additional tool in the existing open techniques armamentarium.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00264-020-04887-1DOI Listing
April 2021

Survival rate of total hip replacements with matched and with mixed components with 10.7 years mean follow-up.

Hip Int 2020 Nov 19:1120700020972710. Epub 2020 Nov 19.

Valdoltra Orthopaedic Hospital, Ankaran, Slovenia.

Background: Mixing and matching components from different manufacturers in total hip arthroplasty is a frequently used off-label praxis. The clinical consequences of this procedure have not been studied in detail.

Methods: 860 patients with matched and 1067 patients with mixed primary total hip replacement (THR) components carried out between 1 January 2002 and 31 December 2004, were selected from our Institution registry. The analysis endpoint was set at 1 January 2016. THRs with poorly performing components were excluded from study groups. Kaplan-Meier survival curves for both groups were calculated and compared using the Log-Rank test and the demographic data using the chi-square test. Correlations between demographic data and revisions were calculated using bivariate correlation.

Results: 28 revisions were carried out in the matched group and 67 in the mixed group. The 14-year overall survival probability was significantly better in the former (96.0%) than in the mixed group (92.7%) ( = 0.002). Survival, free of aseptic and septic failures, was statistically, significantly higher in the matched group ( = 0.026 and  = 0.007, respectively).The survival of the mixed subgroup with heads and stems from the same manufacturer did not differ statistically from that of the matched group ( = 0.079).

Conclusions: In contrast to the results listed in the National Joint Registry and the New Zealand Joint Registry, the survival probability in our study was, statistically, significantly higher in total hip replacements using components of the same manufacturer. Importantly, mixing and matching the components of different manufacturers led to similar survival providing the head and the stem were from the same manufacturer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1120700020972710DOI Listing
November 2020

Massive Heterotopic Ossification of the Tensor Fascia Lata in a Bodybuilder Leading to Severe Hip Dysfunction: A Case Report.

JBJS Case Connect 2020 Jul-Sep;10(3):e1900581

1Valdoltra Orthopaedic Hospital, Ankaran, Slovenia 2Faculty of Medicine, University of Maribor, Maribor, Slovenia.

Case: A 42-year-old bodybuilder with no history of trauma presented to our clinic with persistent right hip pain and rapidly advancing joint stiffness. Imaging confirmed massive, mature heterotopic ossification predominantly involving the right tensor fascia lata. Six months after a tailored surgical removal, there were no signs of disability, pain, or clinical signs of recurrence, and the patient regained proper joint function.

Conclusion: In massive heterotopic ossification, tailored surgical removal of the part of the lesion that is limiting function may result in a complete functional recovery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2106/JBJS.CC.19.00581DOI Listing
April 2021

How to handle concomitant asymptomatic prosthetic joints during an episode of hematogenous PJI, a multicentre analysis.

Clin Infect Dis 2020 Aug 18. Epub 2020 Aug 18.

Service of Infectious Diseases, Hospital Clínic, University of Barcelona, Barcelona, Spain.

Introduction: Prosthetic joints are at risk of becoming infected during an episode of bacteremia, especially during S. aureus bacteremia. However, it is unclear how often asymptomatic PJI occurs and whether additional diagnostics should be considered.

Methods: In this multicenter study, we retrospectively analyzed a cohort of patients with a late acute (hematogenous) PJI between 2005-2015 who had concomitant prosthetic joints in situ. Patients without at least 1 year of follow -up were excluded.

Results: 91 patients with a hematogenous PJI and 108 concomitant prosthetic joints were included. The incident PJI was most frequently caused by Staphylococcus aureus (43%), followed by streptococci (26%) and Gram negative rods (18%). Of 108 concomitant prosthetic joints, 13 were symptomatic, of which 10 were subsequently diagnosed as a second PJI. Of the 95 asymptomatic prosthetic joints, 1 PJI developed during the follow-up period and was classified as a 'missed' PJI at the time of bacteremia with S. aureus (1.1%). Infected prosthetic joints were younger than the non-infected ones in 67% of cases, and prosthetic knees were affected more often than prosthetic hips (78%).

Conclusion: During an episode of hematogenous PJI, concomitant asymptomatic prosthetic joints have a very low risk of being infected, and additional diagnostic work-up for these joints is not necessary.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/cid/ciaa1222DOI Listing
August 2020

Reactive Arthritis Provoked by Campylobacter jejuni Enterocolitis Mimicking Prosthetic Joint Infection: A Case Report.

JBJS Case Connect 2020 Jul-Sep;10(3):e2000043

1Service for Bone Infections, Valdoltra Orthopaedic Hospital, Ankaran, Slovenia.

Case: A 59-year-old man with previously well-functioning partial knee replacement was admitted with a warm, swollen, and painful knee. The clinical presentation was consistent with prosthetic joint infection (PJI), but the synovial fluid analysis was negative for microbial growth. Further discussion revealed earlier Campylobacter jejuni enterocolitis that subsequently provoked reactive arthritis (ReA) mimicking PJI. The patient was treated with oral naproxen and intra-articular injection of triamcinolone and recovered completely without antibiotics or surgery. After 29 months, the knee is functioning normally.

Conclusion: ReA is rare but should be included in the differential diagnosis of PJI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2106/JBJS.CC.20.00043DOI Listing
April 2021

Electromagnetic navigation system for acetabular component placement in total hip arthroplasty is more precise and accurate than the freehand technique: a randomized, controlled trial with 84 patients.

Acta Orthop 2020 12 1;91(6):675-681. Epub 2020 Jul 1.

Valdoltra Orthopaedic Hospital, Ankaran.

Background and purpose - The accuracy of conventional navigation systems depends on precise registration of bony landmarks. We investigated the clinical use of electromagnetic navigation (EMN), with a unique device for precise determination of the anterior pelvic plane. Patients and methods - We randomly allocated patients scheduled for total hip arthroplasty into 2 groups of 42 patients each. In the study group, cups were placed at the predetermined target angles (inclination: 42.5°; anteversion: 15°) with the support of EMN. In the control group, cups were placed freehand aiming at the same target angles. Postoperatively the true position of the cup was determined using computed tomography scan of the pelvis. Precision (root mean squared error, RMSE) bias (mean bias error, ME), accuracy, and duration of surgery were compared between the methods. Results - Cup anteversion was more accurate and precise in the navigated group. The ME in the navigated and freehand group was -1.7° (95% CI -2.4 to 1.1) and -4.5° (CI -6.5 to 2.5), respectively. The RMSE in the navigated and freehand group was 2.8° (CI 2.3-3.2) and 8.0° (CI 6.3-9.5), respectively. The inclination was also more precise in the navigated group, with the RMSE in the navigated and freehand group at 4.6° (CI 3.4-5.9) and 6.5° (CI 5.4-7.5), respectively. The accuracy of the inclination and the duration of surgeries were similar between the groups. Interpretation - Cup placement with the help of EMN is more precise than the freehand technique and it does not affect the duration of surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/17453674.2020.1783073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8023939PMC
December 2020

Comprehensive analysis of skeletal muscle- and bone-derived mesenchymal stem/stromal cells in patients with osteoarthritis and femoral neck fracture.

Stem Cell Res Ther 2020 04 3;11(1):146. Epub 2020 Apr 3.

University of Ljubljana, Faculty of Pharmacy, Chair of Clinical Biochemistry, Askerceva 7, 1000, Ljubljana, Slovenia.

Background: Mesenchymal stem/stromal cells (MSCs) can replenish the aged cells of the musculoskeletal system in adult life. Stem cell exhaustion and decrease in their regenerative potential have been suggested to be hallmarks of aging. Here, we investigated whether muscle- and bone-derived MSCs of patients with osteoarthritis and osteoporosis are affected by this exhaustion, compared to healthy donors.

Methods: Patients with primary osteoarthritis, femoral neck fractures due to osteoporosis, and healthy donors (controls) were included. MSCs were isolated from the skeletal muscle and subchondral bone from each patient and compared using ex vivo and in vitro analyses, including immunophenotyping, colony-forming unit fibroblast assays, growth kinetics, cell senescence, multilineage potential, and MSC marker gene expression profiling.

Results: Freshly isolated cells from muscle from patients with osteoarthritis showed a lower proportion of CD45/CD19/CD14/CD34-negative cells compared to patients with osteoporosis and healthy donors. Freshly isolated muscle cells from patients with osteoarthritis and osteoporosis also showed higher clonogenicity compared to healthy donors. MSCs from both tissues of osteoarthritis patients showed significantly reduced osteogenesis and MSCs from the bone also reduced adipogenesis. Chondrogenic pellet diameter was reduced in bone-derived MSCs from both patient groups compared to healthy donors. A significant positive correlation was observed between adipogenesis and CD271 expression in muscle-derived MSCs. CD73 was significantly lower in bone-derived MSCs from osteoarthritis patients, compared to osteoporosis patients. Gene expression profiling showed significantly lower expression of MSC marker gene leptin receptor, LEPR, previously identified as the major source of the bone and adipocytes in the adult bone marrow, in bone-derived MSCs from patients with osteoarthritis in comparison with osteoporotic patients and healthy donors.

Conclusions: Our results show deficient ex vivo and in vitro properties of both skeletal muscle- and bone-derived MSCs in osteoarthritis and osteoporosis patients, compared to healthy donors. In bone-derived MSCs from patients with osteoarthritis, we also identified a lower expression of the leptin receptor, a marker of MSCs that present a major source of MSCs in the adult bone marrow. This suggests that exhaustion of skeletal muscle- and bone-derived MSCs is a hallmark of osteoarthritis and osteoporosis, which defines the need for further clinical trials of stem cell transplantation in these patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13287-020-01657-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7118858PMC
April 2020

Increased Exhaustion of the Subchondral Bone-Derived Mesenchymal Stem/ Stromal Cells in Primary Versus Dysplastic Osteoarthritis.

Stem Cell Rev Rep 2020 08;16(4):742-754

University of Ljubljana, Faculty of Pharmacy, Chair of Clinical Biochemistry, Askerceva 7, 1000, Ljubljana, Slovenia.

Mesenchymal stem/ stromal cell (MSC) exhaustion has been suggested to be a hallmark of aging. Osteoarthritis has a complex etiology that comprises several factors. Dysplasia has been shown to be an individual risk factor for osteoarthritis. Subchondral bone changes are often the first detectable alterations in osteoarthritis. In this study, we aimed to determine whether skeletal MSCs are differentially affected in patients with primary versus dysplastic osteoarthritis. Patients undergoing hip arthroplasty due to primary osteoarthritis (n = 11) and osteoarthritis with hip dysplasia (n = 10) were included in the study. Femoral head subchondral bone was used for isolation of MSCs. The cells were compared using detailed ex-vivo and in-vitro analyses, which included immunophenotyping, colony-forming-unit fibroblast assay, growth kinetics, senescence, multilineage potential, immunophenotyping, and MSC marker-gene expression profiling. Isolated cells from primary osteoarthritis patients showed decreased viability in comparison with those from dysplasia patients, with similar mesenchymal fractions (i.e., CD45/ CD19/ CD14/ CD34-negative cells). In-vitro expanded MSCs from primary osteoarthritis patients showed reduced osteogenic and chondrogenic potential in comparison with dysplasia patients. There were no differences in clonogenicity, growth kinetics, senescence, adipogenic potential, and immunophenotype between these groups. Gene expression profiling showed well-known marker of bone marrow MSCs, the leptin receptor, to be significantly lower for primary osteoarthritis patients. Our study shows that the pathology of primary osteoarthritis is accompanied by bone MSC exhaustion, while biomechanical dysfunction associated with hip dysplasia can induce secondary osteoarthritis without this MSC impairment. Our study suggests that subchondral bone MSC exhaustion is implicated in the pathology of primary osteoarthritis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12015-020-09964-xDOI Listing
August 2020

Lower Success Rate of Débridement and Implant Retention in Late Acute versus Early Acute Periprosthetic Joint Infection Caused by Staphylococcus spp. Results from a Matched Cohort Study.

Clin Orthop Relat Res 2020 06;478(6):1348-1355

M. Wouthuyzen-Bakker, Department of Medical Microbiology and Infection Prevention, University of Groningen, University Medical Center Groningen, the Netherlands.

Background: Surgical débridement, antibiotics and implant retention (DAIR) is currently recommended by international guidelines for both early acute (postsurgical) and late acute (hematogenous) periprosthetic joint infections (PJIs). However, due to a different pathogenesis of infection, a different treatment strategy may be needed.

Questions/purposes: (1) Compared with early acute PJIs, are late acute PJIs associated with a higher risk of DAIR failure? (2) When stratified by microorganism, is the higher risk of failure in late acute PJI associated with Staphylocococcus aureus infection? (3) When analyzing patients with S. aureus infection, what factors are independently associated with DAIR failure?

Methods: In this multicenter observational study, early acute and late acute PJIs treated with DAIR were retrospectively evaluated and matched according to treating center, year of diagnosis, and infection-causing microorganism. If multiple matches were available, the early acute PJI diagnosed closest to the late acute PJI was selected. A total of 132 pairs were included. Treatment success was defined as a retained implant during follow-up without the need for antibiotic suppressive therapy.

Results: Late acute PJIs had a lower treatment success (46% [60 of 132]) compared with early acute PJIs (76% [100 of 132]), OR 3.9 [95% CI 2.3 to 6.6]; p < 0.001), but the lower treatment success of late acute PJIs was only observed when caused by Staphylococcus spp (S. aureus: 34% versus 75%; p < 0.001; coagulase-negative staphylococci: 46% versus 88%; p = 0.013, respectively). On multivariable analysis, late acute PJI was the only independent factor associated with an unsuccessful DAIR when caused by S. aureus (OR 4.52 [95% CI 1.79 to 11.41]; p < 0.001).

Conclusions: Although DAIR seems to be a successful therapeutic strategy in the management of early acute PJI, its use in late acute PJI should be reconsidered when caused by Staphylococcus spp. Our results advocate the importance of isolating the causative microorganism before surgery.

Level Of Evidence: Level III, therapeutic study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CORR.0000000000001171DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7319375PMC
June 2020

Enterococcal periprosthetic joint infection: clinical and microbiological findings from an 8-year retrospective cohort study.

BMC Infect Dis 2019 Dec 27;19(1):1083. Epub 2019 Dec 27.

Center for Musculoskeletal Surgery (CMSC), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.

Background: Treatment of enterococcal periprosthetic joint infections (PJI) is challenging due to non-standardized management strategies and lack of biofilm-active antibiotics. The optimal surgical and antimicrobial therapy are unknown. Therefore, we evaluated characteristics and outcome of enterococcal PJI.

Methods: Consecutive patients with enterococcal PJI from two specialized orthopedic institutions were retrospectively analyzed. Both institutions are following the same diagnostic and treatment concepts. The probability of relapse-free survival was estimated using Kaplan-Meier survival curves and compared by log-rank test. Treatment success was defined by absence of relapse or persistence of PJI due to enterococci or death related to enterococcal PJI. Clinical success was defined by the infection-free status, no subsequent surgical intervention for persistent or perioperative infection after re-implantation and no PJI-related death within 3 months.

Results: Included were 75 enterococcal PJI episodes, involving 41 hip, 30 knee, 2 elbow and 2 shoulder prostheses. PJI occurred postoperatively in 61 episodes (81%), hematogenously in 13 (17%) and by contiguous spread in one. E. faecalis grew in 64 episodes, E. faecium in 10 and E. casseliflavus in one episode(s). Additional microorganism(s) were isolated in 38 patients (51%). Enterococci were susceptible to vancomycin in 73 of 75 isolates (97%), to daptomycin in all 75 isolates, and to fosfomycin in 21 of 22 isolates (96%). The outcome data was available for 66 patients (88%). The treatment success after 3 years was 83.7% (95% confidence interval [CI]; 76.1-96.7%) and the clinical success was 67.5% (95% CI; 57.3-80.8%). In 11 patients (17%), a new PJI episode caused by a different pathogen occurred. All failures occurred within 3 years after surgery.

Conclusion: About half of enterococcal PJI were polymicrobial infections. The treatment success was high (84%). All treatment failures occurred within the first 3 years after revision surgery. Interestingly, 17% of patients experienced a new PJI caused by another pathogen at a later stage.

Trial Registration: The study was retrospectively registered with the public clinical trial identification NCT0253022 at https://www.clinicaltrials.gov on 15 July 2015.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12879-019-4691-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6935141PMC
December 2019

Hip stress distribution - Predictor of dislocation in hip arthroplasties. A retrospective study of 149 arthroplasties.

PLoS One 2019 20;14(11):e0225459. Epub 2019 Nov 20.

Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia.

Dislocation after hip arthroplasty is still a major concern. Recent study of the volumetric wear of the cup has suggested that stresses studied in a one-legged stance model could predispose arthroplasty dislocation. The aim of this work was to study whether biomechanical parameters of contact stress distribution in total hip arthroplasty during a neutral hip position can predict a higher possibility of the arthroplasty dislocating. Biomechanical parameters were determined using 3-dimensional mathematical models of the one-legged stance within the HIPSTRESS method. Geometrical parameters were measured from standard anteroposterior X-ray images of the pelvis and proximal femora. Fifty-five patients subjected to total hip arthroplasty that later suffered dislocation of the head and, for comparison, ninety-four total hip arthroplasties that were functional at least 10 years after the implantation, were included in the study. Arthroplasties that suffered dislocation had on average a 6% higher resultant hip force than the control group (p = 0.004), 11% higher peak stress on the load-bearing area (p = 0.001) and a 50% more laterally positioned stress pole (p = 0.026), all parameters being less favorable in the group of unstable arthroplasties. There was no statistically significant difference in the gradient index or in the functional angle of the weight bearing. Our study showed that arthroplasties that show a tendency to push the head out of the cup in the representative body position-the one-legged stance-are prone to dislocation. An unfavorable resultant hip force, peak stress on the load bearing and laterally positioned stress pole are predictors of arthroplasty dislocation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0225459PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6867650PMC
March 2020

Timing of implant-removal in late acute periprosthetic joint infection: A multicenter observational study.

J Infect 2019 09 15;79(3):199-205. Epub 2019 Jul 15.

Infectious Diseases Section, Internal Medicine Service, Hospital Italiano de Buenos Aires, Argentina.

Objectives: We evaluated the treatment outcome in late acute (LA) periprosthetic joint infections (PJI) treated with debridement and implant retention (DAIR) versus implant removal.

Methods: In a large multicenter study, LA PJIs of the hip and knee were retrospectively evaluated. Failure was defined as: PJI related death, prosthesis removal or the need for suppressive antibiotic therapy. LA PJI was defined as acute symptoms <3 weeks in patients more than 3 months after the index surgery and with a history of normal joint function.

Results: 445 patients were included, comprising 340 cases treated with DAIR and 105 cases treated with implant removal (19% one-stage revision (n = 20), 74.3% two-stage revision (n = 78) and 6.7% definitive implant removal (n = 7). Overall failure in patients treated with DAIR was 45.0% (153/340) compared to 24.8% (26/105) for implant removal (p < 0.001). Difference in failure rate remained after 1:1 propensity-score matching. A preoperative CRIME80-score ≥3 (OR 2.9), PJI caused by S. aureus (OR 1.8) and implant retention (OR 3.1) were independent predictors for failure in the multivariate analysis.

Conclusion: DAIR is a viable surgical treatment for most patients with LA PJI, but implant removal should be considered in a subset of patients, especially in those with a CRIME80-score ≥3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jinf.2019.07.003DOI Listing
September 2019

Skeletal-muscle-derived mesenchymal stem/stromal cells from patients with osteoarthritis show superior biological properties compared to bone-derived cells.

Stem Cell Res 2019 07 14;38:101465. Epub 2019 May 14.

University of Ljubljana, Faculty of Pharmacy, Department of Clinical Biochemistry, Askerceva 7, Ljubljana 1000, Slovenia. Electronic address:

Mesenchymal stem/stromal cells (MSCs) are being exploited for patient-derived stem-cell therapies. As the biological properties of MSCs derived from skeletal muscle of osteoarthritis patients are poorly understood, the aim of this study was to compare muscle MSCs with well-recognized bone and bone marrow-derived MSCs from these patients. Paired samples of skeletal muscle and trabecular bone tissue were obtained from 21 patients with osteoarthritis. Isolated cells were compared using ex vivo immunophenotyping and detailed in vitro analyses. These included the colony forming unit fibroblast assay, growth kinetics, senescence, multilineage potential, immunophenotyping, and MSC marker gene expression profiling. Freshly isolated MSCs from muscle showed improved viability over bone-derived MSCs, with similar mesenchymal fraction. Muscle-derived MSCs showed superior clonogenicity, higher growth rates, and lower doubling times. Muscle-derived MSCs also showed superior osteogenic and myogenic properties and a positive correlation between CD271 expression and adipogenesis. Senescence rate as well as adipogenic and chondrogenic potentials were similar. Skeletal muscle-derived MSCs of osteoarthritis patients have superior clonogenicity and growth kinetics compared to bone-derived MSCs, making them a good candidate for autologous stem-cell therapies. Moreover, the positive correlation between CD271 and adipogenesis suggest that CD271 expressing muscle MSCs might contribute to muscle steatosis observed in osteoarthritis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scr.2019.101465DOI Listing
July 2019

Erysipelas or cellulitis with a prosthetic joint .

J Bone Jt Infect 2018 4;3(4):222-225. Epub 2018 Oct 4.

Department of Infectious Diseases, Hospital Universitario de Bellvitge, IDIBELL, Barcelona, Spain.

We describe a case of a 60-year old male who developed an acute prosthetic joint infection (PJI) of the knee, secondary to erysipelas of the lower leg due to beta-hemolytic Group G streptococci. As it is unknown how often this phenomenon occurs in patients with prosthetic implants and which patients are most prone to develop this complication, we analyzed: i) the incidence of the development of a PJI in these patients and ii) the clinical characteristics of streptococcal PJI during an episode of erysipelas/cellulitis. Based on a retrospective analysis of patients with a prosthetic implant presenting at the emergency department with erysipelas/cellulitis, 1 out of 10 patients developed a PJI. An additional analysis within a multicenter cohort on streptococcal PJI demonstrated in 22 patients that a secondary PJI due to erysipelas/cellulitis mostly develops in young implants (<5 years old). In 20 cases (91%), the skin infection was in the same limb as the joint prosthesis suggesting contiguous spread of bacteria. These data emphasizes the importance of preventive measures to reduce the occurrence of skin infections in patients with prosthetic implants, and if an erysipelas or cellulitis does occur, to monitor patients carefully.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7150/jbji.25519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6215988PMC
October 2018

Clinical outcome and risk factors for failure in late acute prosthetic joint infections treated with debridement and implant retention.

J Infect 2019 01 7;78(1):40-47. Epub 2018 Aug 7.

Infectious Diseases Section, Internal Medicine Service, Hospital Italiano de Buenos Aires, Argentina.

Objectives: Debridement, antibiotics and implant retention (DAIR) is the recommended treatment for all acute prosthetic joint infections (PJI), but its efficacy in patients with late acute (LA) PJI is not well described.

Methods: Patients diagnosed with LA PJI between 2005 and 2015 were retrospectively evaluated. LA PJI was defined as the development of acute symptoms (≤ 3 weeks) occurring ≥ 3 months after arthroplasty. Failure was defined as: (i) the need for implant removal, (ii) infection related death, (iii) the need for suppressive antibiotic therapy and/or (iv) relapse or reinfection during follow-up.

Results: 340 patients from 27 centers were included. The overall failure rate was 45.0% (153/340). Failure was dominated by Staphylococcus aureus PJI (54.7%, 76/139). Significant independent preoperative risk factors for failure according to the multivariate analysis were: fracture as indication for the prosthesis (odds ratio (OR) 5.4), rheumatoid arthritis (OR 5.1), age above 80 years (OR 2.6), male gender (OR 2.0) and C-reactive protein > 150 mg/L (OR 2.0). Exchanging the mobile components during DAIR was the strongest predictor for treatment success (OR 0.35).

Conclusion: LA PJIs have a high failure rate. Treatment strategies should be individualized according to patients' age, comorbidity, clinical presentation and microorganism causing the infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jinf.2018.07.014DOI Listing
January 2019

The Not-So-Good Prognosis of Streptococcal Periprosthetic Joint Infection Managed by Implant Retention: The Results of a Large Multicenter Study.

Clin Infect Dis 2017 Jun;64(12):1742-1752

Red Española de Investigación en Patología Infecciosa (REIPI).

Background.: Streptococci are not an infrequent cause of periprosthetic joint infection (PJI). Management by debridement, antibiotics, and implant retention (DAIR) is thought to produce a good prognosis, but little is known about the real likelihood of success.

Methods.: A retrospective, observational, multicenter, international study was performed during 2003-2012. Eligible patients had a streptococcal PJI that was managed with DAIR. The primary endpoint was failure, defined as death related to infection, relapse/persistence of infection, or the need for salvage therapy.

Results.: Overall, 462 cases were included (median age 72 years, 50% men). The most frequent species was Streptococcus agalactiae (34%), and 52% of all cases were hematogenous. Antibiotic treatment was primarily using β-lactams, and 37% of patients received rifampin. Outcomes were evaluable in 444 patients: failure occurred in 187 (42.1%; 95% confidence interval, 37.5%-46.7%) after a median of 62 days from debridement; patients without failure were followed up for a median of 802 days. Independent predictors (hazard ratios) of failure were rheumatoid arthritis (2.36), late post-surgical infection (2.20), and bacteremia (1.69). Independent predictors of success were exchange of removable components (0.60), early use of rifampin (0.98 per day of treatment within the first 30 days), and long treatments (≥21 days) with β-lactams, either as monotherapy (0.48) or in combination with rifampin (0.34).

Conclusions.: This is the largest series to our knowledge of streptococcal PJI managed by DAIR, showing a worse prognosis than previously reported. The beneficial effects of exchanging the removable components and of β-lactams are confirmed and maybe also a potential benefit from adding rifampin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/cid/cix227DOI Listing
June 2017

pH and metal concentration of synovial fluid of osteoarthritic joints and joints with metal replacements.

J Biomed Mater Res B Appl Biomater 2017 Nov 23;105(8):2507-2515. Epub 2016 Sep 23.

Valdoltra Orthopaedic Hospital, Jadranska c. 31, 6280, Ankaran, Slovenia.

Background: Due to degradation and metal dissolution during articulation of metal joint replacements the chemical periprosthetic environment may change. The aim was to establish whether metal replacements cause the local changes in pH and elevated metal concentrations.

Methods: pH was measured on samples from 167 patients: native hip and knee osteoarthritic joints, joints with hip and knee replacements revised for aseptic or septic reasons. pH of synovial fluid and periprosthetic tissue was measured perioperatively using a microelectrode and pH indicator papers for removed metal components. Metal concentrations were measured in 21 samples using inductively coupled plasma mass spectrometry.

Results: The mean pH value of synovial fluid at native osteoarthritic joints (n = 101) was 7.78 ± 0.38. The mean pH value of synovial fluid at revision aseptic operation (n = 58) was 7.60 ± 0.31, with statistically significant difference (p = 0.002) compared to native osteoarthritic joints. The mean pH value of synovial fluid at revision septic operation (n = 8) was 7.55 ± 0.25, with statistically significant difference (p = 0.038) compared to native osteoarthritic joints. Measurements in tissue and at stems were not reliable. In the majority of samples taken at revision increased levels of cobalt and chromium were measured.

Conclusion: A small but statistically significant difference was observed in the pH of synovial fluid between natural joints with degenerative diseases and joints treated with metal replacements. Based on the increased metal levels we expected the value of pH to be lower, but the influence of metal ions is counteracted by the buffering capacity of human body. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2507-2515, 2017.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jbm.b.33793DOI Listing
November 2017

Detection of bacteria with molecular methods in prosthetic joint infection: sonication fluid better than periprosthetic tissue.

Acta Orthop 2016 Aug 28;87(4):339-45. Epub 2016 Apr 28.

a Faculty of Health Sciences , University of Primorska , Izola ;

Background and purpose - The correct diagnosis of prosthetic joint infection (PJI) can be difficult because bacteria form a biofilm on the surface of the implant. The sensitivity of culture from sonication fluid is better than that from periprosthetic tissue, but no comparison studies using molecular methods on a large scale have been performed. We assessed whether periprosthetic tissue or sonication fluid should be used for molecular analysis. Patients and methods - Implant and tissue samples were retrieved from 87 patients who underwent revision operation of total knee or total hip arthroplasty. Both sample types were analyzed using broad-range (BR-) PCR targeting the 16S rRNA gene. The results were evaluated based on the definition of periprosthetic joint infection from the Workgroup of the Musculoskeletal Infection Society. Results - PJI was diagnosed in 29 patients, whereas aseptic failure was diagnosed in 58 patients. Analysis of sonication fluid using BR-PCR detected bacteria in 27 patients, whereas analysis of periprosthetic tissue by BR-PCR detected bacteria in 22 patients. In 6 of 7 patients in whom BR-PCR analysis of periprosthetic tissue was negative, low-virulence bacteria were present. The sensitivity and specificity values for periprosthetic tissue were 76% and 93%, respectively, and the sensitivity and specificity values for sonication fluid were 95% and 97%. Interpretation - Our results suggest that sonication fluid may be a more appropriate sample than periprosthetic tissue for BR-PCR analysis in patients with PJI. However, further investigation is required to improve detection of bacteria in patients with so-called aseptic failure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3109/17453674.2016.1165558DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4967274PMC
August 2016

Results of revision of total hip arthroplasty for alumina ceramic-on-ceramic bearing fracture.

Hip Int 2016 May 14;26(3):237-43. Epub 2016 Apr 14.

Valdoltra Orthopaedic Hospital, Ankaran - Slovenia.

Purpose: The purpose of this study was to compare the results of revision total hip arthroplasty after fracture of primary ceramic components using different type of revision bearing surfaces.

Methods: We analysed the results of 16 patients with a follow-up more than 3 years after first revision. 6 were revised to ceramic-on-ceramic (CoC) bearing, 9 to metal-on-polyethylene (MoP) and 1 to ceramic-on-cross-linked polyethylene (CoXLP) bearing.

Results: The mean follow-up was 87 months. Patients with revision to CoC had higher Harris Hip Score (HHS) of 89 points in comparison to the patients with revision to MoP with 84 points. Radiographic examinations revealed visible eccentric polyethylene wear with osteolysis in 3 out of 9 patients revised to MoP. There were no detrimental x-ray changes in patients revised to CoC components.

Conclusions: We consider CoC as the best option at revision operation for ceramic component fracture.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5301/hipint.5000340DOI Listing
May 2016

Does Preoperative Antimicrobial Prophylaxis Influence the Diagnostic Potential of Periprosthetic Tissues in Hip or Knee Infections?

Clin Orthop Relat Res 2016 Jan 8;474(1):258-64. Epub 2015 Aug 8.

Valdoltra Orthopaedic Hospital, Jadranska Cesta 31, 6280, Ankaran, Slovenia.

Background: Undiagnosed low-grade prosthetic joint infections (PJI) are recognized as an important reason for early failure of presumably aseptic revisions. Preoperatively administered antimicrobial prophylaxis reduces the incidence of PJI but it may reduce the sensitivity of microbiologic periprosthetic tissue cultures and consequently increase the incidence of undiagnosed septic prosthetic joint failures, which can lead to catastrophic serial revisions.

Questions/purposes: We wished to determine whether administration of preoperative antibiotics decreases the likelihood of diagnosing PJI in patients undergoing revision hip or knee arthroplasty in whom infection is suspected.

Methods: We prospectively enrolled and evaluated 40 patients (29 with THAs and 11 with TKAs) who met the following inclusion criteria: older than 18 years, with suspected PJI of unknown cause, undergoing surgical revision. After arthrotomy, three tissue samples were obtained for microbiologic analysis and diagnosis, and antimicrobial prophylaxis (cefazolin 2 g intravenously) then was administered. Later during the procedure, but before débridement and irrigation, the second set of three tissue samples was obtained from the same surgical area and was cultured. Tissue concentration of prophylactic antibiotic was verified with the second set of samples. A positive culture result was defined as one or more positive cultures (growth on agar at or before 14 days). We then compared the yield on the microbiologic cultures obtained before administration of antibiotics with the yield on the cultures obtained after antibiotics were administered. An a priori analysis was performed; with the numbers available, we had 98% power to detect a difference in diagnostic sensitivity of 33%.

Results: With the numbers available, we found no difference in the likelihood that an infection would be diagnosed between the samples obtained before and after administration of antimicrobial prophylaxis (odds ratio [OR] for positive microbial culture = 0.99; 95% CI, 0.40-2.48; p = 0.99). All measured tissue concentrations of cefazolin were greater than the minimum inhibitory concentration, therefore we found that antibiotic prophylaxis was adequate at the time of second-set tissue specimen recovery.

Conclusions: Results from this small, prospective series suggest that preoperative antimicrobial prophylaxis may be administered safely even in patients undergoing revision hip or knee arthroplasty in which microbiologic sampling is planned without compromising the diagnostic sensitivity of tissue sample cultures. However, before applying our results more generally, our findings need to be confirmed in larger, multicenter studies that would allow evaluation by sex, procedure, bacteriology, and other potentially important factors.

Level Of Evidence: Level I, diagnostic study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11999-015-4486-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4686528PMC
January 2016

Human beta-defensin-3 producing cells in septic implant loosening.

J Mater Sci Mater Med 2015 Feb 6;26(2):98. Epub 2015 Feb 6.

Department of Anatomy, Institute of Biomedicine, BMH 1, PO Box 63, 00014, Helsinki, Finland,

Human β-defensin-3 (hBD-3) has been found in synovial fluid and later in periprosthetic tissues in septic joint implant loosening. The aim of the present study was to identify its cellular sources. Tissue samples from 12 patients were analyzed. A fully automatic Leica BOND MAX staining robot was used. Affinity-purified rabbit anti-human hBD-3 IgG was applied in a two-layer horse radish peroxidase/anti-rabbit-labeled polymer method. Double immunofluorescence of hBD3 together with CD68, CD31, heat shock protein 47 (HSP47) and mast cell tryptase (MCT) staining was done. Human BD-3 was found in monocyte/macrophage-like cells, vascular endothelial cells and fibroblasts-like cells, but was weakly expressed in foreign body giant cells and negative in neutrophils. Human BD-3 was found in CD68 and CD31 immunoreactive cells, whereas HSP47 and MCT positive cells were hBD-3 negative. Immunostaining of hBD-3 was strong in some tissue areas but weak or absent in others. Monocyte/macrophages and endothelial cells were established in this study as the major cellular sources of hBD-3 in septic loosening, but fibroblasts and foreign body giant cells can also contribute to its production. The heterogeneous topological staining of hBD-3 suggests local regulation, possibly by bacterial products, damage-associated molecular patterns and cytokines. The results explain the increased synovial fluid/tissue concentrations of hBD-3 in septic loosening.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10856-015-5440-4DOI Listing
February 2015

Identification of the same species in at least two intra-operative samples for prosthetic joint infection diagnostics yields the best results with broad-range polymerase chain reaction.

Int Orthop 2015 May 19;39(5):975-9. Epub 2014 Oct 19.

Faculty of Health Sciences, University of Primorska, Polje 42, 6310, Izola, Slovenia,

Purpose: Prosthetic joint infection (PJI) is a devastating complication of total joint arthroplasty. No single laboratory test has perfect sensitivity and specificity; however, culture of periprosthetic tissue is the standard method for PJI diagnosis. Interpretation of positive culture results in PJI diagnostics can be difficult due to the possibility of contamination with microorganisms originating from skin micro flora. Criteria have been established to aid in distinguishing pathogen from contaminant for culture results. A similar criterion has not however been established for polymerase chain reaction (PCR) analysis, which is in part responsible for confusion about the reliability of PCR for PJI diagnostics. The aim of our study was to establish a criterion for interpretation of broad range (BR) PCR results in PJI diagnostics.

Methods: Samples of periprosthetic tissue were retrieved from 100 patients with joint prosthesis failure and analysed with BR-PCR. The results of BR-PCR were evaluated based on the number of samples of periprosthetic tissue with the same bacterial species.

Results: The sensitivity (87.5%) of BR-PCR was highest if the same species was present in at least one sample, although this criterion also resulted in the lowest specificity (92.1%). The sensitivity decreased (83.2%), although without a statistically significant difference, if the same species was present in two or more samples but, at the same time, specificity increased (100%), with a statistically significant difference.

Conclusions: For diagnostics of PJI with BR-PCR the criterion of the same bacterial species in at least two specimens of periprosthetic tissue from the same patient should be used for interpretation of positive results.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00264-014-2552-2DOI Listing
May 2015

Acute osteomyelitis in children.

N Engl J Med 2014 04;370(14):1364-5

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1056/NEJMc1402234DOI Listing
April 2014