Glanzmann disease

Glanzmann Thrombasthenia (GT), also known as Glanzmann's Disease, is a rare, genetic disorder characterized by the inability of blood to clot properly. It is a type of bleeding disorder that affects the platelets, which are small blood cells essential for blood clotting. This condition is named after Eduard Glanzmann, a Swiss pediatrician who first described it in 1918.

Causes and Genetics

Glanzmann Thrombasthenia is caused by mutations in the ITGA2B and ITGB3 genes. These genes are responsible for coding the glycoprotein IIb/IIIa (αIIbβ3) complex on the surface of platelets. This complex plays a crucial role in platelet aggregation, a process essential for the formation of blood clots. Mutations in these genes lead to the improper functioning or absence of the glycoprotein IIb/IIIa complex, resulting in the symptoms associated with GT.

GT is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to be affected by the disorder. Parents of an individual with GT typically do not show symptoms of the disease but are carriers of the mutation.

Symptoms

The primary symptom of Glanzmann Thrombasthenia is an increased tendency to bleed, which can range from mild to severe. Symptoms may include:

• Prolonged bleeding from minor cuts or injuries
• Frequent nosebleeds
• Bleeding gums, especially during dental procedures
• Heavy menstrual bleeding in women
• Bruising easily
• Internal bleeding, including in the gastrointestinal tract or brain, which can be life-threatening

Diagnosis

Diagnosis of Glanzmann Thrombasthenia typically involves a combination of clinical evaluation, family history, and specialized blood tests. These tests can include:

• Platelet aggregation tests, which assess how well platelets clump together
• Flow cytometry to detect the presence or absence of the glycoprotein IIb/IIIa complex on the surface of platelets
• Genetic testing to identify mutations in the ITGA2B and ITGB3 genes

Treatment

There is no cure for Glanzmann Thrombasthenia, but the condition can be managed with treatments aimed at preventing or controlling bleeding episodes. Treatment options may include:

• Platelet transfusions, particularly for severe bleeding episodes or before surgery
• Administration of recombinant factor VIIa (rFVIIa), a protein that helps blood clot
• Antifibrinolytic agents to help stabilize clots
• Use of topical agents for minor bleeding

Patients with GT are also advised to avoid medications that can further impair platelet function, such as aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs).

Prognosis

The prognosis for individuals with Glanzmann Thrombasthenia varies. With appropriate management, most individuals can lead normal lives, although they may need to take precautions to minimize bleeding risks. Severe bleeding episodes, particularly internal bleeding, can be life-threatening and require immediate medical attention.

See Also

• Bleeding disorder
• Platelet
• Genetic disorder
• Autosomal recessive inheritance