Albertine Donker

Chapter 4 172 Supplemental Table 3. Continued B. Heterozygous TMPRSS6 defect age (years) Hb (g/L) MCV (fL) TSAT (%) Ferritin (µg/L) Hepcidin (nM) TSAT/hepcidin (%/nM) Patient ID 18 At presentation 30 12.1 67 np np np np At diagnosis, no treatment (intravenous iron in the past) 47 12.4 70 8.0 131 7.0 1,1 Patient ID 19 35 10.3 78 6 52 np np At 3 mnths of oral iron 35 11.4 80 np 57 np np At 6 mnths of oral iron 35 12.7 91 12.5 125 5.9 2.1 Patient ID 20 At presentation 41 7.9 62 2.8 3.0 np np On intravenous iron 41 12.6 89 179 np np np Patient ID 21 At presentation 34 9.7 68 4 22 np np At 3 mnths on oral iron 34 10.6 71 np 38 np np At 6 mnths on oral iron 34 13.0 normal 20 293 7.7 2.6 Quantitative data of response to oral and/or iv iron were not available of all patients. a In patient 8 a MRI of the liver was performed because of increased ferritin levels, which showed a Liver Iron Content (LIC) of 60 µmol (3.35 mg) Fe/g tissue (1.5 Tesla MRI, Siemens Magnetom Vison Plus, reference value <36-µmol/g tissue). 2 Normal LIC concentrations are up to 1.8 mg Fe/g dry weight tissue with levels up to 7 mg Fe/g dry weight tissue seen in carriers of genetic hemochromatosis without apparent adverse effect. Thus, the LIC in patient 8 is not suspect for severe iron overload. Moreover, the combination of elevated ferritin and relatively low TSAT indicates iron sequestration in the RES, that is considered to be less harmful compared to parenchymal iron loading. 3,4