Secondary subclinical diabetes mellitus in dogs infected with Ehrlichia canis

Ehrlichiosis is an important and potentially fatal disease of dogs caused by the rickettsia Ehrlichia canis. This disease has a worldwide distribution and pathogenic mechanism involves haematological alteration that may occur due to immune mediated inflammatory changes and hormonal alterations. Diabetes mellitus is a frequently occurring endocrinopathy in dogs. Non insulin dependent diabetes mellitus is very rarely reported in dogs. The present study aims at evaluation of diabetic biomarkers like fasting blood glucose, glycated haemoglobin,serumfructosamine,serum insulin and oral glucose tolerance test in E. canis infected dogs. Out of 67 dogs screened, 26.8% showed antibodies to E.canis by SNAP 3DX test.But only 8.9% of dogs demonstrated morulae in the buffy coat smear indicating antibody test is more sensitive compared to buffy coat smear examination. Out of 18 dogs infected with E.canis, 77.7 % of dogs exhibited subclinical diabetes with biomarkers above the range in healthy animals, but below the level in clinical diabetes. These animals also showed higher insulin level signifying insulin resistance. Future research is warranted to identify the factors contribute to insulin resistance in E.canis infection in dogs.