Plasma Transforming Growth Factor-β1 Level in Patients with Severe Community-acquired Pneumonia and Association with Disease Severity

Abstract

Pro- and anti-inflammatory cytokines, such as interferon (IFN)-gamma, interleukin (IL)-6, IL-10, IL-12 and transforming growth factor (TGF)-beta1, have been shown to be mediators associated with severe community-acquired pneumonia (CAP). It is unknown whether plasma TGF-beta1 level can help physicians to judge disease severity. In this study, we investigated the value of predicting mortality in patients with severe CAP by the plasma levels of IFN-gamma, IL-6, IL-10, IL-12 and TGF-beta1 on admission day. Patients who were admitted to the emergency department and soon transferred to the ICU because of severe CAP were enrolled in this study. Plasma levels of IFN-gamma, IL-6, IL-10, IL-12 and TGF-beta1 on the day of admission were determined in 49 survivors and 14 non-survivors within 28 days by ELISA. Clinical characteristics were also recorded. Plasma IL-6, IL-10 and TGF-beta1 levels on admission were significantly different between survivors and non-survivors. Conversely, there was no significant difference in plasma IFN-gamma and IL-12 levels between the survivors and non-survivors. Furthermore, the plasma TGF-beta1 level was the only independent factor associated with mortality. The value of predicting mortality in patients with severe CAP was similar for IL-6, IL-10 and TGF-beta1. Plasma IL-6 level was not related to the Acute Physiology and Chronic Health Evaluation (APACHE) II score. However, plasma IL-10 and TGF-beta1 levels were correlated with APACHE II score. A severity scoring system, including TGF-beta1 level on admission, may be considered as a useful parameter to predict outcomes of patients with severe CAP.