Diffusion veineuse et capillaire de enterococcus faecalis lors de bactériémies expérimentales chez le poulet

Abstract

Capillary and venous diffusion of bacteria were studied in chickens after intravenous inoculation with a strain of Enterococcus faecais isolated from a case of septicaemia in a human neonate.

One group of 13 chickens was inoculated with 10⁸ bacteria/animal and another group of 20 chickens with 10⁷ bacteria/animal. The level of bacteraemia in the first group of chickens was similar in capillary and venous blood. With 10⁸E. faecalis, the clearance of bacteria was very weak. The level of bacteraemia in the second group was significantly higher (after 180 min) in capillary than in venous blood, which suggests slower bacterial clearance in capillary than in venous blood. However, clearance was more efficient with the inoculum of 10⁷E. faecalis than with the first type of inoculum.

These experimental data confirm the greated sensitivity of capillary rather than venous sampling, which we have already observed in chickens, under similar experimental conditions, with Escherichia coli K12. Persistance of bacteria in the capillaries could account for the higher level of sensitivity of capillary microblood culture than venous blood culture, which is in agreement with the capillary trapping hypothesis of Knudson and Alden.