Sickle cell disease (SCD) is rampant in sub-Saharan Africa, a region that accounts for about two-thirds of all SCD births worldwide, and among the disease’s complications can be an imbalance in elements such as iron, an essential trace element for good health. Researchers compared key proteins associated with iron metabolism between children with SCD and their healthy siblings in Benin, a country where iron deficiency is also an important health concern.
The study, “Comparative Analysis of Iron Homeostasis in -Saharan African Children with Sickle Cell Disease and Their Unaffected Siblings,” published in Frontiers in Pediatrics, found that both children with SCD and those without showed signs of iron deficiency.
Researchers measured complete blood counts and serum concentrations of serum proteins essential to iron regulation (ferritin, transferrin, sTfR, and hepcidin) in 73 children with SCD and in 68 healthy siblings serving as a control group, and assessed the relationship between the levels of these proteins and hematological indicators.
According to the results, the mean hemoglobin (Hb) concentration was significantly lower in children with SCD than in controls. But of all the children assessed, 87.7% had Hb values below the normal distribution. Importantly, 20.4% of the children without sickle cell disease had a mean Hb concentration below the World Health Organization (WHO)’s threshold defining anemia for the same age group.
Moreover, red blood cells indices MCV, which relates to cell volume, and MCH, which relates to amount of Hb, were both below the cut-off value in 54% and 85% of children in the control group, respectively, and in 30% and 52% of those with SCD. These results can be explained by iron deficiency, a predominant condition even in healthy young children in Benin.
Furthermore, researchers found that the concentrations of transferrin, sTfR, and ferritin were significantly different between the two groups. Hepcidin concentrations, although unusually high, did not differ between the two groups. “This observation suggests that the high level of hepcidin is a common trait in Beninese children,” the researchers wrote. “We also observed a significant negative correlation between hepcidin levels and both MCH and MCV only in the SCD group and an opposite trend for sTfR and both MCH and MCV in the control group (negative correlation) and in the SCD group (positive correlation).”
Researchers believe other variables are modulating the production of hepcidin, as high levels of hepcidin under severe iron deficiency have only been reported in pathological conditions. Factors such as diet might contribute to the negative correlation observed between hepcidin and both MCH and MCV, an effect exacerbated when SCD is present.
“These results lay the foundation for a systematic evaluation of the underlying mechanisms deregulating iron homeostasis in populations with SCD or high prevalence of iron deficiency,” they concluded.