First of all - what is a biopsy?
A biopsy is a surgical procedure used in dogs to obtain a tissue sample for diagnosis of a variety of pathologies, from cancer to skin disease. The goal of biopsy is to provide a veterinary pathologist an accurate picture of the disease process taking place so that they may report the suspected disease or type and stage of cancer in your dog. Biopsy is a common procedure often used to diagnose dermatological issues and certain cancers. Your veterinarian will perform the biopsy (or refer to a veterinary surgeon for more involved biopsy) and then submit the tissue sample obtained from biopsy to a veterinary pathologist for interpretation.
Why would the vet choose the iliac crest?
The iliac crest, rib and sternum were compared as sites for bone marrow biopsy in the dog using ten males and ten females of varying ages. It was concluded that the iliac crest was the easiest and safest of the three biopsy sites.
What could abnormal number of cells in the bone marrow indicate? White blood cells help fight infection and respond when an area of the body becomes inflamed.
Elevated white blood cell counts indicate infection, inflammation and some forms of cancer or leukemia. Low white blood cells counts can indicate viral infections, bone marrow abnormalities or overwhelming infections and sepsis (blood poisoning).
A dog's white blood cells (WBC’s), often referred to as leukocytes, act as a brave company of soldiers whose main goal is to defend your dog's body from potential enemies such as viruses, bacteria or fungi.
While there are several types of leukocytes, a total white blood cell count, as its name implies, shows the total of all types of white blood cells. The normal numbers of white blood cells in a dog may range between 6,000 and 17,000 per microliter.
Generally a high number of leukocytes in a dog may be indicative it fighting an infection. When a dog's body detects the presence of enemies, it gathers all the troops up so that their huge numbers heighten the chances for defeating the enemy.
Affected dogs often display a fever greater than 103 degrees, act lethargic and lose their appetite. If the dog's symptoms point to an infection the vet will likely prescribe a round of antibiotics. However, infections aren't the only cause for high white blood cell counts in dogs and not all infections cause the levels to become higher.
As part of the body’s immune system, white blood cells provide defence against disease. A drop in the total number of circulating white blood cells, called leukopenia, puts the dog at a higher risk of infection. As well as the overall count, blood tests will measure the number of each particular type of cell.
Neutrophils are the most numerous white blood cell in dogs. They are the first cells to respond to an infection, travelling quickly to the site and binding to the foreign bacteria or virus that is causing the problem. Neutrophils are short-lived cells, generated in large numbers by the bone marrow. A low number of neutrophils, called neutropenia, is the most common reason for leukopenia in dogs. Many acute or long-lasting infections can cause neutrophil numbers to drop because the cells are destroyed faster than the bone marrow is able to compensate. Autoimmune responses, genetic disorders found in some breeds, cancer, and drug toxicity can also cause neutropenia.
With disorders that affect the bone marrow, the condition may be combined with low levels or red blood cells and platelets as well, since the stem cells in the bone marrow may be unable to generate any type of blood cell. While leukopenia is not a definitive diagnosis, analyzing the numbers and different types of blood cells that are present will help the veterinarian identify your dog’s disease.
A drop in the total number of circulating white blood cells, called leukopenia, makes a dog more susceptible to any type of infection. Neutropenia, low numbers of the white blood cells called neutrophils, is the most common type of leukopenia in dogs. This disorder is usually the result of an underlying cause, such as infection, cancer, or a genetic abnormality.