Acta Scientific Paediatrics (ISSN: 2581-883X)

Case Report Volume 4 Issue 1

Unusual Presentation of Remethylation Disorders: A Case of Later Onset CblE Deficiency

Silvia Kalantari1, Francesco Porta2*, Tiziana Vaisitti1, Silvia Deaglio1 and Marco Spada2

1Immunogenetics and Biology of Transplantation, Città della Salute e della Scienza, University Hospital of Turin and Medical Genetics, Department of Medical Sciences, University of Turin, Turin, Italy
2Department of Pediatrics, University Hospital of Turin, Regina Margherita Children’s Hospital, Torino, Italy

*Corresponding Author: Francesco Porta, Department of Pediatrics, University Hospital of Turin, Regina Margherita Children’s Hospital, Torino, Italy.

Received: October 06, 2020; Published: December 10, 2020



Methylcobalamin deficiency type CblE is a rare autosomal recessive inborn error of intracellular cobalamin metabolism. The clinical presentation is characterized by megaloblastic anemia, delayed psychomotor development, hypotonia, seizures, nystagmus, impaired visual acuity, and failure to thrive. The symptoms onset is usually within the 3rd year of life, with most children presenting within the first. The biochemical markers of CblE deficiency are hyperhomocysteinemia, homocystinuria and hypomethioninemia. We report a case of late onset (11 yo) methylcobalamin deficiency type CblE presenting with isolated macrocytic anemia and no neurological impairment. Genetic analysis of the MTRR gene allowed to identify two compound heterozygous variants, c.626C>G; [p.(Ser209*)] and c.1715C>T [p.(Pro572Leu)], which were never reported in the literature before. The therapy with hydroxocobalamin was effective on the patient anemia and allowed to reach control of the clinical picture. The aim of this article is to show that isolated macrocytic anemia and hyperhomocysteinemia may be caused by a remethylation disorder, even when the clinical presentation is milder than expected.

Keywords: Vitamin B12 Intracellular Metabolism; CblE Disease; Late Onset; Hyperhomocysteinemia; Macrocytic Anemia



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Citation: Francesco Porta.,et al. “Unusual Presentation of Remethylation Disorders: A Case of Later Onset CblE Deficiency”. Acta Scientific Paediatrics 4.1 (2021): .


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