Cardiac involvement in European canine babesiosis - a pathological perspective.

Canine babesiosis is an important and potentially life-threatening disease of worldwide significance. European babesiosis encompasses all protozoan parasites of the genus Babesia that have been reported to cause canine disease in Europe. Despite its importance, cardiac pathology associated with European babesiosis remains poorly characterized. The aim of this study was to assess cardiac lesions in dogs that succumbed to European babesiosis. For this study, the archive of the Department of Veterinary Pathology, Faculty of Veterinary Medicine Zagreb, was retrospectively searched for necropsied dogs which died as a consequence of naturally acquired European babesiosis. Babesiosis was diagnosed by detection of trophozoites within erythrocytes, but not lymphocytes, in cytological and/or histological slides. Necropsy reports, photographs of cardiac gross lesions, and histologic slides of the heart were reviewed, and all changes were noted. The most common gross pathologies were hemorrhage and pericardial effusion, while intravascular monocytic leukostasis, hemorrhage, endomysial edema, myocardial necrosis, congestion, and myocarditis were the most frequent histologic findings. Based on results of the current study, cardiac lesions in clinical cases of complicated European babesiosis should be expected and patients should be evaluated for such damage.