Guidelines for Diagnosis and Management of the Cobalamin-related Remethylation Disorders CblC, CblD, CblE, CblF, CblG, CblJ and MTHFR Deficiency

Overview

Journal J Inherit Metab Dis

Publisher Wiley

Date 2016 Dec 2

PMID 27905001

Citations 108

Authors

Martina Huemer

Daria Diodato

Bernd Schwahn

Manuel Schiff

Anabela Bandeira

Jean-Francois Benoist

Alberto Burlina

Roberto Cerone

Maria L Couce

Angeles Garcia-Cazorla

Giancarlo la Marca

Elisabetta Pasquini

Laura Vilarinho

James D Weisfeld-Adams

Viktor Kozich

Henk Blom

Matthias R Baumgartner

Carlo Dionisi-Vici

Affiliations

Soon will be listed here.

Abstract

Background: Remethylation defects are rare inherited disorders in which impaired remethylation of homocysteine to methionine leads to accumulation of homocysteine and perturbation of numerous methylation reactions.

Objective: To summarise clinical and biochemical characteristics of these severe disorders and to provide guidelines on diagnosis and management.

Data Sources: Review, evaluation and discussion of the medical literature (Medline, Cochrane databases) by a panel of experts on these rare diseases following the GRADE approach.

Key Recommendations: We strongly recommend measuring plasma total homocysteine in any patient presenting with the combination of neurological and/or visual and/or haematological symptoms, subacute spinal cord degeneration, atypical haemolytic uraemic syndrome or unexplained vascular thrombosis. We strongly recommend to initiate treatment with parenteral hydroxocobalamin without delay in any suspected remethylation disorder; it significantly improves survival and incidence of severe complications. We strongly recommend betaine treatment in individuals with MTHFR deficiency; it improves the outcome and prevents disease when given early.

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