Among the diagnostic strategies for validating the provisional diagnosis of iron deficiency anaemia (IDA) [1] one parameter worth including is the response to a diagnostic trial of iron replacement therapy [2,3,4], which could be utilised even in subjects with normocytic iron deficiency anaemia [5]. However, in the context of coexisting chronic inflammation, failure to respond to a trial of oral iron does not rule out IDA because inflammatory hepcidin elevation would impair iron absorption [6]. In order to overcome this disadvantage a two-stage diagnostic trial has been proposed.