The functional connotations of iron deficiency-effect on neutrophil oxidative burst activity in preschool children.

Abstract

Iron deficiency anaemia (IDA) makes an individual prone to bacterial infections. The antimicrobial defence mechanism of neutrophils is orchestrated by Nicotinamide Adenine Dinucleotide Phosphate Hydrogen (NADPH) oxidative burst which is iron-dependent. The few previous studies documenting a decrease in neutrophil oxidative burst in iron-deficient children have been based mainly on the Nitro blue tetrazolium test (NBT). Very few studies have been conducted using the more robust flow cytometry-based dihydro rhodamine (DHR) assay in this regard worldwide and none in India.

Aim: To estimate the effect of iron deficiency on neutrophil oxidative burst activity in children under 5 years of age by flow cytometry-based dihydro rhodamine (DHR) assay and compare it with the control group.

Methods: Thirty-six children between 6 months to 5 years of age diagnosed with moderate (Hb 7-10 gm/dl) to severe (Hb <7 gm/dl) iron deficiency anaemia were selected as cases with equal number of sex/age matched controls. The peripheral blood was analyzed for hematological and biochemical parameters such as complete iron profile, serum vitamin B12, and folate levels. The oxidative burst activity of neutrophils in peripheral blood was assessed using a flow-cytometry-based Dihydrorhodamine (DHR) assay.

Results: The percentage of neutrophils showing stimulation, Mean Fluorescence Index in stimulated neutrophils, and Neutrophil oxidative index (NOI) were significantly reduced in iron deficiency anaemia patients as compared to controls. In cases, haemoglobin showed significant positive correlation with NOI and percentage of neutrophils showing stimulation.

Conclusion: To conclude, a significant decrease in neutrophil oxidative burst parameters depicts an insufficient innate immune response to pathogens and makes Iron deficiency anaemia patients more susceptible to infections, further aggravated by the severity of anaemia.