Introduction Management of childhood asthma with inhalatory corticosteroids ICS has recently increased. Influence of systemic corticosteroids on increased renal calcium excretion is well known. Several studies in adult patients treated with ICS revealed increased urinary excretion of calcium Ca.

Aim To determine ICS influence on urine Ca exertion in children with asthma.

Methods 57 children with asthma on ICS therapy are enrolled in this study. Control group consists of 26 healthy children. There was no difference in terms of age and sex between the asthmatic and the control groups. Calciuria is measured from CaCr ratio, mgmg, in first morning spot urine. 24 hour urine was analysed in older children. Values of Ca excretion are compared before and 12weeks after introduction of ICS therapy in group I 30 children, and group II 27 children in first morning spot urine CaCr ratio mgmg, measured 12weeks after introduction of ICS therapy. The study did not include children treated with systemic corticosteroids and diuretics.

Results The morning values of CaCr were compared in the treatment group before and after applying fluticasone MannWhitney U test Z0.89 p0.37 and Z0.52 p0.61, respectively. The only significantly difference was found between the distribution of CaCr values smaller than 0.05 measured in the morning before and after applying fluticasone 0.0 29 Fisher exact test p0.02.

Conclusion Our investigation showed that middle dose fluticasone, unlike systemic corticosteroids, does not increase urinary Ca excretion. Observed hypocalcaemia might be compensatory, due to maintaining normal Ca levels in serum.