What is immune thrombocytopaenia?1

Immune thrombocytopaenia (or ITP) is by definition an autoimmune disease characterised by a low platelet (thrombocyte) count (< 100 x 109/l).
ITP is characterised by low production of platelets. There is also increased degradation of platelets by the immune system of the body. Platelet deficiency (thrombocyte deficiency) may cause haemorrhages.

In 1735, the disease was first described by Paul Gottlieb Werlhof, a court doctor working in Hannover. That is why ITP is also called “Werlhof’s Disease” (Morbus Werlhof). ITP affects all age groups, both children and adults.

The incidence rate (or number of new diagnoses/per year) of ITP in men and women differs with age. Between the ages of 6 and 60, women are the most affected, under 5 years of age and over 60 years of age, it is more common in men.
Around 2 to 4 in 100,000 adults are diagnosed with ITP annually. ITP is a rare disease that meets the criteria for an orphan disease (number of patients < 5/10,000 people).


Causes of ITP1

ITP is characterised by increased degradation of platelets in the spleen, by antibodies against the platelets.
These antibodies are also called autoantibodies. In addition, the autoantibodies may prevent the formation of new platelets in the bone marrow.

Together, these two phenomena lead to a reduced number of platelets in the blood (thrombocytopaenia). If you have ITP without an identifiable cause, this is called “primary ITP”.
In recent years, multiple processes have been shown to underlie this disease. Different mechanisms are involved in each patient. That explains why patients can have different symptoms and can also respond differently to treatment.
We refer to a secondary form if there is a clear cause of the disease, for example due to the intake of certain medicines, after an infectious disease or after vaccination.
80% of immune thrombocytopaenia cases have a primary origin and 20% a secondary origin. ITP is not hereditary or contagious; you cannot give it to your children, family or friends.



Symptoms of ITP can vary greatly from person to person. Many ITP patients have no visible symptoms. This is why in some cases the platelet deficiency is discovered “by chance” during a routine blood analysis.

Other patients may experience bleeding symptoms such as:

  • Bleeding of mucous membranes (e.g. frequent bleeding of nose or gums)
  • Petechiae: small point-shaped bleedings in the skin (like a flea bite), often on the arms or legs, but also on oral mucous membranes
  • Tendency to easily develop “bruises” or haematomas, even after mild trauma
  • Unusually long bleeding of small injuries
  • Particularly heavy monthly periods





  1. Onkopedia Leitlinie ITP [Directive Onkopedia sur le PTI], https://www.onkopedia.com/de/onkopedia/guidelines/ immunthrombozytopenie-itp/@@guideline/html/index.html (last consulted on 31.03.2020).

Ask Speakers