A Rare Case of Triple-Negative Essential Thrombocythemia in a Young Postsplenectomy Patient: A Diagnostic Challenge

Triple-Negativity Identifies a Subgroup of Patients with Better Overall Survival in Essential Thrombocythemia

Essential thrombocythemia, as defined by the WHO in 2016, is a Philadelphia-negative chronic myeloproliferative neoplasm showing a better prognosis than polycythemia vera and myelofibrosis. In a variable percentage, patients with essential thrombocythemia show none of the known driver-gene mutations that may occur on JAK2, CALR, and MPL genes. Such patients are classified as triple-negative and their clinical features and prognosis have not been described with precision yet. In this study, we evaluated some of the characteristics of this population by comparing them with those of patients with driver-gene mutated ET. Data from 266 consecutive essential thrombocythemia patients were analysed. Triple-negative patients had a significantly lower symptom load and a lower frequency of splenomegaly at diagnosis. The results show that the rate of thrombosis was equal in the two subgroups. Overall survival was slightly better in the triple-negative group of patients.

Essential Thrombocythemia Due to Janus Kinase 2 Mutation Unmasked After Splenectomy

Reactive thrombocytosis after splenectomy is common and often self-limiting. However, thrombocytosis can be multifactorial, especially extreme thrombocytosis (platelet count > 100 x 10⁴/cubic mm). It can lead to thrombotic or hemorrhagic complications. Hence, in patients with rising platelet count after splenectomy, detailed evaluation may be required to rule out other causes of thrombocytosis, such as infection, iron deficiency, and myeloproliferative disorders. Timely treatment of patients with thrombocytosis can prevent the development of life-threatening complications. The index case highlights the importance of regular follow-up of the patients after splenectomy to detect thrombocytosis and suspect other causes if the spleen was diseased or the platelet count fails to resolve spontaneously.