What are the causes of elliptocytes, ovalocytes, and macrocytes on a peripheral blood smear (PBS)?

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From the Research

Causes of Elliptocytes

  • Hereditary elliptocytosis is a heterogeneous red blood cell membrane disorder characterized by the presence of elliptocytes on a peripheral blood smear 1, 2
  • It can be caused by mutations in the EPB41 gene, which results in a frameshift and a premature stop codon, encoding a truncated protein 2
  • Hereditary elliptocytosis can also be coinherited with other conditions, such as deletional hemoglobin H disease 1

Causes of Ovalocytes

  • Southeast Asian ovalocytosis (SAO) is characterized by macro-ovalocytes and ovalo-stomatocytes on blood smear 3
  • SAO is caused by a deletion of codons 400-408 in the SLC4A1 gene, which encodes for band 3 erythrocyte membrane protein 3
  • This deletion results in an unusual erythrocyte stiffness and oval shape of the cells on blood smear 3

Causes of Macrocytes

  • Macrocytosis can be caused by various conditions, including alcoholism, vitamin B12 and folate deficiencies, and medications 4, 5
  • It can also be caused by hypothyroidism, liver disease, and primary bone marrow dysplasias, including myelodysplasia and myeloproliferative disorders 4
  • Macrocytosis can be evaluated using a peripheral smear, which can indicate megaloblastic anemia or non-megaloblastic causes 4, 5

References

Research

Coinheritance of Hereditary Elliptocytosis and Deletional Hemoglobin H Disease.

Journal of pediatric hematology/oncology, 2017

Research

Evaluation of macrocytosis.

American family physician, 2009

Research

Evaluation of macrocytosis in routine hemograms.

Indian journal of hematology & blood transfusion : an official journal of Indian Society of Hematology and Blood Transfusion, 2013

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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