Minimally invasive lateral plating for diaphyseal fractures with extension into the proximal humerus and its implications for the deltoid muscle and its distal insertion: functional analysis and MR-imaging

BACKGROUND

In minimally invasive lateral plate osteosynthesis of the humerus (MILPOH) the plate is introduced through a deltoid split proximally and advanced through the central portion of the deltoid insertion and between bone and brachial muscle to the distal aspect of the humerus. The fracture is then indirectly reduced and bridged by the plate. Whereas it has been shown that the strong anterior and posterior parts of the distal deltoid insertion remain intact with this maneuver, its impact on deltoid muscle strength and muscular morphology remains unclear. It was the aim of this study to evaluate deltoid muscle function and MR-morphology of the deltoid muscle and its distal insertion after MILPOH.

METHODS

Six patients (median age 63 years, range 52-69 years, f/m 5/1) who had undergone MILPOH for diaphyseal humeral fractures extending into the proximal metaphysis and head (AO 12B/C(i)) between 08/2017 and 08/2020 were included. Functional testing was performed for the injured and uninjured extremity including strength measurements for 30/60/90° shoulder abduction and flexion at least one year postoperatively. Constant-Murley-Score (CMS) including an age-and gender-adjusted version, were obtained and compared to the uninjured side. Oxford Shoulder Score (OSS) and the Disability of the Arm, Shoulder and Hand (DASH) questionnaire were acquired for the affected extremity. Quality of life was measured using the EQ visual analogue scale (EQ-5D-5 L VAS). MR imaging was performed for both shoulders accordingly at the time of follow-up to assess the integrity of the distal insertion, muscle mass and fatty degeneration of the deltoid muscle. Muscle mass was determined by measuring the area of the deltoid muscle on the axial MR image at the height of the center of the humeral head.

RESULTS

Median follow-up was 29 months (range 12-48 months). Median difference of abduction strength after MILPOH was + 13% for 30°, 0% for 60° and - 22% for 90°. For flexion, the difference to the uninjured side was measured 5% for 30°, -7% for 60° and - 12% for 90°. Median CMS was 75 (66-82) for the operated extremity compared to 82 (77-90) for the uninjured side. Age- and gender-adapted CMS was calculated 88 (79-99) vs. 96 (89-107). Median OSS was 47 (40-48). DASH was 26 (15-36). EQ-5D-5 L VAS ranged from 81 to 95 with a median of 90. The median difference of the deltoid muscle area on MRI was 2% (-21% to + 53%) compared to the uninjured side. No fatty degeneration of the deltoid muscle was observed. The weaker central part of the distal deltoid insertion was exclusively perforated by the plate, leaving the strong anterior and posterior parts of the insertion intact in all patients.

CONCLUSIONS

MILPOH was associated with good functional and subjective outcome. Minor impairment of abduction strength was observed with increasing abduction angles. The reason for this impairment is unclear since MILPOH did not affect the structural quality of the deltoid muscle and the integrity of the strong anterior and posterior parts of its insertion remained intact.

TRIAL REGISTRATION

26/05/2023: ISRCTN51786146.

Measurement of polarization observables T, P, and H in π0 and η photoproduction off quasi-free nucleons

The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π 0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γ p → π 0 p and γ p → η p reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the η n system at W = 1.68 GeV . A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S 11 ( 1535 ) and S 11 ( 1650 ) resonances within the S 11 -partial wave.

In infertile women with subclinical hypothyroidism, with or without thyroid peroxidase antibodies, serum TSH during pregnancy follows preconception values and thyroid hormones remain stable

STUDY QUESTION

How does subclinical hypothyroidism, defined in infertile women during preconception by thyroid-stimulating hormone (TSH) >2.5 or >4.5 mIU/l, with or without thyroid peroxidase antibodies (anti-TPO) >100 IU/ml, impact thyroid hormone levels during pregnancy and after birth?

SUMMARY ANSWER

During pregnancy, TSH levels remain similar to those in preconception, even with supplementary thyroxine, whereas the serum levels of anti-TPO progressively decline.

WHAT IS KNOWN ALREADY

Overt hypothyroidism impacts both pregnancy and offspring but randomized clinical trials and cohort studies failed to detect the benefit of treatment with thyroxine in cases with low-threshold TSH or with anti-TPO during pregnancy.

STUDY DESIGN SIZE DURATION

First, the prevalence and reproducibility of two candidate cut-off levels of subclinical hypothyroidism in a cohort of 177 infertile women was compared with 171 women not aiming for pregnancy. Second, the impact of distinct setpoints of TSH in preconception (with or without anti-TPO) was monitored during pregnancy in 87 previously infertile women by high-frequency monitoring of thyroid function. Both studies were carried out from 2007 to 2019.

PARTICIPANTS/MATERIALS SETTING METHODS

Reproducibility and prevalence of subclinical hypothyroidism were examined in infertile women presenting in the fertility care unit of an academic institution. Women not aiming for pregnancy participated as controls. In both groups, TSH and anti-TPO were measured two times on different occasions. In addition, a group of previously infertile women with known preconception setpoints of TSH (with or without anti-TPO) were followed up prospectively throughout pregnancy and after birth. During pregnancy, serum was sampled weekly until Week 12, then monthly until delivery, and once after birth. Only cases with preconception TSH >4.5 mIU/l were supplemented with thyroxine. After collection of all samples, the serum levels of anti-TPO and the major thyroid hormones were measured. Prolactin with known fluctuations during pregnancy was used as reference.

MAIN RESULTS AND THE ROLE OF CHANCE

Measures of both TSH and anti-TPO at two different time points were accurate and reproducible. The odds of subclinical hypothyroidism in infertile women and controls were similar. During pregnancy, TSH closely followed preconception TSH levels, whereas serum levels of the thyroid hormones predominantly remained within or above (not below) the reference. Treatment of infertile women with preconception TSH >4.5 mIU/l with thyroxine resulted in higher free thyroxine (fT4) serum levels. The serum levels of anti-TPO declined as pregnancies evolved.

LIMITATIONS REASONS FOR CAUTION

The numbers of participants both in the prevalence study and in pregnancy did not reach the a priori estimated numbers. For ethical reasons, the patients with preconception TSH >4.5 mIU/l were treated with thyroxine. The findings apply to infertile women only.

WIDER IMPLICATIONS OF THE FINDINGS

We propose to use >4.5 mIU/l as the serum TSH threshold for supplementing women with thyroxine before pregnancy. During pregnancy, fT4 may be the better marker to monitor thyroid function. The consistent decrease of anti-TPO antibody levels during ongoing pregnancies must be considered a protective element.

STUDY FUNDING/COMPETING INTERESTS

The prevalence part of this study was supported by Merck-Serono, Geneva (TH006/EMR200007-603). The hormone measurements of the serum samples collected during the follow-up pregnancies were made possible by financial support of Roche Diagnostica (November 1721, 2017, Rotkreuz, Switzerland). I.D.G. was supported by a grant of the Repronatal Foundation, Basel, Switzerland. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

Research Database of UniBasel, project no. 576691 (2007).

Feasibility and image quality of myocardial perfusion imaging by CMR in patients with conditional and non-conditional cardiac devices

Purpose

First, to determine image quality using different cardiovascular magnetic resonance (CMR) perfusion protocols in patients with all available active device types in a real-world setting, including non-conditional devices.

Second, to demonstrate feasibility of high-quality perfusion imaging using spoiled gradient echo (sGE) protocols for non-invasive stress-testing.

Methods

From August 2020 to March 2022, N=222 patients with active cardiac implantable electronic devices (CIED) were scanned on a 1.5-T MR scanner (Philips Ingenia and Ambition). Our CMR scanning protocol was tailored to the clinical indication, and whenever myocardial perfusion imaging was possible, both a conventional steady-state-free-precession (SSFP)-based and a modified sGE-perfusion protocol were applied. Such a tailored perfusion protocol was performed in N=119 patients (70% men) with exclusively left-sided devices (pacemaker (PM), n=45; implantable cardioverter-defibrillator (ICD), n=46; subcutaneous ICD (S-ICD), n=15 and cardiac resynchronization therapy-pacemaker (CRT-P, n=5) or -defibrillator (CRT-D, n=8) with a percentage of 10% non-conditional devices. For assessment of image quality, a semi-quantitative 4-point grading scale was used based on a standard 16-segment model.

Results

A total of N=33 stress-tests with either regadenosone, adenosine or dobutamine and N=86 rest perfusion protocols were performed. Asynchronous pacing was required in 34% of the patients due to a heart rate of <40bpm. Device interrogation before and after CMR scanning showed no significant changes. Image quality was substantially better in sGE-based perfusion protocols compared to conventional SSFP-based perfusion in ICD, CRT-D and S-ICD patients (p<0.001). In patients with PM/ CRT-P image quality was neither significantly impaired in SSFP- nor in sGE-based protocols. Most device artefacts were located primarily in the anterior myocardial segments (1, 7, 13) in transvenous implanted devices and lateral in SICD-patients. A significant relationship between the extent of device artefacts and the parameters LVEDV (p=0.03), LVESV (p=0.005) and non-conditional devices (p=0.029) in SSFP-perfusion protocols were found in patients with PM/CRT-P. In contrast, there was no correlation between clinical and CMR-parameters in patients with ICD/ CRT-D. In S-ICD-patients, there was an inverse relationship between the extent of device artefact and age (p=0.006), BMI (p=0.001) in sGE-perfusion.

Conclusion

Myocardial perfusion imaging by CMR is safe and feasible with high image-quality in patients with all kinds of CIEDs – including MR-conditional as well as non-conditional devices. When performing CMR-based myocardial perfusion imaging in patients with left-sided ICD/CRT-D/S-ICD, a sGE-based perfusion-protocol should be preferred compared to conventional SSFP-based perfusion protocols in order to achieve artefact-free and well interpretable images.

Funding Acknowledgement

Type of funding sources: None.

Therapeutic value of tafamidis in patients with wild-type transthyretin amyloidosis (ATTRwt) with cardiomyopathy based on cardiovascular magnetic resonance (CMR) imaging

Background

Tafamidis was approved in Europe for the treatment of cardiomyopathy (CM) in patients with transthyretin amyloidosis (ATTR) in April 2020. So far, real-world data addressing the therapeutic value of tafamidis for the treatment of ATTR-CM are scarce. The purpose of this study was to carefully analyse the therapeutic benefit of tafamidis in patients with wild-type ATTR (ATTRwt) and CM (ATTRwt-CM) after one year of therapy based on serial multi-parametric cardiovascular magnetic resonance (CMR) imaging.

Purpose

The purpose of this study was to carefully analyse the therapeutic benefit of tafamidis in patients with wild-type transthyretin amyloidosis (ATTRwt) and cardiomyopathy (ATTRwt-CM) after one year of therapy based on serial multi-parametric cardiovascular magnetic resonance (CMR) imaging.

Methods

The present study comprised N=40 patients with ATTRwt-CM who underwent two serial multi-parametric CMR studies within a follow-up period of 12±3 months. Baseline (BL) clinical parameters, serum biomarkers and CMR findings were compared to follow-up (FU) values in patients with treated “with” tafamidis 61mg daily (n=20, group A) and those “without” tafamidis therapy (n=16, group B). CMR studies were performed on a 1.5-T system and comprised (amongst others) cine-imaging for assessment of cardiac anatomy and function including 3D longitudinal strain assessment. In addition, a modified Look-Locker inversion recovery (MOLLI) T1-mapping sequence was performed for measurement of pre- and post-contrast myocardial T1-values with additional calculation of extracellular volume fraction (ECV)-values.

Results

While left ventricular ejection fraction (LV-EF), left ventricular mass index (LVMi), left ventricular wall thickness (LVWT), native T1- and ECV-values remained unchanged in the tafamidis group A, a slight reduction in LV-EF (p=0.003) as well as a subtle increase in LVMi (p=0.034), in LVWT (p=0.001), in native T1- (p=0.038) and ECV-values (p=0.017) were observed in the untreated group B. Serum NT-proBNP levels showed an overall increase in both groups, however, with the untreated group B showing a relatively higher increase compared to the treated group A. Assessment of NYHA class did not result in significant intra-group differences when BL were compared with FU, but a trend to improvement in the treated group A compared to a worsening trend in the untreated group B (Δp=0.005).

Conclusion

Tafamidis does not improve cardiac phenotype in patients with ATTRwt-CM after one year of therapy. However, tafamidis seems to slow down cardiac disease progression in patients with ATTRwt-CM compared to those without tafamidis therapy based on multi-parametric CMR data already after one year of therapy.

Funding Acknowledgement

Type of funding sources: None.

Computed tomography-based radiomics decodes prognostic and molecular differences in interstitial lung disease related to systemic sclerosis

Background

Radiomic features calculated from routine medical images show great potential for personalised medicine in cancer. Patients with systemic sclerosis (SSc), a rare, multiorgan autoimmune disorder, have a similarly poor prognosis due to interstitial lung disease (ILD). Here, our objectives were to explore computed tomography (CT)-based high-dimensional image analysis (“radiomics”) for disease characterisation, risk stratification and relaying information on lung pathophysiology in SSc-ILD.

Methods

We investigated two independent, prospectively followed SSc-ILD cohorts (Zurich, derivation cohort, n=90; Oslo, validation cohort, n=66). For every subject, we defined 1355 robust radiomic features from standard-of-care CT images. We performed unsupervised clustering to identify and characterise imaging-based patient clusters. A clinically applicable prognostic quantitative radiomic risk score (qRISSc) for progression-free survival (PFS) was derived from radiomic profiles using supervised analysis. The biological basis of qRISSc was assessed in a cross-species approach by correlation with lung proteomic, histological and gene expression data derived from mice with bleomycin-induced lung fibrosis.

Results

Radiomic profiling identified two clinically and prognostically distinct SSc-ILD patient clusters. To evaluate the clinical applicability, we derived and externally validated a binary, quantitative radiomic risk score (qRISSc) composed of 26 features that accurately predicted PFS and significantly improved upon clinical risk stratification parameters in multivariable Cox regression analyses in the pooled cohorts. A high qRISSc score, which identifies patients at risk for progression, was reverse translatable from human to experimental ILD and correlated with fibrotic pathway activation.

Conclusions

Radiomics-based risk stratification using routine CT images provides complementary phenotypic, clinical and prognostic information significantly impacting clinical decision making in SSc-ILD.

CT-based radiomics decodes phenotypic, prognostic and molecular differences in SSc-ILD, and predicts progression-free survival with a significant impact on future clinical decision making in SSc-ILDhttps://bit.ly/3zPaMOn

Changes in cMRI parameters following a switch to riociguat from phosphodiesterase type 5 inhibitors (PDE5i) in patients with pulmonary arterial hypertension: a REPLACE substudy

Background

The REPLACE study investigated the effect of switching to riociguat (RIO) in patients with pulmonary arterial hypertension receiving PDE5i but still at intermediate risk. The centrally adjudicated composite primary endpoint was clinical improvement in the absence of clinical worsening, where clinical improvement was defined as meeting at least two of the following criteria: 6-minute walk distance (6MWD), increase by ≥10% or ≥30 m from baseline (BL) to Wk 24; World Health Organization functional class (WHO FC) I or II at Wk 24; or N-terminal prohormone of brain natriuretic peptide reduction of ≥30% from BL to Wk 24. Twice as many patients switching to RIO (45/111, 41%) met the primary endpoint compared with those remaining on PDE5i (23/113, 20%); odds ratio (OR): 2.78 (95% confidence interval [CI] 1.53–5.06); p=0.0007.

Purpose

Assess changes in right and left ventricular (RV; LV) function using cardiac magnetic resonance imaging (cMRI) in a subgroup of patients participating in REPLACE.

Methods

REPLACE was a randomised, open-label, 24-week, Phase 4 study (NCT02891850). Patients in WHO FC III, with 6MWD 165–440 m, were randomised to switch to RIO 2.5 mg–max tid or remain on PDE5i. Background endothelin receptor antagonist therapy was permitted in both arms.

cMRI was performed on a subset of patients from the full analysis set as an exploratory substudy. The following parameters were measured at BL and Wk 24: RV and LV end-diastolic and end-systolic volumes (RVEDV; RVESV; LVEDV; LVESV), RV stroke volume and stroke volume index (RVSV; RVSVI), LV stroke volume (LVSV), RV ejection fraction (RVEF), and pericardial effusion.

Results

Twenty-seven patients participated in the cMRI substudy. This comprised 11/111 (10%) patients in the RIO arm (mean [standard deviation {SD}] 40.0 [12.4] years), and 16/113 (14%) patients (mean 44.5 [17.6] years) in the PDE5i arm. Like the main population, the treatment response in the cMRI subpopulation favoured RIO versus PDE5i (OR: 6.11 [95% CI 0.90–41.60]). From BL to Wk 24, RVEDV and RVESV decreased in the RIO treatment arm but increased in the PDE5i treatment arm (Table 1). Similar, but less pronounced, changes were observed for the left ventricle (LVESV, LVEDV). RVSV and RVEF levels were close to normal at BL and did not increase in either arm at Wk 24 (Table 1). Pericardial effusion, which was present in 5 patients in each group at BL, decreased in 1 patient in the RIO arm and no patients in the PDE5i arm.

Conclusions

Decreases in RVEDV and RVESV suggest improvements in cardiac function in the RIO arm compared with the PDE5i arm. Values for RVEF and RVSVI were close to normal at BL and did not change at Wk 24. Improvements in cMRI parameters were in line with the clinical improvement observed in patients switching to RIO in the overall population.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): The REPLACE study was co-funded by Bayer AG (Berlin, Germany) and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (Kenilworth, NJ, USA)

Single π 0 production off neutrons bound in deuteron with linearly polarized photons

The quasifree γ → d → π 0 n ( p ) photon beam asymmetry, Σ , has been measured at photon energies, E γ , from 390 to 610 MeV, corresponding to center of mass energy from 1.271 to 1.424 GeV, for the first time. The data were collected in the A2 hall of the MAMI electron beam facility with the Crystal Ball and TAPS calorimeters covering pion center-of-mass angles from 49 ∘ to 148 ∘ . In this kinematic region, polarization observables are sensitive to contributions from the Δ ( 1232 ) and N(1440) resonances. The extracted values of Σ have been compared to predictions based on partial-wave analyses (PWAs) of the existing pion photoproduction database. Our comparison includes the SAID, MAID and Bonn-Gatchina analyses; while a revised SAID fit, including the new Σ measurements, has also been performed. In addition, isospin symmetry is examined as a way to predict π 0 n photoproduction observables, based on fits to published data in the channels π 0 p , π + n and π - p .

OP0150 MACHINE LEARNING APPROACHES FOR RISK MODELLING IN INTERSTITIAL LUNG DISEASE ASSOCIATED WITH SYSTEMIC SCLEROSIS USING HIGH DIMENSIONAL IMAGE ANALYSIS

Background:

The interstitial lung disease (ILD) associated with connective tissue diseases including systemic sclerosis (SSc) is heterogenous disease characterized by reduced survival of approximately 3 years (1). “Radiomics’’ is a field of research which describes the in-depth analysis of tissues by computational retrieval of high-dimensional quantitative features from medical images (2). Our previous study suggested capacity of radiomics features to differentiate between “high” and “low” risk groups for lung function decline in two independent cohorts (3).

Objectives:

  •bTo develop robust, machine learning (ML) workflow for “radiomics” data in SSc-ILD to select optimal methods for prediction.

  •oTo predict the time to individual lung function decline defined as defined by the time to a relative decline of ≥ 15% in Forced Vital Capacity (FVC)% as previously (3), using workflow.

Methods:

We investigated two cohorts of SSc-ILD: 90 patients (76.7% female, median age 57.5 years) from the University Hospital Zurich and 66 patients (75.8% female, median age 61.0 years) from Oslo University Hospital’s. Patients were retrospectively selected if (3): a) diagnosed with early/mild SSc according to the Very Early Diagnosis of Systemic Sclerosis (VEDOSS) criteria, b) presence of ILD on HRCT as determined by a senior radiologist. For every subject, we defined 1,355 robust radiomic features from HRCT images. The follow-up period was defined as the time interval between baseline visit and the last available follow-up visit.

We have developed a systematic computational workflow to build predictive ML models. To reduce the number of redundant radiomic features, we applied correlation thresholds. We applied distinct methods including 1) Lasso Penalized Regression for feature selection, and 2) Random Forest (RF) for modeling using the R package ‘caret’. To select the optimal ML model, we randomly divided derivation cohort into Training (70%) and Holdout (30%) sets and applied fivefold cross-validation (5kCV) for feature and classifier selection on Training set only.

Results:

We have investigated various methods to select the optimal set of predictive radiomic features. Since the ML model performance is affected by both, feature, and classifier selection, we assessed these factors first.

Results from feature filtering and selection, suggested that the combination of correlation threshold of 0.9 with Lasso regression proved best. As we perform feature selection in 5k CV workflow, features present in at least 2 sets entered model optimization step.

During model selection, we selected RF classifier. We detected positive correlation between actual and predicted values with Spearman’s rho = 0.313, p = 0.167 and Spearman’s rho = 0.341, p = 0.015 in Oslo and Holdout sets respectively, as shown on Figure 1. The percentage of variance remained modest for both Holdout (Rsq = 0.104) and Oslo (Rsq = 0.126) datasets.

Figure 1.

Performance of the best, RF classifier shown as scatterplot between actual and predicted values of individual time to lung decline.

Conclusion:

In summary, we: (1) developed ML workflow that allowed to select o optimal methodology for modeling (i.e., feature and classifier selection), and (2) provide models that predicted time to individual lung function decline, characterized by significant correlation between predicted and actual values.

References:

[1]Hansell DM, Goldin JG, King TE, Jr., Lynch DA, Richeldi L, Wells AU. CT staging and monitoring of fibrotic interstitial lung diseases in clinical practice and treatment trials: a position paper from the Fleischner Society. Lancet Respir Med. 2015;3(6):483-96.

[2]Lambin, P. et al. Radiomics: extracting more information from medical images using advanced feature analysis. Eur. J. Cancer 48, 441–446 (2012).

[3]Schniering J. et al. Resolving phenotypic and prognostic differences in interstitial lung disease related to systemic sclerosis by computed tomography-based radiomics. https://www.medrxiv.org/content/10.1101/2020.06.09.20124800v1

Disclosure of Interests:

None declared

POS0866 TWO-DIMENSIONAL HRCT-BASED RADIOMIC FEATURES IN SSC-ILD DISTINGUISH DRUG RESPONDERS FROM NON-RESPONDERS

Background:

Management of patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) is complicated by high inter-patient variability. To date, no validated predictors of treatment response are available for routine use. High resolution computed tomography (HRCT)-based radiomics, i.e. the high-dimensional, quantitative analysis of imaging metadata, have previously been shown to be successful in discriminating (SSc-)ILD phenotypes in preclinical and clinical studies1. Since HRCT is an integral part of the routine work-up in SSc, HRCT-based radiomic features may hold potential as non-invasive biomarkers.

Objectives:

To predict treatment response using two-dimensional (2D) HRCT-based radiomics in SSc-ILD patients from a prospectively followed cohort.

Methods:

Inclusion criteria were diagnosis of SSc-ILD in HRCT, availability of a suitable chest HRCT scan within 12 months prior to initiation of a new treatment, and availability of clinical baseline and follow-up information. Treatment response was defined as the absence of all of the following over a follow-up period of 12-24 months: relative decrease in forced vital capacity (FVC) ≥5%, increase of ILD in HRCT as assessed by a radiologist, change in treatment regimen due to insufficient response, ILD-related death or lung transplantation. Of each pre-treatment HRCT, 6 slices (15±5 mm apart, starting from the basal lung margin) were manually segmented and 1513 2D radiomic features were extracted using the in-house software Z-Rad (Python 2.7). Features were Z-score transformed and pre-filtered for inter- and intra-reader robustness (intraclass correlation coefficient >0.85) and inter-feature correlation (Spearman’s rho <0.9). A categorical linear regression model was created using 3-fold cross-validated elastic nets for feature selection. Features were then summarized and divided by their number. For generation of a score cut-off, Youden’s score was used. For two-group analyses of continuous variables, Wilcoxon’s test was performed, whereas categorical data was assessed using Fisher’s exact test.

Results:

A total of 64 pre-treatment HRCTs from 54 patients were analyzed. In 9 patients, >1 asynchronous treatments were assessed, while 45 patients had only 1 eligible treatment approach. The response rate within the assessed follow-up period was 45.3% (n=29). For score generation, 13 radiomic features were selected and an optimal cut-off value of -0.1589 was determined. Univariate linear regression showed significant association between our categorical radiomics-based score and treatment response (p=0.007, area under the curve = 0.65 (0.51-0.79), sensitivity=0.90, specificity=0.43), whereby a high score was predictive for treatment response.

No differences between patients with high (n=46) or low (n=18) scores were detected for baseline age (mean±SD=55.5±12.0 and 55.5±13.6 years, p=0.84), duration of SSc (mean±SD=6.2±8.4 and 4.7±4.4 years, p=0.79), time since ILD diagnosis (2.7±2.9 and 2.4±3.1 years, p=0.59), FVC (77.6±20.6 and 80.1±17.9, p=0.41) or DLco (54.4±21.0 and 57.6±18.9, p=0.40). Distribution of anti-Scl-70 positivity (45.7% vs. 55.6%, p=0.58) and diffuse cutaneous disease (47.7% vs. 61.1%, p=0.41) was not significantly different between patients with high and low scores, respectively, although a trend towards higher percentages in the high score group was observed.

Conclusion:

Our results indicate that, following validation in external cohorts, radiomics may be a promising tool for future pre-treatment patient stratification. Moreover, our radiomics-based score seems not to be associated with commonly studied clinical predictors such as anti-Scl-70 positivity or lung function, underlining a possible additive value to ‘traditional’ clinical parameters.

References:

[1]Schniering, J., et al. Resolving phenotypic and prognostic differences in interstitial lung disease related to systemic sclerosis by computed tomography-based radiomics. medRxiv [Preprint] doi:10.1101/2020.06.09.20124800 (2020).

Disclosure of Interests:

Chantal Meier: None declared, Malgorzata Maciukiewicz: None declared, Matthias Brunner: None declared, Janine Schniering: None declared, Hubert Gabrys: None declared, Anja Kühnis: None declared, Oliver Distler Speakers bureau: Speaker fee on Scleroderma and related complications: Bayer, Boehringer Ingelheim, Medscape, Novartis, Roche. Speaker fee on rheumatology topic other than Scleroderma: MSD, iQone, Novartis, Pfizer, Roche, Consultant of: Consultancy fee for Scleroderma and its complications: Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Bayer, Baecon Discovery, Boehringer, CSL Behring, ChemomAb, Corbus Pharmaceuticals, Horizon Pharmaceuticals, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, Kymera, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Roivant Sciences, Sanofi, UCB. Consultancy fee for rheumatology topic other than Scleroderma: Abbvie, Amgen, Lilly, Pfizer, Grant/research support from: Research Grants to investigate the pathophysiology and potential treatment of Scleroderma and its complications: Kymera Therapeutics, Mitsubishi Tanabe, Thomas Frauenfelder: None declared, Stephanie Tanadini-Lang: None declared, Britta Maurer Speakers bureau: Speaker fees from Boehringer-Ingelheim, Grant/research support from: Grant/research support from AbbVie, Protagen, Novartis Biomedical Research, congress support from Pfizer, Roche, Actelion, mepha, and MSD

Serum metabolites as biomarkers in systemic sclerosis-associated interstitial lung disease

Systemic sclerosis (SSc) is a severe multi-organ disease with interstitial lung disease (ILD) being the major cause of death. While targeted therapies are emerging, biomarkers for sub-stratifying patients based on individual profiles are lacking. Herein, we investigated how levels of serum metabolites correlated with different stages of SSc and SSc-ILD. Serum samples of patients with SSc without ILD, stable and progressive SSc-ILD as well as of healthy controls (HC) were analysed using liquid targeted tandem mass spectrometry. The best discriminating profile consisted of 4 amino acids (AA) and 3 purine metabolites. L-tyrosine, L-tryptophan, and 1-methyl-adenosine distinguished HC from SSc patients. L-leucine, L-isoleucine, xanthosine, and adenosine monophosphate differentiated between progressing and stable SSc-ILD. In SSc-ILD, both, L-leucine and xanthosine negatively correlated with changes in FVC% predicted. Additionally, xanthosine was negatively correlated with changes in DLco% predicted and positively with the prognostic GAP index. Validation of L-leucine and L-isoleucine by an enzymatic assay confirmed both the sub-stratification of SSc-ILD patients and correlation with lung function and prognosis score. Serum metabolites may have potential as biomarkers for discriminating SSc patients based on the presence and severity of ILD. Confirmation in larger cohorts will be needed to appreciate their value for routine clinical care.

Ruling in or out the presence of cardiac amyloidosis based on cut-off values using T1-mapping – caution is required regarding the control group

Background

Cardiac amyloidosis (CA) is an infiltrative disease that is characterized by accumulation of amyloid deposits in the interstitium of the myocardium. In contrast, hypertrophic cardiomyopathy (HCM) is caused by a disorganized arrangement of myocyte hypertrophy as well as expanded extracellular matrix, composed of interstitial and replacement fibrosis.

Purpose

A diagnostic algorithm based on (native) T1-mapping using cardiovascular magnetic resonance (CMR) was suggested in a recent study for the diagnosis of CA: A native T1 &lt;1,036ms was mentioned to have a 98% negative predictive value (NPV) for ruling out CA whereas a native T1 &gt;1,164ms showed a 98% positive predictive value (PPV) for the presence of CA. In the present study, we critically addressed the calculation of such cut-off values considering possible differences in the composition of the control group.

Methods

N=30 patients with CA, N=20 patients with HCM and N=15 healthy controls without relevant cardiac disease underwent dedicated CMR studies on a 1.5-T MR scanner. The CMR protocol comprised standard sequences for cine-imaging, native and post-contrast MOLLI-based T1-mapping and late-gadolinium-enhancement (LGE). ECV measurements were based on pre- and post-contrast T1-mapping images.

Results

Native T1 and ECV were significantly increased in CA compared to HCM and receiver operating characteristic (ROC) analyses revealed an area-under-the-curve (AUC) = 0.984 for native T1 (p&lt;0.001) and AUC = 0.985 for ECV (p&lt;0.001) regarding the diagnosis of CA). When CA patients were compared to HCM patients (excluding healthy controls), a native T1 &lt;1,036ms or an ECV &lt;33% were associated with a 99% NPV for ruling out CA whereas a native T1 ≥1,082ms or an ECV ≥41% were associated with a 99% PPV for diagnosis of CA. However, when CA patients were compared to healthy controls (excluding HCM patients), a native T1 &lt;1,025ms or an ECV &lt;34% were associated with a 99% NPV for ruling out CA whereas a native T1 ≥1,025ms or an ECV ≥34% were associated with a 99% PPV for diagnosis of CA since there was no overlap in native T1 and ECV values between CA patients and healthy controls.

Conclusion

Cut-off values for native T1 or ECV derived from ROC analyses (in a specific group of study patients) for ruling in or out the presence of CA are – amongst others - determined by the native T1 and ECV values of the respective “control group”. A different composition of the control group (e.g. HCM patients vs. healthy volunteers) will result in different cut-off values. Hence, previously suggested cut-off values obtained in single center studies need to be considered carefully – with a special attention to the control group of the underlying study – and should not be transferred to other centers carelessly.

Funding Acknowledgement

Type of funding source: None

SAT0333 SERUM METABOLITES AS BIOMARKERS IN SYSTEMIC SCLEROSIS-ASSOCIATED INTERSTITIAL LUNG DISEASE

Background:

In fibrotic diseases, metabolic processes are altered with a tendency towards an anabolic state, which is partially reflected in serum. Circulating biomarkers for interstitial lung disease (ILD), the leading cause of death in systemic sclerosis (SSc), are still sparse and not established in routine care.

Objectives:

To assess the potential of serum metabolites as biomarkers for the presence and progression of SSc-ILD.

Methods:

Age and sex matched serum samples of SSc patients from the Zurich cohort and of healthy controls (HC) were analyzed. Progressive SSc-ILD was defined as either a relative decrease in forced vital capacity (FVC) >10%, a decrease in FVC of 5-9% and a concomitant decrease of carbon dioxide diffusion capacity >15%, or an increase of the extent of lung fibrosis on computed tomography from <20% to ≥20% compared to the last visit (mean follow-up interval = 14 months (range = 9-26)). Sera of HC, non-ILD SSc and stable vs. progressive SSc-ILD patients (n = 12 per group; total n = 48) were screened for 110 metabolites by targeted liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Peak areas were analyzed with R 3.6. For univariate analysis, FDR-corrected one-way ANOVA was used. In multivariate group-wise partial least squares discriminant analysis (PLS-DA), variable importance in the projection (VIP) scores ≥2 were considered significant.

Results:

In total, 85 metabolites were detected. Univariate analysis of all groups were suggestive of changes for 1-methyladenosine, L-tryptophan, L-tyrosine, L-leucine and xanthosine (p = 0.077, 0.028, 0.077, 0.028 and 0.032, respectively). In PLS-DA, HCs and SSc patients differed in their levels of L-tyrosine and L-tryptophan, while levels of L-threonine, 3-aminoisobutyric acid, adenosine monophosphate and xanthosine were changed when comparing non-ILD and SSc-ILD patients. Receiver operating curve (ROC) analysis of significant metabolites from uni- and multivariate testing resulted in separation of SSc patients from HCs by L-tyrosine (area under the curve (AUC) = 0.81, 95% confidence interval (CI): 0.67-0.96), L-tryptophan (AUC = 0.86, CI: 0.75-0.97) and 1-methyladenosine (AUC = 0.82, CI: 0.71-0.94). Progressive SSc-ILD patients were separated from stable patients by their levels of L-isoleucine, L-leucine, adenosine monophosphate and xanthosine (AUC = 0.83, 0.85, 0.79 and 0.77; CI: 0.66-1.00, 0.70-1.00, 0.60-0.97 and 0.55-0.99, respectively). Validation of increased values of the branched-chain amino acids L-leucine and L-isoleucine in progressive SSc-ILD vs. stable ILD using an enzymatic assay resulted in similar results as LC-MS/MS analysis, with higher values detected in progressive vs. stable patients (mean = 286.5 and 235.5 nM, respectively; p = 0.005). In ROC analysis (AUC = 0.81, CI: 0.62-1.00), a cut-off value of 250.3 nM separated stable from progressive patients with a sensitivity of 72.7% and a specificity of 83.3%.

Conclusion:

This study in SSc(-ILD) patients suggested alterations in serum metabolite levels corresponding with their current state of disease, indicating the potential use of serum metabolites as discriminating biomarkers upon further confirmation in larger multicenter studies.

Disclosure of Interests:

Chantal Meier: None declared, Katrin Freiburghaus: None declared, Cédric Bovet: None declared, Janine Schniering: None declared, Oliver Distler Grant/research support from: Grants/Research support from Actelion, Bayer, Boehringer Ingelheim, Competitive Drug Development International Ltd. and Mitsubishi Tanabe; he also holds the issued Patent on mir-29 for the treatment of systemic sclerosis (US8247389, EP2331143)., Consultant of: Consultancy fees from Actelion, Acceleron Pharma, AnaMar, Bayer, Baecon Discovery, Blade Therapeutics, Boehringer, CSL Behring, Catenion, ChemomAb, Curzion Pharmaceuticals, Ergonex, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Sanofi and UCB, Speakers bureau: Speaker fees from Actelion, Bayer, Boehringer Ingelheim, Medscape, Pfizer and Roche, Christos Nakas: None declared, Britta Maurer Grant/research support from: AbbVie, Protagen, Novartis, congress support from Pfizer, Roche, Actelion, and MSD, Speakers bureau: Novartis

Favipiravir strikes the SARS-CoV-2 at its Achilles heel, the RNA polymerase

The ongoing Corona Virus Disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emphasized the urgent need for antiviral therapeutics. The viral RNA-dependent-RNA-polymerase (RdRp) is a promising target with polymerase inhibitors successfully used for the treatment of several viral diseases. Here we show that Favipiravir exerts an antiviral effect as a nucleotide analogue through a combination of chain termination, slowed RNA synthesis and lethal mutagenesis. The SARS-CoV RdRp complex is at least 10-fold more active than any other viral RdRp known. It possesses both unusually high nucleotide incorporation rates and high-error rates allowing facile insertion of Favipiravir into viral RNA, provoking C-to-U and G-to-A transitions in the already low cytosine content SARS-CoV-2 genome. The coronavirus RdRp complex represents an Achilles heel for SARS-CoV, supporting nucleoside analogues as promising candidates for the treatment of COVID-19.

Circulating biomarkers of systemic sclerosis - interstitial lung disease

Interstitial lung disease is a frequent organ manifestation in systemic sclerosis and is associated with high mortality. It is crucial to diagnose interstitial lung disease in systemic sclerosis and to assess severity and identify patients prone to progression at an early stage to ultimately decrease organ damage and improve outcome. Circulating anti-topoisomerase-I autoantibodies have long been associated with the presence and development of systemic sclerosis - interstitial lung disease, evidence on their potential to further predict the clinical course of systemic sclerosis is however conflicting. C-reactive protein is a marker of infection and systemic inflammation with widespread clinical application and is elevated in systemic sclerosis with a tendency towards higher abundancy in patients with early disease. The role of other circulating biomarkers is promising but hampered by the lack of standardized criteria and guidelines for sample/data collection, analyses, reporting and validation and has not reached prime time for clinical application. However, epithelial markers including Krebs von den Lungen-6 and surfactant protein D and several cytokines and chemokines including CCL2 and CCL18 for severity assessment of systemic sclerosis - interstitial lung disease patients at the time of interstitial lung disease diagnosis and to predict interstitial lung disease progression have been reported and seem to be promising candidate biomarkers in the future.

P5274Characterization of cardiac involvement in patients with MELAS syndrome in comparison to HCM patients by conventional LGE imaging and novel T1-mapping

Background

MELAS syndrome (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) is a rare clinical subtype of mitochondrial myopathy. Cardiovascular magnetic resonance (CMR) images of MELAS-patients at an advanced state of the disease often show characteristic patterns: septal pronounced left ventricular (LV) hypertrophy and distinct focal myocardial scars in late-gadolinium-enhancement (LGE) images. This specific pattern is different from those seen in patients with hypertrophic cardiomyopathy (HCM) due to sarcomere protein mutations. Besides LGE imaging another method for the assessment of myocardial integrity, T1-mapping, has been established recently. This is the first study comparing native and enhanced T1-mapping (T1-na/en) as well as extracellular volume (ECV) values in HCM and MELAS.

Methods

12 patients with confirmed MELAS syndrome at different states of the disease, 13 HCM patients and 15 controls were included. All CMR studies were performed on a 1.5T MR scanner (Ingenia, Philips) using bSSFP cine sequences for the assessment of LV-function and MOLLI sequences for T1-na/en mapping. 15min after IV injection of 0.1mmol/kg BW Gadobutrol for LGE imaging, T1-en maps were acquired. For comparison of groups T1-na/en and ECV values in a basal short axis slice were used.

Results

Median and interquartile ranges of LV function, T1 and ECV are shown in the table. There was no difference in LV ejection fraction (LVEF) between the groups, but end-diastolic LV-mass was increased in HCM- and MELAS-patients vs. controls (p<0.001, p=0.028). In MELAS-patients, myocardial fibrosis was detected in focal spots clearly defined in both septum and free lateral wall. In HCM patients there was a rather diffuse LGE pattern in the hypertrophic septum and the RV insertion points. Here T1-na/en and ECV significantly differed from those measured in healthy controls (p<0.001, p<0.001, p=0.002). In the MELAS group T1-na values were significantly higher compared to controls (p=0.004) and significantly lower compared to HCM patients (p=0.003).

LV-function and mapping parameters of compared groups LV-EF, % LV-EDV, ml/m2 LV-mass, g/m2 T1-na, ms T1-en, ms ECV, % MELAS 57 (44–63) 86 (81–122) 80 (50–131) 969 (940–1033) 409 (381–465) 27 (24–35) HCM 60 (57–65) 50 (73–94) 94 (72–102) 1041 (1021–1074) 362 (346–430) 31 (28–36) Controls 61 (58–65) 72 (67–89) 53 (42–60) 937 (894–951) 464 (446–513) 26 (24–27)

Conclusion

Compared to healthy controls and HCM-patients, cardiac involvement in MELAS-patients is not only reliably visualized by conventional LGE imaging but also detected without the use of contrast agent by native T1-mapping. MELAS vs. HCM-patients show a different pattern of LGE and higher native T1 values, respectively.

P608Exercise testing and multi-parametric CMR assessment in patients with Ebstein anomaly

Background

Ebstein anomaly (EA) is a rare congenital heart disease characterized by an apically displaced tricuspid valve. It is associated with tricuspid valve regurgitation and right heart dilatation leading to significant morbidity. While echocardiography remains the mainstay of routine outpatient cardiac imaging, assessment of right ventricular (RV) anatomy and function is still challenging. Cardiovascular magnetic resonance imaging (CMR) has been shown to be of advantage in these patients being free from acoustic window limitations and offering superior volume quantification. In the present study, parameters obtained from cardiopulmonary exercise testing (CPET) were compared to conventional and novel CMR parameters in patients with EA.

Methods

In this prospective single centre study, N=17 patients with EA (mean age = 33.8±12.7yrs; N=10 females) underwent clinical assessment, CPET and multi-parametric CMR. Maximal work load (maxWL) and peak oxygen uptake (maxO2) were derived from CPET. CMR studies were performed on a 1.5-T Philips scanner and respective CMR parameters comprised a) anatomical, b) functional and c) myocardial deformation values of both ventricles.

Results

The majority of patients presented in NYHA class I or II (mean NYHA = 1.6±0.7) and with normal or mildly elevated NT-proBNP values (mean NT-proBNP = 189±158pg/ml). CPET-based maxWL was 147.14±55 watts and maxO2 19.32±5 ml/kg/min. CMR-based mean LVEF was 57.1±6.4% and RVEF was 46.5±11.1%, respectively. Deformation imaging revealed (amongst others) a LV global longitudinal strain (LV-gLS) of −13.7±3.0 and a RV global longitudinal strain (RV-gLS) of −14.7±5.0. Non-ischemic presence of late-gadolinium-enhancement was documented in 36% of our patients. Comprehensive correlation analysis revealed a substantial correlation a) between LV-gLS and NYHA class (r=0.64, p=0.01), but not between RV-gLS and NYHA class (r=0.19, p=0.46), b) between serum NT-proBNP levels and maxO2 (r=−0.53, p=0.03) as well as maxWL (r=−0.63, p=0.02), and c) between LV-EF and LV-gLS (r=−0.64, p=0.01).

Conclusion

Our preliminary data suggest that serum markers such as NT-proBNP and novel CMR parameters such as LV-gLS – but not RV-gLS - correlate with CPET-derived exercise parameters in patients with EA. The predictive value of these parameters regarding cardiac disease progression in EA has to be evaluated in future follow-up studies.

Diagnosis, prevention, and treatment of bone fragility in people living with HIV: a position statement from the Swiss Association against Osteoporosis

Life expectancy of people living with HIV (PLWH) is reaching similar length as in the general population. Accordingly, age-related comorbidities, including osteoporosis, are increasing. Fracture risk is higher and increases approximately 10 years earlier in PLWH. Classical risk factors of bone fragility are highly prevalent in PLWH but factors specific for HIV infection itself and the type of antiretroviral therapy (ART) (triple combination antiretroviral therapy) regimen (especially tenofovir and protease inhibitors) also contribute to bone loss. The majority of bone loss occurs during virus activity and at initiation of ART (immune reconstitution) and is associated with an increase of bone resorption (upregulation RANKL). Recent data indicate that calcium and vitamin D supplements as ART initiation lower BMD loss. The reduction of tenofovir plasma concentrations with tenofovir alafenamide attenuates BMD loss but it remains unknown whether it will contribute to reduce fracture risk. Hence, special considerations for the management of bone fragility in PLWH are warranted. Based on the current state of epidemiology and pathophysiology of osteoporosis in PLWH, we provide the consensus of the Swiss Association against Osteoporosis on best practice for diagnosis, prevention, and management of osteoporosis in this population. Periodic assessment of fracture risk is indicated in all HIV patients and general preventive measures should be implemented. All postmenopausal women, men above 50 years of age, and patients with other clinical risk for fragility fractures qualify for BMD measurement. An algorithm clarifies when treatment with bisphosphonates and review of ART regimen in favour of more bone-friendly options are indicated.

Intestinal vitamin D receptor modulates lipid metabolism, adipose tissue inflammation and liver steatosis in obese mice

OBJECTIVE

Hypovitaminosis D is common in the obese population and patients suffering from obesity-associated disorders such as type 2 diabetes and fatty liver disease, resulting in suggestions for vitamin D supplementation as a potential therapeutic option. However, the pathomechanistic contribution of the vitamin D-vitamin D receptor (VDR) axis to metabolic disorders is largely unknown.

METHODS

We analyzed the pathophysiological role of global and intestinal VDR signaling in diet-induced obesity (DIO) using global Vdr-/- mice and mice re-expressing an intestine-specific human VDR transgene in the Vdr deficient background (Vdr-/- hTg).

RESULTS

Vdr-/- mice were protected from DIO, hepatosteatosis and metabolic inflammation in adipose tissue and liver. Furthermore, Vdr-/- mice displayed a decreased adipose tissue lipoprotein lipase (LPL) activity and a reduced capacity to harvest triglycerides from the circulation. Intriguingly, all these phenotypes were partially reversed in Vdr-/- hTg animals. This clearly suggested an intestine-based VDR activity on systemic lipid homeostasis. Scrutinizing this hypothesis, we identified the potent LPL inhibitor angiopoietin-like 4 (Angptl4) as a novel transcriptional target of VDR.

CONCLUSION

Our study suggests a VDR-mediated metabolic cross-talk between gut and adipose tissue, which significantly contributes to systemic lipid homeostasis. These results have important implications for use of the intestinal VDR as a therapeutic target for obesity and associated disorders.

Intestinal IMINO transporter SIT1 is not expressed in human newborns

The expression of amino acid transporters in small intestine epithelia of human newborns has not been studied yet. It is further not known whether the maturation of imino acid (proline) transport is delayed as in the kidney proximal tubule. The possibility to obtain small intestinal tissue from patients undergoing surgery for jejunal or ileal atresia during their first days after birth was used to address these questions. As control, adult terminal ileum tissue was sampled during routine endoscopies. Gene expression of luminal imino and amino acid transporter SIT1 (SLC6A20) was approximately threefold lower in newborns versus adults. mRNA levels of all other luminal and basolateral amino acid transporters and accessory proteins tested were similar in newborn mucosa compared with adults. At the protein level, the major luminal neutral amino acid transporter B⁰AT1 (SLC6A19) and its accessory protein angiotensin-converting enzyme 2 were shown by immunofluorescence to be expressed similarly in newborns and in adults. SIT1 protein was not detectable in the small intestine of human newborns, in contrast to adults. The morphology of newborn intestinal mucosa proximal and distal to the obstruction was generally normal, but a decreased proliferation rate was visualized distally of the atresia by lower levels of the mitosis marker K_i-67. The mRNA level of the 13 tested amino acid transporters and accessory proteins was nonetheless similar, suggesting that the intestinal obstruction and interruption of amniotic fluid passage through the small intestinal lumen did not affect amino acid transporter expression. NEW & NOTEWORTHY System IMINO transporter SIT1 is not expressed in the small intestine of human newborns. This new finding resembles the situation in the proximal kidney tubule leading to iminoglycinuria. Lack of amniotic fluid passage in small intestinal atresia does not affect amino acid transporter expression distal to intestinal occlusion.

DVO Leitlinie 2017 zur Prophylaxe, Diagnostik und Therapie der Osteoporose bei postmenopausalen Frauen und Männern

Diese DVO Leitlinien, die in erster Linie für Allgemeinmediziner und Spezialisten für Knochenerkrankungen bestimmt sind, sollten von allen im klinischen und ambulanten Bereich tätigen medizinischen Fachkräften angewendet werden. Ziel der Leitlinie ist die Verbesserung der Diagnose, Prävention und Behandlung von Osteoporose und der Folgen der Erkrankung auf der Grundlage evidenzbasierter Medizin.

Klare Empfehlungen, welche Patienten zu diagnostizieren und behandeln sind (basierend auf Risikofaktoren [einschließlich sekundärer Osteoporose]) sowie Primär-, Sekundär- oder Tertiärprävention werden dargestellt, mit dem Schwerpunkt auf der postmenopausalen Osteoporose und der Osteoporose bei Männern.

Die Identifizierung von Patienten mit einem hohen Risiko für Frakturen wird hervorgehoben, und spezifische Schwellenwerte für die Intervention sind definiert (20 % Hüftfrakturrisiko innerhalb von 10 Jahren diagnostischer Schwellenwert, 30 % Hüftfrakturrisiko innerhalb von 10 Jahren therapeutische Schwelle). Die Diagnose von Osteoporose basiert auf der Anamnese des Patienten, der körperlichen Untersuchung, dem Funktionstest (z. B. Timed Up and Go Test), konventionellen Röntgenaufnahmen der Brust- und Lendenwirbelsäule und der Bestimmung der Knochenmineraldichte (BMD) durch das DXA Verfahren.

Die Anamnese ist entscheidend für die Abschätzung des Frakturrisikos auf der Grundlage von 40 wissenschaftlich überprüften Risikofaktoren, die das Frakturrisiko mindestens verdoppeln (z. B. Begleiterkrankungen, Hüftfrakturen in der Familie, prävalente Frakturen an jedem Ort, Lebensstil, Anwendung von Medikamenten, körperliche Aktivität und Stürze). Röntgenaufnahmen der Brust- und Lendenwirbelsäule sind wichtig, um prävalente Wirbelkörperfrakturen zu erkennen. Beim Fehlen eines großen Traumas kann jede Fraktur bei Erwachsenen über dem Alter von 50 Jahren eine Diagnose von Osteoporose nahelegen, mit dem höchsten Risiko für eine nachfolgende Fraktur innerhalb einer kurzen Zeit nach der ersten Fraktur. BMD-Messungen mit DXA sind wichtig, um das individuelle Frakturrisiko besser abschätzen zu können. Eine grundlegende Laboruntersuchung ist obligatorisch, um verschiedene Formen der sekundären Osteoporose ausschließen zu können.

Der DVO-Patientenfindungs-Algorithmus basiert auf dem Geschlecht, Alter, Knochenmineraldichte und vorbestehenden Frakturen als wichtigste Informationen. Die Indikation für eine aktive anti-osteoporotische Therapie kann durch multiple Risikofaktoren modifiziert und verfeinert werden. Dieser Algorithmus wurde seit dem Richtlinien-Update 2006 verwendet und wurde entsprechend der internationalen Literatur zu Risikofaktoren für Osteoporose und osteoporotische Frakturen aktualisiert und angepasst.

Die Behandlung der Osteoporose enthält viele Therapiepfeiler. Zusammen mit Empfehlungen für Bewegung, Physiotherapie und Sturzprävention sowie Ernährung (z. B. Calcium, Vit. D), werden pharmakologische Behandlungen basierend auf evidenzbasierter Medizin empfohlen. Die aktiven Anti-Osteoporose-Medikamente müssen für die Indikation postmenopausale Osteoporose und männliche Osteoporose in Deutschland, Österreich und der Schweiz zugelassen sein. Das Management und die Vorbeugung von häufigen oder seltenen Nebenwirkungen aufgrund von Anti-Osteoporose-Behandlungen, die in der klinischen Praxis angewendet werden, werden ebenfalls detailliert behandelt.

Abstract P4-05-02: Differential regulation of ER protein-turnover in invasive lobular carcinoma cells

Background: Invasive lobular breast carcinoma (ILC) accounts for 10-15% of breast cancers diagnosed annually. ILCs are more likely to be positive (90-95%) for ER compared to IDC (60-70%), and there is some evidence that endocrine treatment response might be different in patients with IDC vs ILC. We asked the question whether there were differences in ER protein steady state levels, and/or turn-over rates.

Methods: We utilized TCGA dataset to compare ESR1 mRNA and ER protein levels between ER+ ILC (n=137) and IDC (n=554). ER H-scores and ESR1 mRNA levels were analyzed from patients with ER+ ILC (n=143) and IDC (n=877) seen at UPMC Magee Women's Hospital. Correlation analysis with Pearson's (r) and Spearman's rank order coefficient (ρ) was used to study the relationship between mRNA and protein levels. Basal and ligand induced ESR1 mRNA and ER protein expression and turn-over were determined in a panel of estrogen responsive ER+ IDC (MCF-7, T47D and ZR75-1) and ILC (BCK-4, MDA-MB-134 VI (MM134), SUM44PE) cell lines to identify potential mechanisms that can contribute to differential expression of ERα protein.

Results: TCGA database analysis revealed significantly lower ESR1 mRNA and ER protein levels in ER+ ILC compared to IDC tumors. Analysis of data from our Magee hospital showed similar ER IHC H-scores for ER+ ILCs and IDCs despite having significantly lower ESR1 mRNA in ILC. In both the study sets, the correlation between ER mRNA and protein levels were found to be significantly weaker in ER+ ILC than IDC suggesting subtype specific increased synthesis and/or stability of the receptor protein. ILC cell lines MM134 and SUM44 have increased levels of ER protein compared to IDC cell lines. Estradiol decreased the levels and half-life of ER protein in all IDC cell lines tested. In MM134 and SUM44PE ILC cell lines, estradiol decreased the rate of degradation of ER and increased its half-life. In MM134 cells, treatment with estradiol induced a dose- and time-dependent increase in ER, which is associated with a sustained level of elevated phosphorylation at Ser 118.

Conclusions and ongoing/future studies: The estradiol-induced ER protein stability in a subset of ILC cell lines suggest a possible mechanism leading to weaker ER mRNA-protein correlation in ILC tumors. We currently do not know if and how this observation might be linked to antiestrogen response in ILC. We have recently initiated a TBCRC-supported trial in which we will compare the effect of different endocrine therapies in patients with ILC. Access to pre and post therapy samples will provide the opportunity to study ER levels and its downstream signaling as a function of antiestrogen treatment.

Citation Format: Jankowitz RC, Sreekumar S, Levine KM, Meier C, Sikora MJ, Basudan A, Boone D, Dabbs DJ, Jacobsen B, Lee AV, Oesterreich S. Differential regulation of ER protein-turnover in invasive lobular carcinoma cells [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-05-02.

Abstract P5-06-03: Generation and characterization of a novel invasive lobular breast carcinoma cell line WCRC-25

Background: Invasive Lobular Breast Carcinoma (ILC) is the second most common histologic subtype of breast cancer, comprising 10-15% of all cases. ILC is clinically and molecularly distinguished from the major subtype–Invasive Ductal Carcinoma (IDC)–by loss of E-cadherin (CDH1). Studies on ILC remain sparse, in part due to limited cell culture models. The Women's Cancer Research Center (WCRC) has therefore set up a combined effort of breast surgical oncologists, medical oncologists, pathologists, and cancer biologists to collect fresh tissues and establish additional ILC cell lines.

Methods: Tumor cells were grown using irradiated fibroblast conditioned media (CM) in hypoxic (5% O2) conditions. Sanger sequencing and Droplet Digital PCR (ddPCR) were utilized to test for mutation in CDH1 in tumor and circulating DNA (cfDNA), using germline DNA as control. DNA copy number status in the tumor was detected using nanoString approach. Expression of E-cadherin and a series of lineage markers was elucidated using Immunoblotting (IB) and Immunofluorescence (IF). A panel of ILC (MDA-MB-134, Sum44PE, IPH-926) and IDC (MCF-7, MDA-MB-231) cell lines was included for comparison. After establishment, WCRC-25 population doubling was compared between growth in CM or Dulbecco's Modified Eagle's Medium (DMEM), and hypoxic (5% O2) or normoxic (21% O2) conditions. Growth phenotypes were characterized in 2D, Ultra Low Attachment (ULA), and soft agar.

Results: WCRC-25 was successfully established from the pleural effusion of a 77-year old patient with metastatic ILC. The patient had stage IV (T3N3M1) ER+/PR-/HER2- ILC; was treated with bilateral mastectomy, radiation therapy, and multiple lines of chemotherapy (FOLFOX due to initial misdiagnosis; 2 cycles carboplatin/paclitaxel; anastrazole, fulvestrant, pegylated liposomal doxorubicin, gemcitabine, exemastane, and eribulin (with denosumab for bone lesions); had metastatic lesions in stomach, bone, pleura, and pericardium; and ultimately passed away from progressive pleural effusions roughly 3 years after diagnosis. A novel nonsense mutation of CDH1 was observed in exon 13 (Q705*) in cell line DNA, resulting in a premature stop codon. The same mutation was confirmed in cfDNA obtained from longitudinal blood samples from the patient. Copy number analysis revealed deletion of the second CDH1 copy in tumor, and E-cadherin protein loss was confirmed by IB and IF. WCRC-25 cells expressed epithelial cell markers CK8/18 and EpCAM, and as expected did not express stromal marker αSMA. ERα expression was very low, and not sufficient for measurable hormone response. Population doubling was significantly faster in hypoxic compared to normoxic conditions, regardless of media type, but minimal in 3D.

Conclusions: WCRC-25 is a novel ILC cell line, defined by CDH1 nonsense truncating mutation and LOH, resulting in loss of E-cadherin protein expression. Cells show favorable growth characteristics in hypoxic conditions and maintain epithelial-dominated protein expression. We are currently performing RNA seq analysis of the matched primary tumor and metastatic samples from the stomach, peritoneum/falciform ligament, pleural effusion and skin, which we will compare and contrast with that of the established WCRC-25 cell line.

Citation Format: Kota K, Bossart E, Basudan A, Minteer T, Meier C, Brown D, Gurda GT, Miller L, Dabbs DJ, Lee A, Puhalla S, Jankowitz R, McAuliffe P, Lucas P, Oesterreich S. Generation and characterization of a novel invasive lobular breast carcinoma cell line WCRC-25 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-06-03.

Electromagnetic disturbances rejection with single skin contact in the context of ECG measurements with cooperative sensors

Classical approaches to make high-quality measurements of biopotential signals require the use of shielded or multi-wire cables connecting the electrodes to a central unit in a star arrangement. Consequently, increasing the number of leads increases cabling and connector complexity which is not only limiting patient comfort but also anticipated as the main limiting factor for future miniaturization and cost reduction of tomorrow's wearables. We have recently introduced a novel sensing architecture that significantly reduces cabling complexity by eliminating shielded or multi-wire cables as well as by allowing simple connectors thanks to a bus arrangement. In this architecture, electrodes are replaced by so-called cooperative sensors. However, in this design, one of the cooperative sensors needs to be equipped with two contacts with the skin for proper common mode rejection, thus making its miniaturization problematic. This paper presents a novel common mode rejection principle which overcomes this limitation. When compared to others, the suggested approach is advantageous as it keeps the cabling complexity to its minimum. First measurements demonstrated in a real-life scenario the feasibility of this common mode rejection principle for a wearable 12-lead electrocardiogram monitoring system.

Zn-VI quasiparticle gaps and optical spectra from many-body calculations

The electronic band structures of hexagonal ZnO and cubic ZnS, ZnSe, and ZnTe compounds are determined within hybrid-density-functional theory and quasiparticle calculations. It is found that the band-edge energies calculated on the [Formula: see text] (Zn chalcogenides) or GW (ZnO) level of theory agree well with experiment, while fully self-consistent QSGW calculations are required for the correct description of the Zn 3d bands. The quasiparticle band structures are used to calculate the linear response and second-harmonic-generation (SHG) spectra of the Zn-VI compounds. Excitonic effects in the optical absorption are accounted for within the Bethe-Salpeter approach. The calculated spectra are discussed in the context of previous experimental data and present SHG measurements for ZnO.

Bone morphogenetic protein 2/SMAD signalling in human ligamentocytes of degenerated and aged anterior cruciate ligaments

OBJECTIVE

Anterior cruciate ligament (ACL) degeneration leads to knee instability and favors osteoarthritis (OA) progression. During ageing the growth factor sensitivity of ligaments changes but nothing is known about BMP2-signalling and -sensitivity in degenerated ACLs. This study addressed the question whether a dysregulated BMP2 signalling might contribute to age- and OA-dependent ACL degeneration.

METHOD

ACL samples from patients with/without OA of different ages (<60 and ≥60 years, males, females) were graded histopathologically (n = 45). After stimulation of cultured ACL fibroblasts with 5 nM BMP2 for different time points, phosphorylation of SMAD1/5/8 and gene expression of crucial BMP2 signalling proteins, ligamentogenic and chondrogenic transcription factors, scleraxis (SCX) and SOX9, were analyzed.

RESULTS

ACL samples displayed different grades of degeneration, often associated with synovitis and calcium deposits. Degeneration correlated significantly with synovitis. ACL fibroblasts expressed BMP type I receptors ALK3 and ALK6 and the BMP type II receptor BMPRII. Donors could be divided into "responders" and "non responders" since their BMP2 mediated SMAD1/5/8 phosphorylation level differed. Basal ID1 expression was lower in cells derived from OA compared with non-OA patients and BMP2 led to an ID1 induction in both. Irrespective of BMP2 stimulation, the donor age significantly influenced the expression profile of BMP6 and SCX but not BMP signalling. The BMP2-mediated SMAD6 expression differed between OA and healthy ACL fibroblasts.

CONCLUSION

Our data indicate that the expression level of BMP2/SMAD target genes such as ID1 and SMAD6 was reduced in ACL fibroblasts derived from OA compared with non OA patients.

Rational Development of Nucleoside Diphosphate Prodrugs: DiPPro-Compounds

The bio-reversible protection of nucleoside diphosphates is summarized. The design, hydrolytic characteristics, and the antiviral activity of these prodrugs of NDPs are described. In contrast to earlier attempts, the DiPPro-approach [β-(bis(acyloxybenzyl) nucleoside diphosphates)] leads to the successful delivery of the desired nucleoside diphosphates. The stability towards hydrolysis is dependent on the specific acyl moieties in the bis(acyloxybenzyl) unit as well as on the particular nucleoside analogue. Hydrolysis studies in aqueous PBS buffer (pH 7.3), 20 % human plasma in PBS, RPMI-1640 culture medium, and CEM cell extracts were carried out. Contrary to a high chemical and plasma stability, the compounds showed a very low half-life in CEM cell extracts, and efficiently released the nucleoside analogues diphosphates, e.g. of AZT, d4T and BVDU. Two additional types of cycloSal- NDP prodrugs were studied but neither proved to be useful as nucleoside diphosphate prodrugs. In summary, the results led to the development of a new series of non-symmetric nucleoside diphosphate prodrugs that selectively delivered the nucleoside diphosphate in cell extracts.

Enhancing High-Order Harmonic Generation in Light Molecules by Using Chirped Pulses

One of the current challenges in high-harmonic generation is to extend the harmonic cutoff to increasingly high energies while maintaining or even increasing the efficiency of the high-harmonic emission. Here we show that the combined effect of down-chirped pulses and nuclear dynamics in light molecules allows one to achieve this goal, provided that long enough IR pulses are used to allow the nuclei to move well outside the Franck-Condon region. We also show that, by varying the duration of the chirped pulse or by performing isotopic substitution while keeping the pulse duration constant, one can control the extension of the harmonic plateau.

Maternal Serum Screening in Ontario Using the Triple Marker Test

Objectives:

To summarise the experience and evaluate the performance of the Ontario maternal serum screening (MSS) programme.

Methods:

This study used information collected in the Ontario MSS database, which contains data on each screened pregnancy. In the Ontario MSS programme, women are screened between 15 and 20 weeks of gestation. The risk cut-off for Down's syndrome was ≥1 in 385 at term and women with a serum alpha-fetoprotein ≥2.2 multiples of the unaffected population median were defined as screen-positive for open neural tube defects.

Results:

Between 1 October 1993 and 30 September 2000, 428,410 women residing in Ontario were screened for open neural tube defects, and 423,895 women were screened for Down's syndrome and trisomy 18. Approximately 48% of all pregnant women in the province had MSS. The uptake rate of amniocentesis following a positive Down's syndrome screening was 67%. Of 717 cases of Down's syndrome ascertained in the screened population, 531 were detected by MSS, giving a term detection rate (DR) of 70.6%, with a false-positive rate (FPR) of 7.2%. For neural tube defects, the DRwas 72.7%, with a FPR of 2.0%. The screen also detected 50% of cases of trisomy 18 at term, with a FPR of 0.2%. Coincidentally, 113 cases of chromosome aneuploidies other than Down's syndrome and trisomy 18 were detected

Discussion:

In the Ontario MSS programme, MSS performed as expected in the detection of Down's syndrome, open neural tube defects and trisomy 18. MSS is an effective and practical method for large- scale second ttrriimester screeni.ng for Down's syndrome, open neuraI tube defects and ttrriisomy 18, and the MSS database is an extremely useful tool in monitoring the performance of this screen.

Clinical presentation and management of patients with primary hyperparathyroidism of the Swiss Primary Hyperparathyroidism Cohort: a focus on neuro-behavioral and cognitive symptoms

PURPOSE

To describe the clinical and biochemical profile of patients with primary hyperparathyroidism (PHPT) of the Swiss Hyperparathyroidism Cohort, with a focus on neurobehavioral and cognitive symptoms and on their changes in response to parathyroidectomy.

METHODS

From June 2007 to September 2012, 332 patients were enrolled in the Swiss PHPT Cohort Study, a nationwide prospective and non-interventional project collecting clinical, biochemical, and outcome data in newly diagnosed patients. Neuro-behavioral and cognitive status were evaluated annually using the Mini-Mental State Examination, the Hospital Anxiety and Depression Scale, and the Clock Drawing tests. Follow-up data were recorded every 6 months. Patients with parathyroidectomy had one follow-up visit 3-6 months' postoperatively.

RESULTS

Symptomatic PHPT was present in 43 % of patients. Among asymptomatic patients, 69 % (131/189) had at least one of the US National Institutes for Health criteria for surgery, leaving thus a small number of patients with cognitive dysfunction or neuropsychological symptoms, but without any other indication for surgery. At baseline, a large proportion showed elevated depression and anxiety scores and cognitive dysfunction, but with no association between biochemical manifestations of the disease and test scores. In the 153 (46 %) patients who underwent parathyroidectomy, we observed an improvement in the Mini-Mental State Examination (P = 0.01), anxiety (P = 0.05) and depression (P = 0.05) scores.

CONCLUSION

PHPT patients often present elevated depression and anxiety scores and cognitive dysfunction, but rarely as isolated manifestations. These alterations may be relieved upon treatment by parathyroidectomy.

Reduction Techniques for Trochantericand Subtrochanteric Fractures of the Femur: a Practical Guide

Trochanteric intramedullary nailing has gained widespread acceptance and popularity among orthopedic trauma surgeons. Whereas some simple fracture patterns are easily reduced and nailed, others may present a major challenge for the surgeon. Anatomical reduction and optimal placement of the intramedullary implants are the most important factors for fracture healing and good functional outcome. Closed anatomical reduction is to be achieved before the nail is inserted. However, especially in inter- and subtrochanteric fractures, a limited open or even open reduction technique may be necessary to achieve an adequate reduction. This article focuses on a structured and practical approach to various reduction techniques based on characteristic displacement patterns. The authors describe in detail their favored reduction techniques with tips and tricks for problem-solving. Furthermore, a non-systematic review of the current literature is provided with a critical appraisal of the described techniques and alternative methods. Key words: trochanteric, subtrochanteric femur, fracture, reduction, cephalomedullary nail.

[FLS - three letters alter secondary fracture prevention]

The increasing importance of preventive measures in the field of orthopedics and trauma surgery becomes apparent because of the demographic changes and the high risk for secondary fractures following osteoporotic fractures. Within the fracture treatment chain, orthopedics and trauma surgery are in the "pole position" to initiate these measures in geriatric patients. In the past orthopedists and trauma surgeons have constantly accused of neglecting secondary fracture prevention in fragility fracture patients. There are several reasons that speak in favor of us undertaking a role in secondary fracture prevention: osteoporosis medication is highly effective in fracture prevention when correctly indicated, the positive effects of osteoporosis therapy on fracture healing and legal issues. Arguments that have been used to justify neglect of secondary fracture prevention are undesired side effects related to osteoporosis medications, such as atypical femoral fractures and osteonecrosis of the jaws, interference of some specific drugs with fracture healing and the working conditions in emergency departments. These run contrary to the consideration of chronic diseases such as osteoporosis, secondary osteoporosis and the underlying disease could be overlooked and the increasing complexity of medicinal osteoporosis therapy. In the first part of the article these arguments are weighed against each other. In the second part the concept of a fracture liaison service (FLS) is discussed. The FLS framework now allows an active role to be taken with respect to secondary fracture prevention despite the busy daily routine schedule. Implementation of an FLS is facilitated by dedicated instruction protocols and programs. Self-financing of an FLS is currently possible only in some specific healthcare systems. In healthcare systems in German-speaking areas a cross-financing must be available and the value of an FLS indirectly presented. Apart from the financial aspects, implementation of a FLS is also worthwhile because it can be looked on as the future driving force of innovation.

Electron transfer within a reaction path model calibrated by constrained DFT calculations: application to mixed-valence organic compounds

The quantum dynamics of electron transfer in mixed-valence organic compounds is investigated using a reaction path model calibrated by constrained density functional theory (cDFT). Constrained DFT is used to define diabatic states relevant for describing the electron transfer, to obtain equilibrium structures for each of these states and to estimate the electronic coupling between them. The harmonic analysis at the diabatic minima yields normal modes forming the dissipative bath coupled to the electronic states. In order to decrease the system-bath coupling, an effective one dimensional vibronic Hamiltonian is constructed by partitioning the modes into a linear reaction path which connects both equilibrium positions and a set of secondary vibrational modes, coupled to this reaction coordinate. Using this vibronic model Hamiltonian, dissipative quantum dynamics is carried out using Redfield theory, based on a spectral density which is determined from the cDFT results. In a first benchmark case, the model is applied to a series of mixed-valence organic compounds formed by two 1,4-dimethoxy-3-methylphenylene fragments linked by an increasing number of phenylene bridges. This allows us to examine the coherent electron transfer in extreme situations leading to a ground adiabatic state with or without a barrier and therefore to the trapping of the charge or to an easy delocalization.

CW and pulsed electrically detected magnetic resonance spectroscopy at 263GHz/12T on operating amorphous silicon solar cells

Here we describe a new high frequency/high field continuous wave and pulsed electrically detected magnetic resonance (CW EDMR and pEDMR) setup, operating at 263GHz and resonance fields between 0 and 12T. Spin dependent transport in illuminated hydrogenated amorphous silicon p-i-n solar cells at 5K and 90K was studied by in operando 263GHz CW and pEDMR alongside complementary X-band CW EDMR. Benefiting from the superior resolution at 263GHz, we were able to better resolve EDMR signals originating from spin dependent hopping and recombination processes. 5K EDMR spectra were found to be dominated by conduction and valence band tail states involved in spin dependent hopping, with additional contributions from triplet exciton states. 90K EDMR spectra could be assigned to spin pair recombination involving conduction band tail states and dangling bonds as the dominating spin dependent transport process, with additional contributions from valence band tail and triplet exciton states.