Rebound of platelet count in a patient with type 2 calreticulin-mutant essential thrombocythemia in the postpartum period: A case report

Abstract

Introduction: Essential thrombocythemia (ET) is an uncommon myeloproliferative neoplasm. It is more common in females; 20% of them are below 40 years old. The optimal management of ET during pregnancy and postpartum periods is still not well established. Patient concern: We report a case of a young lady with type 2 calreticulin-mutant ET who developed a marked rebound in her platelet count (reaching 2030 × 103/mL) 2 weeks after premature delivery of her baby (24th week of gestation). She was on Pegylated Interferon alfa 2-a during pregnancy (her platelet was around 500 × 103/mL during the second trimester), but she had stopped it on her own from the 20th week of gestation. Diagnosis: Postpartum rebound of platelet count due to medication non-compliance. Intervention and outcome: We resumed her regular Pegylated Interferon, and subsequently, her platelet count reduced dramatically within 4 weeks to an acceptable level (684 × 103 /mL). Conclusion: The guideline is still not well-established regarding the optimal approach for postpartum rebound of platelet count in patients with ET. It is still unclear if the platelet count will fall spontaneously without intervention after the rebound phase. Further research is required to establish the optimal management of ET during the postpartum phase. This case emphasizes the importance of platelet count follow-up during the postpartum period and outlines our management approach in such cases. Abbreviations: CALR = calreticulin, ET = essential thrombocythemia, IFN = interferon, MPL = myeloproliferative leukemia, MPN = myeloproliferative neoplasm.