Thrombocytopenia

The term thrombocytopenia refers to a decrease in the number of platelets in the blood. Platelets are blood cells responsible for maintaining proper hemostatic function (coagulation), helping to prevent bleeding after an injury or spontaneously. Normally, a healthy adult has between 150,000 and 450,000 platelets per microliter of blood, although slightly lower counts may be considered physiological in some cases.

In general terms, there are three main mechanisms that can lead to thrombocytopenia:

Thrombocytopenia due to insufficient production: occurs when the bone marrow, which is responsible for producing blood cells (including platelets), does not generate a sufficient quantity.

Thrombocytopenia due to excessive destruction or utilization: platelets are removed from the blood due to abnormal destruction by the immune system or excessive consumption in clot formation.

Thrombocytopenia due to splenic sequestration: under normal conditions, a portion of platelets is stored in the spleen as a reserve. When the spleen becomes enlarged, a greater number of platelets accumulate in this organ, resulting in a lower platelet count in the bloodstream.

Symptoms

In general, mild-to-moderate decreases in platelet counts are not usually associated with an increased risk of bleeding under normal circumstances. Platelet counts below 50,000-30,000 cells/μL (or even lower) are required for symptoms to become noticeable. However, there is significant variability among patients. Some may have very low platelet counts (even <30,000 cells/μL) without showing bleeding symptoms, while others may experience significant bleeding episodes that can pose a life-threatening risk. Some symptoms that may be observed include:

• Increased tendency to bruise (bruises appearing easily and in excess).
• Petechiae: small red or purplish spots on the skin caused by subcutaneous bleeding.
• Nosebleeds or gum bleeding.
• Prolonged bleeding from cuts and wounds.
• Extremely heavy menstrual bleeding.
• Fatigue.
• Less common symptoms such as bleeding in other areas (blood in stools, urine, eyes, or even cerebral bleeding).

Causes

Depending on the origin of thrombocytopenia, the main causes to rule out when detecting a low platelet count include:

• Decreased platelet production, which may result from viral infections, severe deficiencies of certain nutrients such as vitamin B12 or folic acid. It may also be due to bone marrow disorders such as some cancers or bone marrow failure syndromes, as well as exposure to toxic agents like chemotherapy and radiotherapy.
• Increased platelet breakdown or consumption: destruction may be caused by infections, certain medications (as seen in heparin-induced thrombocytopenia), or autoimmune diseases where the immune system attacks and destroys its own platelets, such as primary immune thrombocytopenia (ITP) or lupus.
• Excessive consumption of platelets in clot formation occurs in diseases like thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (HUS).
• Excessive platelet accumulation in the spleen: occurs due to spleen enlargement, as seen in advanced liver disease.

Risk Factors

Factors that contribute to the development of thrombocytopenia include:

• Underlying conditions affecting platelet production, destruction, or accumulation.
• Excessive alcohol consumption: alcohol slows platelet production.
• Pregnancy: some pregnant women develop mild thrombocytopenia in the final stage of pregnancy.
• Medications and medical procedures that can destroy platelets, such as heparin, quinine, blood transfusions, or bypass surgery.

Complications

Most of the time, initial bleeding episodes due to low platelet counts are limited to the skin and mucous membranes (bruising, nosebleeds, or oral bleeding). However, in cases of severe and prolonged thrombocytopenia, bleeding may occur in other organs, which can be serious.

Prevention

To reduce the risk of bleeding when thrombocytopenia is present, the following measures may be considered:

• Avoiding or reducing the intake of certain medications, such as aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and dexketoprofen, as they affect platelet function.
• Avoiding or minimizing activities with a risk of trauma and contact sports that could cause injuries.
• Moderating alcohol consumption.

Which Doctor Treats Thrombocytopenia?

Hematologists are the specialists responsible for evaluating and treating thrombocytopenia.