QUICK REFERENCE 2013 Clinical Practice Guide on Thrombocytopenia in Pregnancy 2013 Clinical Practice Guide on Thrombocytopenia in Pregnancy by the American Presented Society of Hematology Presented by the American Anita Rajasekhar, MD, MS Society of Hematology Terry Gernsheimer, MD Anita Rajasekhar, MD, MS Roberto Stasi, MD, PhD Andra MD Terry Gernsheimer,H James, MD, MPH Roberto Stasi, MD, PhD Andra H James, MD, MPH I Introduction to Thrombocytopenia in Pregnancy • Thrombocytopenia is second to anemia as the most common hematologic abnormality encountered during pregnancy • The prevalence of a platelet count < 150 x 109/L in the third trimester of pregnancy is 6.6 to 11.6% • A platelet count of < 100 x 109/L, the definition for thrombocytopenia adopted by the International Working Group, is observed in only 1% of pregnant women The hematologist’s role is to: • determine the cause • advise in the management of thrombocytopenia • help estimate the risk to the mother and fetus II Causes of Thrombocytopenia in Pregnancy The hematologist is usually consulted in one of three scenarios: pre-existing thrombocytopenia—most commonly, immune thrombocytopenia (ITP) decreasing platelet count or newly discovered thrombocytopenia in pregnancy, which may or may not be related to pregnancy acute onset of thrombocytopenia in the setting of severe preeclampsia, the HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) or AFLP (acute fatty liver of pregnancy) Table Causes and Relative Incidence of Thrombocytopenia in Pregnancy Pregnancy-specific Not pregnancy-specific Isolated throm- Gestational thrombocy- Primary ITP (1-4%) topenia (70-80%) Secondary ITP ( 40 U/L Low platelets Platelet count < 100 x 109/L InciDiagnostic dence Features During Pregnancy (%) C Acute Fatty Liver of Pregnancy (AFLP) • AFLP is a rare but serious condition of the third trimester (1 in 20,000 pregnancies) • AFLP is characterized by elevated liver enzymes, elevated conjugated bilirubin (frequently > 5mg/dL), and coagulopathy • Thrombocytopenia is present less than half of the time • AFLP has overlapping features with HELLP, but there is no well-established definition of the condition that clearly differentiates it from HELLP Comments Gestational 5-9 thrombocytopenia •Onset at late •PLT >70 second or x 109 third trimester •Normal PLT outside of pregnancy •No neonatal thrombocytopenia •Typically normal •Unclear •Diagnosis of exclusion •Resolution of thrombocytopenia postpartum •No fetal thrombocytopenia ITP •Onset any trimester •Thrombocytopenia outside of pregnancy possible •May have signs of bleeding, bruising, petechiae •Antibody induced peripheral PLT destruction •Decreased thrombopoiesis •Diagnosis of exclusion •May be associated with fetal thrombocytopenia Platelet count < 150 x 109/L Reference: adapted from Sibai BM, Ramadan MK, Usta I, Salama M, Mercer BM, Friedman SA Maternal morbidity and mortality in 442 pregnancies with hemolysis, elevated liver enzymes, and low platelets (HELLP syndrome) Am J Obstet Gynecol 1993;169(4):1000-1006 Laboratory Clinical PathoFindings Symptoms physioland Physi- ogy cal Exam 20 weeks gestation) •Systolic BP ≥ 140mmHg or diastolic BP ≥ 90mmHg •Systemic endothelial dysfunction •Inadequate placentation HELLP syndrome 5mg/dL •Liver dysfunction more significant than in HELLP/preeclampsia •Onset any trimester, but more common during third trimester or post partum •MAHA •Elevated CR •Schistocytes on PBS •Fever •Abdominal pain •Nausea/ vomiting •Headache •Visual changes •Altered mental status •Congenital deficiency / inhibitor of ADAMTS13 (TTP) •Complement dysregulation (aHUS) •ADAMTS13 activity