This paper describes five naturally occurring clinical cases of infectious canine
cyclic thrombocytopenia that were the first serologically confirmed cases of Ehrlichia platys
infection in Israel. In the USA this disease is considered subclinical, but the dogs in this study developed distinct clinical abnormalities. The signs observed by the owners included
anorexia,
lethargy, depression,
weight loss and a mucopurulent nasal discharge. The principal findings on physical examination included lymphadenomegaly, pale mucous membranes,
fever and the presence of ticks. The main abnormal haematological and biochemical findings included
thrombocytopenia, the presence of giant platelets, low haematocrit, monocytosis and low
albumin concentrations. All five dogs were less than two years of age, and four were purebred dogs, suggesting that these two factors may be associated with increased risk to
infection and clinical disease. Two of the dogs were seropositive to E canis, a finding which is compatible with other reports, and which confirms that combined
infections of E platys and E canis are common; it also suggests that E canis
infections may contribute to the pathogenesis of E platys. The distinct clinical manifestation of the disease in these five dogs suggests that there may be a different, more virulent strain of E platys in Israel.