1
|
Richmond CM, Campbell S, Foo HW, Lunke S, Stark Z, Moody A, Bannister E, Greenway A, Brown N. Rapid Identification of Biallelic SPTB Mutation in a Neonate with Severe Congenital Hemolytic Anemia and Liver Failure. Mol Syndromol 2020; 11:50-55. [PMID: 32256302 DOI: 10.1159/000505886] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2019] [Indexed: 11/19/2022] Open
Abstract
Heterozygous pathogenic variants in SPTB cause autosomal dominant hereditary spherocytosis, an important cause of neonatal nonimmune hemolytic anemia. Biallelic mutations are rarely reported, all with severe neonatal presentation. We describe rapid (68 h) genomic diagnosis of homozygous β-spectrin deficiency in a newborn with severe transfusion-dependent hemolytic anemia, conjugated hyperbilirubinemia, and progressive liver failure. Trio whole-exome sequencing identified a novel biallelic SPTB variant (c.6119C>T; p.Thr2040Ile) located in the critical spectrin repeat region. Pretransfusion blood film showed marked spherocytosis including microspherocytes and nucleated erythrocytes, and eosin-5-maleimide (E5M) staining was markedly reduced, supporting pathogenicity. Both asymptomatic heterozygous parents demonstrated mildly reduced E5M staining, with occasional spherocytes and elliptocytes. Early molecular diagnosis facilitated hypertransfusion to suppress ineffective erythropoiesis and reverse hepatic dysfunction. This report broadens the genotypic and phenotypic spectrum of spectrin deficiency and highlights the utility of rapid genomic testing in facilitating early diagnosis and informing targeted therapy in critically ill patients.
Collapse
Affiliation(s)
- Christopher M Richmond
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia.,School of Medicine, Griffith University, Gold Coast, Australia
| | - Sally Campbell
- Department of Haematology, Royal Children's Hospital, Melbourne, Australia
| | - Hee W Foo
- Department of Gastroenterology, Royal Children's Hospital, Melbourne, Australia
| | - Sebastian Lunke
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia.,Department of Clinical Pathology, University of Melbourne, Melbourne, Australia.,Australian Genomics Health Alliance, Parkville, Australia
| | - Zornitza Stark
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia.,Australian Genomics Health Alliance, Parkville, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Amanda Moody
- Department of Neonatal Medicine, Royal Children's Hospital, Melbourne, Australia
| | - Elizabeth Bannister
- Department of Gastroenterology, Royal Children's Hospital, Melbourne, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Anthea Greenway
- Department of Haematology, Royal Children's Hospital, Melbourne, Australia
| | - Natasha Brown
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Melbourne, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Australia
| |
Collapse
|