Lower Plasma Soluble Transferrin Receptor Range in Healthy Indian Pediatric Cohort as Compared to Asian and Western Data

Iron Status of Preadolescents Without Clinical Pallor Attending a Tertiary Care Hospital in South India- A Cross-Sectional Analytical Study

OBJECTIVES

To determine the prevalence of Iron Deficiency (ID) in children without clinical pallor using serum ferritin and the new parameters, soluble transferrin receptor (sTfR) & the ratio of sTfR/log10 serum ferritin (sTfR-F index), as suggested by WHO. Also to assess whether these new parameters could individually predict the presence of ID.

METHODS

Consecutive 230 healthy children aged 9-11 y without clinical pallor underwent estimation of Hemoglobin (Hb), C-Reactive Protein (CRP), serum ferritin, sTfR, and sTfR-F index levels in their blood. The abilities of the sTfR and sTfR-F index in predicting ID were determined by comparing with the gold standard (normal CRP and less serum ferritin), plotting Receiver-operating characteristic (ROC) curve, and noting the area under the curve (AUC).

RESULTS

The blood reports of 114 boys and 106 girls (total = 220) were available for analysis. Overall, 57 (31 girls, 26 boys) children had ID; among children with low CRP, 45 had ID, as suggested by low serum ferritin levels. Among children with high CRP, 12 had evidence of ID as evidenced by elevated sTfR and/or sTfR-F index. The positive predictive values of both sTfR and sTfR-F were low (32.9% and 35.9%, respectively) than the negative predictive values (85.6% and 95.3%, respectively).

CONCLUSIONS

The proportion of children identified to have ID using serum ferritin, sTfR, and sTfR-index was 25.9%. sTfR and/or sTfR-F index are unlikely to be ideal individual predictors of ID.

Iron and iron-related proteins in COVID-19

COVID-19 can cause detrimental effects on health. Vaccines have helped in reducing disease severity and transmission but their long-term effects on health and effectiveness against future viral variants remain unknown. COVID-19 pathogenesis involves alteration in iron homeostasis. Thus, a contextual understanding of iron-related parameters would be very valuable for disease prognosis and therapeutics.Accordingly, we reviewed the status of iron and iron-related proteins in COVID-19. Iron-associated alterations in COVID-19 reported hitherto include anemia of inflammation, low levels of serum iron (hypoferremia), transferrin and transferrin saturation, and high levels of serum ferritin (hyperferritinemia), hepcidin, lipocalin-2, catalytic iron, and soluble transferrin receptor (in ICU patients). Hemoglobin levels can be low or normal, and compromised hemoglobin function has been proposed. Membrane-bound transferrin receptor may facilitate viral entry, so it acts as a potential target for antiviral therapy. Lactoferrin can provide natural defense by preventing viral entry and/or inhibiting viral replication. Serum iron and ferritin levels can predict COVID-19-related hospitalization, severity, and mortality. Serum hepcidin and ferritin/transferrin ratio can predict COVID-19 severity. Here, serum levels of these iron-related parameters are provided, caveats of iron chelation for therapy are discussed and the interplay of these iron-related parameters in COVID-19 is explained.This synopsis is crucial as it clearly presents the iron picture of COVID-19. The information may assist in disease prognosis and/or in formulating iron-related adjunctive strategies that can help reduce infection/inflammation and better manage COVID-19 caused by future variants. Indeed, the current picture will augment as more is revealed about these iron-related parameters in COVID-19.