Thrombocytopenia is a condition in which platelets, also known as thrombocytes, are unusually low in the blood. It’s the most frequent coagulation condition in ICU patients, with 20% of medical patients and a third of surgical patients having it.
Mild to severe bleeding can occur when your blood contains too few platelets. Internal bleeding, bleeding beneath your skin, and bleeding from the surface of your skin are all possibilities (external bleeding).
In adults, a typical platelet count is between 150,000 and 450,000 platelets per microliter of blood. Platelet counts of less than 150,000 platelets per microliter are abnormally low. Thrombocytopenia is a condition in which your blood platelet count falls below normal. However, significant bleeding does not occur until the platelet count drops to below 10,000 or 20,000 platelets per microliter. When the platelet count is fewer than 50,000 per microliter, mild bleeding can occur.
Thrombocytopenia Causes
Thrombocytopenia(a low platelet count) can be caused by a variety of reasons. The disease can either be hereditary or acquired. “Inherited” means your parents passed down the disease gene to you. The term “acquired” refers to a condition that you acquire rather than being born with. The cause of thrombocytopenia isn’t always known.
In general, a low platelet count occurs because:
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The body’s bone marrow doesn’t make enough platelets.
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The bone marrow makes enough platelets, but the body destroys them or uses them up.
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The spleen holds on to too many platelets.
A low platelet count can also be caused by a combination of the preceding reasons.
1. The Body’s Bone Marrow Doesn’t Make Enough Platelets
The sponge-like tissue inside the bones is called bone marrow. It contains stem cells that mature into red, white, and platelet blood cells. Damaged stem cells are unable to develop into healthy blood cells.
Stem cells can be harmed by a variety of circumstances and factors.
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Cancer: Cancers that affect the bone marrow and kill blood stem cells, such as leukaemia and lymphoma, can harm the bone marrow. Radiation and chemotherapy are two cancer treatments that kill stem cells.
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Aplastic Anemia: Aplastic anaemia is an uncommon and deadly blood condition that occurs when the bone marrow stops producing enough new blood cells. The quantity of platelets in your blood is reduced as a result of this.
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Toxic Chemicals: Toxic substances, such as pesticides, arsenic, and benzene, can cause platelet formation to slow.
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Medicines: Platelet production can be slowed by several medications, such as diuretics and chloramphenicol. In the United States, chloramphenicol (an antibiotic) is rarely used. Platelet function can also be harmed by over-the-counter medications like aspirin and ibuprofen.
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Alcohol: Platelet generation is also slowed by alcohol. Heavy drinkers often have a temporary decline in platelet count, especially if they consume foods that are poor in iron, vitamin B12, or folate.
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Viruses: For a short time, chickenpox, mumps, rubella, Epstein-Barr virus, or parvovirus can lower your platelet count. Thrombocytopenia is a common complication of AIDS.
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Genetic Conditions: Low platelet counts in the blood can be caused by a variety of hereditary disorders. Wiskott-Aldrich and May-Hegglin syndromes are two examples.
2. The Body Destroys Its Own Platelets
Even if the bone marrow produces adequate platelets, a low platelet count might exist. Autoimmune illnesses, some drugs, infections, surgery, pregnancy, and several illnesses that cause excessive blood clotting might cause the body to destroy its own platelets.
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Autoimmune Diseases: When the immune system mistakenly targets healthy cells in the body, autoimmune disorders develop. Thrombocytopenia can arise when an autoimmune disease kills the body’s platelets.
Immune thrombocytopenia is an example of this sort of autoimmune illness (ITP). ITP is a clotting condition in which the blood fails to clot properly. Most cases of ITP are thought to be caused by an autoimmune response. Your immune system normally aids your body in fighting infections and disorders. Your immune system, on the other hand, assaults and destroys your own platelets if you have ITP. It’s unclear why this occurs. (ITP can also happen if your immune system targets your platelet-producing bone marrow.)
Lupus and rheumatoid arthritis are two more autoimmune disorders that damage platelets.
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Medicines: A drug reaction can lead your body to become confused and kill its platelets. Quinine, antibiotics containing sulfa, and various seizure medications, such as Dilantin, vancomycin, and rifampin, are all examples of medicines that can induce this. (Quinine is a mineral that can be found in tonic water and nutritional supplements.)
Heparin is a blood thinner that is widely prescribed to avoid blood clots. However, the drug may cause blood clots and thrombocytopenia as a result of an immunological reaction. Heparin-induced thrombocytopenia is the name for this condition (HIT). Outside of a hospital, HIT is uncommon.
The immune system of the body assaults a compound generated by heparin and a protein on the surface of platelets in HIT. The platelets are activated as a result of the attack, and they begin to form blood clots. Blood clots can grow deep in the legs or break loose and migrate to the lungs (deep vein thrombosis) (pulmonary embolism).
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Infection: Blood poisoning from a widespread bacterial infection might result in a low platelet count. A virus can also produce a low platelet count, such as mononucleosis or cytomegalovirus.
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Surgery: When platelets flow through artificial heart valves, blood vessel grafts, or machinery and tubing used for blood transfusions or bypass operations, they can be destroyed.
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Pregnancy: When a woman is close to giving birth, about 5% of pregnant women have moderate thrombocytopenia. The specific cause has yet to be determined.
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Rare and Serious Conditions That Cause Blood Clots: A low platelet count can be caused by a variety of rare and serious illnesses. Thrombotic thrombocytopenic purpura (TTP) and disseminated intravascular coagulation are two instances (DIC).
TTP is a blood disorder that affects a small number of people. It produces blood clots in small blood vessels throughout the body, including those in the brain, kidneys, and heart.
DIC is an uncommon condition that can occur as a result of pregnancy, severe infections, or severe trauma. Throughout the body, tiny blood clots form unexpectedly.
The blood clots in both cases deplete the platelets in the blood.
3. The Spleen Holds on to too Many Platelets
The spleen usually stores one-third of the body’s platelets. The spleen will hold on to too many platelets if it is big. This suggests that there will be insufficient platelets in the blood.
Cancer or severe liver disease, such as cirrhosis, can cause an enlarged spleen. Cirrhosis is a scarring condition that affects the liver. This makes it impossible for it to function properly.
A bone marrow disorder like myelofibrosis could cause an enlarged spleen. The bone marrow is damaged and unable to produce blood cells in this disorder.
Thrombocytopenia Signs and Symptoms
The main indications and symptoms of thrombocytopenia include mild to severe bleeding. Internal bleeding, bleeding beneath your skin, and bleeding from the surface of your skin are all possibilities (external bleeding).
Symptoms and signs might arise suddenly or gradually. Mild thrombocytopenia frequently has no symptoms or indicators. It’s frequently discovered through a regular blood test.
Thrombocytopenia can cause bleeding in practically any organ of the body if it is severe enough. Bleeding is a medical emergency that must be handled immediately.
The first sign of a low platelet count is usually external bleeding. Purpura or petechiae can be caused by external bleeding. Purpura is bruises that are purple, brown, or red in colour. This type of bruising can happen quickly and frequently. Petechiae are little red or purple dots that appear on the skin.
External bleeding might also manifest itself in the following ways:
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Bleeding that lasts for a long time, even from minor cuts
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Bleeding or leaking from the mouth or nose, particularly nosebleeds or bleeding during tooth brushing
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Vaginal bleeding that isn’t normal (especially heavy menstrual flow)
A lot of bleeding after surgery or dental treatments could potentially indicate a problem with bleeding.
Internal haemorrhage (heavy bleeding into the intestines or brain) is dangerous and can be fatal. Signs and symptoms include:
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Blood in the urine or stool, as well as rectum bleeding.
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The blood in the stool can be scarlet or dark and tarry in colour. (Iron supplementation can also result in dark, tarry stools.)
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Other neurological problems such as headaches.
Idiopathic Thrombocytopenic Purpura
Idiopathic thrombocytopenic purpura is an immunological illness characterised by abnormal blood clotting. Immune thrombocytopenic Purpura is the more prevalent name for this illness (ITP).
ITP might result in a lot of bruising and bleeding. ITP is caused by an abnormally low level of platelets, or thrombocytes, in the blood.
Types:
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Acute (short-term) and chronic ITP are the two basic kinds of ITP (long term).
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The most prevalent form of ITP in children is acute ITP. It normally only lasts around six months.
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ITP that is chronic lasts six months or more. Adults are the most usually impacted, however, teenagers and younger children can also be impacted.
Causes:
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Antibodies against platelets are produced by the immune system in ITP. The spleen marks these platelets for destruction and evacuation, lowering the platelet count. The immune system also appears to interfere with cells that are responsible for normal platelet formation, resulting in a reduction in platelet count in the blood.
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Following a virus, ITP frequently develops aggressively in youngsters. ITP commonly develops over time in adults.
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ITP can be classed as either primary (occurs on its own) or secondary (occurs in conjunction with another disorder). Secondary triggers include autoimmune illnesses, chronic infections, medicines, pregnancy, and some malignancies.
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ITP is not a contagious disease.
Symptoms:
Most common symptoms include spontaneous nosebleeds, bruises readily,pinpoint-sized petechiae, often on the lower thighs, bleeding gums (for example, during dental work), urine with blood in it, faeces with blood, menstruation that is very heavy, cuts that bleed for a long time etc.
Heparin Induced Thrombocytopenia
Heparin induced thrombocytopenia (HIT) is the development of thrombocytopenia (low platelet count) as a result of the use of anticoagulants such as heparin. Because platelets emit microparticles that activate thrombin, HIT increases the risk of thrombosis (the abnormal formation of blood clots inside a blood artery). Heparin-induced thrombocytopenia and thrombosis is the name given to the condition when thrombosis is discovered (HITT).
Symptoms:
Enlargement or extension of a previously diagnosed blood clot, or the development of a new blood clot elsewhere in the body, are the most prevalent symptoms of HIT. This can happen in the form of clots in the arteries or veins, resulting in arterial or venous thrombosis.
Stroke, myocardial infarction (“heart attack”), and acute limb ischemia are all examples of arterial thrombosis. Venous thrombosis can develop in the leg or arm as a deep vein thrombosis (DVT) or in the lung as a pulmonary embolism (PE); the latter commonly starts in the leg and travels to the lung.
When people are given heparin via intravenous infusion, they may have a slew of symptoms called a “systemic response.” Fever, chills, elevated blood pressure, a fast heart rate, shortness of breath, and chest pain are some of the symptoms. About a fifth of patients with HIT experience this. Others may develop a rash with red dots on their skin.