Iron and ferritin concentrations in exhaled breath condensate of children with asthma

Maintenance of iron homeostasis is of utmost importance for the respiratory system physiology and pathophysiology. Local iron deficiency or accumulation may result in particular respiratory function impairment. The aim of the present study was to find out whether iron and ferritin could be determined in exhaled breath condensate (EBC) of healthy children and children with asthma. Oxidative stress was verified by determination of EBC superoxide dismutase (SOD) activity, and the airway inflammatory process by determination of exhaled nitric oxide (F(E)NO). EBC was collected from 39 children (22 healthy children as a control group and 17 asthmatics) using an EcoScreen condenser. Iron, ferritin, and SOD were determined on optimization and validation for low concentrations. In comparison with a control group, asthma patients had a statistically significantly lower iron concentration (p = 0.0001) and higher SOD catalytic activity (p = 0.0160), with no significant difference in ferritin levels (p = 0.5252), although percentile values indicated elevated ferritin concentration in about half of asthma patients. F(E)NO values were significantly higher in the asthma group (p = 0.0047). This preliminary study demonstrated the possibility of determining iron and ferritin concentrations and SOD activity in EBC, and a significant difference in EBC iron and SOD between asthma patients and healthy children.