In a recent publication, Dr. Rühl-Fehlert and colleagues described infections of beagle dogs with different serotypes of leptospira, namely serovar saxkoebing and serovar sejroe. Besides using serology and bacteriology, the authors investigated the dogs in their study by clinical observation and clinical chemistry and described the macroscopic and histopathological findings in detail. While the dogs infected by the first type remained essentially healthy and showed at the most mild interstitial nephritis, the second serotype occasionally led to acute and severe illness and within days to death. In the discussion of their paper, the authors provide a good overview over leptospirosis infection in dogs, as relevant for the toxicologic pathologist. In particular they point out that latent leptospira infection is not detected by routine clinical parameters, e.g. during the quarantine phase, and infected dogs may thus enter toxicity studies. Clinically healthy carriers may spread the infection to new dogs. Therefore, random checking of leptospira titres may be advisable and should in fact already be performed by the breeder. Man might also be at risk when exposed to leptospira-infected dogs and the authors recommend that animal caretakers protect themselves appropriately. Attention must also be paid to disinfection of animal rooms and equipment used in these rooms. An optimal prevention can only be achieved by a stock- or population-specific vaccine, which is not commercially available, but can be produced in specialized institutions.

With this competent and comprehensive publication Dr. Rühl-Fehlert and her colleagues have made a valuable contribution to toxicologic pathology in general and to a safe and reproducible use of dogs in toxicity studies.

Reference:
Rühl-Fehlert CI, Brem S, Feller W, Kopp H, Meyer P, Rinke M (2000) Clinical, microbiological and pathological observations in laboratory beagle dogs infected with leptospires of the serogroup Sejroe. Exp Toxicol Pathol 52: 201-207

Munich, September 7, 2001