Iron deficiency in children with cyanotic congenital heart disease: prevalence and clinical implications

Background. Children with cyanotic congenital heart disease (CCHD) are at increased risk of iron deficiency anemia (IDA) due to chronic hypoxia-induced erythropoiesis, which elevates iron demand and may mask anemia despite high hemoglobin levels. This study aimed to determine the prevalence and hematologic profile of IDA in pediatric patients with CCHD. Methods. A cross-sectional study was conducted over two years at a tertiary care hospital, enrolling 42 children (<18 years) with confirmed CCHD. Clinical data were collected, and laboratory investigations included complete blood count (CBC) and iron profile (serum iron, ferritin, transferrin saturation, total iron-binding capacity). Iron deficiency was defined as serum ferritin ≤15 ng/ml and/or transferrin saturation ≤16%. Results. The majority of participants were between 1 and 6 years of age (52%). The overall prevalence of IDA was 33% (14/42). Compared to children without IDA, those with IDA had significantly lower mean hemoglobin (10.99 ± 1.13 vs. 14.35 ± 1.07 g/dl, p < 0.001), red blood cell count (4.30 ± 0.96 vs. 4.96 ± 0.79 million/µl, p = 0.020), and hematocrit (44.53 ± 12.63 vs. 52.30 ± 7.90%, p = 0.022). No significant differences were observed in MCV, MCH, MCHC, or RDW. Cyanotic spells were not significantly associated with IDA (p = 0.71). Conclusion. IDA was observed in one-third of children with CCHD. Hemoglobin concentration alone may not accurately reflect iron status in these patients. Regular screening using red cell indices and biochemical iron parameters is essential for early detection and timely supplementation to reduce potential complications and long-term morbidity.