Idiopathic Heinz body hemolytic anemia in newborn infants

Heinz body hemolytic anemia developed in six full-term infants while at home during the first 2 weeks of life. The disorder first manifested as hyperbilirubinemia. However, in all cases, severe anemia (hemoglobin concentration 49-73 g/L) developed during the 4-12 days of hospitalization. The infants had not been exposed to known oxidants, and their erythrocytes were not glucose-6-phosphate dehydrogenase (G6PD) deficient and contained no unstable hemoglobin. It is hypothesized that in these newborn infants, Heinz body hemolytic anemia developed as a result of ingestion of an oxidant contained in feedings. The nature of this agent is as yet unknown.