Objective Comparison of magnesium and calcium in exhaled breath condensate (EBC) of children with asthma and gastroesophageal reflux disease (GERD).

Methods EBC was collected from a total of 53 children, aged 7–14 years (17 healthy children, 22 asthmatic children, and 14 children with GERD). EBC was collected using an EcoScreen condenser (Erich Jaeger GmbH, Hoechberg, Germany). Concentration of magnesium and calcium was determined by standardized methods on an Olympus AU400.

Results Asthmatic children have lower values of magnesium (0.030 mmol/L) than healthy children (0.051 mmol/L) and children with GERD (0.080 mmol/L). The lowest value of calcium was found in healthy children (0.046 mmol/L), in comparison with asthmatics (0.060 mmol/L) and children with GERD (0.130 mmol/L). Magnesium/calcium ratio was lower in asthmatic children (0.50) and in children with GERD (0.62) than in controls (1.11).

Conclusion These findings indicate that EBC could be used for noninvasively measurement of magnesium and calcium. Future studies should investigate clinical efficiency of magnesium and calcium determination in EBC.