Leucocytosis

Leucocytosis (leukocytosis) in dogs is defined as a marked elevation in all circulating leucocytes (white cells) in the blood > 17 x 10⁹/L.

Leucocytosis generally infers the presence of neutrophilia, lymphocytosis, monocytosis and thrombocytosis.

The converse to leukocytosis is leukopenia.

There are many causes of leucocytosis, and although this is frequently interpreted as a response to infection, particularly bacterial, there are other causes, including:

• Parasites
• Fungal infections
• Neoplasia

- e.g. Leukemia, lymphoma

• Immune-mediated hemolytic anemia