Role of C-C Chemokines in the Determination of Pleural Effusion Etiology

Introduction: Pleural effusion secondary to various diseases is associated with the presence of different inflammatory cells. The C-C chemokines (MCP-1 and MIP-1α), produced by pleural mesothelial cells, plays an important role in the recruitment of inflammatory cells to the pleural space. The purpose of the study was to evaluate predictive value of MCP-1 and MIP-1α in the differential diagnosis of pleural effusion. Material and methods: Based on Light’s criteria in 29 cases exudates and in 10 transudates were recognized. We investigated 39 patients with pleural effusion (congestive heart failure — 10, parapneumonic — 11, tuberculous — 6, malignant — 12). The C-C chemokines MCP-1 and MIP-1α levels in pleural effusion and serum were measured by ELISA. Results: The MCP-1 was significantly higher (p = 0.009) in the patient with exudates than in patients with transudates (2436 pg/ml and 794 pg/ml respectively). ROC curve analysis revealed however that this parameter has limited value in the differentiation of exudates an transudates (MCP-1 cut off value 1060 pg/ml, sensitivity 48%, specificity 90%, PPV 93%, NPV 37%). The chemokine MIP-1α were significantly higher (p = 0.001) in tuberculous than in the malignant effusion (405 pg/ml and 30 pg/ml respectively). Based on the ROC curve analysis, as a cut off value in the differentiation of tuberculous and malignant pleural effusion a value 120 pg/ml was accepted. The sensitivity of this test was 66% and specificity 99%, PPV 80%, NPV 84%. Conclusions: The chemokine MCP-1 has a limited value in the differentiation between transudate and exudates; MIP-1α could be helpful in the differentiation between tuberculous and malignant pleural effusion.