The diagnostic test Peptest detects pepsin in saliva and is used as a quick and easy measure of the gastric reflux responsible for gastroesophageal reflux and extra-esophageal reflux into laryngopharynx. There is evidence that airway reflux is responsible for the etiology or exacerbation of a number of respiratory conditions.
This study evaluated 352 patients with a number of respiratory diseases in the presence of pepsin in a saliva sample. It was shown that 283 patients (80%) were pepsin positive.
Patients in this study have a significantly higher prevalence of pepsin than the standard control population. Reflux over the upper esophageal sphincter and the presence of pepsin exacerbate the severity of the pulmonary disease or reduce the effects of pulmonary therapy.