Nuance of nucleated RBCs (Normoblastemia) in peripheral blood film

Abstract

Nucleated RBCs (NRBCs) are immature RBCs normally they are not seen in the peripheral blood after the neonatal period. Their presence in peripheral blood of children and adults signifies bone marrow damage or stress and potentially serious underlying disease. The presence of numerous NRBCs increases the WBC count in automated hematology analyzers. Most analyzers generate suspect flags for identifying abnormal cells, and the samples involved should be reviewed manually. Unfortunately, analyzers may not detect low levels of NRBCs. We recommend correcting the WBC count with even 1 NRBC/100 WBCs and reporting “occasional NRBC seen.” This alerts clinicians for the significance of unexplained normoblastemia.