What biological markers could be used for diagnosis and monitoring of nitrous oxide abuse?

Emeline Gernez ¹Angèle Lucas ¹Jean-Paul Niguet ²Anas Bennis ³Remy Diesnis ⁴, Alastair J Noyce ⁵, Guillaume Grzych ¹

Eur J Neurol. 2024 Mar;31(3)

We have carefully read the article published in the European Journal of Neurology entitled "How to distinguish Guillain-Barré syndrome from nitrous oxide-induced neuropathy: a 2-year, multicenter, retro-spective study". Our aim is to offer suggestions for the use of vitamin B12 as a biomarker of nitrous oxide (N2O) intoxication:

• Clinical presentation varies in cases of N2O poisoning

• The pathophysiology of N2O exposure shows that vitamin B12 is not a suitable biomarker.

• Plasma homocysteine is a marker of recent N2O consumption

• Plasma MMA is a marker of the clinical severity of N2O abuse.

• In the context of N2O consumption, a combination of biomarkers is recommended.

Link to article: https: //pubmed.ncbi.nlm.nih.gov/38117540/