Differential Diagnosis
The patient's presentation of progressive lethargy, poor feeding, fatigue, increasing pallor, and specific physical examination findings, along with laboratory results, guides the differential diagnosis.
Single most likely diagnosis
- B. Fanconi anemia: This diagnosis is most likely due to the combination of physical anomalies (webbed neck, cleft palate, mild hypertelorism, flat nasal bridge, triphalangeal thumbs) and hematological findings (severe anemia with low reticulocyte count, indicating a production problem in the bone marrow). Fanconi anemia is a genetic disorder characterized by congenital anomalies, bone marrow failure, and an increased risk of malignancies.
Other Likely diagnoses
- A. Diamond-Blackfan anemia: This condition is characterized by pure red cell aplasia, which could explain the severe anemia and low reticulocyte count. However, it typically presents without the broad range of congenital anomalies seen in Fanconi anemia.
- D. Iron deficiency anemia: Although less likely given the patient's age, diet (mainly breast milk), and the presence of specific congenital anomalies, iron deficiency anemia could cause severe anemia. The mean corpuscular volume (MCV) is slightly elevated, which is not typical for iron deficiency anemia but could be seen in cases of mixed anemia.
Do Not Miss
- E. Rh incompatibility: Although the maternal blood type is O+, and the baby's blood type is A-, which does not typically cause significant hemolytic disease of the newborn, it's essential to consider any potential for hemolytic disease, especially given the severe anemia. However, the low reticulocyte count and specific congenital anomalies make this less likely.
- C. Idiopathic aplastic anemia: This is a rare condition in infants, characterized by bone marrow failure. It's crucial to consider due to its severity and the need for prompt treatment, but the presence of congenital anomalies points more towards a genetic condition like Fanconi anemia.
Rare diagnoses
- F. Wiskott-Aldrich syndrome: This X-linked recessive disorder is characterized by eczema, thrombocytopenia, and recurrent infections, which do not align closely with the patient's presentation. The normal platelet count and absence of mentioned eczema or recurrent infections make this diagnosis less likely.
- Other rare genetic disorders that could present with congenital anomalies and hematological abnormalities, such as dyskeratosis congenita or Shwachman-Diamond syndrome, should be considered if initial diagnoses are ruled out. However, they are less likely given the specific combination of findings in this patient.