Differential Diagnosis for Anemia in a 13-month-old Girl
- Single most likely diagnosis
- Iron deficiency: The patient's laboratory values, including a low hemoglobin level (7.2 g/dL), a mean corpuscular volume (MCV) of 61 fL indicating microcytic anemia, and a low absolute reticulocyte count (1.5%), are consistent with iron deficiency anemia. The age of the patient and the absence of other symptoms also support this diagnosis, as iron deficiency anemia is common in infants and toddlers due to rapid growth and inadequate dietary intake.
- Other Likely diagnoses
- Lead poisoning: Although less likely than iron deficiency, lead poisoning can cause microcytic anemia with similar laboratory findings. Lead exposure is a concern in young children, especially those living in older homes with lead-based paint.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Hemolytic anemia: While the patient's peripheral smear does not show atypical cells, hemolytic anemia can present with varying degrees of anemia and should be considered to avoid missing a potentially life-threatening condition. Further testing, such as direct Coombs test or hemoglobin electrophoresis, may be necessary to rule out hemolytic anemia.
- Rare diagnoses
- Folate deficiency: Folate deficiency typically causes macrocytic anemia, which is not consistent with the patient's microcytic anemia (MCV of 61 fL). However, it is included in the differential diagnosis as a rare possibility, especially if there are other underlying conditions affecting folate metabolism.
- Other rare causes of microcytic anemia, such as thalassemia or congenital disorders of iron metabolism, should also be considered, although they are less likely given the patient's age and presentation.