In the present study, we found significantly elevated serum sTfR levels in patients with IDA or ADC/IDA compared to patients with ACD or “other anemia.” These results are consistent with previously published studies demonstrating that sTfR is a useful biomarker to detect iron-depleted anemic states and to differentiate effectively between IDA and ACD/IDA on the one hand and ACD on the other hand [13, 14, 23, 24]. Here, TFRC is linked to anemia.