[Experimental model of Lyme disease in rats].

BACKGROUND

An experimental model in rats can contribute to the understanding of the pathogenesis and improvement of treatment of Lyme borreliosis.

OBJECTIVE

To develop a Lyme arthritis experimental model in Sprague-Davies rats.

MATERIAL AND

METHODS

An intraperitoneal inoculation of Borrelia burgdorferi in three groups of Sprague-Davies rats was made. The first group was inoculated with dead B. burgdorferi. The second group was inoculated with low virulence B-31 B. burgdorferi. The third group was inoculated with high virulence B-297 B. burgdorferi.

RESULTS

After six months of follow-up, none of the rats in the first two groups presented arthritis whereas in the third group 18 rats (72%) developed arthritis in one or more joints. Histologic showed synovial hypertrophy and inflammatory infiltration composed of polymorphonuclear leukocytes, plasma and mast cells in the infected joint. B. burgdorferi was isolated in the liver and spleen cultures taken 14 days after inoculation in 40% of the rats inoculated with B-297 strain.

CONCLUSION

An easy and inexpensive experimental model of Lyme arthritis in rats has been developed.