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11 Cards in this Set
- Front
- Back
What is the meaning of hydrops fetalis?
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Generalised edema of the fetus
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What are the two broad categories of causes for hydrops fetalis?
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Immune hydrops
Non-immune hydrops |
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Discuss the pathogenesis of immune hydrops
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Sensitization of mother to fetal red cell antigens
Generation of antibodies Hemolysis with progressive anaemia Tissue ischemia Cardiac failure |
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Why is rhesus disease uncommon with the first pregnancy?
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Initial exposure generates IgM which cannot cross the placental barrier
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Why is concurrent ABO incompatibility protective?
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Fetal RBC are promptly coated with isohaemmaglutinins and removed from the maternal circulation
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What is the most frequent cause of hemolytic disease of the newborn? Why?
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ABO incompatibility - not Rhesus incompatibility due to the success of prevention
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Why are infants (A and B) born to O mothers at risk of hemolytic disease of the newborn?
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Most cases generate IgM against the A and B isohaemaglutinins, but a subset of O mothers have IgG which crosses the placenta
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What are the anatomic findings in fetuses with intrauterine fluid accumulation?
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CHF
Dysmorphia (suggesting chrmosomal abnormalities) Pale (due to anaemia) Liver and spleen enlargement (from cardiac failure) Compensatory hyperplasia and extramedullary haemopoeisis |
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What are the causes for non-immune hydrops?
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Cardiovascular defects
Chromosomal abnormalities Fetal anaemia - eg thalassemia Parvovirus |
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What chromosomal abnormalities are associated with non-immune hydrops?
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45X (Turners)
trisomies 21 and 18 |
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What are the pathological basis for HF in fetal anaemia?
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Tissue ischemia - secondary myocardial dysfunction and circulatory failure
Secondary liver failure |