Acute Kernicterus in a Neonate With O/B Blood Group Incompatibility and a Mutation in SLC4A1 abstract

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 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. Pediatrics 2013;132:e531–e534 AUTHORS: Robert D. Christensen, MD,a Hassan M. Yaish, MD,b Roberto H. Nussenzveig, PhD,cd N. Scott Reading, PhD,cd Archana M. Agarwal, MD,cd Larry D. Eggert, MD,a and Josef T. Prchal, MDcde aWomen and Newborns Program, Intermountain Healthcare, Salt Lake City, Utah; bDivision of Hematology/Oncology, Department of Pediatrics, cDepartment of Pathology, and eDivision of Hematology, Departments of Genetics and Pathology, University of Utah School of Medicine, Salt Lake City, Utah; and dARUP Laboratories, Salt Lake City, Utah