How is thrombocytopenia diagnosed?

Thrombocytopenia is diagnosed through various tests and examinations, including:

1. Complete Blood Count (CBC): A CBC measures the levels of different blood cells, including platelets. A low platelet count (thrombocytopenia) is typically defined as a platelet count below 150,000 platelets per microliter of blood.

2. Blood Smear: A blood smear involves spreading a thin layer of blood on a slide and examining it under a microscope. This allows the healthcare professional to assess the size, shape, and appearance of platelets and other blood cells. Abnormalities in platelet morphology may suggest specific causes of thrombocytopenia.

3. Platelet Function Tests: These tests evaluate the functionality and activity of platelets. They may include tests such as platelet aggregation studies, bleeding time, and clot retraction tests. These tests can help identify disorders affecting platelet function, which can contribute to thrombocytopenia.

4. Bone Marrow Aspiration and Biopsy: In some cases, a bone marrow aspiration and biopsy may be recommended to examine the bone marrow, where platelets are produced. This procedure involves using a needle to extract a small sample of bone marrow for analysis. It can help determine the underlying cause of thrombocytopenia, such as bone marrow disorders or infections.

5. Additional Tests: Depending on the suspected cause of thrombocytopenia, additional tests may be performed. These may include:

- Blood clotting tests, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT), to assess the overall coagulation status.

- Tests for infections, such as viral or bacterial cultures, to identify potential infectious causes of thrombocytopenia.

- Autoimmune tests, such as antinuclear antibody (ANA) or direct antiglobulin test (DAT), to evaluate for autoimmune disorders that may affect platelets.

- Genetic tests, such as chromosome analysis or gene mutation studies, to identify inherited or genetic causes of thrombocytopenia.

The diagnosis of thrombocytopenia involves a combination of these tests, along with a detailed medical history and physical examination, to determine the underlying cause and appropriate management.