Angiogenic factors and angiogenesis inhibitors in exudative pleural effusions.

The angiogenesis system has been implicated in inflammatory and neoplastic processes; nevertheless, it has been little studied in relation to the pleural space. Our aim is to analyze pleural and plasma levels of the activators--vascular endothelial growth factor, basic fibroblastic growth factor, and inhibitors--endostatin and thrombospondin-1 and to estimate the association between these factors and related biochemical markers. We analyzed pleural fluid from 105 patients with one of the following types of pleural effusion: empyema or complicated parapneumonic, non-complicated parapneumonic, tuberculous, neoplastic and transudative. Angiogenesis activators were higher in exudates than in transudates (p < 0.001) and in empyema than in non-complicated parapneumonic patients (p < 0.001). Endostatin showed no significant differences. Trombospondin-1 showed higher levels in exudates than in transudates and in empyema than in non-complicated parapneumonic effusions (p < 0.001). In pleural exudates there was a positive correlation of angiogenesis activators and trombospondin-1 with low glucose and pH and high LDH. There was no correlation between pleural and plasma levels of the angiogenesis factors. We conclude that exudative pleural effusions showed higher vascular endothelial growth factor, basic-fibroblastic growth factor and trombospondin-1 values than transudative effusions that associated to low glucose and pH, and high LDH. There was no correlation between pleural and plasma concentrations, suggesting a compartmentalized response.

Accuracy of chest sonography and polymorphonuclear elastase in the assessment of bacterial pleural effusion.

Background: The relationship between chest sonography findings and inflammatory markers for assessing bacterial pleural effusion is not well established. We decided to study the accuracy of chest sonography in determining the nature of bacterial pleural effusion and its relationship with polymorphonuclear elastase (PMN-E) results. Methods: Pleural sonography and PMN-E were evaluated in a prospective study of 144 consecutive patients with pleural effusion of various etiologies: 25 complicated parapneumonic, 18 uncomplicated parapneumonic, 33 tuberculous, 17 malignant, 12 transudates, and 39 of unknown etiology. The sonographer distinguished between anechoic and septated pattern. The relationship between sonographic appearance and inflammatory markers was evaluated. Results: All of the complicated parapneumonic, 11 uncomplicated parapneumonic, and 28 tuberculous effusions were septated. Septated pattern and PMN-E value were independent predictors of infectious pleural disease (p <0.05). The simultaneous presence of a septated pattern and a PMN-E higher than 100 microg/l had a sensitivity of 79.1% and a specificity of 91.1% for the diagnosis of bacterial effusions. Conclusions: PMN-E level and the sonographic pattern of pleural fluid may be useful in the diagnosis of bacterial pleural effusions.