Chronic active hepatitis in dogs associated with leptospires

Area of Science:

• Veterinary Medicine
• Infectious Diseases
• Hepatology

Background:

• Chronic active hepatitis is a serious liver condition in dogs.
• Leptospirosis is a bacterial disease caused by Leptospira interrogans, affecting various mammals.
• The specific association between Leptospira interrogans serovar grippotyphosa and chronic active hepatitis in dogs has not been previously reported.

Purpose of the Study:

• To investigate the potential role of Leptospira interrogans serovar grippotyphosa in chronic active hepatitis in American Foxhounds.
• To determine the prevalence of grippotyphosa exposure in a kennel with affected dogs.

Main Methods:

• Diagnosis of chronic active hepatitis in affected dogs.
• Microscopic examination of liver tissues for spirochetes.
• Serological testing for Leptospira interrogans serovar grippotyphosa antibodies.
• Kennel-wide serologic survey to assess exposure rates.

Main Results:

• Five American Foxhounds were diagnosed with chronic active hepatitis.
• Spirochetes were identified in the liver tissues of four affected dogs.
• The fifth dog showed a rising titer to Leptospira interrogans serovar grippotyphosa, though spirochetes were not found in its tissues.
• Serological evidence of grippotyphosa exposure was found in 6 out of 13 dogs in the kennel.

Conclusions:

• This study suggests a possible association between Leptospira interrogans serovar grippotyphosa infection and chronic active hepatitis in American Foxhounds.
• Leptospiral infection should be considered in the differential diagnosis of chronic active hepatitis in dogs, particularly in endemic areas.
• Further research is warranted to elucidate the pathogenic mechanisms linking grippotyphosa and canine hepatitis.