Which sign might indicate the chronic phase of Canine Ehrlichiosis?

Severe thrombocytopenia is a key indicator of the chronic phase of Canine Ehrlichiosis. In this disease, caused by the bacterium Ehrlichia canis, the immune system becomes compromised over time. Thrombocytopenia, which refers to a significant decrease in platelet count, is a common hematological abnormality observed in chronically affected dogs.

During the chronic phase, this low platelet count can lead to symptoms related to increased bleeding risk, such as petechiae, ecchymoses, and excessive bruising. It's a critical sign that demonstrates how the disease can affect the bone marrow's ability to produce platelets and suggests a longer duration of infection.

The other signs listed, such as edema of the limbs, fever, and depression, might be seen in different stages of the disease or with other conditions but do not specifically indicate the chronic phase. Fever and depression are often associated with a more acute response to infection, while limb edema can occur due to a variety of factors and is not exclusive to the chronic stage of this disease. Understanding the hematological changes that occur in chronic Canine Ehrlichiosis helps in the diagnosis and management of affected dogs.