W1062 Gastric Emptying in Adult Patients With Cystic Fibrosis

Abstract

Introduction: It has been established that patients with cystic fibrosis (CF) have a high prevalence of gastroesophageal reflux (GER). Increased acid reflux is most common in CF, however a small subgroup of CF patients has increased weakly acidic reflux. The presence of bile acids (BA) in saliva in almost half of CF patients suggests pathological duodenogastro-esophageal reflux (DGER). The aim of this study was to quantify DGER and BA in saliva in adult CF patients. Methods: 14 adult CF patients [median age 29 (18-58), 5 male] were evaluated using combined 24 hrs impedance-pH and Bilitec monitoring. After an overnight fast, an impedance-pH catheter and Bilitec probe were inserted trans-nasally in the esophageal body with the pH and Bilitec sensors located 5 cm above the lower esophageal sphincter (LES). To avoid Bilitec artifacts patients consumed liquid meals. During the study day, lung function assessesment (FEV1 and FVC) and saliva samples were obtained for BA measurement. Results: 5/14 (35%) of the CF patients had increased DGER. 10 patients had isolated DGER events, mostly during daytime but 3 patients had predominantly nocturnal DGER. There was a significant correlation between DGER and total acid exposure (p<0.0001, r=0.85) and total bolus exposure (p=0.03, r=0.57). There was a significant correlation between DGER and the number of acid reflux episodes (p=0.01, r=0.62). Patients with increased DGER had a higher proximal extent of reflux (number of reflux events reaching up to 15 cm above the LES) compared to those with no DGER [17 (9-35) vs. 5 (3-12), p= 0.03]. There was a negative correlation between DGER and proportion of non-acid reflux events (p=0.03, r=-0.59). DGER was unaffected by age, BMI or history of sputum bacterial colonization. Bile acids were present in saliva of 8 CF patients. The concentration of BA in saliva was slightly higher in patients with increased DGER compared to patients without DGER but the difference did not reach statistical significance. There was no significant correlation between severity of DGER and lung function. Conclusion: Increased DGER is present in 1/3 of adult CF patients. DGER is clearly associated with increased acid reflux and high proximal extent of reflux. Presence of BA in saliva is common in adult patients with CF and its concentration tended to be higher in CF patients with increased DGER, however, a clear correlation between severity of DGER and BA concentration in saliva could not be established.