Overview of Bruising and Bleeding in Dogs
Abnormal bruising and bleeding arises with disorders of hemostasis (clotting) in dogs. Clotting abnormalities are also called coagulopathies, because they reflect the inability of the blood to coagulate or clot. Bleeding from clotting disturbances may occur into the skin, the mucous membranes, and various internal organs, tissues, and body cavities. When the bleeding occurs into the skin, the membranes of the mouth, nose, eyes and external genitalia it may become visible to the owner. Bleeding into the intestinal tract may appear as hematochezia (fresh blood in the stools) or melena (dark, tarry stools). Bleeding into the urinary tract may be detected as blood in the urine (hematuria).
The impact of such bleeding on the affected individual may be mild or severe depending on the degree of blood loss. Unexpected or unexplained bruising warrants examination of the animal by your veterinarian in order to determine if a clotting abnormality exists. Many clotting abnormalities are serious because they may predispose the animal to a life-threatening episode of bleeding.
Causes of Abnormal Bleeding and/or Bruising in Dogs
The causes of bruising and bleeding can be classified as platelet disorders, vessel wall disorders, or clotting factor disorders. Platelets are small particles in the blood that begin the formation of a blood clot by clumping together at the site of any break in the blood vessel wall. Clotting factors are proteins in the blood that are responsible for further development of a clot after the platelets have initiated the process.
Platelet disorders can arise when platelet numbers are decreased, or platelets fail to function properly. Platelet numbers are decreased when they are not produced adequately in the bone marrow, when they are destroyed, or when they are prematurely removed from the circulation. Dysfunction of platelets can occur as an inherited, congenital disorder, or may develop as an acquired condition later in life.
These disorders cause a decrease in the production of platelets:
These disorders result in increased platelet destruction:
These disorders cause increased removal of platelets from the circulation:
Disorders that affect the function of platelets include the following:
Vascular disorders usually result in abnormal bleeding by weakening the walls of the blood vessels. In some instances the underlying disease may also increase blood pressure, which aggravates any bleeding tendency. Disorders that increase the fragility of blood vessel walls include the following:
Clotting Factor Disorders
What to Watch For
Diagnosis of Bruising and Bleeding in Dogs
There are many tests that may be recommended for the patient with abnormal bruising or bleeding. The following is a list of the tests that are often performed initially:
Treatment of Bruising and Bleeding in Dogs
There are several things your veterinarian might recommend to treat the patient with bruising/bleeding symptomatically while the diagnostic work up is underway. These supportive measures include the following:
Any sign of bruising or bleeding should be evaluated in a timely fashion by your veterinarian. Administer only medications that your veterinarian has recommended and do not allow your pet to have exposure to rat poison and other toxins that can cause bleeding.
In-depth Information for Bruising and Bleeding in Dogs
Inappropriate bruising or bleeding arises in animals for many reasons, including disorders associated with platelets, clotting factors, or the vessels in which blood travels. These disorders are not common, but can occur in any age or breed of dog.
Bruising or bleeding may occur in association with many systemic illnesses or disorders. Clinical signs may be mild and subtle, such as a small bruise on the skin, or signs may be severe and life threatening. Unexplained or abnormal bruising or bleeding should never be ignored. Examination by a veterinarian should be sought immediately in pets that appear to be pale, lethargic, weak, or in distress.
When evaluating an animal with abnormal bleeding, it is important to establish a definitive diagnosis as to the type of clotting abnormality present, and to identify any underlying causes. The therapy of coagulopathies varies, and must address not only the underlying cause, but must also treat the specific defect in clotting.
In-depth Information on the Causes of Canine Bleeding
There are many causes of bruising and bleeding. Although it is not unusual for a normal cat or dog to have a small bruise or an occasional fleck of blood in the stool, it is not normal or acceptable for bleeding to be widespread, prolonged, severe, or recurrent.
Platelet disorders are the most common disorders associated with bleeding or bruising. Platelet disorders can arise when platelet numbers are decreased or when platelets fail to function properly. Platelet numbers are decreased when they are not produced adequately in the bone marrow, when they are destroyed, or when they are prematurely removed from the circulation. Thrombocytopenia is defined as a decreased platelet count. Generally speaking, animals with platelet counts less than 25,000 may bleed spontaneously and are at risk for life-threatening hemorrhages.
Dysfunction of platelets can occur as an inherited, congenital disorder, or may develop as an acquired condition later in life.
Disorders that Decrease Platelet Numbers or Function
Clotting Factor Disorders
Diagnostic Tests In-depth
There are many tests that may be recommended for the patient with bruising or bleeding. The following is a list of the most common tests that should be performed first.
Your veterinarian may recommend additional tests to insure optimal medical care. These are selected on a case-by-case basis.
One or more of the diagnostic tests described above may be recommended by your veterinarian. In the meantime, treatment of the symptoms might be needed, especially if the problem is severe. The following nonspecific (symptomatic) treatments may be applicable to some but not all pets with bruising and bleeding. These treatments may reduce severity of symptoms or provide relief for your pet. However, nonspecific therapy is not a substitute for definitive treatment of the underlying disease responsible for your pet's condition.
Home Care for Dogs with Bleeding or Bruising
Optimal treatment for your dog requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your dog does not rapidly improve. It is important to note that bruising or bleeding may lead to life-threatening consequences.
It is important to monitor your dog very closely and note the frequency, severity, or intensity of bruising and/or bleeding. The easiest places to monitor for bruising and bleeding in dogs are places on the body without hair or with minimal pigmentation. The gums, inner ear flaps, and the less haired places on abdomen are good places (especially the belly between the rear legs). Also monitor the urine, vomit and feces for any signs of bleeding.
Administer all prescribed medications as directed. Alert your veterinarian if you are experiencing problems treating your dog. Never use medications that your veterinarian has not recommended. It is important to use the medication only at the dosage and frequency recommended.
Return for follow up visits as directed by your veterinarian. Repeated measurement of platelet counts and clotting tests may be of utmost importance in some cases.
Avoid any medications or substances that may be cause or exacerbate (worsen) bleeding and other clinical signs.
Do not breed dogs with inherited bleeding disorders.