Differences in Salivary Microbiome in Patients with Gastroesophageal Reflux Disease

The relationship between the oral and systemic health has been well established. The oral microbial composition may be able to explain links between the two. Gastroesophageal reflux disease (GERD) is a chronic gastrointestinal disease that increases acidity in the oral cavity. Changes in pH level in the oral cavity may modify the oral microbiome that may influence periodontal health. The use of proton pump inhibitor (PPI) drugs to manage GERD may reverse the change. The aim of our study was to evaluate the microbial differences between patients with untreated GERD and those without GERD. Additionally, the periodontal status of patients with GERD and the effect of PPI on the microbiome were assessed. Stimulated saliva samples were collected from subjects at UIC College of Dentistry pre-doctoral clinics. From saliva samples, microbial DNA was extracted, V1-V3 region of the 16 rRNA gene was amplified, and the DNA was sequenced. QIIME2.0 was used to group and measure numbers of DNA sequence reads. The Human Oral Microbiome Database (HOMD) was used to map the bacterial taxa. In our study, untreated GERD patients showed lower levels of certain salivary microbiome as compared to healthy controls: Prevotella melaninogenica, Prevotella pallens, Leptotrichia, and Solobacterium moorei. On the other hand, GERD patients treated with PPI showed minimal differences in salivary taxa compared to healthy controls without disease. There was no difference in periodontal status of patients with untreated GERD and without GERD. The correlation between the presence of GERD and changes in the oral microbiome may help better understand the oral manifestations of this disease.