CORYNEBACTERIUM-PARVUM VERSES TETRACYCLINE AS PLEURAL SCLEROSING AGENTS IN RABBITS

Tetracycline has been one of the most commonly used agents for produci ng a pleurodesis. However, it is no longer available due to more strin gent requirements on the manufacturing process. The objective of this project was to determine whether Cornyebacterium parvum is an effectiv e sclerosant in an experimental model in rabbits. The following medica tions were instilled intrapleurally in anaesthetized male rabbits: tet racycline 35 mg . kg(-1) or C. parvum 4 or 8 mg, all diluted with bact eriostatic saline solution. Twenty eight days after the instillation, the animals were sacrificed and the pleural spaces assessed macroscopi cally for evidence of pleurodesis and microscopically for evidence of fibrosis and inflammation. The intrapleural injection of C. parvum was ineffective in creating pleural fibrosis. The mean degree of pleurode sis in the 10 rabbits who received tetracycline was 3.5+/-0.7 (scale 0 -4) whilst in the 10 rabbits that received 4 mg C. parvum it was 0.0+/ -0.0, and in the 10 rabbits that received 8 mg C. parvum it was 0.5+/- 0.8. Based on this study, we recommend that C. parvum should not be us ed as a pleural sclerosant in patients with normal pleura.