P8-13 Changes of laboratory findings in two dogs infected with Brucella canis following antibiotic treatment and orchiectomy: a case report

Abstract

Canine brucellosis caused by Brucella canis (B. canis) is an emerging infection affecting dogs worldwide and potentially transmissible to humans. The disease is frequently observed in stray dogs or in breeding kennels where is responsible for important economic losses. Disease control measures consider treatment or euthanasia of infected animals, as no vaccines are available. Use of antibiotics is not encouraged due to the uncertain success of the cure and the high risk of disease relapse. Still this represents the only alternative to euthanasia, usually combined to orchiectomy and ovary-hysterectomy to reduce the risk of disease transmission. Data on the combined effect of castration and antibiotic treatments of B. canis infected dogs are limited and very often follow up information are missing. The aim of the study was to describe from a diagnostic laboratory perspective the effect of antibiotic therapy and castration on male infected dogs. Twomale dogs of 8 months and 6 years old were identified as B. canis infected during trace back activities related to the B. canis outbreak occurred in Italy in 2020. One animal derived from the infected breeding kennel (patient 1) and was showing cryptorchidism while the second animal (patient 2) was exposed to direct contact with the infected dog, sharing the same environment. Laboratory investigations for B. canis were carried out before and after antibiotic treatment and orchiectomy, on sera, EDTA blood, urine and testicles. Animals were treated with two different therapeutic protocols. Before treatment, both animals showed high level of antibodies to microplate agglutination test and B. canis was also isolated from blood and urine. One month after antibiotic treatment, we observed a decrease of antibody titers and just for patient 1, B. canis was detected only by PCR from blood and urine. Orchiectomy was executed after one moths of antibiotic therapy and and no bacteria were detected in the testicles. Animal tested negative to both serology and bacteriology at follow up analyses carried out 1 year later. Despite the encouraging results, periodic follow up remain mandatory to exclude possible relapses of infection. Data also demonstrated that antimicrobial treatment influences laboratory test outcome.