Anemia Due To Deformed Red Blood Cells in Dogs

Rather than a disease itself, anemia is usually a symptom of another underlying problem. Depending on the cause, deformed or abnormally shaped blood cells can be present with many different types of anemia. These cells contribute to the anemia since their shape makes them less able to transport oxygen. In some cases the deformity may have been present from the cell’s formation; in others, it is the result of damage or injury during the process of circulation. Poikilocyte is a generic name for an abnormally shaped or deformed blood cell, but veterinarians try to categorize these cells more specifically based on their shape. Spiculated or spiked cells are often present with spleen cancer (hemangiosarcoma) and lymphosarcoma, as well as diseases of the kidney and liver. Metabolic conditions like iron or phosphorus deficiency also increase the fragility of red blood cells and make them more prone to injury and malformation. Deformed red blood cells can’t be used as a specific diagnosis, but they will help the veterinarian find the cause of your dog’s anemia.

Deformed blood cells contribute to anemia since they are unable to properly transport oxygen. Veterinarians define any abnormally shaped red blood cell as a poikilocyte. Further definitions categorize cells based on their specific shape. Anemia with deformed red blood cells is often associated with cancer of the spleen, and kidney or liver disease.

If you notice any of the traditional symptoms of anemia, take your dog to see a veterinarian immediately.

• Poor Appetite
• Weight loss
• Lethargy
• Lack of stamina
• Weakness
• Rapid heart rate (tachycardia)
• Rapid breathing (tachypnea)
• Paleness of mucus membranes, especially notable around the gums
• Blood in the stool

Types

Veterinarians define deformed cells in terms of their structure, but there is a certain amount of variation in terminology. These are the most common types of deformed blood cells which can cause anemia, as well as the conditions with which they are often associated.

Acanthocytes (also called spur cells or irregularly spiculated cells) –  irregular long  protrusions:

• Cancer of the spleen, liver, or kidneys, especially hemangiosarcoma
• Non-cancerous tumors in these areas
• Iron deficiency

Echinocytes (burr cells, regularly spiculated cells, or crenation) – regular short protrusions:

• Kidney disease
• Chemotherapy
• Lymphoma
• Old or drying blood

Schistocytes – fragmented blood cells:

• Hemangiosarcoma
• Heartworm
• HyposplenismLiver disease
• Increased blood coagulation

Spherocytes – small sphere shaped red blood cells with part of the membrane removed:

• Immune Mediated Hemolytic Anemia (IMHA)

In some cases, veterinarians don’t know the exact mechanism which causes deformed blood cells to form. Studies show that alterations in the lipid construction which occurs with liver disease can make blood cells cell more malleable and likely to become damaged. It is generally believed that damage occurs after formation. Fragmented and spiculated cells are often found together with spleen cancer.

It’s also believed that spherocytes form when the blood recycling process normally carried out by the spleen goes awry during IMHA. Antibody covered blood cells marked by the immune system are only partially destroyed by the spleen. A small number of these cells can be present in normal blood, but high numbers are a good indication of IMHA.

A complete blood cell count will be used to diagnose your dog’s anemia. The veterinarian will use a blood smear test to look for deformed or misshapen red blood cells. If high levels of acanthocytes and schistocytes are found, the veterinarian will likely order x-rays or ultrasound to check for hemangiosarcoma or other tumors on the spleen, kidneys or liver. Biopsies may also be needed to confirm the results of the X-rays, as well as urine tests to check for kidney or liver disease if a cancer diagnosis is inconclusive. High numbers of spherocytes will require further tests that can definitively diagnose IMHA. Other blood test results such as iron deficiency or additional symptoms could make the veterinarian decide to investigate other possible causes. 

The veterinarian will need your dog’s complete medical history as well as any drugs he is taking. Accurately describing the nature and onset of the anemia symptoms will also be helpful. Unless there is an obvious source of the anemia, diagnosing the cause can include a number of eliminative tests.

Treatment will depend on the cause of the anemia. Treatment of hemangiosarcoma or other cancers of the kidneys or liver could involve surgery and/or chemotherapy. In many cases, tumors have already spread beyond the point of surgery by the time they are discovered, and supportive treatment of the symptoms is all that’s possible.

Some conditions may need to be managed with medication. Various medications are used to reduce kidney and liver disease. Dialysis appointments may be recommended in the advanced stages of kidney failure. IMHA could require long term immune suppressant treatment. Other conditions may require diet change or nutrition supplement. Very severe cases of anemia will need immediate blood transfusion to stabilize the blood.

Recovery will also be dependent on the cause. High numbers of deformed blood cells are usually a sign of a serious disease such as cancer or organ failure. It's unlikely that your dog will make a full recovery from a condition like this, although it may be able to be managed medically for a number of years. Minor metabolic imbalance may be easily rectified with supplements or diet change. 

The prognosis will be dependent on the evaluation of a veterinarian. Regular blood tests to check for anemia are a good idea whatever the outcome. This can help to catch problems before they become severe.