Introduction

1. Successful outcome of a pregnancy with Essential Thrombocythaemia A case report and Literature review Nausheen A, Syed A. Gloucestershire Royal Hospital Gloucester ,UK. OPTIONALLOGO HERE OPTIONALLOGO HERE Case Report Discussion Introduction Conclusions Essential thrombocythaemia (ET) is a rare chronic myeloproliferative disorder with an incidence of 1.5/100,00.1 It is characterized by increase platelet count ,hyperplasia of megakaryocytes and haemorrhagic or thrombotic tendency. Most patients are asymptomatic. However, those with symptoms can present with microvascular symptoms(headache, lightheadedness, parasthesias) or thrombotic and haemorrhagic disturbance. Rarely it can also transform to myelofibrosis or acute leukaemia.2 Pregnancy in ET patients has more risk of complications ET has been associated with miscarriage, intrauterine death, preeclampsia and placental abruption.3 We present a case of ET in a pregnant woman with a positive outcome. The case assess the effect of aspirin and heparin in the management of this condition in pregnancy and increases awareness of this condition and its adverse implications for pregnancy. A 34 year old Asian woman booked at 10 weeks in our antenatal clinic. She was in her fourth pregnancy. The first two pregnancies were uneventful with delivery of term babies. She had an unexplained intrauterine death in her third pregnancy at 30 weeks. She was diagnosed with ET the year following that pregnancy, the diagnosis was made incidentally. She was commenced on aspirin 75mg OD from the time. Platelet levels at the time of booking in this pregnancy was 593. Growth scans were requested at 28 and 34 weeks due to increased risk of perinatal complications .Haematology advice was sought. Aspirin was discontinued at 36 weeks. LMWH was commenced on the advice of the haematologist Induction of labour was offered at 38 weeks. Labour and delivery were uneventful. LMWH was continued postnatally for 6 weeks. Essential thrombocythaemia is more common in women, 15% to 20% of patients are young, therefore pregnancies are not uncommon.4 A number of case reports and case series are available in the literature. In several large case series, the live birth rate has been reported as 51%-74% .Maternal complication rate is 8%-11% with spontaneous miscarriage being the commonest 3,5 Second and third trimester complications are less frequent.6 Relationship of risk factors with pregnancy outcome has been extensively reviewed. JAK2(V617F) mutation was discovered in 50%-60% of ET patients in 2005 7 and it gives a typical phenotype to the patients.8This mutation has been considered a risk factor for pregnant patients with ET 3 .In another retrospective study, pregnancy outcome was not effected by platelet count, leukocyte count or JAK2(V617F) mutation.9 The management of ET in pregnancy is controversial. Therapeutic options include: no treatment, treatment with aspirin or with antiplatelet agents like interferon or angrelide. Low dose aspirin is safe in pregnancy. In a study comparing no treatment versus treatment with Aspirin, a salutary role for aspirin therapy was established 9 . Another study shows that Aspirin reduces obstetric complications by reducing micro vascular disturbances 10,while a higher live birth rate was seen with interferon a as compared to aspirin treatment 3. The role of cytoreductive agents like hydroxyurea and anagrelide in the management of non-pregnant patients with ET is well established. Successful pregnancies have been reported in literature 3. However because of potential fetal complications they are not considered safe in pregnancy and should be discontinued 3-6 months before pregnancy11 . Conflicting results in literature are not helpful in deciding the best management option. The guidelines from the BCSH (British Committee for Standards in Haematology) recommends that patients should be stratified according to risk factors for complications in pregnancy. The risk factors include previous venous or arterial thrombosis, previous hemorrhage due to ET or previous pregnancy complications (e.g. intrauterine death, miscarriage, preeclampsia, abruption) .Aspirin is recommended in all pregnant patients throughout pregnancy. Those with risk factors should be considered for cytoreductive therapy and INF-a is safest among them 11. On going assessment for thrombotic risk is recommended. Fetal growth should be monitored with regular growth scans. The guidelines also recommend thromboprophylaxis with LMWH for 6 weeks postnatally for all patients. There is a need for a large prospective clinical trial and research in basic pathology which will help us to learn more about this disorder. UKOSS is currently collecting data on patients with myeloproliferative disorders in pregnancy. This will add to our present knowledge of this condition. References 1. Johansson P . Epidemiology of the Myeloproliferative disorders polycythaemia vera and essential thrombocythaemia. Semin Thromb Hemost 2006 April 32(3) 171-3. 2. Tefferi A. Polycythaaemia vera and Essential thrombocythaemia:2012 update on diagnosis, risk stratification and management : Am J Hematol.2012 Mar;87(3):285-93. 3. Melillo L, Teighi A, Candoni A, Radaelli F, Ciancia R, Specchia G, Martino B, Scalzulli PR, Latagliata R, palmieri F, Usala E, Valente D, Valvano MR, Cedrone M, Comitini G, Martinelli V, Cascavilla N, Gugliotta L.Outcome of 122 pregnancies in essential thrombocythaemia patients: a case report from the Italian registry.Am J Hematol 2009;84:636-40 4.Elliott MA, Tefferi A .2003.Thrombocythaemia and pregnancy.Best practice and research.Clinical haematology 16;227-242. 5. Cincotta R, Higgins JR, Tipett C, Gallery E, North R, McMahon LP, Brennecke SP.Management of essential thrombocythaemia during pregnancy.Aust N Z J Obstet Gynaecol. 2000 Feb;40(1) : 33-7. 6. Wright CA, Tefferi A. A single institutional experience with 43 pregnancies in essential thrombocuthaemia. Eur J Haematol.2001 Mar; 66 (3); 152-9 7. Kralovices R, Passamonti F, Buser As, Teo Ss, Tiedt R, Passweg JR, Tichelli A, Cazzalo M,Skoda RC.A gain of function mutation of JAK2 in myeloproliferative disordets.N Engl J Med 2005;352:1779-90. 8. Campbell PJ, Scott LM, Buck G,Wheatley K, East CL, Marsden JT,Duffy a, Boyd EM, Bench AJ,Scott MA, Vassilliou GS,Milligan DW, Smith SR, Erber WN,Bareford D, Wilkins BS, Reilly GT, Harrison CN, Green AR.Definition of subtypes of essential thrombocythaemia and relation to polycythaemia vera based on JAK2 V617F mutation status: a prospective study .Lancet 2005;366:1945-53. 9.Ganget N, Wolanskyj AP,Schwager S, Tefferi A.predictors of pregnancy outcome in essential thrombocythaemia ; a single institution study of 63 pregnancies. Eur J Haematol.2009 May ;82 (5): 350-3. 10. Randl ML, Rossi C, Fabris F, Girolmi A. essential thrombocuthaemia in young adults; major thrombotic complications and complications during pregnancy –a follow up study in 68 patients.Clin Appl Thromb Hemost.2000 Jan ; 6(1) : 31-5. 11.British Committee for Standards in Haematology.Guidelines for investigation and management of adults and children presenting with thrombocytosis.Br J Haematol . Mar 2010.149: 352-75. .