Evaluation of Hematological, Biochemical, and Echocardiographic Findings in Dogs Infected with Dirofilaria spp.

Abstract

Canine dirofilariasis is a significant disease that associate with heart and cardiopulmonary complications. In endemic regions, the co-occurrence of other vector-borne infections further complicates diagnosis and treatment. Additionally, the lack of standardized diagnostic tools to assess disease progression represents a critical gap in veterinary literature. In this study echocardiographic, hematological, and biochemical findings of dogs infected with heartworm alone and those co-infected with other vector-borne diseases were compared. Furthermore, the study aimed to evaluate the usability of these parameters in determining the prognosis and severity of the disease. This study included 12 dogs diagnosed with Dirofilaria spp. infection, categorized into two groups: mono-infected (n=7) and co-infected (n=5). Dirofilaria antigens and additional co-infecting agents were detected using the Knott test and SNAP 4Dx, and blood samples were collected for complete blood count (CBC) and serum biochemistry analysis. Each dog underwent an echocardiographic evaluation. While most parameters were similar between the mono-infected and co-infected groups, platelet (PLT) counts and mean corpuscular hemoglobin concentration (MCHC) values were lower, and liver enzyme levels were higher in the co-infected group. Although echocardiographic parameters were generally similar, the mono-infected group showed higher left atrial dimensions and ventricular volumes, while the co-infected group exhibited slightly elevated fractional shortening (FS) and ejection fraction (EF) values. These findings suggest that co-infection may influence both platelet counts and liver enzyme levels. This study indicates that co-infections in dogs with dirofilariasis may lead to lower PLT and MCHC levels, accompanied by higher liver enzyme levels, which could impact disease management approaches.