Local beneficial effect of coumarin in experimental peritonitis.

Coumarin, a potent immune stimulant and macrophage activator, has been used to treat brucellosis and as an immune suppressor. The effect of Coumarin and systemic antibiotics on septicaemia, survival and peritoneal contamination in experimental peritonitis was assessed. Four groups of male Sprague-Dawley rats were inoculated with Clostridium perfringens, Escherichia coli and Bacteroides fragilis. Group A received saline alone, Group B received Coumarin alone, Group C received antibiotics (Clindamycin and Cephradine) alone and Group D received both Coumarin and antibiotics. Septicaemia, confirmed by blood culture, occurred in all animals. Coumarin did not improve survival whether given alone or in combination with antibiotics. Animals given Coumarin (Groups B and D) had significantly less peritoneal soiling (54%, 0%) (P less than 0.02, P less than 0.001) than their controls (Groups A and C: 92%; 29%). While Coumarin did not improve resistance to septicaemia it did exert a local beneficial effect.