Table 1.
Main laboratory tests for the assessment of iron depletion
| Laboratory test |
Normal values |
||
| Conventional units | Conversion factor2 | SI units | |
| Iron status in the body | |||
| Serum iron | 50-180 g/dL | × 0.179 | 9-32 mol/L |
| Transferrin | 200-360 mg/dL | × 0.01 | 2-3.6 g/L |
| Transferrin saturation | 20%-50% | ||
| Ft | 30-300 ng/mL | × 2.247 | 65-670 pmol/L |
| sTfR1 | 0.76-1.76 mg/L | 6.4-25.7 nmol/L | |
| sTfR/log Ft | < 1 | ||
| Iron deficient red cell production | |||
| Hb | 12-16 g/dL ♀ | × 0.62063 | 7.5-10 mmol/L |
| 13-17 g/dL ♂ | 8-10.5 mmol/L | ||
| Mean corpuscular volume | 80-100 fL | ||
| Red cell distribution width | 11-15 | ||
| Mean corpuscular Hb | 28-35 pg | ||
| Hypochromic red cells | < 5% | ||
| Reticulocyte Hb content | 28-35 pg | ||
1
Normal values may differ depending on the assay used;
2
To convert the concentrations values in conventional unit into SI units multiply figures by the conversion factor;
3
In fact, although widely used, this factor allows for the calculation the molar concentration of hemoglobin subunits. Thus, the molar concentration of hemoglobin (Mw 64 kDa) is 4-fold times lower (2-3 mmol/L). Ft: Ferritin; sTfR: Soluble transferrin receptors; Hb: Hemoglobin; sTfR/log Ft: Ratio of sTfR to serum Ft.