Primary Immune Thrombocytopenia and Essential Thrombocythemia: So Different and yet Somehow Similar—Cases Series and a Review of the Literature

Abstract

This article collects several published cases in which immune thrombocytopenic purpura (ITP) is followed by essential thrombocythemia (ET) and vice versa. This surprising clinical condition is possible, but very rare and difficult to diagnose and manage. We have made an attempt to analyse the possible causes of the sequential appearance of ITP and ET taking into consideration the following: alteration of the thrombopoietin (TPO) receptor, the role of autoimmunity and inflammation, and cytokine modulation. A better understanding of these interactions may provide opportunities to determine predisposing factors and aid in finding new treatment modalities both for ITP and ET patients.

A randomized, double‐blind, comparative study of the pharmacodynamics and pharmacokinetics of GP40141 (romiplostim biosimilar) and reference romiplostim in healthy male volunteers

“…Idiopathic (immune) thrombocytopenic purpura (ITP) is an autoimmune condition characterized by isolated thrombocytopenia (<100 × 10 9 /L) that is not associated with other known causes 1 . The incidence of ITP in the population is 1.9–6.4 cases per 100 000 children and 3.3 per 100 000 adults 2,3 …”

“…1 The incidence of ITP in the population is 1.9-6.4 cases per 100 000 children and 3.3 per 100 000 adults. 2,3 The etiology of this condition is still uncertain, but there are some trigger factors that enhance the probability of contracting ITP.…”

“… 1 The incidence of ITP in the population is 1.9–6.4 cases per 100 000 children and 3.3 per 100 000 adults. 2 , 3 …”

Excluding JAK2 V617F mutation analysis from the primary immune thrombocytopenia ‘diagnosis of exclusion’

“…Acknowledging that ITP has been sporadically reported in cases of essential thrombocythemia, another type of MPN characterized by increased platelets [4], this brief audit suggests that routine screening for MPN driver mutations in the molecular diagnostic work up of ITP (and isolated thrombocytopenia) is unwarranted where no clinical, haematological or morphological features of an MPN are present.…”

Hematologic complications after kidney and pancreas transplant in a patient with chronic myeloid leukemia

“…There have been case reports of ITP in patients with polycythemia vera and essential thrombocytosis. 20,21 Also, there are several reports of primary ITP later transforming to CML. 22,23 However, the diagnosis of ITP occurring several years later in a patient with established CML is extremely rare.…”