Nonneoplastic placental conditions and abnormalities



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PubMed Search: Erythroblastosis [title] placenta

Mandolin S. Ziadie, M.D.
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Cite this page: Ziadie MS. Erythroblastosis. website. Accessed September 27th, 2023.
Definition / general
  • Nucleated fetal red blood cells (nRBCs) are common in preterm placentas but are an abnormal finding in placentas at term
  • nRBCs reflect a response to fetal hypoxia or anemia due to a variety of causes including uteroplacental insufficiency, abruption, maternal diabetes, hemolytic disease of the newborn / ABO incompatibility, chronic fetomaternal transfusion, acute blood loss or chromosomal disorders
Microscopic (histologic) description
  • Red cells that are smaller than nonnucleated red cells and have round, basophilic nuclei with smooth nuclear surfaces, surrounded by a thin rim of eosinophilic cytoplasm
  • Number of cells per 10 HPF is counted
  • Grading: mild (cells are easily found in preterm placentae and are rare / occasional at term), moderate (cells easily found at all gestations) and severe (markedly increased cells at all gestations, with at least one in each HPF)
Microscopic (histologic) images

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Placental hydropic change accompanied by increased fetal erythroblasts and nucleated RBCs in fetal vessels in villi

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