Abstract

Background/Aim: Gastro-esophageal reflux has been suggested to be associated with several pulmonary complications such as asthma, and post-transplant bronchiolitis obliterans (BO). Pepsin or bile salts in the sputum is shown to be an optimal molecular marker of gastric contents macro/micro aspiration. In this study, we investigated sputum pepsin as a marker of micro-aspiration in sulfur mustard (SM) exposed cases compared to healthy controls. Materials and Methods: In a case controlled study, 26 cases with BO and 12 matched healthy controls were recruited and all cases were symptomatic and their exposure to SM was previously documented during Iran-Iraq conflict. Pepsin levels in sputum and total bile acids were measured using enzymatic assay. The severity of respiratory disorder was categorized based upon the spirometric values. Result: The average concentration of pepsin in sputum was higher in the case group (0.29 0.23) compared with healthy subjects (0.13 0.07; P 0.003). Moreover, the average concentration of bile acids in the sputum cases was not significantly different in comparison to the controls ( P = 0.5). Conclusion: Higher pepsin concentrations in sputum of SM exposed patients compared with healthy control subjects indicate the occurrence of significantly more gastric micro-aspiration in SM exposed patients.