erythroblast
Pronunciation: ih-RITH-roh-blast
An immature red blood cell precursor found in bone marrow that still contains a nucleus. Abnormal numbers or morphology indicate hematologic disorders.
Full Definition
Erythroblasts are nucleated precursor cells in the red blood cell lineage found primarily in the bone marrow. They progress through several maturation stages: pronormoblast, basophilic normoblast, polychromatophilic normoblast, and orthochromatic normoblast. The nucleus is eventually extruded to form a reticulocyte. In pediatric hematology, increased erythroblasts in peripheral blood (nucleated red blood cells) may indicate hemolytic anemia, bone marrow stress, or infiltrative diseases. Megaloblastic erythroblasts suggest vitamin B12 or folate deficiency.
Usage
Usage note: When appearing in peripheral blood, often called 'nucleated red blood cells' or 'nRBCs'.
In Context
- "The peripheral blood smear showed numerous erythroblasts, suggesting bone marrow stress." — pathology report
- "Bone marrow examination revealed dysplastic erythroblasts with megaloblastic changes." — hematology consultation