Diagnosis of parapneumonic pleural effusion with serum and pleural fluid Activin A

Abstract Objective The aim is to evaluate the diagnostic value of Activin A levels in serum and pleural fluid on Parapneumonic Pleural Effusion (PPE). Methods The authors collected serum and pleural fluid from 86 PPE and 37 Non-PPE (NPPE) patients. Including Activin A, levels of biomarkers such as Lactate Dehydrogenase (LDH), Procalcitonin (PCT), and C-Reactive Protein (CRP) were measured. All factors were calculated for association with days after admission. The diagnostic potential of biomarkers on PPE was considered by Receiver Operating Characteristic (ROC) curve analysis. Results Levels of Activin A in serum and pleural fluid of PPE patients were significantly higher than those of the NPPE patients. Moreover, concentrations of Activin A in pleural fluid showed a more obvious relevant days after admission. ROC curve analysis found that Activin A in pleural fluid had AUCs of 0.899 with 93% sensitivity and 84% specificity for PPE diagnosis. Conclusion Activin A in pleural fluid correlated with disease severity could act to diagnose PPE.

Elevated serum Activin A in chronic obstructive pulmonary disease with skeletal muscle wasting

OBJECTIVE: Muscle wasting contributes to the reduced quality of life and increased mortality in chronic obstructive pulmonary disease (COPD). Muscle atrophy in mice with cachexia was caused by Activin A binding to ActRIIB. The role of circulating Activin A leading to muscle atrophy in COPD remains elusive. METHODS: In the present study, we evaluated the relationship between serum levels of Activin A and skeletal muscle wasting in COPD patients. The expression levels of serum Activin A were measured in 78 stable COPD patients and in 60 healthy controls via ELISA, which was also used to determine the expression of circulating TNF-α levels. Total skeletal muscle mass (SMM) was calculated according to a validated formula by age and anthropometric measurements. The fat-free mass index (FFMI) was determined as the fat-free mass (FFM) corrected for body surface area. RESULTS: Compared to the healthy controls, COPD patients had upregulated Activin A expression. The elevated levels of Activin A were correlated with TNF-α expression, while total SMM and FFMI were significantly decreased in COPD patients. Furthermore, serum Activin A expression in COPD patients was negatively associated with both FFMI and BMI. CONCLUSION: The above results showed an association between increased circulating Activin A in COPD patients and the presence of muscle atrophy. Given our previous knowledge, we speculate that Activin A contributes to skeletal muscle wasting in COPD.