There are two forms of canine leukemia – Acute and Chronic. The Acute form of the disease will normally develop very quickly and can lead to a variety of debilitating symptoms ranging from milder symptoms such as general lethargy and tiredness to more serious symptoms such as hemorrhaging and bleeding from internally and externally.
Canine leukemia develops due to the amount of white blood cells in the dog’s blood or bone marrow being produced at an abnormal rate. Due to the surge in the amount of white blood cells being produced this can damage the blood and the bone marrow. This extremely serious condition is caused by the bone marrow becoming genetically mutated – the condition can also affect the lymph nodes. One of the primary functions of the white blood cells (which are also known as leukocytes) is to protect the dog’s body from nasty bacteria, microorganisms, viruses and fungi so if they are not functioning properly this weakens the dog’s ability to protect itself.
Leukemia can affect all of the different types of white blood cells including the basophils, eosinophils, platelets, monocytes and lymphocytes. Each of these different cell types can develop a ‘cell-specific’ type of leukemia – for example if the lymphocytes or white blood cells have experienced a malignant transformation then lymphoid leukemia may develop. It is important to mention that the Acute and Chronic form of the condition are fairly rare in dogs.
Signs and symptoms
This condition is more common in middle-aged dogs (around the age of six years of age) and the symptoms can vary. However, the most common symptoms of the condition can include fever, anemia, weight-loss, increased heart rate, diarrhea, vomiting, tiredness, pale mucus membranes, increase respiratory rate, enlarged lymph nodes, dehydration, increased thirst and urination, lameness, enlarged liver and spleen and finally internal and external bleeding.
Diagnosis & treatment
The most effective method utilised by vets to diagnose canine leukemia is through a bone marrow biopsy. This will be achieved through a fine hollow needle being inserted into the marrow so that a biopsy can be removed. Cytology tests will then be undertaken to determine whether the dog has leukemia. Due to the possible upset and pain this can cause the dog will need to be sedated or under anaesthetic when the procedure is performed.
Another method to help form an accurate diagnosis will be through the vet taking blood or urine samples. A positive diagnosis will be formed when increased numbers of leukemic cells are found in the blood.
Of course any accurate diagnosis will be supported through a thorough physical examination and medical history. If the dog is experiencing any of the symptoms previously mentioned including enlargement of the lymph nodes then this will help to support any more invasive diagnostic tests.
The treatment for canine leukemia will normally include anti-cancer drugs being prescribed. Although chemotherapy is not effective in curing the condition it can help to put the condition in remission which can last for months or even longer.
Any secondary symptoms such as anemia may need to be treated through blood transfusions and of course if the dog is dehydrated or not eating then fluids and food will need to be encouraged. It may be necessary for the vet to use intravenous fluids to rehydrate the affected dog. Unfortunately dogs that do develop leukemia may not survive as the prognosis of Acute canine leukemia is particularly poor and as with many health conditions the condition may have developed to a more advanced stage before diagnosed (leading to a worst prognosis). Unfortunately if the Acute form is not noticed, diagnosed and treated early the life expectancy can be as little as one month.
Chronic canine leukemia does have a better prognosis than the Acute form as it tends to develop at a slower rate giving the affected dog a better fighting chance.