Erroneous glucose recordings while using mutant variant of quinoprotein glucose dehydrogenase glucometer in a child with galactosemia

We report a 2-month-old child with galactosemia and falsely high glucose readings with a glucometer using mutant variant of quinoprotein glucose dehydrogenase (MutQ-GDH) chemistry. Potentially fatal hypoglycemia could have been induced in the child if insulin infusion had been initiated as per glycemic management protocol. Even though, the product information with the glucometer carries warning regarding interference by high galactose levels, the awareness regarding this interaction is generally poor in many practice settings. Although, false readings have been reported with glucose dehydrogenase pyrroloquinoline quinone (GDH-PQQ) glucometers, to our knowledge this is the first case report of a falsely high glucose reading due to high galactose in a proven case of galactosemia with a glucometer using the MutQ-GDH chemistry (a modified GDH-PQQ chemistry). Our experience has prompted us to write this case report and we suggest avoiding these glucometers in neonates and infants when a metabolic disease is suspected.