Evaluation of Erythroid Maturation Patterns in Unexplained anemia in the Elderly

In the elderly, a sizeable proportion of anemia remains unexplained. Erythroid maturation patterns may provide clues to underlying pathophysiology. Hence, this study was conducted to identify unique erythroid maturation patterns in unexplained anemia (UA) and their usefulness in providing a clue to the underlying cause of anemia. Immunophenotyping by flow cytometry was performed on bone marrow (BM) aspirates. The maturation patterns of erythroid precursors were studied, and erythroid cells were classified into early erythroid precursors (CD34+/CD117+/CD71-), proerythroblasts (CD45^neg-dim/CD71+/CD117+/CD235a-), erythroblasts (CD117-/CD71+/CD235a+) and mature erythrocytes (CD235a+). Three different patterns were observed based on CD71 expression (heterogeneous, homogeneous, and negative to dim), the percentage of CD117 + erythroid cells, and MFI CD71 (increased or decreased). Three of these cases also showed mild CD117+/CD235a + copositive aberrant/asynchronous pattern. UA cases in the elderly demonstrated three different maturation patterns. These patterns need to be validated along with a cytogenetic work-up in further studies with larger sample size and longer follow-ups to gain a better understanding of the progression of UA.