RET-He represents the haemoglobin equivalent of reticulocytes measured in pg and is a way of diagnosing and monitoring iron deficiency anaemia.
RET-He is calculated from the RET-Y parameter, which is the mean value of forward scattered light within the reticulocyte population, measured on Sysmex analysers.
RET-He has been shown to be clinically equivalent of the CHr measured on Siemen's Advia instruments.
RET-He is the fastest way to detect changes in iron status.
Since red blood cells have a 120 day lifetime, detecting iron deficiencies and changes in the iron status of erythropoiesis is only possible relatively late using the classical haematological parameters (Hb, MCV and MCH).
With acute or chronic inflammation it is not easy to distinguish a functional iron deficiency from a classical iron deficiency (insufficient iron intake, deficient iron resorption, haemorrhaging, or increased iron demand) if using classical serum tests.
The RET-He, used in combination with ferritin and soluble transferrin receptor, can give a complete assessment of iron stores and functional erythropoiesis.
RET-He can be used to monitor response to iron therapy in patients with iron deficiency anaemia or those receiving erythropoietin therapy.
Using RET-He: RET-He alone gives information on the current bioavailability of iron a low value means iron is lacking or iron is not bioavailable for erythropoiesis. It is often used together with ferritin. Since ferritin is increased during the acute phase of diseases, inflammation should be ruled out, e.g. by CRP.
- a high or normal ferritin value together with a low RET-He value can suggest functional iron deficiency
- low ferritin values together with low RET-He suggest a classic iron deficiency.
- RET-He is used for monitoring erythropoietin (EPO) and/or IV iron therapy. If the value increases it indicates the therapy is having a positive effect.