Variations in both α-spectrin (SPTA1) and ß-spectrin ( SPTB ) in a neonate with prolonged jaundice in a family where nine individuals had hereditary elliptocytosis.

We cared for a neonate who had problematic hyperbilirubinemia born into a family where nine first-degree relatives had hereditary elliptocytosis (HE). As neonates, the nine relatives did not have any significant jaundice or anemia that was recognizable. Blood films on the proband suggested a diagnosis of pyropoikilocytosis. Analysis of the α-spectrin gene (SPTA1) in the proband revealed two previously reported low-frequency heterozygous polymorphisms of unknown clinical significance and the α(LELY) allele. In addition, a novel heterozygous mutation was identified in exon 2 of the ß-spectrin gene SPTB. No mutations were identified in ANK1 (ankyrin-1), SLC4A1 (band 3), EPB41 (band 4.1), or EPB42 (band 4.2).

Acute kernicterus in a neonate with O/B blood group incompatibility and a mutation in SLC4A1.

We cared for a term female newborn, who at 108 hours of age, with a total serum bilirubin of 15.4 mg/dL, was discharged from the hospital on home phototherapy. At a return appointment 44 hours later, her total serum bilirubin was 41.7 mg/dL and signs of acute kernicterus were present. Maternal/fetal blood group O/B incompatibility was identified, with a negative direct antiglobulin test, which was positive on retesting. She had abundant spherocytes on blood smear, and these persisted at follow-up, but neither parent had spherocytes identified. A heterozygous SLC4A1(E508K) mutation (gene encoding erythrocyte membrane protein band 3) was found, and in silico predicted to result in damaged erythrocyte cytoskeletal protein function. No mutations were identified in other red cell cytoskeleton genes (ANK1, SPTA1, SPTB, EPB41, EPB42) and the UGT1A1 promoter region was normal. Neurologic follow-up at 2 and 4 months showed developmental delays consistent with mild kernicterus.