Parotid gland function in children with cystic fibrosis and child control subjects

Abstract

Citric acid stimulated parotid saliva took approximately 4 min to reach an activated state, with flow rate, amylase, calcium and sodium values tending to rise and potassium and inorganic phosphate to fall during this period. In comparisons between CF and control saliva, calcium concentrations were highly statistically significantly elevated in the CF saliva. Flow rate, amylase, and sodium values of both CF and control saliva showed wide standard deviations about the means, and although higher in the CF patients, were only minimally statistically significantly different. Potassium and inorganic phosphate concentrations were similar in the two groups of subjects, with significantly elevated inorganic phosphate only in the 2 to 4 min period. In the 6 to 10 min activated secretion period, there were statistically significant positive correlations between flow rate and calcium, flow rate and sodium, amylase and calcium, amylase and potassium (control), amylase and phosphate (CF), and sodium and calcium. Significant negative correlations were found between flow rate and potassium (CF), flow rate and inorganic phosphate (control), sodium and potassium, potassium and calcium (CF), and inorganic phosphate and calcium (CF). Although calcium and amylase correlated significantly, a substantial amount of calcium was independent of amylase (0.68 mM in control and 0.96 mM in CF saliva).