Thrombocytopenic purpura family, Purple ... (Thrombotic thrombocytopenic purpura) - Gen ADAMTS13.

Thrombotic thrombocytopenic purpura is rare that causes blood clots in small blood vessels throughout the body disorder. These clots can cause serious medical problems if the vessels are blocked and blood flow to organs such as the brain, kidneys and the heart is restricted. The resulting complications can include neurological problems (personality changes, headaches, confusion and difficulty speaking), fever, abnormal renal function, abdominal pain and heart problems.

In people with thrombocytopenic purpura, clots in blood vessels are formed, even in the absence of injury, resulting in small bleeding under the skin surface, which manifest as ecchymosis. This disorder also causes blood erythrocytes break prematurely, resulting in hemolytic anemia, resulting in pallor, jaundice skin and mucous membranes, fatigue, and rapid heart rate.

There are two major forms of thrombotic thrombocytopenic purpura, a (non - inherited) acquired form and a familial form. The acquired form usually appears in late childhood or adulthood, manifesting affected a single episode of signs and symptoms that may recur over time. The familial form of this disorder is much rarer and usually appears in infancy or early childhood. In people with the familial form, signs and symptoms often recur regularly.

This process is due to mutations in the ADAMTS13 gene, located on the long arm of chromosome 9 (9q34), which encodes an enzyme which is involved in the normal blood clotting process. Mutations in this gene lead to a significant reduction of this enzyme. The lack of activity of the enzyme breaks the normal balance between bleeding and clotting.

They have identified more than 70 mutations in the ADAMTS13 gene cause thrombotic thrombocytopenic purpura. Most of these mutations change amino acids in the enzyme ADAMTS13. Other mutations lead to the production of an abnormally small enzyme can not function properly. Mutations in the gene cause intense ADAMTS13 reduced ADAMTS13 enzyme activity.

The familial form of thrombotic thrombocytopenic purpura is inherited as an autosomal recessive pattern, meaning that two copies of the gene in every cell must have the mutation to manifest the alteration. The parents of an individual with an autosomal recessive condition have a copy of the mutated gene, but usually show no signs and symptoms of the disease. The acquired form of thrombotic thrombocytopenic purpura is not inherited.  

Tests in IVAMI: in IVAMI perform detection of mutations associated with thrombotic thrombocytopenic purpura, by complete PCR amplification of the exons of the ADAMTS13 gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).