C-reactive protein in differentiation between tuberculous and malignant pleural effusions

Although several studies have investigated the levels of C-reactive protein (CRP) in various diseases states, few have focused on its role in pleural effusion. The aim of this study was to evaluate the value of pleural fluid and pleural/serum CRP in segregation between tuberculous and malignant pleural effusions. CRP was measured in both pleural fluid and serum among 2 groups of patients, the first included 15 with tuberculous effusion diagnosed by Abram's needle biopsy, while, the second incorporated 15 with malignant effusion diagnosed by either thoracoscopic or Abram's biopsy. A highly significant difference was demonstrated between pleural fluid CRP in tuberculous (29.07±9.32) and malignant (19.30±4.35) effusions. Moreover, serum CRP was significantly higher in tuberculous effusion (52.24±8.55) compared to malignant one (30.65±5.08). Furthermore, CRP pleural/serum ratio was significantly higher in malignant effusion. In conclusion, CRP is a useful and cheap marker for differentiation between tuberculous and malignant pleural effusion.