Case reportClinical, fluorine-18 labeled 2-fluoro-2-deoxyglucose positron emission tomography of the brain, MR spectroscopy, and therapeutic attempts in methylenetetrahydrofolate reductase deficiency
Section snippets
Patients
The disease was identified in three patients based on low/absent methionine in the blood, elevated urine homocystine and cystathionine in all [1] and absent MTHFR activity in the fibroblasts in two patients as measured by Dr. Shin [2]. In patient 1 and 2, the diagnosis was late and their disease was severe resulting in neurological crippling and significant neuroradiological abnormalities (Fig. 1A,B). However, in the third patient, who is diagnosed and treated early with a high dose methionine
Discussion
Methylenetetrahydrofolate reductase (MTHFR) (EC 1.5.1.20) is a cytoplasmic enzyme which catalyses the reduction of methylenetetrahydrofolate, which then serves as a methyl group donor for the methylation of homocysteine to methionine in a reaction catalyzed by methionine synthase. The MTHFR deficiency is the most common inborn error of folate metabolism [3].
The phenotypic expression varies from severe infantile form to late childhood/adulthood disease [4], [5], [6], [7]. The severe early
Acknowledgements
The authors are grateful to Dr. Sultan Al-Sedairy, Executive Director of the Research Centre, King Faisal Specialist Hospital and Research Centre for his support of this work. Part of this study was supported by the grant provided by Sheikh Rafik Al-Hariri (#85-0030).
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