Understanding Abnormal Cat Bleeding: Causes and Solutio
Abnormal bleeding in cats, often referred to as hemostasis disorders, occurs when the blood fails to clot properly. This condition can manifest in various forms of bleeding across the skin, mucous membranes, tissues, body cavities, and internal organs within a cat's body. When hemostasis issues affect the membranes of the skin, mouth, nose, eyes, and external genitalia, the bleeding can be observed directly. In cases of gastrointestinal bleeding, a cat may suffer from hematochezia (fresh blood in the stool) or melena (dark, tarry stools). Similarly, if the urinary tract is affected, you might notice blood in the cat's urine, a condition known as hematuria.
The impact of abnormal bleeding in cats can range from mild to severe, depending on the extent of blood loss. Bleeding caused by accidents or unknown reasons requires prompt diagnostic evaluation to determine if there is a clotting abnormality. Many clotting disorders are serious, as they can lead to lifethreatening bleeding situations.
Causes of Abnormal Bleeding in Cats
The causes of abnormal bleeding can be categorized into platelet abnormalities, vascular wall abnormalities, and coagulation factor abnormalities. Platelets are tiny particles in the blood that can clump together at the site of a vascular wall breakage to form a clot. Coagulation factors are various proteins involved in the blood clotting process, which become activated during bleeding, bind with platelets, and plug the leak in the blood vessel. Fortunately, these three types of clotting abnormalities are not commonly seen in cats.
Reason 1: Platelet Disorders
Platelet disorders occur when platelet counts are low or when platelets do not function normally. The reasons for low platelet counts include insufficient production in the bone marrow, platelet destruction, or premature removal from the bloodstream. Platelet dysfunction can be a congenital, inherited condition or a condition that develops later in life.
Conditions that can lead to reduced platelet counts include:
Ingestion of drugs toxic to the bone marrow
Infection of the bone marrow by certain bacteria, viruses, and rickettsiae
Immunemediated destruction of the bone marrow
Bone marrow cancer
Myelitis and bone marrow fibrosis, where bone marrow cells scar and disappear
Conditions that can increase platelet destruction include:
Immunemediated destruction of platelets (rare in cats)
Ingestion of certain drugs that damage platelets
Some viral infections
Conditions that can cause platelets to be prematurely cleared from the bloodstream include:
Vasculitis
Some parasitic infections
Disorders of the spleen
Diseases affecting platelet function include:
Congenital platelet dysfunction (ChediakHigashi syndrome in cats)
Drug toxicity
Some infectious diseases
Renal failure
Liver failure in cats
Some leukemias
Reason 2: Vascular Disorders
Most vascular disorders weaken the vascular wall, leading to abnormal bleeding. A smaller number of diseases cause bleeding by increasing blood pressure, as high blood pressure can cause blood to burst through the vascular wall, exacerbating bleeding symptoms.
Diseases that weaken the vascular wall include:
Vasculitis – inflammation of the blood vessels
Adrenal cortical hyperplasia – a disease where the adrenal glands secrete excessive cortisol hormones (rare in cats)
Cat diabetes – a form of diabetes mellitus
Uremia – when the kidneys fail to remove waste products in a timely manner
Reason 3: Coagulation Factor Disorders
Diseases associated with coagulation factor disorders include:
Hereditary coagulation factor deficiencies leading to hemophilia (rare in cats)
Products related to warfarin that inhibit the presence of vitamin K, which is essential for the activity of coagulation factors. This is the most common cause of bleeding issues in cats. It can occur when cats eat rodents poisoned by warfarin or similar toxins, or when they ingest substances containing warfarin or similar poisons directly.
Liver diseases that prevent the production of coagulation factors
Disseminated intravascular coagulation (DIC) – a widespread bleeding caused by the consumption of platelets and coagulation factors