Serum ferritin to detect iron deficiency in children below five years of age

Background Iron deficiency (ID) anemia impacts the cognitive and motor development of children until the age of 10 years, despite receiving iron therapy. Early detection of ID is recommended and serum ferritin has been proposed as an alternative indicator for ID detection.Objective To assess the diagnostic accuracy of serum ferritin for detecting ID in children below five years of age.Methods This cross-sectional, diagnostic study was conducted in primary health care centers in Yogyakarta and Bantul. Hemoglobin (Hb), serum ferritin and soluble transferrin receptor (sTfR) levels were performed on children aged 6–59 months. A sTfR level of ≥ 8.2 mg/L was used to define iron deficiency. The best cut off point for serum ferritin level use as a diagnostic tool was determined by receiver operator curve.Results The prevalence of ID was 32%. Mean hemoglobin levels in iron deficient and healthy children were 11.7 (SD 0.5) g/dL and 12.2 (SD 0.7) g/dL, respectively. The sensitivity, specificity, and positive predictive value (PPV) of serum ferritin (<12 ug/L) were 17%, 93%, and 56%, respectively. Using a cut off of <32.4 ug/L, serum ferritin had sensitivity of 62.1% and specificity of 50.8%.Conclusions The diagnostic value of serum ferritin levels is modestly capable of detecting ID. Therefore, serum ferritin should not be used as an alternative indicator for detecting ID in children below five years of age.