Positive-DAT and autoimmune manifestations in patients with JAK2V617F mutation

Abstract

Objective: Myeloproliferative neoplasms (MPN) are occasionally associated with autoimmune manifestations. The prevalence of positive direct antiglobulin test (DAT) in patients with JAK2V617F mutation is not yet known. Methods: We conducted a cohort study of all consecutive patients with JAK2V617F mutation who underwent DAT at presentation from 2010 to 2022. We also looked for the prevalence of autoimmune diseases (AIDs) and relation to thrombosis. Results: Fifty nine patients formed the cohort, 22 females and 37 males, with a mean age of 65 years. The median follow-up time was 90 months. A positive-DAT was found in 6 to 7% of essential thrombocythemia (ET) and polycythemia vera (PV) patients, 60% of primary myelofibrosis (PMF) patients and 50% of myelodysplasia/myeloproliferation (MDS/MPN) patients with or without anemia. Autoimmune manifestations were present in 13% of patients with PV and 50% of those with MDS/MPN features. Overall, 25% of patients had autoimmune phenomena including the 15% with positive-DAT. Conclusion: In patients with JAK2V617F mutation, those with PMF and MDS/MPN subtypes are most likely to display a positive-DAT results and autoimmune manifestations (≥ 50%). Patients with PV and ET are less likely to exhibit autoimmune manifestations (≤ 10%). No correlation with the occurrence of thrombosis was seen.