The use of parotid gland activity analysis in patients with gastro-esophageal reflux disease (GERD) and bulimia nervosa.

PURPOSE

In patients with vomiting or reflux episodes, specific pathognomic signs may occur in the oral cavity. The significance of salivary gland activity in this type of disorder is a matter of dispute. The purpose of this study was to evaluate the parotid gland activity of patients with bulimic type eating disorder (group B) compared with patients affected by gastro-esophageal reflux (GERD) (group A) and healthy control subjects (group C).

MATERIAL AND METHODS

Parotid saliva was collected during the clinical examination by means of a modified Lashley cap under unstimulated and stimulated conditions and the flow rate was determined. The concentrations of Na+, K+, Ca+ (mmol/l) were determined by a colorimetric photometry method (Effox 5053, Eppendorf, Germany). Buffering capacity as a concentration of bicarbonates (mmol/l) and the pH, were measured by an automatic ion-selective electrode (ABL TM 520, Radiometer, Denmark). For the statistical analyses Kruskal Wallis one way ANOVA on Ranks with Dunn's method all pairwise multiple comparisons procedures were used with significance set at p < or = 0.05.

RESULTS

The results showed that the flow rates in the subjects in group A and B were significantly lower than in the controls. There were also significant differences in the concentration of sodium, with the lowest level in group B, and calcium where the highest level occurred in group A.

CONCLUSIONS

Since patients may deny frequent vomiting (bulimia) or are unaware of the reflux (GERD) the changes in electrolyte levels revealed by this study appear to be of use in the diagnosis of these conditions.