Texture Analysis in the Evaluation of COVID-19 Pneumonia in Chest X-Ray Images: A Proof of Concept Study.

BACKGROUND: One of the most challenging aspects related to Covid-19 is to establish the presence of infection in an early phase of the disease. Texture analysis might be an additional tool for the evaluation of Chest X-ray in patients with clinical suspicion of Covid-19 related pneumonia. OBJECTIVE: To evaluate the diagnostic performance of texture analysis and machine learning models for the diagnosis of Covid-19 interstitial pneumonia in Chest X-ray images. METHODS: Chest X-ray images were accessed from a publicly available repository(https://www.kaggle. com/tawsifurrahman/covid19-radiography-database). Lung areas were manually segmented using a polygonal region of interest covering both lung areas, using MaZda, a freely available software for texture analysis. A total of 308 features per ROI was extracted. One hundred-ten Covid-19 Chest X-ray images were selected for the final analysis. RESULTS: Six models, namely NB, GLM, DL, GBT, ANN, and PLS-DA were selected and ensembled. According to Youden's index, the Covid-19 Ensemble Machine Learning Score showing the highest area under the curve (0.971±0.015) was 132.57. Assuming this cut-off the Ensemble model performance was estimated by evaluating both true and false positive/negative, resulting in 91.8% accuracy with 93% sensitivity and 90% specificity. Moving the cut-off value to -100, although the accuracy resulted lower (90.6%), the Ensemble Machine Learning showed 100% sensitivity, with 80% specificity. CONCLUSION: Texture analysis of Chest X-ray images and machine learning algorithms may help in differentiating patients with Covid-19 pneumonia. Despite several limitations, this study can lay the ground for future research works in this field and help to develop more rapid and accurate screening tools for these patients.

Obstructive sleep apnea in sarcoidosis and impact of cpap treatment on fatigue.

RATIONALE: An increased incidence of Obstructive Sleep Apnea (OSA) in sarcoidosis has been described in small sample size studies. Fatigue is common in sarcoidosis and OSA could be a relevant, treatable comorbidity. To date, the effect of Continuous Positive Airway Pressure (CPAP) on fatigue has never been assessed. OBJECTIVES: To investigate the prevalence of OSA in sarcoidosis, fatigue status and daytime sleepiness in patients of our center. To explore the effect of CPAP in fatigue and daytime sleepiness after 3 months using validated questionnaires. METHOD: Single group, one center, open-label prospective cohort study. MEASUREMENTS AND MAIN RESULT: We enrolled 68 patients and OSA was diagnosed in 60 (88.2%): 25 (36.8%) were mild while 35 (51.5%) were moderate-to-severe. 38 (55.9%) patients received CPAP but only 20 (30.9%) were compliant at 3-month evaluation. Questionnaires demonstrated fatigue in 34 (50%) and daytime sleepiness in 21 (30.9%). In multivariate regression analysis, Scadding stage and FAS behave as predictors of Apnea-Hypopnea Index (AHI) severity while sleepiness and steroids weren't associated. FAS score (ΔFAS = 6.3; p = 0.001) and ESS score (ΔESS = 2.8; p = 0.005) improved after three months of CPAP. CONCLUSIONS: OSA is highly prevalent in patients affected by sarcoidosis. ESS questionnaire is not reliable for OSA screening and other pre-test probability tool should be evaluated in further studies. CPAP leads to a significative reduction of fatigue and daytime sleepiness at three-month. Further studies are needed to confirm the high prevalence of OSA in sarcoidosis and the positive role of CPAP in fatigue. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (2): 169-178).

Alemtuzumab-induced lung injury in multiple sclerosis: Learning from adversity in three patients.

BACKGROUND: Respiratory alemtuzumab-related adverse events are clinically heterogeneous and include respiratory infections, infusion-related dyspnea, hypoxia and secondary autoimmune disorders. CASE REPORT: Here we report three cases of drug-induced lung disease following treatment with alemtuzumab in multiple sclerosis patients. First case was diagnosed as a non-specified intestitial pneumonitis associated with organizing pneumonia with subacute onset, second case was an acute respiratory distress syndrome with onset during second cycle, third case was a diffuse acute alveolar hemorrhage during first cycle infusion. All patients developed acute respiratory failure, reversible after steroid therapy. CONCLUSIONS: Clinicians should be aware to early recognize acute and subacute respiratory adverse events for a promptly management. In these patients re-treatment is challenging.

Investigational drugs for idiopathic pulmonary fibrosis.

INTRODUCTION: IPF is a specific form of chronic fibrosing interstitial pneumonia of unknown cause, characterized by progressive worsening in lung function and an unfavorable prognosis. Current concepts on IPF pathogenesis are based on a dysregulated wound healing response, leading to an over production of extracellular matrix. Based on recent research however, several other mechanisms are now proposed as potential targets for novel therapeutic strategies. Areas covered: This review analyzes the current investigational strategies targeting extracellular matrix deposition, tyrosine-kinase antagonism, immune and autoimmune response, and cell-based therapy. A description of the pathogenic rationale implied in each novel therapeutic approach is summarized. Expert opinion: New IPF drugs are being evaluated in the context of phase 1 and 2 clinical trials. Nevertheless, many drugs that have shown efficacy in preclinical studies, failed to exhibit the same positive effect when translated to humans. A possible explanation for these failures might be related to the known limitations of animal models of the disease. The recent development of 3D systems composed of cells from individual patients that recreate an ex-vivo model of IPF, could lead to significant improvements in disease pathogenesis and treatment. New drugs could be tested on more genuine models and clinicians could tailor therapy based on patient's response.

New treatment directions for IPF: current status of ongoing and upcoming clinical trials.

INTRODUCTION: The main objective of this review is to explore the wide and expanding field of new clinical trials in IPF. Recent trials have confirmed the efficacy of the approved drugs pirfenidone and nintedanib; nonetheless, the discovery of new biological pathways has opened new horizons in this field. Areas covered: New strategies against matrix deposition are under study and so is for the role of immunity and autoimmunity. Recent advances in the use of stem cells are opening new possibilities for the recovery of damaged lung tissues. The role of microbioma is under investigation in order to evaluate the use of antibiotics in IPF treatment. Analysing all the new and the upcoming clinical trials, we are trying to offer a comprehensive view of the emerging new frontiers in the treatment of IPF. Expert commentary: The key points for the ongoing and upcoming clinical trials will be to avoid previous mistakes and to choose carefully both study populations and efficacy endpoints. The exciting possibility to enrol patients with progressive lung fibrosis, both idiopathic and not, could be a next step forward. How the existing therapies will fit in a futurist scenario of personalized medicine is still a challenge.