The true frequency of PHF in dogs with pleural effusion could have been underestimated in this study due to the concurrent presence of secondary hyperfibrinolysis caused by the inflammatory disease underlying the cause of pleural effusion formation, as suggested from the significant decrease in fibrinogen/CRP ratio in the face of a higher FDPs and similar D-dimer concentrations in dogs with pleural effusions compared to control dogs. The gene discussed is CRP; the disease is Pleural effusion.