Hematological Diseases in Pregnancy

Anemia in Pregnancy

 Hgb Level in pregnancy: 1st & 3rd trimester Hgb < 11g/dl 2nd trimester Hgb < 10.5g/dl

Dilatational effect of pregnancy: Increase in plasma volume  dilution affect (levels decrease)  Normal Lab Ranges in Pregnancy: Ferritin (iron stors) 20 – 150 ng/ml Folate 3 – 18 ng/ml B12 (Combalamin) 250 – 1200 pg/mL MCV 80 – 100 Hgb A1 >95% Hgb A2 <3.5%  Investigations: 1. CBC  Standard lab test Hb, Hematocrit, MCV and platelet (rule out thrombocytopenia) A. Check Hb < 9g/dl B. MCV < 80  most likely Iron deficiency anemia C. Ferritin < 20  confirmed iron deficiency anemia > 15  Hb electrophoresis D. Hb electrophoresis  Normal  normal but if Asian or African  Genets  risk of thalassemia) Abnormal  +ve for sickle  Hemoglobinopathy Refer to hematologist for management outline, mostly they will need folic acid supply + iron

Normocytic Anemia A. Low Hb, Normal MCV B. Reticulocyte count  more or less than 3% If more  Combs test G6PD + Hemoglobinopathy  -ve combs test If less  RDW C. Refer to hematologist

Megaloblastic Anemia A. Anemic patient, High MCV

B. B12 & Folate If B12 deficiency  Megaloblastic anemia C. Management  Vitamin B12 + folic acid Iron Deficiency Anemia:  In reality, the most common cause of anemia on pregnancy  Treatment:  Daily iron requirement in pregnancy is 27 mg  Preparations; 1. Ferrous Fumarate 2. Ferrous Sulfate 3. Ferrous Gluconate  Elemental iron  amount of iron absorbed  Dropping Hb  three ways to correct 1. Oral:  Gastric irritations  Constipation  Some people cannot tolerate iron tablets 2. IV: . Thrombophlebitis . Infection at injection site 3. Blood transfusion (critical, rapid and fast)  Triple iron: three iron medications 1. High dose iron 2 or 3 times a day. 2. Folic acid 3. Vitamin C {ascorbic acid} If she is compliance with medication  Hb correction within 4 weeks  You have to think about the underlying cause, why is she anemic? 1. Poor iron intake (nutritional) 2. Chronic loss  ask about … A. History menorrhagia B. History of melena (stool test  occult blood) C. History of hemoptysis

Rh Iso-immunization Hemolytic Diseases of the Fetus/Neonate

 Immunological disorder that occurs in pregnancy Rh- mother carrying Rh+ fetus  Blood Groups: A, B, AB  have surface antigens O doesn’t

If the mother is Rh+  we don’t have a problem. If the mother is Rh-  the fetus is Rh- , we don’t have a problem The fetus is Rh+!!  the mother will sensitize anti D antigen

How do we know if the fetus is + or -? From the father Father +  the baby might be + Father heterozygous -  the baby might be +

 Pathopysiology: 1st pregnancy Mother Rh-, baby Rh+ Was not given anti D  at time of delivery  feto-maternal hemorrhage (Fetal blood will go to the maternal circulation)

It can happen at any time during pregnancy; trauma or any kind of intervention (Amniocentesis)  Mother will sensitize anti D antigen, it will not harm her.

2nd pregnancy Mother Rh- + sensitized ani D antibody, baby Rh+ IgG (anti D) can cross the placenta  fetal circulation Fetal blood is covered with D antigen Acquired anti D from the mother  Hemolytic disease in the baby It can be manifested intrauterine (Fetal Anemia)  US hydrops fetalis

 Risk of Immunization 2%: 1) After delivery  most common 2) Spontaneous abortion 3) Induced abortion 4) Ectopic pregnancy 5) Intensive procedures; Amniocentesis, Chronic Villus Sampling 6) Abdominal trauma 7) After external cephalic version

 How do we quantify the amount of bleeding? By Kleihauer-Betke Test  draw maternal blood and check for the fetal blood If fetal blood < 30  one shot of anti D is enough If fetal blood > 30  extra shot of anti D  Clinical Management: The diagram is important. 1) We draw maternal blood Rh- with antibody RhD + 2) Check the father  Rh- homozygous The baby is fine, no need to do anything

If the father is heterozygous or Rh+  Check maternal titer (concentration of D antigen or E antibody, ratio results)

Previously we used do amniocentesis to check on fetal blood group, any hemolysis in the amniotic fluid from the fetal blood Now  MCS PSV Doppler MCA (meddle cerebral artery) PSV (peak systolic velocity) Doppler (assessment of blood flow)

Anemic fetus  fetus body will supply vital organs (brain)  high blood flow + low viscosity (because of hemolysis)  liquidly (watery) fetal blood + diverging blood rapidly to the brain  high velocity

 If high, we should dilute the mother’s sample blood to neutralize the antibody. Usually 1/32  if increases; MCA PSV Doppler  if MCA abnormal; fetal blood transfusion in utero

 Prevention: 1) Blood group 2) Antibody screening  all pregnant women 1st visit If negative  repeat at 28 week of gestation If still negative  give her Rh immunoglobulin (anti D) Prophylaxis

If positive  define antibody; RhD  should receive Rh immunoglobulin (anti D) All women who’s screening test is (–) but experiences any of the risks mentioned above, should receive Rh immunoglobulin (anti D) before 12 weeks of gestation. 3) Antibody titer 4) If increases; MCA PSV Doppler 5) Fetal blood transfusion if MCA PSV > 1.5 MOM

 Molar pregnancy  there is no fetal tissue  Rh immunoglobulin is not necessarily Partial molar pregnancy  she needs Rh immunoglobulin  The greater risk of feto-maternal hemorrhage is at time of delivery  she needs Rh immunoglobulin to all Rh-negative + anti D-negative mothers and Rh-positive babies. If delivery is complicated by excessive hemorrhage  give another Rh immunoglobulin shot

Thrombocytopenia

 Etiology: 1) Increased destruction  autoimmune 2) Consumptive  TTP, DIC 3) Reduced production  bone marrow  Maternal thrombocytopenia: 1) Gestational/ pregnancy induced (most common) 2) Hypertensive disorders; preeclampsia/ HELP syndrome 3) Immuno-thrombocytopenic purpura (Autoimmune)

Gestational Thrombocytopenia

 Incidental finding  Pathophysiology: 1) Accelerated platelet activation is suspected to occur at placental circulation. 2) Accelerated consumption of platelets is due to reduced life span during pregnancy  How do I be sure it is gestational? 1) It occurs 2nd half of pregnancy (last half) 2) No positive history nor symptoms of thrombocytopenia {With exception of thrombocytopenia in previous pregnancy} 3) No associated fetal thrombocytopenia 4) Should resolve after delivery 5) Mild thrombocytopenia  90%  platelet count > 100 x 109 /L 6 %  platelet count < 100 x 109 /L 1 %  platelet count < 70 x 109 /L  Management: 1) Antepartum  no treatment is necessary 2) Labor and delivery  decisions should not be made depending on thrombocytopenia 3) Regional anesthesia consideration

Hypertensive Disorders; Preeclampsia/Eclampsia/HELP syndrome

 H; hemolysis EL; Elevated liver enzymes LP; Low platelets  Moderate platelets drop, rarely < 20,000  Correlated with disease severity  There are other findings than low platelets; High blood pressure Abnormal blood test Not an isolated finding, there are other supportive findings  Pathophysiology  Vascular endothelial damage increases platelet activation  Treatment: 1) Ultimate treatment  delivery Goal  maintain platelet count A. Vaginal delivery  > 20,000 B. C- section  > 50,000 If platelets <50,000, platelet transfer before surgery 2) Regional anesthesia  not recommended  epidural hematoma

Immuno-thrombocytopenia Purpura  Pathophysiology: 1) Antibodies directed against platelet glycoproteins 2) Antiplatelet antibodies may cross the placenta  Maternal treatment: 1) Platelets > 50,00  no need for treatment 2) Platelets < 50,000; A. Oral steroids  response time 3-7 days B. IVIG (intravenous immunoglobulin) response time 6-72 hours C. Splenectomy D. Platelet transfusion  Fetal consideration: 1) Sever neonatal thrombocytopenia 2) Intracranial hemorrhage  not related to delivery mode 3) Virginal delivery using instruments  intracranial hemorrhage 4) C –section  obstetric indication only Sickle Cell Disease

 Autosomal recessive  Chronic hemolytic anemia & vaso-occlusive events  Mild to moderate  Diagnosis  Hb electrophoresis

 Effects of sickle cell anemia on pregnancy: 1) Pregnancy loss (1st trimester) 2) Fetal death 3) IUGR 4) Small for gestational age 5) Acute anemia 6) Painful crisis 7) UTI 8) Preterm birth 9) Preeclampsia 10)Antepartum admission 11)Postpartum infection Top four are the most common

 Effect of pregnancy on sickle cell anemia: 1) Maternal mortality (due to inappropriate management) 2) Acute chest syndrome 3) Thromboembolic events 4) Sepsis 5) UTI

 Prenatal Care: 1) Proper history  blood transfusion, ICU admission, recent vaso- constrictive crisis 2) Lab studies  blood test (blood diseases, blood group, antibody status) 3) Serial urine culture  prone to have UTI 4) CBC repeated every trimester 5) Folate supplementation  4 mg/day + prenatal vitamins Ferrous sulfate if iron deficient 6) Pneumococcal and influenza vaccines

 Therapy: 1) Painful crisis  hydration + analgesia 2) Transfusion: A. Symptomatic or orthostatic from anemia B. Hb <6g/dL C. Hematocrit < 25% D. Acute stroke or chest syndrome E. Multiple organ failure Thalassemia

 Absent or underproduction of a structurally normal Hb chain  Alfa-thalassemia  Alfa-globin is under-produced  Beta-thalassemia  Beta-globin is under-produced  Fragile red cells  Associated with: Fetal hydrops Fetal hydrops  accumulation of fluids in two compartments or more in the baby; Plural effusion Pericardial effusion Skin edema Acitis  Needs iron + folic acid supplementation  Needs monitoring