Journal des troubles sanguins et de la transfusion

Abstrait

Detection of Subclinical/Minor PNH Clone(S) in Patients with Thrombotic Events

Ioanna Anastasopoulou, Paraskevi Kotsis, Stilliani Kokori, George Lallas1, Sofia Gkotsi, Olga Katsarou, Konstantinos Konstantopoulos

Background: Paroxysmal nocturnal hemoglobinuria is a rare acquired disorder of a pluripotent hematopoietic stem cell, caused by a PIG-A gene somatic mutation. Thrombosis occurs in 40% of PNH patients and consists a main cause of morbidity. More than one-third of thrombotic episodes are located in hepatic veins, the inferior vena cava and cerebral veins.

Study objective: To evaluate the presence and role of PNH subclinical/minor clone(s) in idiopathic VTE patients, with no known congenital or acquired thrombophilia.

Study design: 181 patients having experienced idiopathic thrombosis and 100 healthy controls were screened for PNH clone(s) presence by flow cytometry. Testing was performed on white blood cells using FLAER and on red blood cells using CD59. The study was focused on the presence of minor clone(s), according to cut-off values raised from the healthy population.

Results: Ten out of 181 patients were revealed with a small PNH clone in both cell lines (WBCs and RBCs). The presence of a minor clone was not found to be associated with thrombosis prognosis or recurrence. Conclusions: PNH screening should be performed (especially) in young patients with unexplained thrombosis or thrombosis in unusual sites. According to our data, it is not concluded that the parameters tested are associated with disease prognosis or VTE recurrence. In certain populations, a higher percentage of minor clone(s) was observed; re-examination and systematic follow-up might be useful for specific individuals cases. Further studies with a larger number of individuals may be needed.

Conclusion: Paroxysmal nocturnal hemoglobinuria is a disorder in patients more than one-third of thrombotic episodes is located in hepatic veins, the inferior vena cava and cerebral veins. Mainly it is focussed under the PNH clones in thrombotic patients. Majorly the young individuals are experienced arterial thrombosis and splanchnic vein thrombosis.