Rhesus Antigen and Pathophysiology Quiz

The fetus may die in utero due to heart failure.

Rh-immune globulin (Rh Ig) 300 mcg is administered between 28-32 weeks gestation.

Too small a dose or administering the dose later than 72 hours post-delivery.

<p>It identifies the presence of cell-destroying antibodies in the mother's plasma.</p> Signup and view all the answers

<p>It determines the percentage of fetal blood cells in the maternal circulation.</p> Signup and view all the answers

<p>It indirectly measures the degree of hemolysis of fetal red blood cells.</p> Signup and view all the answers

<p>Titers are repeated every month until 24 weeks and more frequently in the third trimester.</p> Signup and view all the answers

<p>Zone III indicates severe disease that may require transfusion or delivery.</p> Signup and view all the answers

<p>The main immunogenic Rh antigen responsible for incompatibility is the D antigen, significant due to its ability to induce strong immunologic reactions in Rh-negative individuals.</p> Signup and view all the answers

<p>Upon exposure to the Rh D antigen, an Rh-negative mother perceives it as a foreign threat, activating immune pathways that produce anti-D antibodies.</p> Signup and view all the answers

<p>The likelihood depends on the partner's Rh status; if the partner is Rh-positive, there's a 100% chance if homozygous and 50% if heterozygous.</p> Signup and view all the answers

<p>Hydrops fetalis is an abnormal accumulation of fluid in fetal tissues and cavities, commonly caused by hemolytic anemia, congenital heart defects, and chromosomal anomalies.</p> Signup and view all the answers

<p>Feto-maternal hemorrhage is only 5% in the first trimester but increases to 47% in the third trimester, influencing primary sensitization risks.</p> Signup and view all the answers

<p>The degree of fetal anemia is assessed by measuring ductus venosus blood flow and the peak systolic velocity of the fetal middle cerebral artery using Doppler ultrasound.</p> Signup and view all the answers

<p>Hydrops fetalis is a severe condition characterized by fetal edema, often resulting from extensive hemolysis caused by maternal anti-D antibodies.</p> Signup and view all the answers

<p>Amniocentesis is significant as it allows for the measurement of bilirubin levels in amniotic fluid, which helps assess the severity of fetal anemia quantitatively using the 'Liley' curve.</p> Signup and view all the answers

<p>If the mother produces anti-D antibodies, the fetus may experience hemolysis leading to anemia, jaundice, or hydrops fetalis.</p> Signup and view all the answers

<p>Intrauterine blood transfusion is warranted for a preterm fetus with significant fetal anemia and evidence of hydrops fetalis, particularly if the mother's blood sample shows Hb &gt;1g/dL.</p> Signup and view all the answers

<p>The placenta facilitates the transfer of bilirubin from fetal blood to maternal circulation, helping to manage bilirubin levels.</p> Signup and view all the answers

<p>For exchange transfusion, the blood must be less than a week old, Rh and ABO compatible with both mother and baby, and tested for CMV and hepatitis viruses.</p> Signup and view all the answers

<p>Prevention involves early identification of Rh status and administering Rh immunoglobulin to Rh-negative mothers during and after pregnancy.</p> Signup and view all the answers

<p>Treatment options include phototherapy for mild jaundice and exchange blood transfusion for moderate to severe jaundice.</p> Signup and view all the answers

<p>Dexamethasone is administered to enhance lung maturity in preterm fetuses, particularly when there are concerns about potential respiratory complications.</p> Signup and view all the answers

<p>The sensitized mother should receive advice regarding family planning, especially if the father is homozygous for the Rh gene, as there is a 100% chance of having an Rh positive baby.</p> Signup and view all the answers

<p>Immune hydrops fetalis is primarily caused by blood group incompatibility, while non-immune hydrops fetalis arises from other medical conditions affecting fluid regulation.</p> Signup and view all the answers

<p>Cardiac defects and fetal anemia are two potential causes of non-immune hydrops fetalis.</p> Signup and view all the answers

<p>Ultrasound and fetal blood sampling are commonly used to diagnose hydrops fetalis.</p> Signup and view all the answers

<p>The baby's overall health, gestational age, extent of the disease, and cause of hydrops are key factors in treatment.</p> Signup and view all the answers

<p>The prognosis is poor, with a perinatal mortality rate greater than 85%, especially for those diagnosed early or with structural abnormalities.</p> Signup and view all the answers

<p>Maternal risks include rapid onset or unusual types of preeclampsia and postpartum hemorrhage.</p> Signup and view all the answers

<p>Common symptoms include severe abdominal swelling and respiratory distress.</p> Signup and view all the answers

<p>ABO incompatibility can lead to hemolytic disease in the newborn, where maternal antibodies attack fetal red blood cells.</p> Signup and view all the answers