Differential diagnostic value of sialic acid and L-fructose in pleural effusion

ABSTRACT

In order to discriminate between malignant, tuberculous pleural effusions and that due to cardiac failure,Sialic acid and L- fucose were determined in pleural fluid and serum in 44 patients; 16 with malignant, 21 with tuberculous effusion and 7 with effusion due to cardiac failure. Serum and pleural fluid levels of Sialic acid were significantly higher in malignant and tuberculous effusions than in those with effusions due to cardiac failure and insignificantly higher in malignant than in tuberculous effusions The levels of L-fucose were significantly higher in malignant effusions than in the other two types of effusion.Pleural fluid concentration of sialic acid showed the highest sensitivty and diagnostic accuracy in differentiating tuberculous effusion from that due to cardiac failure while pleural fluid concentration of L-fucose showed the highest sensitivity and diagnostic accuracy in differentiating malignant effusion from that due to cardiac failure. An obvious overlap in evaluating each of the two markers was observed on comparing malignant and tuberculous effusions. However, it was less marked on comparing either of them with that due to cardiac failure. Because serum and pleural fluid levels of the two markers were highest in malignant effusions, they seem promising in the differential diagnosis of pleural effusion in spite of the overlap with tuberculous effusion