Background: In the postacute phase of coronavirus disease-2019 (COVID-19), survivors may have persistent symptoms, lung function abnormalities, and sequelae lesions on thoracic computed tomography (CT). This new entity has been defined as post-COVID interstitial lung disease (ILD) or residual disease. Aims: To evaluate the characteristics, risk factors and clinical significance of post-COVID ILD. Study Design: Multicenter cross-sectional analysis of data from a randomized clinical study. Methods: In this study, patients with persistent respiratory symptoms 3 months after recovery from COVID-19 were evaluated by two pulmonologists and a radiologist. post-COVID ILD was defined as the presence of respiratory symptoms, hypoxemia, restrictive defect on lung function tests, and interstitial changes on follow-up high-resolution computed tomography (HRCT). Results: At the three-month follow-up, 375 patients with post-COVID-19 syndrome were evaluated, and 262 patients were found to have postCOVID ILD. The most prevalent complaints were dyspnea (n = 238, 90.8%), exercise intolerance (n = 166, 63.4%), fatigue (n = 142, 54.2%), and cough (n = 136, 52%). The mean Medical Research Council dyspnea score was 2.1 +/- 0.9, oxygen saturation was 92.2 +/- 5.9%, and 6-minute walking distance was 360 +/- 140 meters. The mean diffusing capacity of the lung for carbon monoxide was 58 +/- 21, and the forced vital capacity was 70% +/- 19%. Ground glass opacities and fibrotic bands were the most common findings on thoracic HRCT. Fibrosis-like lesions such as interlobular septal thickening and traction bronchiectasis were observed in 38.3% and 27.9% of the patients, respectively. No honeycomb cysts were observed. Active smoking [odds ratio (OR), 1.96; 95% confidence interval (CI), 1.44-2.67), intensive care unit admission during the acute phase (OR, 1.46; 95% CI, 1.1-1.95), need for high-flow nasal oxygen (OR, 1.55; 95% CI, 1.42-1.9) or non-invasive ventilation (OR, 1.31; 95% CI, 0.8-2.07), and elevated serum lactate dehydrogenase levels (OR, 1.23; 95% CI 1.18-1.28) were associated with the development of post-COVID ILD. At the 6-month follow-up, the respiratory symptoms and pulmonary functions had improved spontaneously without any specific treatment in 35 patients (13.4%). The radiological interstitial lesions had spontaneously regressed in 54 patients (20.6%). Conclusion: The co-existence of respiratory symptoms, radiological parenchymal lesions, and pulmonary functional abnormalities which suggest a restrictive ventilatory defect should be defined as post-COVID-19 ILD. However, the term "fibrosis" should be used carefully. Active smoking, severe COVID-19, and elevated lactate dehydrogenase level are the main risk factors of this condition. These post-COVID functional and radiological changes could disappear over time in 20% of the patients.

Background/Objectives: This study investigated the frequency of syncope, factors associated with syncope, and the relationship between syncope and mortality in patients with pulmonary thromboembolism (PTE). Methods: This study was planned as single-center retrospective and cross-sectional research. The PTE diagnosis was confirmed by partial or complete filling defects in at least one branch of the pulmonary circulation seen on pulmonary spiral computed tomography angiography. Patients’ demographic data, symptoms, location of pulmonary embolism, Simplified Pulmonary Embolism Severity Index (sPESI) risk group, European Society of Cardiology (ESC) risk group, in-hospital mortality rate, and 30-day mortality rate were recorded. The presence of syncope and associated factors as well as the relationship between syncope and mortality were investigated. Results: This study included 589 consecutive patients diagnosed with PTE. The mean age was 70 ± 15 years, and 58.7% of the patients were women. Syncope was detected in 12.4% of the patients. Female sex, pulse rate, thrombosis in the main pulmonary artery, and right ventricular dysfunction on an echocardiogram were more prevalent in the syncope group. In-hospital mortality was 2.1 times higher in the syncope group. Elevated troponin levels increased the occurrence of syncope by 4.9-fold, whereas the presence of thrombosis in the main pulmonary artery and signs of right ventricular failure increased syncope occurrence by 4.3- and 3.1-fold, respectively. Conclusions: In the presence of syncope, patients with pulmonary thromboembolism, embolism in the main pulmonary arteries, high troponin values, right heart failure, and a high sPESI risk group should be carefully assessed and closely monitored for mortality, and reperfusion therapy should be considered as necessary.

Obstructive sleep apnea (OSA) is a common sleep-related disorder associated with cardiovascular and metabolic comorbidities. Early diagnosis is essential; however, access to polysomnography is limited. Machine learning approaches may support clinical decision-making by predicting OSA using easily obtainable variables. This study aimed to develop an artificial neural network (ANN) model to predict the presence and severity of OSA. This multicenter study included adult patients who underwent diagnostic polysomnography at ten different sleep centers. Eighteen demographic and clinical parameters were used as input features, and four OSA severity categories served as output classes. The ANN architecture consisted of one hidden layer with 50 neurons (ReLU activation) and a Softmax output layer. The dataset was randomly divided into training (80%) and testing (20%) sets. A total of 1,954 participants (70.2% male) were included. Polysomnography classified 39.2% of participants as severe OSA, 29.4% as mild OSA, 15.0% as moderate OSA, and 16.4% as non-OSA. The ANN model demonstrated good discriminative performance across OSA severity categories, with class-specific AUC values ranging from 0.89 to 0.96. These findings support the potential utility of ML-based tools for screening and early risk stratification, particularly in resource-limited settings.

Pnömoni klinik olarak; balgamlı öksürük, pürülan balgam, dispne ve/veya takipne, akciğer grafisinde infiltrasyonlarla birlikte olan plöritik göğüs ağrısı semptom ve bulgularından iki veya daha fazlasının olmasıdır. İmmun yetmezlik; organizmanın immun sistemde zayıflama ya da yetmezlik nedeniyle, enfeksiyon ajanlarına karşı beklenen yanıtı verememesi durumudur. Akciğerler immün yetmezlik hastalıklarında etkilenen doku ve organların başında gelmektedir, efektif tedavi edilemediği durumlarda komplike olabilmektedir. Bu sebeple immun yetmezlik zemininde gelişen pnömöni olgusunu, toplum kökenli pnömöniden ayırt etmek ve tedavinin erken başlanması olası komplikasyonları önlemek açısından oldukça önemlidir.

Background: Differentiating exudative from transudative pleural effusions is essential for accurate diagnosis and management. Although Light’s criteria remain the standard diagnostic method, they may incorrectly classify a substantial proportion of transudative effusions as exudates. This study aimed to evaluate the diagnostic performance of pleural fluid cholesterol and compare it with Light’s criteria. Methods: This retrospective study included 751 patients with pleural effusion who underwent diagnostic evaluation between 2015 and 2024 and had a definitive etiological diagnosis. All patients underwent ultrasound-guided thoracentesis with simultaneous pleural fluid and serum biochemical analyses. Based on final etiological diagnosis, effusions were classified as transudative or exudative. Results: The mean age was 68.6 ± 15.8 years. Of the pleural effusions, 516 (68.7%) were exudative and 235 (31.3%) were transudative. Malignant pleural effusion was the most common cause of exudates, whereas congestive heart failure predominated among transudates. Pleural fluid cholesterol levels were significantly higher in exudative than transudative effusions (91.1 ± 30.7 vs. 28.9 ± 13.5 mg/dL, p < 0.001). Receiver operating characteristic (ROC) analysis demonstrated excellent diagnostic performance for pleural fluid cholesterol (AUC = 0.976, 95% CI 0.965–0.987, p < 0.001). A pleural cholesterol cut-off value of ≥50 mg/dL demonstrated 92.2% sensitivity, 94.9% specificity, 97.5% positive predictive value, and 84.8% negative predictive value for identifying exudative effusions. Light’s criteria showed higher sensitivity (99.2%) but lower specificity (84.4%). Light’s criteria misclassified 15.6% of transudative effusions as exudates, whereas pleural cholesterol misclassified only 5.1%. Conclusions: Pleural fluid cholesterol measurement demonstrated high diagnostic accuracy in differentiating exudative and transudative pleural effusions and substantially reduced false exudate classification compared with Light’s criteria. Routine assessment of pleural cholesterol may improve the diagnostic evaluation of pleural effusions.