CRP and Pleural effusion: But, as we found a strong inverse relationship between HDL-c and the inflammatory serum markers as CRP, leukocyte and ESR we can elucidate that HDL maybe is not only a specific serum marker of pleural effusion (transudate or exsudate) but it is a good serum marker of the increased systemic inflammatory response of these patients and the organ-specific inflammation, in this case, the pleura.