Thrombosis and paroxysmal nocturnal hemoglobinuria clones

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired genetic disorder of
the hematopoietic stem cell. The disorder is characterized by intravascular
hemolysis with hemoglobinuria and thrombosis which can be life threatening.
Several studies have shown that approximately 1.4 % of patients with venous or
arterial thrombosis with unexplained cause have a PNH clone. This PNH clone may
have been the cause of a first thrombotic event.
The clinical chemistry laboratory of the Treant Zorggroep location Scheper has
the possibility to detect small PNH clones by flow cytometry.

The goal is to investigate wether a PNH clone could be the cause of an
unexplained thrombosis. In the population of patients with unexplained
thrombosis a PNH clone may be the cause.

The goal is to investigate whether the prevalence of PNH clones is described
correctly in literature.

All patients with unknown cause of thrombosis from the patients database of the
thrombosis service from Treant zorggroep, hospital location Scheper will be
selected.
After obtaining written consent, one extra tube of blood (4 mL) is collected
during a regular venapuncture. In this blood sample, the presence or absence of
a PNH clone is determined.
Name and address data, date of birth, diagnosis and the outcome of the
investigation is stored encrypted for all patients.
There is no control group.
The investigation relates to disease(s) from the classes vascular disorders.
The planned start date is September 1, 2016. The estimated completion date is
June 30, 2016 .

One extra tube of blood will be withdrawn during regular blood sampling. The
burden is therefore nihil. The risk of a venapuncture is negligible.