Hydrops Fetalis

Dr Manal Behery 2014

Hydrops = Generalized subcutaneous edema in the fetus or neonate

Definition

1. Excess serous fluid in at least

one space (ascites, pleural effusion, or

pericardial effusion) + skin edema (> 5 mm thick)

1. Excess fluid in two spaces without edema

Hydrops Fetalis

Non Immune Hydrops Fetalis (90%)

Immune Hydrops Fetalis (10%)

Etiology

1. Hematologic: Due to anemia (10% of cases) :

A. Isoimmune hemolytic disease (RH incompatibility).

2. Cardiovascular: Due to heart failure (20% cases)

A. Rhythm disturbances

B. Major cardiac disease

3. Infection (10% of cases) TORCH-Syphilis-Congenital

Hepatitis, Parvovirus….

4. Chromosomal (5% of cases) : Turner syndrome, trisomy

13,18,21

5. Pulmonary (5% of cases) Chylothorax, diaphragmatic

hernia

6. Gastrointestinal (5% of cases) : Meconium peritonitis

7. Renal (5% of cases) Nephrosis, RVT, urinary obstruction

…..

7. Maternal conditions (5% of cases) : Toxemia, diabetes,

thyrotoxicosis

8. Miscellaneous (10% of cases) : Cystic hygroma, wilms’

tumor – teratoma

9. -Unknown (20% of cases) :

Rh (Rhesus) Isoimmunization:

Four blood types ( A, B, AB, and O)

Each blood type is additionally classified according to the presence or absence of the Rh factor

CDE (Rhesus) System• Clinically Important

• Includes c, C, D, e, E

• Rh negative status indicates the absence of D antigen

• 87% of Caucasians carry the D antigen

•Rh Disease

•Alloimmunization

•Isoimmunization

•HDFN

•Erythroblastosis Fetalis

Confusing Terminology

When the mother produces Abs directed against fetus RBC surface Ag.

Isoimmunization

Rh Incompatibility

Exposure to fetal antigens causes the mother to produce

antibodies

The placenta usually acts as a barrier to fetal blood entering the maternal

circulation.

Fetal cells can enter the maternal circulation through a “break” in the

“placental barrier”.

Maternal production of Rhesus antibodies following introduction of Rhesus positive

blood

Maternal production of Rhesus antibodies following introduction of

Rhesus positive blood

Causes of RBC Transfer: “A break in the barrier”

• Abortion/Ectopic Pregnancy

• Partial molar pregnancy• Blighted ovum• Antepartum bleeding• Procedures

(amniocentesis, cordocentesis, CVS)

• External version• Platelet transfusion• Abdominal trauma• Inadvertent transfusion

Rh+ blood• Postpartum (Rh+baby)

Sensitized pregnancy Non- Sensitized pregnancy

Rh Incompatibility

Sensitization = Rh neg person exponsed to the Rh (D) antigen and makes antibodies against that protein (antigen).

Rh Negative Women Man Rh positive

FetusRh positive Fetus

Rh+ve R.B.C.s enter Maternal circulation

previously sensitized 2nd immune response

IgM…IgG antibodies

Non sensitized Mother Primary immune response

1st Baby usually escapes. Mother gets sensitized?

Fetus

Haemolysis

Pathogenesis Of Rh Iso - immunisation

Rh –VE Fetus

no harm

Presentation Mild jaundice

Erythroblastosis Fetalis Generalized Edema

Hepatomegaly Ascites

Natural History

• 50% of affected infants have mild anemia, requiring either phototherapy

or no treatment.

•25% have hepatosplenomegaly , moderate anemia and progressive jundice ending in kernicterus, neonatal

death

•25% are hydropic and die in utero or in the neonatal period

RhoGAM has decreased HDFN caused by anti-DGive 300 mcg dose within 72 hrs of delivery to

unsensitized Rh (-) women (Rh positive infant)

• ACOG: 300 mcg at 28 weeks UNLESS father known to be Rh (-)

Mechanism of action

• Administered antibodies will bind the fetal Rh- positive cells

• Spleen captured these cells by Fc-receptors

• Suppressor T cell response is stimulated

• Spleen remove anti-D coated red cells prior to contact with antigen presenting cells “antigen deviation”

Kleihauer-Betke Test• % fetal RBC in maternal circulation

• Fetal erythrocytes contain Hbg F which is more resistant to acid elution than HbgA so after exposure to acid, only fetal cells remain & can be identified with stain

• 1/1000 deliveries result in fetal hemorrhage > 30ml

• Risk factors only identify 50%

1.1-Direct Coomb’s Test (DAT)

Detects RBCs that have already been sensitized with IgG

Demonstrates that in vivo coating of RBC by Ab has occurred but does NOT identify the antibody

Deepa Babin @TMC Kollam 28

Detects antibodies to RBC antigens present in the patient’s serum

Detects in vitro red cell sensitization if red cells contain antigen corresponding to serum antibody

Procedure: STEP 1: patient’s serum (with unknown Ab) + RBC (with known Ag)

STEP 2: product of step 1 + Coomb’s reagent

IAT))2. Indirect Coomb’s Test

Deepa Babin @TMC Kollam 29

Recognition of pregnancy at risk

•First ante-natal visit check blood group, antibody screening.

• If indirect coombs test is positive, the father’s Rh should be tested.

• Serial maternal Anti D titers should be done every 2- 4 weeks.

• If titer is less than 1/16 the fetus is not at risk.

• If titer is more than 1/16 then severity of condition should be evaluated.

Prevention• Test for excessive fetal-maternal hemorrhage

after blunt trauma, abruption, cordocentesis, and bleeding with previa

• Give RhoGAM for partial molar pregnancy, ectopic, chorionic villus sampling, amniocentesis, external version

MCA Doppler and Fetal Anemia

• Fetuses with anemia show an • increased peak velocity of systolic blood flow in MCA.

• MCA Doppler is also used to follow fetal response to intrauterine transfusion and to assist in timing subsequent transfusions.

• Non-invasive, • no risk for worsening isoimmunization

Normal and Abnormal MCA Dopplers

Amniocentesis

- There is an excellent correlation between the amount of bilirubin in amniotic fluid and fetal hematocrit.

-

• - Perform serial amniocenteses• to the optical density deviation at 450

nm measures the amniotic fluid unconjugated bilirubin.

• Plot values on Liley Curve

at 16 weeks of gestation

Liley Curve•Measures the level of bilirubin and predicts

severity of hemolytic disease after 27 weeks

Suggested management after amniocentesis for ΔOD 450

Serial Amniocentesis

Lily zone ILower Zone II

Upper Zone II Zone IIIHydramnios & Hydrops

Repeat Amniocentesis every

2-4 weeks

Delivery at or near term

Repeat Amniocentesis in 7 days or FBS

Hct < 25%Hct > 25%

Intrauterine Transfusion

Repeat Sampling7 to 14 days

>35 to 36 weeksAnd Fetal lung

immaturity

<35 to 36 weeks Lung maturity

present

Intrauterine Transfusion

Delivery

Cordocentesis

• Gold standard for detection of fetal anemia

• Complications• 2.7% total risk of fetal loss• Reserved for patients with increased MCA-PSV or delta OD450

Intrauterine transfusion

Exchange Transfusion

• . Considered if the total serum bilirubin level is approaching 20

mg/dL and continues to rise despite intense in-hospital phototherapy.

Mortality rate 1%

Diagnosis and Management contd.

Review of Management for Rh Isoimmunization

• Monthly indirect coombs titer (in first sensitized pregnancy)

• If critical titer reached, determine paternal and fetal antigen status

• Amniocentesis and delta OD450 OR MCA-PSV

** For 2nd or greater sensitized pregnancy, initiate amnio or MCA at 18-20 weeks**