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Published on: July 18, 2014
Congenital methaemoglobinaemia in a 61-year-old patient with normal haemoglobin levels
K F de Geus1, A A Anas, R Franssen
1Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
Abstract:
A 61-year-old Ghanaian woman presented with dizziness and low oxygen saturations whereupon a methaemoglobin level of 24.9% was obtained. Initially it was thought to be caused by an unknown toxin. However, failure to normalise spontaneously and a short recurrence following administration of methylene blue suggested a congenital cause. Subsequently a novel variant in the CYB5R3 gene, coding for Cytochrome b5 reductase, was demonstrated. Absence of polycythaemia prompted additional analysis for a concomitant haemoglobinopathy.
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