Leucocytosis-induced artefactual hypoglycaemia in the setting of chronic neutrophilic leukaemia.

A man in his late 70s with newly diagnosed chronic neutrophilic leukaemia with marked leucocytosis was found to have recurrent low plasma glucose levels on routine bloodwork. Nevertheless, he did not exhibit any signs or symptoms of hypoglycaemia, and capillary blood glucose measurements taken at the same time were within normal limits. Time-dependent plasma glucose concentration decline with delayed processing confirmed the suspected diagnosis of artefactual hypoglycaemia secondary to hyperleucocytosis. This phenomenon is caused by excessive in vitro glycolysis, which can be mitigated by rapid sample processing or the use of tubes containing glycolysis inhibitors. This case report adds to the existing body of evidence on artefactual hypoglycaemia with the aim of raising awareness of this entity among healthcare professionals. In asymptomatic individuals with low glucose measurements, the possibility of spurious results should be considered prior to initiating further diagnostic work-up.