How is Glanzmanns thrombasthenia diagnosed?

Glanzmann's thrombasthenia is a rare inherited bleeding disorder characterized by the inability of platelets to properly aggregate and form blood clots. It is caused by mutations in the genes encoding the glycoprotein IIb/IIIa complex, which is essential for platelet aggregation. The diagnosis of Glanzmann's thrombasthenia involves a combination of clinical evaluation, laboratory tests, and genetic analysis.

Clinical Evaluation

The first step in diagnosing Glanzmann's thrombasthenia is a thorough clinical evaluation. The healthcare provider will review the patient's medical history, including any bleeding episodes or family history of bleeding disorders. They will also perform a physical examination to assess for any signs of bleeding, such as petechiae (small red or purple spots on the skin), ecchymosis (bruising), or prolonged bleeding from minor cuts or injuries.

Laboratory Tests

Laboratory tests play a crucial role in confirming the diagnosis of Glanzmann's thrombasthenia. The following tests are commonly performed:

Platelet Function Tests

Platelet function tests assess the ability of platelets to aggregate and form blood clots. The most commonly used test is the platelet aggregation test, which measures the response of platelets to various agonists (substances that induce platelet activation). In Glanzmann's thrombasthenia, platelets fail to aggregate in response to agonists that normally cause aggregation.

Bleeding Time

Bleeding time measures the time it takes for bleeding to stop after a standardized skin incision. In Glanzmann's thrombasthenia, bleeding time is typically prolonged due to the impaired platelet function.

Complete Blood Count (CBC)

A complete blood count provides information about the number and characteristics of blood cells. In Glanzmann's thrombasthenia, the platelet count is usually normal, but the platelets may appear larger than normal under a microscope.

Genetic Analysis

Genetic analysis is the definitive method for diagnosing Glanzmann's thrombasthenia and identifying the specific mutations responsible for the disorder. This analysis involves sequencing the genes encoding the glycoprotein IIb/IIIa complex (ITGA2B and ITGB3) to identify any mutations or abnormalities.

It is important to note that Glanzmann's thrombasthenia is a genetic disorder, and therefore, genetic testing is crucial not only for diagnosis but also for identifying carriers within families. Genetic counseling may be recommended for individuals with Glanzmann's thrombasthenia or those who are carriers to understand the inheritance pattern and the risk of passing the condition to their children.

Differential Diagnosis

Other platelet function disorders and bleeding disorders may present with similar symptoms to Glanzmann's thrombasthenia. Therefore, it is important to consider other potential diagnoses and rule them out through appropriate testing. Some conditions that may be considered in the differential diagnosis include:

• Bernard-Soulier syndrome


• Storage pool disorders


• von Willebrand disease


• Platelet-type von Willebrand disease


• Acquired platelet function defects

Overall, the diagnosis of Glanzmann's thrombasthenia involves a combination of clinical evaluation, laboratory tests to assess platelet function, and genetic analysis to identify specific mutations. Early and accurate diagnosis is crucial for appropriate management and treatment of individuals with Glanzmann's thrombasthenia.