Unexpected high HbA1c results due to an unusual haemoglobin variant: an important clinical lesson

Introduction The measurement of glycated haemoglobin (Hb), reported as HbA1c, is recommended for the screening, diagnosis and monitoring of diabetes mellitus. HbA1c measurement usually provides an assessment of an individual’s glycaemic control over the previous 2–3 months and correlates with the development of diabetic complications. Standardisation of results attempts to ensure both intra- and inter-assay agreement so that an individual’s glycaemic control can be accurately monitored. Historically, standardisation was performed based on the Diabetes Control Complications Trial (HbA1c reported as a percentage), but more recently based on the International Federation of Clinical Chemistry (reported as mmol/mol). However, despite robust approaches towards measurement standardisation, it is recognised that HbA1c results might not necessarily provide a true reflection of glycaemic control. HbA1c can be falsely lowered by conditions that shorten erythrocyte survival or decrease mean erythrocyte age (eg, acute blood loss or haemolytic anaemia) irrespective of the assay method.
Source: Postgraduate Medical Journal - Category: General Medicine Authors: Tags: Adverse drug reactions Source Type: research