Detection of HFE Haemochromatosis in the clinic and community using standard erythrocyte tests

Detection of HFE Haemochromatosis (HH) is challenging in the absence of clinical features. HH subjects have elevated erythrocyte parameters compared to those without HH, but it remains unclear how this could be applied in clinical practice. Thus, we determined the sensitivity, specificity and clinical utility of erythrocyte parameters in 144 HH subjects with (n = 122) or without (n = 22) clinical and/or biochemical expression of iron overload, 1844 general population controls, and 700 chronic disease subjects. For both expressing and nonexpressing HH subjects, the mean pre- and post-phlebotomy values of mean cell volume (MCV) and mean cell haemoglobin (MCH) were always significantly higher when compared to all other groups and demonstrated excellent diagnostic utility for detection of HH in men and women (AUROC 0.83-0.9; maximal sensitivity and specificity 82% and 78%) using cut-off values for MCV > 91 fL or MCH > 31 pg, respectively. Between 34 and 62% of all HH subjects would be detected, and <4% of all non-HH subjects would undergo unnecessary testing, if those with MCV or MCH values > 94 fL or 32.2 pg, respectively, were evaluated.