Thrombocytopenia: symptoms, causes and treatment

Thrombocytopenia is a health disorder characterized by bleeding; let's see how it is.

Blood, the liquid connective tissue that circulates in capillaries, veins and arteries of vertebrates, is one of the main bases of life in multicellular beings.

This fluid is responsible for allowing localized defense against infections, for participating in the transport of nutrients and oxygen to the cells, for modulating the body's thermoregulation, for transporting hormones, enzymes and other substances and, last but not least, for the processes of coagulation and healing.

In the latter field, platelets or thrombocytes are extremely important. These cytoplasmic fragments without nuclei (derived from megakaryocytes) travel to the site of any injury that is leaking blood, pile up in the fractured area of the Blood vessel forming a platelet plug and the bleeding stops. This mechanism, along with many others, prevents hemorrhagic shock from occurring.

Without the existence of platelets, humans would die after severe cuts or trauma that cause blood loss, because eventually, the heart would run out of fluid to pump and death would occur in a short time. Following this train of thought, the most natural thing to do is to ask ourselves what happens when a human being does not have adequate concentrations of platelets or thrombocytes in the blood. Here we will see what thrombocytopenia consists of.

What is thrombocytopenia?

Thrombocytopenia is a condition characterized by a low platelet count in the patient's blood.. Under normal conditions, the bloodstream carries between 140,000 and 440,000 platelet units per microliter (μl) of blood. When this value falls below 50,000 platelets per μl, bleeding can occur after relatively minor injuries, such as a scratch or superficial mechanical stressor. Below 10,000 platelets per μl, bleeding can occur even without injury and the patient's life is at risk.

In general, it is stipulated that a thrombocytopenia is such when the number of circulating thrombocytes or platelets in the blood is less than 100,000 units per μl or cubic millimeter (mm3).

One of its variants, immune thrombocytopenia, has an annual prevalence of one sick adult per 62,000-25,000 inhabitants, depending on gender. Although destruction of platelets by the immune system is not the only possible cause, this data shows that thrombocytopenia is not common in general society.

Possible causes

There are several reasons why a patient's blood platelet count may be abnormally low. Below is a summary.

1. Low platelet production

Platelets are synthesized in the bone marrow, by fragmentation at the cytoplasmic borders of megakaryocytes (the precursor cells). However, various conditions can truncate platelet production within the long bones (as well as vertebrae, ribs and other specialized bone structures).

For example, in aplastic anemia, the bone marrow stem cells are damaged and, as a result, the marrow tissue is either empty (aplastic) or contains too few cells (hypoplastic). Chemotherapy treatments, radiation therapy, exposure to toxic chemicals, the use of certain medications, viral infections, unknown factors or certain autoimmune disorders may promote this condition.

2. Elevated platelet destruction

Under normal conditions, platelets are eliminated by macrophages of the reticuloendothelial system after about 8 to 10 days in the bloodstream. In the aforementioned immune thrombocytopenia, the patient's immune system produces antibodies that attach to the membranes of platelets and megakaryocytes, signaling them. This causes the immune cells to end up destroying the platelets and their precursors, even though they do not actually pose any threat to the body.

3. Excessive accumulation of platelets in the spleen.

The spleen is an essential organ in the circulatory system, as it is responsible for filtering and destroying damaged blood cells, preventing infections (lymphocyte maturation) and storing red blood cells and platelets.

When the spleen is enlarged by certain infections, cirrhosis, cancers, anemias and some metabolic disorders, platelet retention occurs and can be pathological. In a normal situation, the spleen stores 35 to 40% of the body's platelets, but in case of splenomegaly, this value may increase to 80%.

Symptoms of thrombocytopenia

As you have seen, thrombocytopenia can occur due to a lack of platelet synthesis, a misdirected autoimmune attack or an accumulation of these cell fragments in the spleen. Beyond the etiology and the pattern that has caused the emergence of the disease, the symptomatology is similar in all cases, depending more on the platelet count than on the causative agent..

As you can imagine, the first signs of the disease will be hematological, mostly at a superficial and visible level. One of the most obvious are petechiae, small red lesions formed by the extravasation of red blood cells when a blood capillary is damaged.. They resemble rashes and may appear in clusters in areas such as the legs or abdomen.

However, it should be noted that patients with more than 50,000 platelets per milliliter of blood rarely show symptoms, while those with less than 20,000 in the same amount of fluid are prone to spontaneous bleeding. In between, we find symptoms such as a tendency to purple bruising, bleeding from the gums or nose for no apparent reason, excessive menstruation, abnormal bleeding after a cut and many other things.

On the other hand, when the platelet count is less than 10,000 platelets per microliter, sporadic internal bleeding may occur.. If these hemorrhages occur in the brain environment, the patient can quickly lose his or her life.

Treatment

If the platelet count is less than 100,000 units per microliter but close to this value, a conservative approach is taken and the patient is usually waited and monitored. Treatment begins when the platelet count is between 20,000 and 30,000 per μl or less..

As an initial "lifesaving" method in the most severe cases, platelet transfusions are performed. There are platelet concentrates that can be prescribed for thrombocytopenic patients as a prophylactic measure, especially when the platelet count is less than 10,000 units per microliter of blood. However, this addresses the immediate symptomatology, but does not treat the underlying etiologic agent.

To end a picture of thrombocytopenia, it is necessary to categorize it within the categories named above. If the problem is low platelet production due to a lack of hematopoietic stem cells (aplastic anemia), one can resort to transfusion of these precursor cell bodies. of these precursor cell bodies. However, this process is very delicate, since compatible donors must be sought and the body may reject the transplant. If rejection occurs, the patient's life can be in serious danger.

If the cause is a misdirected autoimmune attack, the drug of choice is usually prednisone, a synthetic corticosteroid usually taken orally. usually taken orally. This drug acts as an immune system suppressant, which allows the number of platelets to be restored. Although it is very effective, it puts the patient at risk for infections.

Finally, if splenomegaly is the cause, a splenectomy or removal (total or partial) of the spleen may be performed.. This operation will prevent an abnormal accumulation of platelets in the spleen, but again, this predisposes the patient to serious infections in the long term.

Summary

As you have seen, thrombocytopenia is a complex clinical entity to address, because in addition to treating the lack of platelets in the blood, it is necessary to address the underlying cause. If, for example, it is due to taking a medication, the solution is easy: stop the treatment and take another route. On the other hand, if the cause is a lack of stem cells or splenomegaly, things get quite complicated.

In any case, the sooner the condition is detected, the sooner it can be addressed and serious long-term problems can be avoided. If you have seen yourself reflected in the symptoms section, do not hesitate to see your doctor promptly. Thrombocytopenia can be treated, as long as the patient gets into the hands of a professional.