What is idiopathic thrombocytopenic purpura

What is immune thrombocytopenia (ITP)?


Immune thrombocytopenia (ITP) is an autoimmune disease affecting blood platelets (thrombocytes), which play a central role in blood clotting. Thrombocytopenia (thrombopenia for short) describes a lack of platelets in the blood.

Synonyms for immune thrombocytopenia (ITP) are: thrombocytopenic purpura, idiopathic thrombocytopenic purpura, haemorrhagic purpura, autoimmune thrombocytopenia, immune thrombocytopenic purpura. The former name Morbus Werlhof goes back to Paul Gottlieb Werlhof (1699-1767), who first described the disease in detail in 1734/35 when he was treating a 16-year-old girl who had a tendency to bleed.


The clinical picture is characterized by small skin or mucous membrane bleeding (petechiae) and bruising (hematoma). Internal bleeding is rare.

Whereas in the past a distinction was made between acute and chronic courses, a three-way division into "newly occurred", "persistent" and "chronic" is now recommended.

Frequency & causes


The frequency of immune thrombocytopenia (ITP) is 2 to 4 cases per 100,000 inhabitants, the maximum age is 50 to 55 years. 60% of the cases are chronic.

The cause is acquired autoantibodies against platelets and megakaryocytes in the bone marrow. In 80% these occur primarily (i.e. from an unknown cause or genetically determined), in 20% secondary as a result of medication or other diseases.