Interrelations between iron content and immune dysfunctions in frequently ill children of the Aral Sea Region

The widespread occurrence of immune-dependent diseases and disturbances in iron metabolism, as well as their co-occurrence and the impact of iron deficiency on the immune system, underscore the relevance of this study. Modern data also indicate the involvement of iron in regulating cytokine production and protein synthesis by lymphocytes. In addition to the age-related characteristics of the child’s immune system, a significant factor in the development of inadequate course of the infectious process is the disruption of immune system adaptation, which can be caused by frequent infections, other somatic diseases such as anemia, and environmental factors. The aim of this study is to assess the relationship between iron levels and immune dysfunction in children with frequent acute respiratory diseases living in the Aral Sea region. A total of 127 children, who are native residents living at the epicenter of the ecological crisis, were examined. The children’s ages ranged from 1 to 5 years old. Among them, there were 105 frequently ill children (with 6 or more episodes of acute respiratory infections per year) with iron-deficiency anemia (IDA), and 22 healthy children of the same age. All children underwent clinical examination and standard laboratory tests, including complete blood count, relative content and ratio of T and B lymphocytes, as well as the levels of pro- and anti-inflammatory cytokines (IL-2 and 4) and ferritin in the serum. According to the results of the conducted research, it was found that among frequently ill children with iron-deficiency anemia (IDA), there is a moderate positive correlation between the relative quantity of T lymphocytes and the hemoglobin level (r = +0.62), as well as a strong positive correlation with the serum iron level (r = +0.78). This indicates a significant influence of iron deficiency on the level of cellular immunity. Clinical data also indicate a higher risk of respiratory infections development in children with IDA compared to the control group. Ferritin, hemoglobin, lymphocytes, and cytokines act as positive regulators of hematopoiesis in IDA conditions and contribute to the compensation of anemia during iron deficiency replenishment.