Bruising and Bleeding in Dogs

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

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:

• Drugs toxic to the bone marrow
• Infection of the bone marrow with certain bacteria, viruses, and rickettsia (e.g. ehrlichiosis)
• Immune mediated destruction of the bone marrow
• Cancer of the bone marrow
• Myelophthisis and myelofibrosis, which are scarring and disappearance of bone marrow cells
• Excessive estrogen hormone influence on the bone marrow

These disorders result in increased platelet destruction:

• Immune-mediated destruction of platelets
• Certain drugs
• Certain viral infections

These disorders cause increased removal of platelets from the circulation:

• Ehrlichiosis in dogs
• Vasculitis
• Certain parasites
• Certain disorders of the spleen

Disorders that affect the function of platelets include the following:

• Congenital platelet function disorders
• Certain drugs
• Some infections
• Kidney failure
• Liver failure
• Certain leukemias

Vascular Disorders

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:

• Vasculitis – inflammation of blood vessels
• Hyperadrenocorticism – a disease where the adrenal glands produce too much cortisone hormone in the body
• Diabetes mellitus – sugar diabetes
• Uremia – an increase in waste products not cleared by diseased kidneys

Clotting Factor Disorders

• Inherited deficiencies of clotting factors that result in hemophilia
• Toxicity with warfarin or warfarin-like products that antagonize Vitamin K
• Liver disease that prevents the manufacture of clotting factors
• Disseminated intravascular coagulation (DIC), which is widespread bleeding due to the consumption of platelets and clotting factors
• Von Willebrand’s disease, which arises from a deficiency of a factor needed for proper platelet function

What to Watch For

• Blood in the urine or stool
• Nose bleed (epistaxis)
• Bruises or swelling on or under the skin
• Pin point or blotchy hemorrhages on the gums of the mouth
• Pinpoint or blotchy hemorrhages on the membranes of the vulva and penis
• Pinpoint hemorrhages on the whites of the eyes or the inside of the eyelids
• Bleeding into the front chamber of the eye
• Difficulty breathing with bleeding into the lungs or chest cavity
• Abdominal distension with bleeding into the abdomen
• Weakness, depression
• Pale gums from anemia
• Excessive or unrelenting bleeding from a cut or wound
• Swollen and painful joints from bleeding into the joints

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:

• Complete blood count (CBC)
• Platelet count
• Biochemical profile
• Urinalysis
• Thoracic (chest) and abdominal radiographs (x-rays)
• Fecal tests
• Coagulation studies that measure how long it takes for the blood to clot
• Serologic tests for infectious diseases that can affect clotting
• Abdominal ultrasonography
• Bone marrow aspiration and cytology
• Von Willebrand’s factor assay
• Assays of clotting factors

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:

• Discontinue any medications that may cause a bleeding problem.
• Minimize activity to reduce the risk of even minor trauma.
• If an animal is severely anemic or weak from excessive bleeding, it may be necessary to hospitalize the patient for the administration of intravenous fluids, transfusions of blood products, and institution of other stabilizing measures, such as oxygen therapy, vitamin K therapy, and administration of antidotes to toxins.

Home Care

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

• Immune mediated destruction of circulating platelets or the cells of the bone marrow that form platelets
• Various disorders of the cells of the bone marrow, such as cancer, myelophthisis and myelofibrosis
• Viral infections – canine distemper virus, parvovirus
• Bacterial infections – Salmonella
• Rickettsial infections – ehrlichiosis
• Certain parasites – heartworm disease, Plasmodium infection
• Neoplasia (cancer) in the body
• Drugs that alter platelet production or function – estrogen, trimethoprim/sulfas, chemotherapeutic drugs, phenylbutazone, aspirin and other nonsteroidal anti-inflammatory drugs, azathioprine, albendazole, etc.
• Hormonal imbalances, such as excessive production of estrogen as seen in hypothyroidism
• Disorders of the spleen
• Vasculitis (inflammation of the vessels)
• Disseminated intravascular hemolysis (DIC), a complex, life threatening hemostatic defect that occurs secondary to many systemic diseases
• Congenital platelet function disorders of the basset hound, foxhound, otterhound, Great Pyrenees, Scottish terrier, etc.
• Kidney disease
• Liver disease
• Vaccination with modified live viruses

Vascular Disorders

• Vasculitis – inflammation of blood vessels
• Hyperadrenocorticism – a disease where the adrenal glands produce too much cortisone hormone in the body
• Diabetes mellitus – sugar diabetes
• Uremia – an increase in waste products not cleared by diseased kidneys

Clotting Factor Disorders

• Inherited deficiencies of clotting factors that result in hemophilia
• Toxicity with warfarin or warfarin-like products that antagonize Vitamin K
• Liver disease that prevents the manufacture of clotting factors
• Disseminated intravascular coagulation (DIC), which is widespread bleeding due to the consumption of platelets and clotting factors
• Von Willebrand’s disease, which arises from a deficiency of a factor needed for proper platelet function

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.

• Complete medical history (including travel history, toxin exposure, environment) and thorough physical examination
• A complete blood count (CBC) to evaluate for the presence of systemic infection or inflammation. This test may reveal anemia secondary to bleeding, and may show changes in other cell lines such as the white blood count that might be indicative of other or concurrent disorders.
• A biochemical profile to evaluate kidney, liver, electrolytes (specifically, potassium and calcium), total protein, and blood sugar status. All of these parameters are important to establish in the bruising or bleeding patient, and to rule out the possibility of concurrent diseases.
• A urinalysis to evaluate the kidneys, hydration status of the patient, and confirms or rules out the presence of blood.
• Thoracic (chest) and abdominal radiographs (x-rays). Although they may be within normal limits, they may reveal evidence of lymphadenopathy (enlarged lymph nodes), and liver and/or splenic enlargement. In addition, it is important to rule out other diseases and causes of the patients’ clinical signs as well.
• Abdominal ultrasound. It is very helpful in evaluating all of the abdominal organs, including the liver, kidneys, lymph nodes and spleen. It is equally important to rule out other disorders or diseases that may be associated with bruising or bleeding. Abdominal ultrasound is a noninvasive test that often needs the expertise of a specialist and/or referral hospital.
• Coagulation (clotting) studies (APTT, PT, platelet count) to better understand the underlying cause of bleeding, and/or to determine if there is concurrent DIC.
• A bone marrow aspirate in the patient with thrombocytopenia or hyperglobulinemia (high globulin part of the protein fraction). This relatively noninvasive test allows us to sample the marrow (substance inside of the bone), which is responsible for producing red blood cells, white blood cells and platelets. With a local anesthetic, a small needle is introduced into the core of the bone, and a small amount of marrow is withdrawn and analyzed. There are characteristic changes consistent with ehrlichiosis that one may see. It is important to rule out other disorders, such as multiple myeloma or chronic lymphocytic leukemia that can initially be difficult to differentiate from ehrlichiosis. This test may be performed by your local veterinarian, although in some cases, may be best to have performed in a specialty hospital.

Your veterinarian may recommend additional tests to insure optimal medical care. These are selected on a case-by-case basis.

• Endocrine testing to include an ACTH stimulation test and a thyroid profile to rule out hyperadrenocorticism (Cushing’s disease) and hypothyroidism, respectively. They are blood tests that can usually be performed at your local veterinary hospital. Both Cushing’s disease and hypothyroidism are endocrine disorders that are commonly seen in veterinary medicine, and can be associated with bleeding or bruising.
• Protein electrophoresis. This blood test should be considered in animals with high protein levels (especially globulins) and may be helpful in diagnosing certain disorders such as multiple myeloma or ehrlichiosis.
• Platelet function tests. These blood tests should be run on selected patients to rule out plate function disorders.
• Von Willebrand’s factor assay is a blood test that is necessary to confirm Von Willebrand’s disease.

Therapy In-depth

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.

• Generally speaking, treatment for the bleeding or bruising patient is done on an inpatient level until the underlying cause has been identified and/or addressed.
• Minimize activity to reduce the risk of even minor trauma.
• If an underlying cause has been identified, treat or remove it if possible.
• Discontinue any medications that may cause bleeding or bruising.
• Blood products may be necessary in patients who are profoundly weak and anemic secondary to excessive bleeding or bruising, and should be administered even before a definitive diagnosis has been established in some cases.

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.