Contribution of the laboratory in hypoglycemia diagnosis induced by insulin administration in a 2-year-old girl

We report the case of a 2 year-old child presented to the emergency department following a seizure. The child was hypotonic and examination was unremarkable but laboratory tests confirmed a severe hypoglycaemia. The insulin level, inappropriately high for the glycemia and the peptide C undetectable suggested exogenous hyperinsulinism. We conclude that the hypoglycaemia was likely the result of Munchhausen syndrome by proxy. The specificity of two immunoassays used (Elecsys Roche and IRMA CisBio) for the synthetic analogues of insulin explains the discrepancy between the insulin levels obtained but was crucially useful to the approach of the cause of the hypoglycaemia.