[Use of iron in nephrology: Results of a French practical survey]

The French-speaking Society of Nephrology, Dialysis and Transplantation conducted, in 2018, a survey among French nephrologists into their iron prescribing habits for patients with chronic kidney disease stages 3 to 5 before dialysis. The results show that 73% of nephrologists use intravenous iron before dialysis stage. When a patient has gastrointestinal symptoms under oral iron therapy, only 48% of nephrologists use intravenous route. The starting thresholds for iron are for 78% of nephrologists a transferrin saturation <20% and for 80% a serum ferritin <100 μg/L. Only 14% start iron when a transferrin saturation <25% or higher and 29% start iron when serum ferritin <200 μg/L or higher. High dosages of iron (500 and 1000 mg) are used by 58% of nephrologists. Finally, about 30% of nephrologists refer to various barriers to intravenous iron prescription, such as cost, unavailability of intravenous iron in their facility or lack of day hospital unit. The correction of iron deficiency without anemia remains controversial. It is performed by only 43% of nephrologists. These results show an improvement of the practices compared to a 2006 survey. However, they indicate a sub-prescription of iron compared to the European recommendations which recommend a starting threshold of iron of transferrin saturation <25% and ferritinemia <200 μg/L in anemic patients not treated with erythropoietin-stimulating agents.