The many facets of immune-mediated thrombocytopenia: Principles of immunobiology and immunotherapy.

Immune thrombocytopenia (ITP) is a rare autoimmune condition, due to peripheral platelet destruction through antibody-dependent cellular phagocytosis, complement-dependent cytotoxicity, cytotoxic T lymphocyte-mediated cytotoxicity, and megakaryopoiesis alteration. This condition may be idiopathic or triggered by drugs, vaccines, infections, cancers, autoimmune disorders and systemic diseases. Recent advances in our understanding of ITP immunobiology support the idea that other forms of thrombocytopenia, for instance, occurring after immunotherapy or cellular therapies, may share a common pathophysiology with possible therapeutic implications. If a decent pipeline of old and new agents is currently deployed for classical ITP, in other more complex immune-mediated thrombocytopenic disorders, clinical management is less harmonized and would deserve further prospective investigations. Here, we seek to provide a fresh overview of pathophysiology and current therapeutical algorithms for adult patients affected by this disorder with specific insights into poorly codified scenarios, including refractory ITP and post-immunotherapy/cellular therapy immune-mediated thrombocytopenia.

Remote Photoplethysmography Is an Accurate Method to Remotely Measure Respiratory Rate: A Hospital-Based Trial.

Remote photoplethysmography imaging (rPPG) is a new solution proposed to measure vital signs, such as respiratory rate (RR) in teleconsultation, by using a webcam. The results, presented here, aim at evaluating the accuracy of such remote measurement methods, compared with existing measurement methods, in a real-life clinical setting. For each patient, measurement of RR, using the standard system (control), has been carried out concomitantly with the experimental system. A 60-s time frame was used for the measurements made by our rPPG system. Age, gender, BMI, and skin phototype were collected. We performed the intraclass correlation coefficient and Bland-Altman plot to analyze the accuracy and precision of the rPPG algorithm readings. Measurements of RR, using the two methods, have been realized on 963 patients. Comparison of the two techniques showed excellent agreement (96.0%), with most of the patients (n = 924-standard patients) being in the confidence interval of 95% in Bland-Altman plotting. There were no significant differences between standard patients and outlier patients for demographic and clinical characteristics. This study indicates a good agreement between the rPPG system and the control, thus allowing clinical use of this remote assessment of the respiratory rate.

Is There a Relationship between Hyperventilation Syndrome and History of Acute SARS-CoV-2 Infection? A Cross-Sectional Study.

Following COVID-19 infection, many patients suffer from long-lasting symptoms that may greatly impair their quality of life. Persisting dyspnea and other functional respiratory complaints can evoke hyperventilation syndrome (HVS) as a putative contributor to long-COVID presentation in COVID-19 survivors. We aimed to assess the possible relationship between HVS and previous acute COVID-19 infection. We designed a cross-sectional, single-center study, including all patients consecutively referred to our Lung Function and Exercise Testing Department between January and June 2021. Participants completed a systematic Nijmegen Questionnaire, a modified Medical Research Council dyspnea scale assessment, a post-COVID screening questionnaire, and performed a standardized lung function test. The population was divided according to HVS diagnosis, defined as a Nijmegen score of > 23/64. The occurrence of previous COVID-19 infection was compared according to the Nijmegen score after adjustment for potential confounders by multivariate logistic regression. In total, 2846 patients were included: 1472 men (51.7%) with a mean age of 56 (±16.6) years. A total of 455 patients (16%) declared a previous SARS-CoV-2 infection, and 590 patients presented a positive score (>23/64) in the Nijmegen Questionnaire (20.7%). Compared with COVID-19-free patients, there was an increased occurrence of HVS+ in cases of COVID-19 infection that did not require hospitalization (aOR = 1.93 [1.17−3.18]). The results of this large-scale, cross-sectional study suggest an association between HVS diagnosis and a history of COVID-19 disease in patients who were not hospitalized.

Accurate and Reliable Assessment of Heart Rate in Real-Life Clinical Settings Using an Imaging Photoplethysmography.

Remote photoplethysmography imaging (rPPGc) is a new method measuring essential parameters, such as heart rate (HR), which uses a video camera during teleconsultation. Our work aimed to evaluate the accuracy of such remote measurements compared with existing contact point measurement methods in real-life clinical settings. The prospective hospital-based study recruited 1045 patients who required a pulmonary function test. For each patient, measurements of HR using a standard electrocardiogram acquisition system (gold standard) were carried out concomitantly with the measurements made by the rPPGc system (Caducy v1.0.0) taken within a 60 s timeframe. Age, gender, and skin phototype were collected. We performed an intraclass coefficient correlation (ICC) and Bland-Altman plotting to determine the accuracy and precision of the rPPGc algorithm readings. We achieved measurement of HR using the two methods in 963 patients. The ICC measured at a 60 s timeframe, and when we compared the rPPGc with the gold standard, it had a 95% confidence interval (CI95) value of 0.886 [0.871:0.899]. In all, 94.6% (n = 911) patients showed promising results with a CI95 in Bland-Altman plotting. Fifty-two measurements were discordant, and further analysis established the method's accuracy at 96.2%. Our results described a good accuracy and correlation between the rPPGc system and the gold standard, thus paving the way for more precise care via telemedicine.

Real intensity of physical activity capacity of patients with chronic disease: a cross-sectional study.

The aim of this study was to evaluate the real intensity level of exercise in a sample of patients with chronic disease from obesity, rheumatology, hematology and other departments involved in a hospital-based program of adapted physical activity (APA). For this cross-sectional study, we studied seventy-five patients with chronic disease and no beta-blocker treatment. They systematically performed a cardiopulmonary exercise test before participating in a supervised APA practice using a telemetry wireless system to monitor heart rate (HR) during the first session. Based upon the results of the functional evaluation of exercise performance, we studied two groups of patients: (1) No limitation in exercise performance (maximal oxygen uptake greater than or equal to 80% of the theoretical reference) and (2) limited exercise performance (maximal oxygen uptake less than 80% of the theoretical value). Fifty-two patients (69.3%) were women, mean age was 42.6 (± 13.8), and mean BMI was 36.7 (± 10.6). Most patients had been referred for obesity (57.3%). We found 39 patients with normal exercise capacities and 36 patients with limited exercise performance. There were no significant differences in demographic and clinical characteristics between the two groups. For all populations, the mean and median real intensity levels of exercise in a sample of patients were moderate (55-70% HR max) and were the same for both groups. During the most intensive 15-min bout of the APA session, the HR for patients in both groups was greater than 70% of the actual maximum HR. This study observed a moderate level of APA exercise intensity in patients suffering from various chronic diseases. We found no significant difference in intensity level of exercise between patients' capacities, i.e., with and without limitation of their maximal performance.

Physical Activity Capacity Assessment of Patients With Chronic Disease and the 1-Minute Sit to Stand Test: Is There an Interest?

Objective: This study aimed to evaluate the efficacy of the 1-minute Sit to Stand test (1MSTS) to determine physical activity capacities for patients with chronic disease. Methods: For this cross-sectional study, we studied fifty patients with chronic disease and no beta-blocker treatment. They systematically performed a cardiopulmonary exercise test to determine maximal oxygen uptake (V'O2max). We considered two groups of patients based on the results of the functional evaluation of exercise performance: (1) No limitation in exercise performance (V'O2max greater or equal to 80% of the theoretical reference) and (2) limited exercise performance (V'O2max <80% of the theoretical value). All patients also received an 1MSTS on the same day. Results: We found 22 (44.0%) patients with normal exercise capacity and 28 (56.0%) patients with limited exercise performance. In this sample, mean 1MSTS repetitions were 27.1 (7.1) and 25.2 (8.7), respectively. There were no significant differences between the two groups for repetition and Borg Scale end test. The correlation between V'O2max measured during the exercise test and 1MSTS repetitions displayed a positive slope [r = 0.401 (95% CI 0.114-625)]. Conclusion: This study demonstrated a moderate relationship between 1MSTS and V'O2max for patients with chronic disease. 1MSTS did not permit the precise determination of physical activity capacities in this sample.

Physical Activity Capacity Assessment of Patients with Chronic Disease and the Six-Minute Walk Test: A Cross-Sectional Study.

Background: This study aimed to evaluate the efficacy of the Six-Minute Walk Test (6MWT) to determine the physical activity capacities of patients with chronic disease. Methods: For this cross-sectional study, we investigated 156 patients with chronic disease and no beta-blocker treatment. They systematically performed a maximal cardiopulmonary exercise test to determine their heart rate peak (HRPeak) and maximal oxygen uptake (V'O2max). We considered two groups of patients based upon the results of the functional evaluation of exercise performance: (1) No limitation in exercise performance (V'O2max greater or equal to 80% of the theoretical reference) and (2) limited exercise performance (V'O2max less than 80% of the theoretical value). All patients also received a 6MWT on the same day as the exercise test. Results: We found 68 (43.6%) patients with normal exercise capacities and 88 (56.4%) patients with limited exercise performance. In this sample, 6MWT mean distances were 510 (87) and 506 (86) m, respectively. There were no significant differences between the two groups for distance and end-test heart rate. The correlation between matrix V'O2max measured during the maximal incremental exercise test and the 6MWT distance displayed a positive slope (r = 0.549 CI95 [0.431−0.656]­p < 0.001). Conclusion: Our results showed a moderate relationship between 6MWT and physical activity capacity for patients with chronic disease.

Innovative measurement of routine physiological variables (heart rate, respiratory rate and oxygen saturation) using a remote photoplethysmography imaging system: a prospective comparative trial protocol.

INTRODUCTION: Physiological signals are essential for assessing human health. The absence of a medical device to carry out these measurements remotely is one of the main limitations of telemedicine. Remote photoplethysmography imaging (rPPG) makes it possible to use a camera video to measure some of the most valuable physiological variables: heart rate (HR), respiratory rate (RR) and oxygen saturation (SpO2). Our objective was to evaluate the value of such remote measurements compared with existing contact point measurements techniques in real-life clinical settings. METHODS AND ANALYSIS: Prospective hospital-based study that will recruit 1045 patients who require a pulmonary function test. For each patient, measurements of HR, RR and SpO2, using a standard acquisition system, will be carried out concomitantly with the measurements made by the rPPG system. 30, 60 and 120 s time frames will be used to take measurements. Age, gender and skin phototype will also be collected. The intraclass coefficient correlation will be performed to determine the accuracy and precision of the rPPG algorithm readings. ETHICS AND DISSEMINATION: The study protocol has been approved by the French Agency for the Safety of Health Products (ANSM registration no. ID RCB 2020-A02428-31) and by a French ethics committee (CPP OUEST I-TOURS-2020T1-30 DM at 30 October 2020). Results will be published in peer-reviewed journals, at scientific conferences and through press releases. TRIAL REGISTRATION NUMBER: NCT04660318.

Global prevalence of spondyloarthritis in low-income and middle-income countries: a systematic review and meta-analysis protocol.

INTRODUCTION: In the past decade, the definition of spondyloarthritis (SpA) has undergone major modifications with respect to new diagnostic tools and classifications. With the advent of biotherapies, treatment possibilities in patients with SpA have substantially improved in the last few years. There is great interest in obtaining accurate data on the disease prevalence, especially in regions where data remains scarce such as low-income and middle-income countries (LMICs), in order to measure and understand the needs of their healthcare systems. Therefore, through a global systematic review and meta-analysis, the current study aims to investigate the prevalence of SpA and human leucocyte antigen B27 (HLAB27) and its association with the risk of SpA in the LMIC population. METHODS AND ANALYSIS: We will include cohort, case-control and cross-sectional studies performed among adults (>15 years) living in LMICs. EMBASE, Medline, Global Index Medicus and Web of Knowledge will be searched for relevant records published until 30 April 2020, without any language restriction. The review will be reported according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. After screening of titles and abstracts, study selection, data extraction and risk of bias assessment by two independent reviewers, we shall assess the studies individually for clinical and statistical heterogeneity. Random-effect meta-analysis will be used to pool studies judged to be clinically homogeneous. Egger's test and visual inspection of funnel plots will be used to assess publication bias. Results will be presented by WHO subregions. ETHICS AND DISSEMINATION: Since primary data is not collected in this study, ethical approval is not required. This review is expected to provide relevant data on the epidemiology of SpA, HLAB27 and their association in the global population of LMICs. The final report will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42020163898.