HEMOLYTIC DISEASE OF NEWBORN Assoc. Prof. Dr. Victoria ATANASOVA, MD, PhD Clinic of Neonatology UMHAT, Pleven

BACKGROUND 1609 – A French midwife reported hemolytic disease of the newborn (HDN) in a set of twins 1932 → Relationship among fetal hydrops, jaundice, anemia, and erythroblasts in the circulation (Diamond & coll.) ═► erythroblastosis fetalis 1940 → Rh blood group system (Landsteiner & Weiner) → the cause of disease (Levine) MODERN OB-GYN SCHOOL 22-23.04.2017

Anti-D prophylaxis in Bulgaria – since 1977 !!! BACKGROUND 1966 – the history of anti-D immunoglobulin G (IgG) prophylaxis starts → 1971 (WHO) – protocol of anti-D prophylaxis → 1998 (American Association of Blood Banks and the American College of Obstetrics and Gynecologists) – the WHO-recommendation was reinforced Anti-D prophylaxis in Bulgaria – since 1977 !!! MODERN OB-GYN SCHOOL 22-23.04.2017

DEFINITION BLOOD GROUP INCOMPATIBILITY = ISO-SENSITIZATION / ISO-IMMUNISATION = HEMOLYTIC DISEASE OF THE FETUS AND NEWBORN Incompatibility between the blood of the mother ant fetus according to some antigens (Ags) which are available in the fetus blood (inherited from the father) and missing in the mother blood ═► Immuno aggressive condition of the mother in regard to the fetus MODERN OB-GYN SCHOOL 22-23.04.2017

TYPES OF INCOMPATIBILITY Rh-incompatibility – most often → 10% from all pregnancies → 1 : 200-250 deliveries in the past (before anti-D-prophylaxis) Types Rh-Ag: D, E and C (Fisher & Race); The most often Rh-conflict → D-Ag MODERN OB-GYN SCHOOL 22-23.04.2017

TYPES OF INCOMPATIBILITY ABO-incompatibility → mother – О / baby А (90%) or В (10%) Rh-Ags expression – in red blood cells (RBCs) and is missing in RBCs progenitors ↕ A- and B-Ags are widely expressed in various tissues besides RBCs Incompatibility under other Ags - M, N, Hr, Kell, Kidd, Duffy etc. – rare cases and difficult to prove MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOPHYSIOLOGY Antibody (Ab) production against some of RBCs-Ags – 2 or more Ags-stimuli : І – strong enough → primary immune response ІІ – anamnestic immune response, with significantly lower blood amount MODERN OB-GYN SCHOOL 22-23.04.2017

Ways of exposure of mother to foreign RBC-Ags: PATHOPHYSIOLOGY Ways of exposure of mother to foreign RBC-Ags: Massive exposure: Transfusion of incompatible blood During the delivery, abruptio placentae, ectopic pregnancy Surgery interventions MODERN OB-GYN SCHOOL 22-23.04.2017

Ways of exposure of mother to foreign RBC-Ags: PATHOPHYSIOLOGY Ways of exposure of mother to foreign RBC-Ags: Minimal exposure: Abortion – spontaneous or therapeutic Through the placenta during the pregnancy – in the 75% of pregnancies and increases to the term (< 0,1 mL) Prenatal diagnostic procedures (amniocentesis, chorionic villus sampling, and cordocentesis) MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOPHYSIOLOGY Primary immune response: initial exposure of the mother to a foreign Ag → Abs of the IgM isotype (mother sensitization) Secondary immune response → Abs of the IgG isotype across the placenta to the fetus► + fetal RBCs (after 20th GW) → fetal liver and spleen → extravasal hemolysis MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOPHYSIOLOGY Prolonged hemolysis Anemia ↑ bil → jaundice (in the newborn only!) ↑ medullary and extra medullary hemopoiesis (liver, spleen, skin, placenta) Liver dysfunction → hypoproteinemia MODERN OB-GYN SCHOOL 22-23.04.2017

PATTERNS OF DIFFERENT KINDS OF ISOIMMUNIZATIONS Rh incompatibility: Usually from the second pregnancy Transplacental transfer of Abs of the IgG isotype after the 20th GW Trends to aggravate in each subsequent pregnancy MODERN OB-GYN SCHOOL 22-23.04.2017

PATTERNS OF DIFFERENT KINDS OF ISOIMMUNIZATIONS ABO-incompatibility: Anti-A and anti-В-Abs (IgM) – normal finding in individuals with О blood group = primary sensitization Minimal amount of fetal RBCs → complete sensitization ═► ½ of the cases – from the first pregnancy Anti-A and anti-В-Abs attach to the fetal RBCs in the later stages (usually to the birth) No trends to become progressively worst with each pregnancy MODERN OB-GYN SCHOOL 22-23.04.2017

PATTERNS OF DIFFERENT KINDS OF ISOIMMUNIZATIONS Kell-incompatibility: Kell-Ags are expressed on the surface of RBC-progenitors → hemolysis + erythropoiesis suppression Rare causes – Duffy- и MNS-incompatibility No cases of incompatibility under Lewis- и Р-Ags MODERN OB-GYN SCHOOL 22-23.04.2017

Signs of hemolytic anemia: PATHOGENESIS Signs of hemolytic anemia: Anemia with erythroblastosis Hyperbilirubinemia Fetal hydrops MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOGENESIS Progressive anemia with compensatory response of hemopoiesis Usually in Rh-incompatibility Severe anemia (up to 20% of cases) → Intrauterine fetal death → Early neonatal death Moderate anemia (in 80% of cases) MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOGENESIS Hyperbilirubinemia due to hemolysis typical for mild cases of Rh- and especially for АВО-incompatibility Early and rapidly progressive jaundice Indirect fraction of bilirubin (pervade into all tissues) MODERN OB-GYN SCHOOL 22-23.04.2017

PATHOGENESIS Genesis of fetal hydrops: Anemia (Hgb < 40 g/l; Hct < 0,15) Excessive extra medullary hepatic hemopoiesis → hepatic and umbilical venous obstruction ↓ placental perfusion → edematous placenta → diminished placental perfusion Hypoxic injure of myocardium and vessels → (congestive) cardiac failure Tissue hypoxia → capillary leak syndrome Liver damage + portal hypertension → ascites, ↓ albuminemia MODERN OB-GYN SCHOOL 22-23.04.2017

CLINICAL PRESENTATION Intrauterine fetal death (macerated, edematous fetus, 20th-30th GW) Swelling (hydrops fetalis, immune hydrops) Premature delivery (26th-28th GW) Hydramnion Massive edema – visceral cavities, subdermal, placenta Severe anemia (Hgb < 40 g/l); erythroblastemia Hypoproteinemia Hemorrhagic syndrome MODERN OB-GYN SCHOOL 22-23.04.2017

CLINICAL PRESENTATION Jaundice Term neonates Hyperbilirubinemia Yellow colored amniotic fluids, umbilical cord, vernix T-bil (umbilical blood) > 51 mcmol/l Early and progressive jaundice CNS injury (kernicterus) Liver dysfunction Hemorrhagic syndrome Hypoproteinemia Tick bile syndrome (mechanical / obstructive jaundice) Anemia (continuous hemolysis !) MODERN OB-GYN SCHOOL 22-23.04.2017

CLINICAL PRESENTATION Anemia Anemia fetalis gravis (~ 5% of cases of Rh- incompatibility) Hgb 40-100 g/l at birth Hemorrhagic syndrome → DIC Severe hypoglycemia Often → tick bile syndrome Moderate anemia (continuous hemolysis !) MODERN OB-GYN SCHOOL 22-23.04.2017

LABORATORY STUDIES Signs of hemolytic state: Metabolic disturbances: Anemia Indirect hyperbilirubinemia Reticulicytosis Erythroblastosis ↑ LDH Metabolic disturbances: Hypoglycemia Electrolyte disturbances (Са++, К+) MODERN OB-GYN SCHOOL 22-23.04.2017

LABORATORY STUDIES Serologic tests: Indirect Coombs test and direct antibody test In Rh-incompatibility (+) In АВО-incompatibility – (+) in 20-40% of newborns only Indirect antiglobulin test (serum from the newborn + adult А- or В-RBCs) – in АВО- incompatibility IgG1, IgG2, IgG3 MODERN OB-GYN SCHOOL 22-23.04.2017

PRENATAL DIAGNOSIS Of the pregnant woman: Pregnancy in Rh(-)-♀ from Rh(+)-♂ with suspect of isoimmunisation situations in ♀ At Ob-gyn risk – still birth, spontaneous abortion, previous child with HDN, child with neurodevelopmental delay Serial serologic testing → Abs critical level = 1/32 In Kell incompatibility – 1/8 !!! MODERN OB-GYN SCHOOL 22-23.04.2017

PRENATAL DIAGNOSIS Fetus: Examination of amniotic fluids by amniocentesis (optical density, bilirubin level) → Liley (1961) Pic systolic blood pressure in arteria cerebri media (Doppler) → grade of fetal anemia MODERN OB-GYN SCHOOL 22-23.04.2017

Indices of severe fetal hemolytic disease: PRENATAL DIAGNOSIS Indices of severe fetal hemolytic disease: Previous children with HDN Increasing of mother Abs level Increasing of amniotic bilirubin level US-data of fetal hydrops (ascites, edema, effusions, worsened biophysical profile, decreased fetal Hgb) MODERN OB-GYN SCHOOL 22-23.04.2017

DIFFERENCIAL DIAGNOSES Congenital infections (Parvovirus В19, Toxoplasmosis, Lues, CMV) Inborn errors of metabolism (hypothyreoidismus congenita, thyrosinemia) Fetal cardiac problems (cardiac tumors, arrhythmia) MODERN OB-GYN SCHOOL 22-23.04.2017

LATE COMPLICATIONS Bilirubin encephalopathy (Kernicterus) Late anemia – causes: Blood transfusions of adult RBCs → ↓ ЕРО Circulating iso-Abs → continuing hemolysis MODERN OB-GYN SCHOOL 22-23.04.2017

ANTENATAL TREATMENT Interruption of pregnancy ~ 32nd GW Treatment of mother alloimmunisation: Medication and bio suppression of iso-Ab production – non effective Plasmaferesis, IVIG – moderately effective Intrauterine blood transfusion: Intraperitoneal (Liley, 1963) Intravasal (Rodeck, 1981) MODERN OB-GYN SCHOOL 22-23.04.2017

POSTNATAL TREATMENT MODERN OB-GYN SCHOOL 22-23.04.2017

PREVENTION of HDN In pregnancies at-risk: Serologic screening Bio prophylaxis with specific (anti-D) immunoglobulin: In 28th GW Up to 72nd postnatal hour MODERN OB-GYN SCHOOL 22-23.04.2017

PREVENTION of HDN In non-sensitized women after event associated with trans placental hemorrhage: After abortion, Ectopic pregnancy, Amniocentesis, chorionic villus sampling, Late fetal death... MODERN OB-GYN SCHOOL 22-23.04.2017

victoria_atanasova@yahoo.co.uk MODERN OB-GYN SCHOOL 22-23.04.2017