Differential Diagnosis for Case 29

Based on the patient's history, CBC results, and peripheral smear images, the following differential diagnoses are considered:

• Single Most Likely Diagnosis

  • Hemoglobin E disease: Given the patient's ethnicity (from Cambodia) and the presence of a prominent poikilocyte on the slides/images, Hemoglobin E disease is a strong consideration. Hemoglobin E is a common hemoglobinopathy in Southeast Asia, and it can cause a variety of red blood cell abnormalities, including target cells and other poikilocytes.

• Other Likely Diagnoses

  • Thalassemia trait: The patient's Southeast Asian ethnicity and history of a transfusion at a young age (possibly for a thalassemia-related condition) make thalassemia trait a plausible diagnosis. Thalassemia can cause red blood cell abnormalities, including microcytosis and poikilocytes.
  • Iron deficiency anemia: Although the patient has been healthy her whole life, iron deficiency anemia is a common condition in pregnant women, especially those with a history of transfusions or possible underlying hemoglobinopathies.

• Do Not Miss Diagnoses

  • Sickle cell disease: Although less common in Southeast Asia, sickle cell disease is a critical diagnosis to consider due to its potential severity and the fact that it can cause a range of red blood cell abnormalities. Missing this diagnosis could have significant consequences for the patient and her fetus.
  • Malaria: Given the patient's history of living in a refugee camp in Thailand, malaria is a potential diagnosis that should not be overlooked, especially if the patient has any symptoms suggestive of infection.

• Rare Diagnoses

  • Other hemoglobinopathies (e.g., Hemoglobin H disease): While less common, other hemoglobinopathies could be considered, especially if the patient's ethnicity and clinical presentation suggest a possibility other than Hemoglobin E disease.
  • Red blood cell membrane disorders (e.g., hereditary spherocytosis): These disorders are less likely given the patient's age and lack of significant anemia or jaundice but could be considered if other diagnoses are ruled out and the patient's clinical presentation warrants further investigation.