Article

Prevalence and clinical outcomes of the 46/1 haplotype, Janus kinase 2 mutations, and ten-eleven translocation 2 mutations in budd-chiari syndrome and their impact on thrombotic complications post Liver Transplantation

Institute of Liver Studies, King's College Hospital, National Health Service Foundation Trust, London, United Kingdom.
Liver Transplantation (Impact Factor: 3.79). 07/2012; 18(7):819-27. DOI: 10.1002/lt.23443
Source: PubMed

ABSTRACT Latent myeloproliferative disorders (MPDs) can be identified by Janus kinase 2 (JAK2) mutations in patients with idiopathic Budd-Chiari syndrome (BCS). The incidence and clinical outcomes of JAK2 mutations, novel ten-eleven translocation 2 (TET2) mutations, and the 46/1 haplotype in BCS are unknown for liver transplantation (LT). We undertook molecular studies of 66 patients presenting with BCS and correlated the results with the clinical outcomes. An overt MPD was present in 20% of the cases, and a latent MPD confirmed by the presence of a JAK2 mutation was detected in 45%. Testing for a TET2 mutation identified MPDs at the molecular level in another 7% of the subset of patients with BCS who were evaluated. The 46/1 haplotype frequency was significantly greater in BCS patients versus the general population (P < 0.001). The presence of JAK2 and TET2 mutations had no impact on 1-year survival. Thirty-six patients underwent LT, and 12 developed liver-related thrombotic complications (33%). Ten of these 12 patients required retransplantation. Retransplantation was more likely in those patients who developed liver-related thrombotic complications (P < 0.001). A JAK2 mutation was highly associated with the development of thrombotic complications after LT (P = 0.005). In conclusion, the presence of JAK2V617F predicts hepatic and extrahepatic thrombotic complications after LT. Testing for TET2 mutations can identify another 7% of idiopathic BCS patients with molecular MPDs.

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