A simplified diagnostic pathway for the differential diagnosis of iron deficiency anaemia and anaemia of chronic disease

Introduction Iron deficiency anaemia (IDA) and anaemia of chronic disease (ACD) are common causes of anaemia with similar clinical and laboratory features. IDA is caused by low iron stores while ACD is due to iron-restricted erythropoiesis occurring in inflammatory states. Differential diagnosis requires analysis of multiple biochemical and haematological parameters. IDA can occur simultaneously to ACD (mixed aetiology). It is essential that true iron deficiency is identified, as these patients will require iron therapy. This preliminary study investigated whether hepcidin, the master regulator of iron homeostasis, in conjunction with reticulocyte haemoglobin equivalent (RetHe) has the potential to differentiate IDA from ACD, and to exclude IDA in patients with mixed aetiology. Methods Hepcidin concentration (measured using a commercially available ELISA method), RetHe, and iron parameters along with C-reactive protein (CRP) were analysed in 77 Gastroenterology patients with anaemia in a secondary care setting. Results Receiver operator characteristic (ROC) analysis showed that hepcidin at an optimal cut-off concentration of 46ng/ml. Identifying true IDA in mixed aetiology patients could be achieved by RetHe analysis and applying an optimal cut-off of <30pg. Conclusion Hepcidin, in conjunction with RetHe, offers a new simplified diagnostic pathway for differential diagnosis of IDA and ACD, thereby reducing the diagnostic turnaround time and allowing appropriate treatment of patients with a true iron deficiency.

Automated summary

This study investigated the potential of using hepcidin in conjunction with reticulocyte haemoglobin equivalent (RetHe) to differentiate between iron deficiency anaemia (IDA) and anaemia of chronic disease (ACD), as well as exclude IDA in patients with mixed aetiology. The results showed that hepcidin, along with RetHe, offers a new simplified diagnostic pathway for differential diagnosis of IDA and ACD, reducing the diagnostic turnaround time and allowing appropriate treatment of patients with true iron deficiency.