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DISEASES OF THE BLOOD AND SPLEEN
By definition, an anemia occurs when the amount of red blood cells in the blood is below normal. The red blood cells are responsible for carrying oxygen to the tissues. Two general classifications of anemia are used. A Regenerative Anemia occurs when, although there are fewer red cells in the blood than normal, evidence of new blood being produced is also present. Nonregenerative Anemia occurs when little or no new blood production is noted in the blood.
Knowing that anemia itself, then, is really a symptom of some other process; the treatment of anemia will depend highly upon the cause. The tables below list the causes of both types of anemia:
Immune-Mediated Hemolytic Anemia
Immune-Mediated Thrombocytopenia
Hemobartonellosis, transmitted by fleas
Poisons and Toxins, which chemically destroy, blood cells
Blood loss/Bleeding from any source leads to loss of red cells
Trauma like being hit by a car or from a fight
Clotting Disorders which can lead to spontaneous bleeding
Ticks and Fleas that can suck out a great deal of blood
Hookworms and Whipworms that also drain away blood
Surgical bleeding
Neoplasia or tumors which can often bleed spontaneously
Ulcers of the stomach and intestine which can cause chronic bleeding
Miscellaneous causes; twisting of the spleen, heartworm disease and liver disease.
Feline leukemia and all related illnesses
Chronic infections such as dental disease or skin infections that can to inhibit blood production in the bone marrow
Chronic renal failure because the kidneys secrete a hormone that stimulates blood production
Poor nutrition where iron, copper, B-vitamins and other essential nutrients are not available to the body
Malabsorption/Maldigestion where the body cannot take in proper nutrients
Hormone secreting tumors that damage bone marrow
Poisons And Toxins that also inhibit blood production
Aplastic anemia when bone marrow stops producing blood: the cause is unknown
Myelofibrosis when bone marrow fails and scar tissue fills the marrow cavities
Leukemia and Lymphoma which may involve the bone marrow
Drugs including chemotherapy which may damage the bone marrow
Diagnosis of anemia is based on history and clinical symptoms, physical examination, complete blood counts, serum chemical analysis, urinalysis, serum iron testing and bone marrow biopsy. Remember that anemia is often part of some other disease process.
TREATMENT OF ANEMIA
Obviously, many cases of anemia will relate to some other primary disorder being diagnosed and treatment of that problem will often result in improvement of the anemia. Blood and fluid transfusions are used to provide at least temporary relief in severe and life threatening cases.
High quality diets, iron and B-vitamin supplements, anabolic hormones to stimulate blood production and general supportive care not directly related to the primary condition will all be helpful. The use of the hormone erythropoietin will cause blood production but is very expensive. Elimination of any toxic exposure or discontinuing certain drugs would make sense. Antibiotics will be used to kill blood parasites. The reader is directed again to specific treatment for specific conditions.
Polycythemia, the opposite of anemia, is an increase in the number of red blood cells in the system. Several causes are recognized. Polycythemia Vera occurs when the bone marrow becomes overproductive; the cause of this is unknown and the condition is very rare. Blood production will also be increased secondary to lower oxygen levels in the circulation. This may occur in cases of congestive heart failure, respiratory disease and secondary to certain tumors that produce hormone-like substances.
Clinical signs are often vague or minimally existent and can include enlarged blood vessels, bright red-dark red lips and exercise intolerance or weakness. Diagnosis is based on these clinical signs, blood counts, serum chemistries, urinalysis and bone marrow biopsy.
TREATMENT OF POLYCYTHEMIA
If the polycythemia is secondary to some other condition, treatment should be directed that manner. In cases of polycythemia vera, occasional blood removal (about every 2-4 months) should be performed. Experimental treatments to destroy some blood in the circulation of slow bone marrow blood production have been only minimally evaluated.
Just like human hemophiliacs, cats can suffer from problems related to blood clotting. Fortunately, these problems are relatively rare and for a good percentage of the time, are related to other illnesses, not congenital or hereditary. Like anemia, clotting disease has several classifications and subclasses. These include the following:
VASCULAR DISEASES where the strength of blood vessels is weakened and bleeding can occur. This usually occurs secondary to metabolic diseases as follows:
Vitamin C deficiency (Scurvy..rare)
Genetic collagen weakness (uncertain)
PLATELET DISORDERS which means that the tiny blood cells known as platelets which are part of the clotting process are not adequately present or do not function properly.
Platelet levels may be low due for several reasons:
Drug and Vaccine reactions
Infections of a very severe nature
Bleeding and Clotting inside the body (known as DIC)
Bone marrow failure/shut down
Platelet levels may be adequate, but they may fail to function for several reasons. While these are known to occur in the dog, the information below is more hypothetical for the cat:
Genetic defects
Certain drugs
CLOTTING FACTOR DISORDERS whereby the proteins in the blood which are part of the clotting process are, for various reasons, not functional or not even present in adequate quantities. Although few cats are affected this way, the problem, when present, is usually hereditary. Blood clotting proteins are called clotting factors. These factors react in step like fashion, similar to how one domino falls onto another until a chain is made. Failure of any one of these factors to function properly, or an absence thereof, will result in clotting failures.
A discussion of the clotting process, the genetics of various deficiencies and all the breeds that can be affected is far beyond the scope of this program. Fortunately, the genetics of these conditions makes this an extremely rare condition. Most defects are denoted as Factor XII deficiency or Factor VIII deficiency although the name Von Willebrand's Disease is used to denote a specific defect in the clotting process. Clotting factor disease is related to what we call Hemophilia in people. It is also possible for clotting disorders to occur due to a vitamin K deficiency (rare) or secondary to certain rodenticide poisonings.
Clinical symptoms will vary with the type of disease if more than one problem at a time is present and because of natural variation in severity that occurs with each different problem. Most commonly it is seen as excessive and unexplained bleeding after surgery, trauma or dental extractions. It should again be noted that multiple defects described above could be present at the same time, greatly complicating the severity of the problem.
The main clinical sign is bleeding. This can be manifest as small or larger hemorrhages or bruises on the skin, lips, gums and other moist membranes. Bleeding from gums, lips, anus or genitals may occur. Bloody or dark stools may be present. Some cats may have spontaneous nosebleeds or bloody urine. Blood clots or pockets may form under the skin. Cats may fail to clot when small cuts or cut toenails bleed. Cats may undergo "routine" surgery and bleed heavily during or after the surgery. In most cases, bleeding is sudden, unexpected and without warning. Many cats have otherwise been normal. ((Petichia))
Diagnosis is based on historical information, clinical signs, blood and platelet counts, serum chemistries, hormone analysis, X-rays, specific serologic tests and clotting tests to determine the specific defects and clotting times. Bone marrow and liver biopsy may be indicated, but consideration is always given to the potential for severe bleeding should surgery be needed.
TREATMENT OF CLOTTING DISORDERS
As always, specific treatment related to any underlying condition is the first approach to curing bleeding disease. For more severe or immediate cases, IV fluids, vitamin K, calcium injections, blood, platelet or plasma transfusions and supportive care are all necessary. B-vitamin/iron supplements to build the blood are often employed. As most cats have some other dysfunction that leads to clotting problems, most cats can live a normal life with proper treatment. However, most cats with this disorder should not be bred.
Lymphangitis is inflammation of the lymph vessels, or ducts, which connect parts of the lymphatic system including the lymph nodes. Most commonly, as lymph ducts scavenge fluid and debris that collect in body tissues, inflammation of lymphatics is caused or connected with inflammation from another source.
This would include bacterial infections, fungal infections, inflammation caused by tumors in the body, wounds and surgical sites undergoing repair and from other sites of chronic inflammation. Clinical signs include swelling, often of a limb affected, fever, loss of appetite, depression, lameness, lymph node enlargement and local nodularity. In many cases cellulitis will be present. Many times, however, there may be no specific clinical signs. Diagnosis is based on physical examination, blood counts, culture and sensitivity, biopsy and X-rays.
TREATMENT OF LYMPHANGITIS
Treatment of the primary source of infection will generally result in resolution of lymphangitis. Warm compresses, wraps and warm soaks will all help. Cortisone may help reduce swelling as well.
When some other disease process leads to damage and subsequently obstruction of lymph vessels, swelling of a part or area will then occur. Processes that commonly lead to lymphedema include surgery, including lymph node biopsy, trauma, infections, tumors and wounds. Clinical signs include a puffy swelling, often to the end of a leg (this is edema), with or without warmth and pain, enlargement of lymph nodes and occasionally a fever. Diagnosis is based on this clinical finding. There is no specific treatment other than to address the primary cause.
LYMPH NODE HYPERPLASIA (LYMPHADENITIS, LYMPHADENOPATHY)
Hyperplasia is an enlargement that occurs in one or more nodes related to inflammatory processes. Basically, the enlargement signals that something is occurring in the body or a part thereof. These include all type of bacterial infections, viral infections, rickettsial infections, fungal infections, parasitic infestations, trauma and wounds, immune-mediated disease, neoplasia including lymphoma, drugs, foreign objects in the body, inflammatory bowel disease, lymphatic obstruction or most any other stimuli. Clinical signs include node enlargement, maybe a fever, possibly pain and loss of appetite. Diagnosis as to whether reactive or cancerous enlargement is occurring is based on related physical examination and lymph node biopsy. Treatment is based on cause.
SPLENOMEGALY (ENLARGEMENT OF THE SPLEEN)
The spleen serves several functions including filtering of the blood, a storage site for red blood cells and as a center of activity for the immune system. While there are very few conditions (if any) that are considered primary diseases of the spleen, many other conditions can affect and/or damage the spleen and usually cause an increase in the size of the organ. These include: bacterial infections, histoplasmosis, toxoplasmosis, hemobartonellosis, feline leukemia, FIP, FIV, inflammatory bowel disease, congestive heart failure, many types of cancer, hemolytic disease, amyloidosis and enlargement due to certain drugs.
Often few symptoms are present, although enlargement of the abdomen may be obvious. Sometimes the spleen may twist which can cause loss of appetite, vomiting including blood, abdominal pain, increased thirst and increased urination.
Diagnosis is based on physical examination, X-rays, ultrasound and exploratory surgery. Blood count, serum chemical analysis and urinalysis and specific tests may be needed to determine the cause. In some cases, no cause will be determined. In some cases removal of the spleen and biopsy will be the only practical course. The spleen will need to be removed if twisted. ((Large Spleen))
