RBC anisopoikilocytosis is a condition where red blood cells (RBCs) exhibit variations in both size (anisocytosis) and shape (poikilocytosis). This means the red blood cells in a blood sample show a range of sizes and irregular, abnormal shapes, deviating from the typical biconcave disc.
Understanding the Components:
- Anisocytosis: Refers to the presence of red blood cells of varying sizes. Some cells may be larger than normal (macrocytes), while others may be smaller (microcytes).
- Poikilocytosis: Describes the presence of red blood cells with irregular shapes. These shapes can vary widely, including ovalocytes (oval-shaped), elliptocytes (ellipse-shaped), sickle cells (crescent-shaped), and others.
Causes and Associations:
Anisopoikilocytosis is not a disease itself but rather a sign of an underlying condition affecting red blood cell production or maturation. Several conditions can lead to this finding:
- Myelodysplastic syndromes (MDS): A group of bone marrow disorders impacting blood cell formation. [Example: A peripheral blood film from a patient with MDS may show marked anisopoikilocytosis.] (LearnHaem)
- Thalassemia: A group of inherited blood disorders characterized by reduced or absent hemoglobin production. [Example: Beta-thalassemia often presents with anisopoikilocytosis and nucleated red blood cells.] (PubMed)
- Pernicious anemia: A type of anemia resulting from a deficiency of vitamin B12. [Example: Cabot rings, indicating a defect in erythrocyte production, are sometimes seen alongside marked anisopoikilocytosis in pernicious anemia.] (DOI: 10.1182/blood-2017-10-809178)
- Other anemias: Various anemias can cause variations in RBC size and shape.
- Sickle cell disease: An inherited disorder characterized by abnormal hemoglobin leading to misshapen red blood cells. [Example: Sickle cell trait with β-thalassemia can show marked anisopoikilocytosis with elliptocytes.] (NCBI PMC)
Diagnosis:
Anisopoikilocytosis is typically diagnosed through a peripheral blood smear examination, where a sample of blood is viewed under a microscope. The presence and degree of anisocytosis and poikilocytosis are assessed visually. Further testing, such as complete blood count (CBC) and additional blood tests, are necessary to determine the underlying cause.
Significance:
The presence of anisopoikilocytosis is a significant finding that warrants further investigation to identify the underlying cause. Treatment is directed towards addressing the underlying condition.
