Can platelet count be controlled with ticagrelor in patients with essential thrombocythaemia? A case series.

BACKGROUND: Essential thrombocythaemia (ET) is defined as a myeloproliferative neoplasm with a tendency to haemorrhage and thrombosis. Acute coronary thrombosis can be observed in 1 out of 10 patients. The management of ET patients with acute coronary syndrome (ACS) is a complex clinical condition that requires close follow-up.

CASE SUMMARY: Case-1 : a 52-year-old female patient with a diagnosis of ET with Janus kinase (JAK)--2 mutation, despite using cytoreductive agents, platelet counts could not be controlled. Platelet counts started to follow a normal course with the ticagrelor treatment given after ACS. Case-2 : a 49-year-old female patient who was given ticagrelor treatment after ACS was found to have JAK-2+ ET. The patient whose platelet count returned to normal after ticagrelor treatment was using a cytoreductive agent before the index event. Case-3 : a 54-year-old female patient with ET without any genetic mutation. In the patient whose platelet count did not decrease despite ticagrelor treatment and cytoreductive agents given after ACS, platelet counts returned to normal with interferon therapy.

DISCUSSION: Platelet counts returned to the normal range with ticagrelor treatment given after ACS in patients with JAK+ ET. Monitoring platelet reduction in JAK+ patients with P2Y12 inhibition is thought to be important for new treatment options.