Multiple aortic thrombi in essential thrombocythaemia

A 77-year-old man with essential thrombocythaemia (ET) and hypertension presented with dyspnoea and fever. He had a Janus kinase 2 (JAK2) V617F mutation with an allele burden of 56.88%. He was taking aspirin 100 mg and hydroxycarbamide 500 mg daily, but his adherence had been poor during the previous week. His full blood count revealed a white blood cell count of 199.7 9 10/l (promyelocytes 1.0%, myelocytes 12.5%, metamyelocytes 6.5%, band forms 23.5%, segmented neutrophils 47.5%, eosinophils 5.0%, basophils 1.0%, monocytes 1.5% and lymphocytes 1.5%), haemoglobin concentration of 105 g/l and platelet count of 974 9 10/l. Fluorescence in situ hybridisation (FISH) for breakpoint cluster region-Abelson murine leukaemia viral oncogene homologue 1 (BCR-ABL1) on interphases of peripheral blood neutrophils was negative. Blood culture showed bacterial growth, identified as Staphylococcus schleiferi. Computed tomography (CT) for the evaluation of dyspnoea and fever showed multiple thrombi in the descending and abdominal aorta (images, left coronal view and right sagittal view). A transthoracic echocardiogram showed no vegetations or intracardiac thrombus. A bone marrow biopsy was consistent with ET without secondary myelofibrosis or acute leukaemia. Thus, treatment with aspirin was resumed, hydroxycarbamide was increased to 2 g daily, and heparinisation and cefazolin treatment were initiated. Thrombi had disappeared on repeat CT 1 month later.