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Zinc and copper in serum and induced sputum of patients with allergic rhinitis and allergic asthma

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Abstract

Background: Zinc was shown to have protective effect on the respiratory system, so it may play a role in allergic airway diseases. The aim of our study was to measure zinc and copper levels in serum and induced sputum in patients with allergic rhinitis and patients with allergic asthma. Methods: We measured concentrations of zinc and copper in serum and in supernatant of induced sputum in 21 patients with allergic asthma, in 13 patients with allergic rhinitis and in 10 control subjects. Results: We have found decreased levels of zinc in serum of patients with allergic asthma and in patients with allergic rhinitis. Furthermore, levels of zinc in serum in patients with allergic asthma were lower than in patients with allergic rhinitis. Concentrations of zinc in supernatant of induced sputum were lower in asthmatics than in control subjects and rhinitics, but this difference was not statistically significant. There was no significant difference in concentrations of copper in serum and in sputum between asthmatics, rhinitics and control subjects. We have also found a positive linear correlation between zinc concentrations in serum and sputum in the group of control subjects, in patients with allergic asthma and in male patients with allergic rhinitis. Conclusion: We conclude that zinc deficiency was confirmed both in patients with allergic asthma and in patients with allergic rhinitis.

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