First Results in the Search for Dark Sectors at NA64 with the CERN SPS High Energy Muon Beam.

We report the first search for dark sectors performed at the NA64 experiment employing a high energy muon beam and a missing energy-momentum technique. Muons from the M2 beamline at the CERN Super Proton Synchrotron with a momentum of 160 GeV/c are directed to an active target. The signal signature consists of a single scattered muon with momentum <80 GeV/c in the final state, accompanied by missing energy, i.e., no detectable activity in the downstream calorimeters. For a total dataset of (1.98±0.02)×10^{10} muons on target, no event is observed in the expected signal region. This allows us to set new limits on the remaining (m_{Z^{'}},g_{Z^{'}}) parameter space of a new Z^{'} (L_{µ}-L_{τ}) vector boson which could explain the muon (g-2)_{µ} anomaly. Additionally, our study excludes part of the parameter space suggested by the thermal dark matter relic abundance. Our results pave the way to explore dark sectors and light dark matter with muon beams in a unique and complementary way to other experiments.

Peri-Transplant Inflammation and Long-Term Diabetes Outcomes Were Not Impacted by Either Etanercept or Alpha-1-Antitrypsin Treatment in Islet Autotransplant Recipients.

The instant blood-mediated inflammatory response (IBMIR) causes islet loss and compromises diabetes outcomes after total pancreatectomy with islet autotransplant (TPIAT). We previously reported a possible benefit of etanercept in maintaining insulin secretion 3 months post-TPIAT. Here, we report 2-year diabetes outcomes and peri-operative inflammatory profiles from a randomized trial of etanercept and alpha-1 antitrypsin (A1AT) in TPIAT. We randomized 43 TPIAT recipients to A1AT (90 mg/kg IV x6 doses, n = 13), etanercept (50 mg then 25 mg SQ x 5 doses, n = 14), or standard care (n = 16). Inflammatory cytokines, serum A1AT and unmethylated insulin DNA were drawn multiple times in the perioperative period. Islet function was assessed 2 years after TPIAT with mixed meal tolerance test, intravenous glucose tolerance test and glucose-potentiated arginine induced insulin secretion. Cytokines, especially IL-6, IL-8, IL-10, and MCP-1, were elevated during and after TPIAT. However, only TNFα differed significantly between groups, with highest levels in the etanercept group (p = 0.027). A1AT increased after IAT in all groups (p < 0.001), suggesting endogenous upregulation. Unmethylated insulin DNA ratios (a marker of islet loss) and 2 years islet function testing were similar in the three groups. To conclude, we found no sustained benefit from administering etanercept or A1AT in the perioperative period.

Brivaracetam effectiveness and tolerability in older and younger adults with epilepsy: EXPERIENCE, a pooled analysis of international data from retrospective studies.

This analysis assessed the effectiveness and tolerability of brivaracetam (BRV) in older (≥65 years of age) and younger (≥16 to <65 years of age) adults with epilepsy. This was a subgroup analysis from EXPERIENCE/EPD332, a pooled analysis of individual patient records from multiple independent, non-interventional studies of patients with epilepsy starting BRV in Australia, Europe, and the United States. Included patients had ≥6 months of follow-up data. Outcomes included responders (≥50 % reduction from baseline in seizure frequency), seizure freedom (no seizures within 3 months before the time point), and continuous seizure freedom (no seizures from baseline) at 12 months; BRV discontinuation during the whole study follow-up; and treatment-emergent adverse events (TEAEs) at 3, 6, and 12 months. Patients with missing data after BRV discontinuation were deemed non-responders/not seizure-free. Analysis populations included the Full Analysis Set (FAS; patients who received ≥1 BRV dose and had seizure type and age documented at baseline) and the modified FAS (FAS patients who had ≥1 seizure recorded during baseline). The FAS was used for all outcomes except seizure reduction. The FAS included 147 (8.9 %) patients aged ≥65 years and 1497 (91.1 %) aged ≥16 to <65 years. Compared with the younger subgroup, patients aged ≥65 years had a longer median epilepsy duration (33.0 years [n = 144] vs 17.0 years [n = 1460]) and lower median seizure frequency at index (2.0 seizures/28 days [n = 129] vs 4.0 seizures/28 days [n = 1256]), and less commonly had >1 prior antiseizure medication (106/141 [75.2 %] vs 1265/1479 [85.5 %]). At 12 months, a numerically higher percentage of patients aged ≥65 years versus the younger subgroup achieved ≥50 % seizure reduction (46.5 % [n = 71] vs 36.0 % [n = 751]), seizure freedom (26.0 % [n = 100] vs 13.9 % [n = 1011]), and continuous seizure freedom (22.0 % [n = 100] vs 10.7 % [n = 1011]). During the whole study follow-up, 43/147 (29.3 %) patients aged ≥65 years and 508/1492 (34.0 %) aged ≥16 to <65 years discontinued BRV. The incidence of TEAEs since the prior visit was similar in both subgroups at 3 months (≥65 years vs ≥16 to <65 years: 38/138 [27.5 %] vs 356/1404 [25.4 %]), 6 months (19/119 [16.0 %] vs 176/1257 [14.0 %]), and 12 months (8/104 [7.7 %] vs 107/1128 [9.5 %]). This real-world analysis suggests BRV was effective in patients aged ≥65 years and ≥16 to <65 years, with numerically higher effectiveness in the older subgroup. BRV was well tolerated in both subgroups.

Technical note: preliminary surgical experience with a new implantable epicranial stimulation device for chronic focal cortex stimulation in drug-resistant epilepsy.

PURPOSE: This study is to report some preliminary surgical considerations and outcomes after the first implantations of a new and commercially available implantable epicranial stimulation device for focal epilepsy. METHODS: We retrospectively analyzed data from clinical notes. Outcome parameters were as follows: wound healing, surgery time, and adverse events. RESULTS: Five patients were included (17-52 y/o; 3 female). Epicranial systems were uneventfully implanted under neuronavigation guidance. Some minor adverse events occurred. Wound healing in primary intention was seen in all patients. Out of these surgeries, certain concepts were developed: Skin incisions had to be significantly larger than expected. S-shaped incisions appeared to be a good choice in typical locations behind the hairline. Preoperative discussions between neurologist and neurosurgeon are mandatory in order to allow for the optimal coverage of the epileptogenic zone with the electrode geometry. CONCLUSION: In this first small series, we were able to show safe implantation of this new epicranial stimulation device. The use of neuronavigation is strongly recommended. The procedure is simple but not trivial and ideally belongs in the hands of a neurosurgeon.

The Value of Preoperative Ultrasound-Determined Fluid Film and Joint Aspiration in Revision Hip Arthroplasty.

BACKGROUND: Data regarding the diagnostic value of ultrasound (US)-determined fluid film and joint aspiration prior to revision total hip arthroplasty for suspected periprosthetic joint infections (PJIs) are limited. This study aimed to analyze the value of US-determined fluid film, characterized the preoperative and intraoperative microbiological spectrum and resistance patterns, and compared the concordance between preoperative synovial fluid and intraoperative culture results. METHODS: We analyzed 366 US examinations from 324 patients prior to revision total hip arthroplasty. Selected cases were grouped into clearly infected, noninfected, and inconclusive cohorts, according to the International Consensus Meeting 2018 Criteria. For US-determined fluid film <1 mm, no aspiration was performed based on our institutional protocol. Patients were grouped into no aspiration (144 of 366; [39.3%]), dry tap (21 of 366; [5.7%]), and a successful tap (201 of 366; [54.9%]). The microbiological spectrum and antibiograms were compared between preoperative and intraoperative results. RESULTS: The absence of US-determined fluid film showed no correlation with the presence of a hip PJI. Overall, 31.9% cases of the no-aspiration group had a PJI. In total, 13.5% discrepancies were found between successful taps and intraoperative cultures. The most prevalent microorganisms in preoperative synovial fluid were Staphylococcus epidermidis and Staphylococcus aureus (20.8%), while intraoperatively S. epidermidis (26.3%) and Cutibacterium acnes (14.5%) were leading. Additional microorganisms were identified in 32.5% of intraoperative cultures. There were no differences between resistance patterns of preoperative and intraoperative concordant microorganisms. CONCLUSIONS: Absence of US-determined fluid film cannot rule out the presence of a hip PJI. Combined microbiological results from hip US aspirations and subsequent surgical procedures are crucial to design an effective treatment for suspected hip PJI.

Fully automated assessment of the knee alignment on long leg radiographs following corrective knee osteotomies in patients with valgus or varus deformities.

INTRODUCTION: The assessment of the knee alignment on long leg radiographs (LLR) postoperative to corrective knee osteotomies (CKOs) is highly dependent on the reader's expertise. Artificial Intelligence (AI) algorithms may help automate and standardise this process. The study aimed to analyse the reliability of an AI-algorithm for the evaluation of LLRs following CKOs. MATERIALS AND METHODS: In this study, we analysed a validation cohort of 110 postoperative LLRs from 102 patients. All patients underwent CKO, including distal femoral (DFO), high tibial (HTO) and bilevel osteotomies. The agreement between manual measurements and the AI-algorithm was assessed for the mechanical axis deviation (MAD), hip knee ankle angle (HKA), anatomical-mechanical-axis-angle (AMA), joint line convergence angle (JLCA), mechanical lateral proximal femur angle (mLPFA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibia angle (mMPTA) and mechanical lateral distal tibia angle (mLDTA), using the intra-class-correlation (ICC) coefficient between the readers, each reader and the AI and the mean of the manual reads and the AI-algorithm and Bland-Altman Plots between the manual reads and the AI software for the MAD, HKA, mLDFA and mMPTA. RESULTS: In the validation cohort, the AI software showed excellent agreement with the manual reads (ICC: 0.81-0.99). The agreement between the readers (Inter-rater) showed excellent correlations (ICC: 0.95-0. The mean difference in the DFO group for the MAD, HKA, mLDFA and mMPTA were 0.50 mm, - 0.12°, 0.55° and 0.15°. In the HTO group the mean difference for the MAD, HKA, mLDFA and mMPTA were 0.36 mm, - 0.17°, 0.57° and 0.08°, respectively. Reliable outputs were generated in 95.4% of the validation cohort. CONCLUSION:  he application of AI-algorithms for the assessment of lower limb alignment on LLRs following CKOs shows reliable and accurate results. LEVEL OF EVIDENCE: Diagnostic Level III.

Factors associated with favourable 5 year outcomes in islet transplant alone recipients with type 1 diabetes complicated by severe hypoglycaemia in the Collaborative Islet Transplant Registry.

AIMS/HYPOTHESIS: Islet transplantation has been studied in small cohorts of recipients with type 1 diabetes complicated by severe hypoglycaemic events (SHEs). We determined factors associated with favourable outcomes in a large cohort of recipients reported to the Collaborative Islet Transplant Registry (CITR). METHODS: In 398 non-uraemic islet transplant alone (ITA) recipients with type 1 diabetes and SHEs, transplanted between 1999 and 2015 and with at least 1 year follow-up, we analysed specified favourable outcomes against each of all available characteristics of pancreas donors, islet grafts, recipients and immunosuppressive regimens, as well as immunosuppression and procedure-related serious adverse events (SAEs). RESULTS: Four factors were associated with the highest rates of favourable outcomes: recipient age ≥35 years; total infused islets ≥325,000 islet equivalents; induction immunosuppression with T cell depletion and/or TNF-α inhibition; and maintenance with both mechanistic target of rapamycin (mTOR) and calcineurin inhibitors. At 5 years after the last islet infusion, of the recipients meeting these four common favourable factors (4CFF; N=126), 95% were free of SHEs, 76% had HbA1c <53 mmol/mol (7.0%), 73% had HbA1c <53 mmol/mol (7.0%) and absence of SHEs, and 53% were insulin independent, significantly higher rates than in the remaining recipients (<4CFF; N=272). The incidence of procedural and immunosuppression-related SAEs per recipient that resulted in sequelae, disability or death was low in both the 4CFF (0.056 per person) and <4CFF (0.074 per person) groups. CONCLUSIONS/INTERPRETATION: In recipients with type 1 diabetes complicated by SHEs, islet transplantation meeting 4CFF protected 95% from SHEs at 5 years after the last islet infusion and exerted a large and significant benefit on glycaemic control, with an acceptable safety profile for this subgroup of type 1 diabetes.

Incidence and Resolution of Eribulin-Induced Peripheral Neuropathy (IRENE) in Locally Advanced or Metastatic Breast Cancer: Prospective Cohort Study.

BACKGROUND: Eribulin, a halichondrin-class microtubule dynamics inhibitor, is a preferred treatment option for patients with advanced breast cancer who have been pretreated with an anthracycline and a taxane. Peripheral neuropathy (PN) is a common side effect of chemotherapies for breast cancer and other tumors. The Incidence and Resolution of Eribulin-Induced Peripheral Neuropathy (IRENE) noninterventional postauthorization safety study assessed the incidence and severity of PN in patients with breast cancer treated with eribulin. PATIENTS AND METHODS: IRENE is an ongoing observational, single-arm, prospective, multicenter, cohort study. Adult patients (≥18 years of age) with locally advanced or metastatic breast cancer and disease progression after 1-2 prior chemotherapeutic regimen(s) for advanced disease were treated with eribulin. Patients with eribulin-induced PN (new-onset PN or worsening of preexisting PN) were monitored until death or resolution of PN. Primary endpoints included the incidence, severity, and time to resolution of eribulin-induced PN. Secondary endpoints included time to disease progression and safety. RESULTS: In this interim analysis (data cutoff date: July 1, 2019), 67 (32.4%) patients experienced any grade eribulin-induced PN, and 12 (5.8%) patients experienced grade ≥3 eribulin-induced PN. Median time to resolution of eribulin-induced PN was not reached. Median time to disease progression was 4.6 months (95% CI, 4.0-6.5). Treatment-emergent adverse events (TEAEs) occurred in 195 (93.8%) patients and serious TEAEs occurred in 107 (51.4%) patients. CONCLUSION: The rates of any grade and grade ≥3 eribulin-induced PN observed in this real-world study were consistent with those observed in phase III randomized clinical trials. No new safety findings were observed.

Early on-treatment C-reactive protein and its kinetics predict survival and response in recurrent and/or metastatic head and neck cancer patients receiving first-line pembrolizumab.

PURPOSE: First-line immune checkpoint blockade has improved the prognosis of recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC), but response rates remain low. In this study, we aimed to investigate the prognostic value of CRP and its early kinetics to predict response and survival in R/M HNSCC. METHODS: A total of 87 patients who received first-line pembrolizumab for R/M HNSCC were analyzed. Three-fold cross-validation was used to estimate cut-off points of CRP at baseline and on-treatment (day 40 ± 10). Treatment response and survival were analyzed according to early CRP kinetics. The neutrophil-to-lymphocyte ratio (NLR) was used as a benchmark for the prognostic performance of CRP. RESULTS: On-treatment CRP below 2 mg/dl, 4x the upper limit of normal (ULN), was associated with increased overall survival (OS), while on-treatment CRP below 3 mg/dl (6x ULN) was correlated with a higher disease control rate (DCR) and increased progression-free survival (PFS). CRP flare-responders and CRP responders showed a higher DCR and longer PFS than CRP non-responders. An NLR above 6 was a negative prognosticator for progression. In multivariable analysis, on-treatment CRP prevailed as the only significant prognosticator for OS (HR: 4.97, CI95%: 2.18-11.32, p < 0.001) and PFS (HR: 2.07, CI95%: 1.07-3.99, p = 0.030). CONCLUSION: On-treatment CRP was identified as a prognostic biomarker for objective response and survival in R/M HNSCC patients receiving first-line pembrolizumab and could be easily incorporated into clinical practice as a widely available and cost-effective biomarker.

The ATR inhibitor berzosertib acts as a radio- and chemosensitizer in head and neck squamous cell carcinoma cell lines.

Alterations in the DNA damage response play a crucial role in radio- and chemoresistance of neoplastic cells. Activation of the Ataxia telangiectasia and Rad3-related (ATR) pathway is an important DNA damage response mechanism in head and neck squamous cell carcinoma (HNSCC). Berzosertib, a selective ATR inhibitor, shows promising radio- and chemosensitizing effects in preclinical studies and is well tolerated in clinical studies. The aim of this study was to elucidate the effect of berzosertib treatment in combination with radiation and cisplatin in HNSCC. The HNSCC cell lines Cal-27 and FaDu were treated with berzosertib alone and in combination with radiation or cisplatin. Cell viability and clonogenic survival were evaluated. The effect of combination treatment was evaluated with the SynergyFinder or combination index. Apoptosis was assessed via measurement of caspase 3/7 activation and migration was evaluated using a wound healing assay. Berzosertib treatment decreased cell viability in a dose-dependent manner and increased apoptosis. The IC50 of berzosertib treatment after 72 h was 0.25-0.29 µM. Combination with irradiation treatment led to a synergistic increase in radiosensitivity and a synergistic or additive decrease in colony formation. The combination of berzosertib and cisplatin decreased cell viability in a synergistic manner. Additionally, berzosertib inhibited migration at high doses. Berzosertib displays a cytotoxic effect in HNSCC at clinically relevant doses. Further evaluation of combination treatment with irradiation and cisplatin is strongly recommended in HNSCC patients as it may hold the potential to overcome treatment resistance, reduce treatment doses and thus mitigate adverse events.

Search for Light Dark Matter with NA64 at CERN.

Thermal dark matter models with particle χ masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV χ production through the interaction mediated by a new vector boson, called the dark photon A^{'}, in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With 9.37×10^{11} electrons on target collected during 2016-2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the A^{'} couplings to photons for masses m_{A^{'}}≲0.35 GeV, and to exclude scalar and Majorana dark matter with the χ-A^{'} coupling α_{D}≤0.1 for masses 0.001≲m_{χ}≲0.1 GeV and 3m_{χ}≤m_{A^{'}}.

A randomized controlled pilot trial of etanercept and alpha-1 antitrypsin to improve autologous islet engraftment.

BACKGROUND: In total pancreatectomy with islet auto-transplantation, successful diabetes outcomes are limited by islet loss from the instant blood mediated inflammatory response. We hypothesized that blockade of the inflammatory response with either etanercept or alpha-1-antitrypsin would improve islet function and insulin independence. METHODS: We randomized 43 participants to receive A1AT (90 mg/kg x 6 doses, n = 13), or etanercept (50 mg then 25 mg x 5 doses, n = 14), or standard care (n = 16), aiming to reduce detrimental effects of innate inflammation on early islet survival. Islet graft function was assessed using mixed meal tolerance testing, intravenous glucose tolerance testing, glucose-potentiated arginine-induced insulin secretion studies, HbA1c, and insulin dose 3 months and 1 year post-TPIAT. RESULTS: We observed the most robust acute insulin response (AIRglu) and acute C-peptide response to glucose (ACRglu) at 3 months after TPIAT in the etanercept-treated group (p ≤ 0.02), but no differences in other efficacy measures. The groups did not differ overall at 1 year but when adjusted by sex, there was a trend towards a sex-specific treatment effect in females (AIRglu p = 0.05, ACRglu p = 0.06), with insulin secretion measures highest in A1AT-treated females. CONCLUSION: Our randomized trial supports a potential role for etanercept in optimizing early islet engraftment but it is unclear whether this benefit is sustained. Further studies are needed to evaluate possible sex-specific responses to either treatment. CLINICAL TRIAL NOTATION: This study was performed under an Investigational New Drug Application (IND #119828) from the Food and Drug Administration and was registered on clinicaltrials.gov (NCT#02713997).

Failure to use new breakthrough treatments for epilepsy.

Despite the approval of ~20 additional antiseizure medications (ASMs) since the 1980s, one-third of epilepsy patients experience seizures despite therapy. Drug-resistant epilepsy (DRE) is associated with cognitive and psychiatric comorbidities, socioeconomic impairment, injuries, and a 9.3-13.4 times higher mortality rate than in seizure-free patients. Improved seizure control can reduce morbidity and mortality. Two new ASMs were launched in the United States in 2020: cenobamate for focal epilepsy in adults and fenfluramine for Dravet syndrome (DS). They offer markedly improved efficacy. Cenobamate achieved 21% seizure freedom with the highest dose and decreased tonic-clonic seizures by 93% during maintenance treatment in a randomized clinical trial (RCT). In long-term, open-label studies, 10%-36% of patients were seizure-free for a median duration of ~30-45 months. Fenfluramine treatment in DS reduced convulsive seizure frequency by 56% over placebo at the highest dose, with 8% of patients free of convulsive seizures, and 25% with only one convulsive seizure over 14 weeks. These results were sustained for up to 3 years in open-label extension studies. Mortality was reduced 5-fold. These results are superior to all other approved ASMs, placing these two drugs among the most effective antiseizure therapies. The adverse event profiles resemble those of other ASMs. Despite greater efficacy and similar toxicity, these medications are infrequently used. Two years after US market entry, < 5% of either adults with focal DRE or patients with DS were treated with either cenobamate or fenfluramine. We believe this is a failure of our medical system, resulting from limited knowledge about these drugs stemming partly from the separation of academia from industry; restrictions to access created by health care payors, hospitals, and regulatory agencies; and insufficient post-launch information about the efficacy and safety of these ASMs.

Targeting TGF beta receptor 1 in head and neck squamous cell carcinoma.

OBJECTIVES: The transforming growth factor-Beta (TGF-ß) pathway may be involved in the radioresistance of head and neck squamous cell carcinoma (HNSCC). This study analyzed TGF-ß receptor 1 (TGFBR1) expression in HNSCC patients and evaluated the antineoplastic and radiosensitizing effects of vactosertib, a novel TGFBR1 inhibitor, in vitro. MATERIALS AND METHODS: TGFBR1 expression was examined in HNSCC patients at the mRNA level in silico and the protein level by immunohistochemistry, including surgical specimens of primary tumors, matched lymph node metastasis, and recurrent disease. Furthermore, a novel small molecule TGFBR1 inhibitor was evaluated in HNSCC cell lines. Finally, an indirect coculture model using patient-derived cancer-associated fibroblasts was applied to mimic the tumor microenvironment. RESULTS: Patients with high TGFBR1 mRNA levels showed significantly worse overall survival in silico (OS, p = 0.024). At the protein level, an association between TGFBR1+ tumor and OS was observed for the subgroup with TGFBR1-stroma (p = 0.001). Those results prevailed in multivariable analysis. Inhibition of TGFBR1 showed antineoplastic effects in vitro. In combination with radiation, vactosertib showed synergistic effects. CONCLUSION: Our results indicate a high risk of death in tumorTGFBR1+ |stromaTGFBR1- expressing patients. In vitro data suggest a potential radiosensitizing effect of TGFBR1 inhibition by vactosertib.

Adult T-cells impair neonatal cardiac regeneration.

AIMS: Newborn mice and humans display transient cardiac regenerative potential that rapidly declines postnatally. Patients who survive a myocardial infarction (MI) often develop chronic heart failure due to the heart's poor regeneration capacity. We hypothesized that the cardiac 'regenerative-to-scarring' transition might be driven by the perinatal shifts observed in the circulating T-cell compartment. METHODS AND RESULTS: Post-MI immune responses were characterized in 1- (P1) vs. 7-day-old (P7) mice subjected to left anterior descending artery ligation. Myocardial infarction induced robust early inflammatory responses (36 h post-MI) in both age groups, but neonatal hearts exhibited rapid resolution of inflammation and full functional recovery. The perinatal loss of myocardial regenerative capacity was paralleled by a baseline increase in αß-T cell (CD4+ and CD8+) numbers. Strikingly, P1-infarcted mice reconstituted with adult T-cells shifted to an adult-like healing phenotype, marked by irreversible cardiac functional impairment and increased fibrosis. Infarcted neonatal mice harbouring adult T-cells also had more monocyte-derived macrophage recruitment, as typically seen in adults. At the transcriptome level, infarcted P1 hearts that received isolated adult T-cells showed enriched gene sets linked to fibrosis, inflammation, and interferon-gamma (IFN-γ) signalling. In contrast, newborn mice that received isolated Ifng-/- adult T-cells prior to MI displayed a regenerative phenotype that resembled that of its age-matched untreated controls. CONCLUSION: Physiological T-cell development or adoptive transfer of adult IFN-γ-producing T-cells into neonates contributed to impaired cardiac regeneration and promoted irreversible structural and functional cardiac damage. These findings reveal a trade-off between myocardial regenerative potential and the development of T-cell competence.

Alpha-defensin as a diagnostic tool in revision total knee arthroplasties with unexpected positive intraoperative cultures and unexpected culture negative intraoperative cultures.

PURPOSE: Unexpected-positive-intraoperative-cultures (UPIC) are common in presumed aseptic revision-total-knee-arthroplasties (rTKA). However, the clinical significance is not entirely clear. In contrast, in some presumably septic rTKA, identification of an underlying pathogen was not possible, so-called unexpected-negative-intraoperative-cultures (UNIC). The purpose of this study was to evaluate the potential use of synovial alpha-defensin (AD) levels in these patients. METHODS: Synovial AD levels from 143 rTKAs were evaluated retrospectively from our prospectively maintained institutional periprostetic joint infection (PJI) biobank and database. The 2018-International Consensus Meeting (ICM) criteria was used to define the study groups. Samples from UPICs with a minimum of one positive intraoperative culture (ICM 2- ≥ 6) (n = 20) and UNIC's (ICM ≥ 6) (n = 14) were compared to 34 septic culture-positive samples (ICM ≥ 6) and 75 aseptic culture-negative (ICM 0-1). Moreover, AD-lateral-flow-assay (ADLF) and an enzyme-linked-immunosorbent-assay (ELISA) in detecting the presence of AD in native and centrifuged synovial fluid specimens was performed. Concentration of AD determined by ELISA and ADLF methods, as well as microbiological, and histopathological results, serum and synovial parameters along with demographic factors were analysed. RESULTS: AD was positive in 31/34 (91.2%) samples from the septic culture-positive group and in 14/14 (100%) samples in the UNIC group. All UPIC samples showed a negative AD result. Positive AD samples were highly associated with culture positive and histopathological results (p < 0.001). No high-virulent microorganisms (0/20) were present in the UPIC group, compared to infected-group (19/34; 55.9%). High virulent microorganisms showed a positive AD result in 89.5% (17/19) of the cases. Methicillin resistant Staphylococcus epidermis (MRSE) infections had significantly higher AD levels than with methicillin susceptible S. epidermdis (MSSE) (p = 0.003). ELISA and ADLF tests were positive with centrifuged (8/8) and native (8/8) synovial fluid. CONCLUSION: AD showed a solid diagnostic performance in infected and non-infected revisions, and it provided an additional value in the diagnosis of UPIC and UNIC associated to rTKAs. Pathogen virulence as well as antibiotic resistance pattern may have an effect on AD levels. Centrifugation of synovial fluid had no influence on ADLF results.

Clinical impact of microbiological results in two-stage revision arthroplasty with spacer exchange.

INTRODUCTION: Patients who require a spacer exchange as part of a two-stage procedure for the treatment of periprosthetic hip and knee joint infections (PJI) have high failure rates. Little is known about the clinical impact of microbiological results and changes in the microbiological spectrum and resistance pattern in these patients. MATERIAL AND METHODS: Between 01/2011 and 12/2019, 312 patients underwent a total of 327 two-stage revision arthroplasties at our institution. A spacer exchange was required in 52/312 (16.7%) patients (27 knee/25 hip). Microbiological results, antibiotic resistance patterns, patient's host factors as well as re-revision and re-infection rates at a median follow-up of 47.8 months (range 12.2-116.7 months) were analyzed. A propensity score (PS)-matched analysis of patients who underwent spacer exchange and patients treated with standard two-stage procedure was performed. RESULTS: We found a high number of microbiological spectrum changes in patients with multiple culture positive procedures between explantations and spacer exchanges (10/12 [83.3%]), spacer exchanges and reimplantations (3/4 [75%]) as well as between reimplantations and subsequent re-revision surgeries (5/6 [83.3%]). In 9/52 (17.3%) patients, same microorganisms were detected repeatedly in two different procedures. We observed changes in the antibiotic resistance patterns in 6/9 (66.7%) of these patients. High re-infection rates were found in patients with culture positive reimplantations (10/12 [83.3%]), and low re-infection rates were found in patients with culture negative reimplantations (2/40 [5%]; p < 0.001). Between patients with and without spacer exchange, no differences were found in the re-revision rates (13/52 [25%] with vs. 13/52 [25%] without; p = 1.00) as well as re-infection rates (12/52 [23.1%] with vs. 8/52 [15.4%] without; p = 0.32). CONCLUSIONS: Changes in microbiological spectrum and antibiotic resistance patterns between stages are common in patients who require a spacer exchange. If eradication of the microorganism at reimplantation can be accomplished, comparable re-revision rates to standard two-stage procedures can be achieved.

Changes in microbiological spectrum and antibiotic susceptibility in two-stage exchange for periprosthetic shoulder infections.

BACKGROUND: Periprosthetic joint infections (PJI) are a major concern in shoulder arthroplasty, which in some cases require two-stage exchange. While it was shown that low-virulence bacteria are the most isolated pathogens in shoulder PJI, little is known about changes in microbiological spectrum and resistance patterns during two-stage revision. METHODS: This retrospective study included all patients (n = 25) who received a two-stage revision from January 2011 to December 2020 for shoulder PJI in one institution. Microbiological spectrum, antimicrobial resistance patterns, and re-revision rates of culture positive first- and second-stage procedures were analyzed. The mean follow-up time was 29.7 months (range 8; 115 months). At final follow-up, subjective shoulder value (SSV) and visual analog scale (VAS) score for pain and satisfaction with the surgery were assessed. RESULTS: In 25 patients, a total of 54 2-stage exchange procedures were performed and positive cultures were obtained in 36 of these surgeries (66.7%). A total of 7 out of 25 patients (28.0%) showed a positive microbiological culture at first and second stages. In those patients, the mean time between first and second stages was 30.9 weeks (range 6; 70). Three out of those seven patients (42.9%) had a polymicrobial spectrum with one microorganism persistent at stage two, including Cutibacterium acnes (n = 1) and Staphylococcus epidermidis (MRSE) (n = 2). In all these cases, antimicrobial resistance patterns changed. All cultures with monomicrobial spectrum (n = 4) at first stage showed a changed spectrum. Patients with positive first- and second-stage revisions showed a mean SSV of 49.3% ± 23.5 versus 52.9% ± 29.5 in single positive patients (p = 0.76). Re-revision was performed in five cases, two of those in patients with positive first- and second-stage cultures. CONCLUSION: There is a high rate of changes in microbiological spectrum and resistance patterns between culture positive first- and second-stage procedures as well as subsequent re-revisions. Intraoperative samples during reimplantation should be taken and resistance reconsidered in case of re-revision.

Chondrosarcoma of the spine-a case report.

CASE: A 73-year-old male patient presented with a 3-month history of back pain. In bone scintigraphy and the FDG PET-CT scan (fluorodeoxyglucose positron-emission computed tomography), highly suspect uptake levels were found in TH12-L1. Accordingly, an osteodestructive process was found on MRI (magnetic resonance imaging). Following a successfully performed biopsy of TH12, histologic analysis of the bone material revealed a chondrosarcoma (G1; T4N2M0). Complete resection of the tumor was successfully performed, since chondrosarcoma are resistant to radiation and chemotherapy. CONCLUSION: As chondrosarcoma is a rare bone neoplasm, it must be considered in the differential diagnosis of lower back pain to initiate adequate treatment.

Intra-individual comparison of 18F-sodium fluoride PET-CT and 99mTc bone scintigraphy with SPECT in patients with prostate cancer or breast cancer at high risk for skeletal metastases (MITNEC-A1): a multicentre, phase 3 trial.

BACKGROUND: Detection of skeletal metastases in patients with prostate cancer or breast cancer remains a major clinical challenge. We aimed to compare the diagnostic performance of 99mTc-methylene diphosphonate (99mTc-MDP) single-photon emission CT (SPECT) and 18F-sodium fluoride (18F-NaF) PET-CT for the detection of osseous metastases in patients with high-risk prostate or breast cancer. METHODS: MITNEC-A1 was a prospective, multicentre, single-cohort, phase 3 trial conducted in ten hospitals across Canada. Patients aged 18 years or older with breast or prostate cancer with a WHO performance status of 0-2 and with high risk or clinical suspicion for bone metastasis, but without previously documented bone involvement, were eligible. 18F-NaF PET-CT and 99mTc-MDP SPECT were done within 14 days of each other for each participant. Two independent reviewers interpreted each modality without knowledge of other imaging findings. The primary endpoint was the overall accuracy of 99mTc-MDP SPECT and 18F-NaF PET-CT scans for the detection of bone metastases in the per-protocol population. A combination of histopathological, clinical, and imaging follow-up for up to 24 months was used as the reference standard to assess the imaging results. Safety was assessed in all enrolled participants. This study is registered with ClinicalTrials.gov, NCT01930812, and is complete. FINDINGS: Between July 11, 2014, and March 3, 2017, 290 patients were screened, 288 of whom were enrolled (64 participants with breast cancer and 224 with prostate cancer). 261 participants underwent both 18F-NaF PET-CT and 99mTc-MDP SPECT and completed the required follow-up for statistical analysis. Median follow-up was 735 days (IQR 727-750). Based on the reference methods used, 109 (42%) of 261 patients had bone metastases. In the patient-based analysis, 18F-NaF PET-CT was more accurate than 99mTc-MDP SPECT (84·3% [95% CI 79·9-88·7] vs 77·4% [72·3-82·5], difference 6·9% [95% CI 1·3-12·5]; p=0·016). No adverse events were reported for the 288 patients recruited. INTERPRETATION: 18F-NaF has the potential to displace 99mTc-MDP as the bone imaging radiopharmaceutical of choice in patients with high-risk prostate or breast cancer. FUNDING: Canadian Institutes of Health Research.