A 70-year-old woman with a five-year history of ET with JAK2 V617F mutation treated with hydroxycarbamide for five months presented with petechiae on her limbs.
The phenotype, reported for the first time in this extended kindred, contrasts with that of an apparently unrelated family carrying the same mutation who presented with spontaneous hepatic haemorrhage and rupture, and with the manifestations in a family with the lysozyme Ile56Thr variant who presented with dermal petechiae before proceeding to fatal visceral amyloidosis.