Causes of Abdominal Bleeding in Dogs

A higher incidence of hemoabdomen has been observed in senior dogs. More cases have also been diagnosed in Golden and Labrador Retrievers, and German Shepherds.

The causes of abdominal bleeding (hemoabdomen) in dogs are divided into two major categories - traumatic and spontaneous causes.

• Traumatic Hemoabdomen: The most common cause of this type of hemoabdomen is a traumatic injury, such as when a dog is hit by a car, a gunshot, or a fall. Surgery is sometimes required for this type of hemoabdomen, but often the blood is reabsorbed by the body.
• Spontaneous (Non-Traumatic) Hemoabdomen: This is the more common type of hemoabdomen in dogs. The cause is often the rupture of a tumor that is growing in any of the abdominal organs. Profuse bleeding can lead to substantial blood loss and pooling of blood in the abdominal cavity.

Common Tumors That Cause Abdominal Bleeding in Dogs

Benign Tumors

• Splenic hematomas
• Hemangiomas
• Tumors of the liver or adrenal glands

Malignant Tumors

• Splenic hemangiosarcoma - This is the most common malignant tumor that causes abdominal bleeding in dogs
• Hemangiosarcoma originating in the liver or other parts of the abdomen
• Hepatocellular carcinoma (liver cancer)
• Adrenocortical carcinoma (arises from the adrenal glands)
• Pheochromocytoma

Tumors in the Spleen

The rupture of a mass in the spleen is the most common cause of hemoabdomen in dogs. Splenic tumors can be benign (hemangiomas) or malignant (hemangiosarcomas, mast cell tumors, and lymphosarcoma).

Hemangiomas and hemangiosarcomas are the most common splenic masses in dogs. The spleen is composed of red pulp and white pulp. Both of these tumor types develop from the blood vessels of the red pulp. The tumor is made up of abnormal blood vessels that are wildly proliferating. Eventually, the growth ruptures, leading to bleeding of the spleen. Take note that the spleen is a highly vascular organ. When there is bleeding in the spleen, there is a very high risk for life-threatening blood loss.

Signs of Bleeding in the Spleen

• Weakness
• Hypothermia - abnormally low body temperature
• Pale or bluish gums

Sometimes, the bleeding in the spleen will stop on its own. But it will surely bleed again if surgical intervention is not performed. There is a need to remove the spleen to prevent the dog from bleeding to death. Removing the spleen is a viable option as long as the dog has not lost too much blood to survive the procedure.

Ideally, any growth in the spleen should be detected before it has started to bleed. Surgical removal of the spleen is generally done when the tumor is not actively bleeding. However, if it’s actively bleeding, emergency surgery should be performed immediately.

Diagnosing a Splenic Mass

A splenic mass can be an incidental finding during a routine physical exam. Your vet may feel the large, firm mass when palpating your dog’s abdomen. To know more about the problem and determine its extent and severity, the following procedures are often performed:

• Abdominal x-rays are performed to determine where the mass is located.
• Chest x-rays are also taken to check for evidence of metastasis (spread of cancer to the lungs).
• An ultrasound can confirm if there is fluid within the abdominal cavity and where it’s coming from.
• Blood biochemistry is also an important diagnostic tool. The results of these tests and procedures can help your vet decide whether the removal of the spleen can be performed or not.

Treating Splenic Tumors

Considering that a moderate percentage of tumors in the spleen are benign, surgery should be a treatment option because splenectomy is curative in this case. If during surgery, there is no evidence of metastasis (tumor spread), the spleen can be removed, and chemotherapy can be started to maximize the dog’s longevity and quality of life if malignancy is confirmed.

Chemotherapy, however, is not a reasonable treatment option if the primary tumor in the spleen cannot be removed. Eventually, bleeding may recur from which the dog cannot recover.

Bleeding Abnormalities in Dogs

The most common cause of coagulopathies that lead to hemoabdomen in dogs is the ingestion of toxins that interfere with the proper clotting of blood. Toxins that cause coagulopathies include rat poison and coumadin (a heart medication for humans).

Bleeding in affected dogs may be superficial and/or within body cavities (hemoabdomen). Treatment will include the administration of vitamin K to promote blood clotting. Blood transfusions may be needed if there is extensive loss of blood.

Other Causes of Internal Bleeding in Dogs

Bleeding in the abdomen of dogs may also be a result of torsion, a condition in which an organ twists on its long axis, like what is seen in spleen torsion and gastric dilatation-volvulus (commonly called ‘bloat’).

Can dogs with internal bleeding survive?

Following surgery, your dog will need intensive care to address any symptoms that may develop. This may include continued blood loss and post-operative pain. If hemoabdomen is caused by trauma in the abdomen, additional surgery may be necessary.

In dogs with non-traumatic hemoabdomen, the short-term prognosis is generally good as long as there are no complications after surgery. However, the long-term prognosis will depend on the underlying cause of the bleeding in the abdomen. Prognosis is generally good for dogs with benign causes.

Hemangiosarcoma is an aggressive type of cancer. While removing the tumor can prevent the dog from dying of hemorrhage, the patient eventually succumbs to cancer. The survival times of dogs with hemangiosarcoma can be variable depending on the dog and if additional treatment options, such as chemotherapy, have been pursued. Fortunately, dogs with malignant causes can still have a relatively normal quality of life after surgery, until metastatic tumors start to develop. When this happens, euthanasia is generally recommended.

Read more:

Intestinal Cancer in Dogs and Cats

Common Causes of Coughing in Dogs

Melanoma in Dogs

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