Effect of Theophylline on Serum Magnesium, Uric Acid and Nitric Oxide in Asthmatic Children

The aim of the study was to investigate the effect of theophylline on serum magnesium (Mg) and uric acid levels in children with asthma and the relationship between hyperuricemia and serum nitric oxide metabolite levels (NO2) in the same group of patients. Patients and methods: Forty four known asthmatic children who has been referred to pediatrics clinic of the National Research CenterEgypt. They were diagnosed as cases of asthma and categorized according to their asthma severity based on revised GINA Guidelines. The patients received slow release theophylline around the clock for at least one month (200-400mg /24 hours). Exclusion criteria included children with chest troubles other than bronchial asthma such as pneumonia, bronchitis, obvious clinical signs of joint disease, hypertension and cardiac disease. Twenty four age and sex matched healthy children included in the study as a control group. All the children in this study were subjected to the following: pulmonary function test, measurement of serum, Mg, uric acid and NO2. Results: There was a significant decrease in serum Mg in patients compared to controls (P=0.01). There was significant increase in serum uric acid in patients compared to controls (P= 0.01) and a highly significant increase in serum NO2 in patients compared to control (P= 0.001). There was a significant negative correlation between duration of treatment with theophylline in asthmatic children and serum Mg (r= 0.47, P= 0.03) while no significant correlation between duration of treatment with theophylline and serum uric acid (P>0.05). There was a highly significant positive correlation between serum uric acid and serum NO2 in asthmatic children (r=0.71, P= 0.001). Conclusion: Serum Mg and uric acid should be monitored in patients receiving treatment of theophylline for bronchial asthma. Hyperuricemia has been associated with increasing serum NO2 and regarded as a major risk factor associated with vascular endothelial dysfunction and related cardiovascular complications.