Background: Aspiration of stomach content or saliva in critical conditions—e.g., shock, intoxication, or resuscitation—can lead to acute lung injury. While various biomarkers in bronchoalveolar lavage fluids have been studied for diagnosing aspiration, none have been conclusively established as early indicators of lung damage. This study aims to evaluate the diagnostic value of pepsin, bile acid, and other biomarkers for detecting aspiration in an intensive care unit (ICU). Materials and methods: In this study, 50 ICU patients were enrolled and underwent intubation before admission. The evaluation of aspiration was based on clinical suspicion or documented instances of observed events. Tracheal secretion (TS) samples were collected within 6 h after intubation using sterile suction catheters. Additional parameters, including IL-6, pepsin, and bile acid, were determined for analysis. Pepsin levels were measured with an ELISA kit, while bile acid, uric acid, glucose, IL-6, and pH value in the tracheal secretion were analyzed using standardized lab methods. Results: The 50 patients admitted to the ICU with various diagnoses. The median survival time for the entire cohort was 52 days, and there was no significant difference in survival between patients with aspiration pneumonia (AP) and those with other diagnoses (p = 0.69). Among the AP group, the average survival time was 50.51 days (±8.1 SD; 95% CI 34.63–66.39), while patients with other diagnoses had a mean survival time of 32.86 days (±5.1 SD; 95% CI 22.9–42.81); the survival group comparison did not yield statistically significant results. The presence of pepsin or bile acid in TS patients did not significantly impact survival or the diagnosis of aspiration. The p-values for the correlations between pepsin and bile acid with the aspiration diagnosis were p = 0.53 and p > 0.99, respectively; thus, pepsin and bile acid measurements did not significantly affect survival outcomes or enhance the accuracy of diagnosing aspiration pneumonia. Conclusions: The early and accurate diagnosis of aspiration is crucial for optimal patient care. However, based on this study, pepsin concentration alone may not reliably indicate aspiration, and bile acid levels also show limited association with the diagnosis. Further validation studies are needed to assess the clinical usefulness and reliability of gastric biomarkers in diagnosing aspiration-related conditions. Such future studies would provide valuable insights for improving aspiration diagnosis and enhancing patient care.

Background: Lung transplantation (LTx) is a life-saving intervention for patients with advanced interstitial lung disease (ILD), markedly improving pulmonary function, exercise capacity, and right heart function, yet it is often accompanied by increased risks of metabolic, cardiovascular, and renal complications. Methods: We conducted a longitudinal analysis of 102 ILD patients post-LTx, integrating pulmonary, cardiovascular, metabolic, and functional parameters. Recovery was assessed using lung function parameters (FVC, DLCO, TLC, ITGV, and FEV1), 6MWD, Borg scores, sPAP, TAPSE, BMI, and weight, while the comorbidity burden was monitored via the Comorbidity–Polypharmacy Score (CPS). Results: Patients showed marked post-LTx improvements, with FVC and DLCO increasing by +37.99% and +42.90%, 6MWD by +166.5 m, and dyspnea decreasing by −3.25 points (Borg scale). Right heart function improved (sPAP −23.79 mmHg and TAPSE increased). Despite these gains, renal function (eGFR −14.14 mL/min/1.73 m²/year) and platelet counts (−17.79 × 10⁹/L/year) declined, while the CPS nearly doubled (16 to 30), reflecting rising comorbidities, including hypertension, diabetes, osteoporosis, reflux, and malignancies. Conclusions: While LTx significantly enhances pulmonary function, exercise capacity, and hemodynamics in ILD patients, it also triggers complex systemic adaptations and a rising comorbidity burden, underscoring the need for dynamic risk stratification and integrated care to balance the benefits and burden over time.

Background: Chronic lung allograft dysfunction (CLAD) occurs in up to 50% of patients within the first five years after lung transplantation (LuTX) and represents the main complication and cause of death regarding this surgery. Alveolar septal widening in transbronchial biopsies has shown an association with acute humoral allograft rejection. We aimed to explore histological markers that could predict the development of CLAD before its clinical manifestation. Methods: We retrospectively analyzed transbronchial biopsies taken at three time points from 57 patients who underwent LuTX between February 2010 and July 2019, 26 of whom developed CLAD up to November 2022. The biopsies were analyzed by microscopic morphometry and quantitative reverse transcription PCR to identify predictors of CLAD. Results: CLAD development was associated with increased alveolar septal width (ASW) as early as the first year post-LuTX (5.46 ± 0.76 µm versus 4.59 ± 0.44 µm; p < 0.001). The ASW in later biopsy timepoints predicted survival in multivariate models (last timepoint: hazard ratio 1.885, 95% confidence interval 1.086–3.269). Collagen (COL1A1 and COL3A1) expression was significantly increased in samples from patients who developed CLAD compared with those who did not. The increase in ASW was paralleled by interstitial deposition of COL1A1 and COL3A1 and a decrease in both the carbon monoxide (DLCO) diffusing capacity of the lung and the DLCO/alveolar volume. Conclusions: We report a new histologic approach for early assessment of risk of CLAD in patients who have undergone LuTX. The ASW represents a pre-symptomatic, continuous, and widely distributed change within the lung parenchyma that is accessible to transbronchial biopsy.