Workup included a negative direct antiglobulin test (DAT) and normal glucose-6-phosphate dehydrogenase and pyruvate kinase testing; Hemoglobin electrophoresis showed normal Hemoglobin A and F percentages for age. Both mom and patient have A+ blood type. She had no liver or kidney dysfunction.
Diagnosis: Infantile pyknocytosis
Infantile pyknocytosis, although rare, is a recognized cause of hemolytic anemia in newborns around 2 to 3 weeks of age. Patients present with anemia and jaundice, requiring phototherapy and potentially transfusion. Other causes of hemolytic anemia, as well as liver and kidney disease, must be ruled out prior to making the diagnosis of exclusion, as described in this patient’s case. The blood smear shows the characteristic contracted, hyperdense and spiculated pyknocytes.
Diagnosis: Infantile pyknocytosis
Infantile pyknocytosis, although rare, is a recognized cause of hemolytic anemia in newborns around 2 to 3 weeks of age. Patients present with anemia and jaundice, requiring phototherapy and potentially transfusion. Other causes of hemolytic anemia, as well as liver and kidney disease, must be ruled out prior to making the diagnosis of exclusion, as described in this patient’s case. The blood smear shows the characteristic contracted, hyperdense and spiculated pyknocytes.