The purpose of this study is to prospectively analyze the prevalence of SIBO in patients with Pancreatic adenocarcinoma (PDAC) and understand its association with weight loss and pancreatic resection status. Each patient will be tested for SIBO using Lactulose Hydrogen Breath Test. 100 patients with diagnosed pancreatic adenocarcinoma and clinically diagnosed weight loss will be enrolled in this study.

Small intestinal bacterial overgrowth syndrome (SIBO) is a condition defined by excessive (greater than 105 CFU/mL) or abnormal bacteria in the upper gastrointestinal tract resulting in unintentional weight loss, diarrhea, nutritional deficiencies and osteoporosis. In healthy individuals, the growth of any remaining bacteria in the stomach is limited by biliary and pancreatic secretions. The location of Pancreatic ductal adenocarcinoma (PDAC) on the pancreas head hinders these exocrine secretions from reaching the small intestine, leading to exocrine pancreatic insufficiency in pancreatic cancer patients. Patients with Pancreatic adenocarcinoma suffer from similar symptoms including weight loss, diarrhea, and nutritional deficiencies. SIBO has been linked to Exocrine Pancreatic Insufficiency or anatomical abnormalities, both consistent in PDAC patients, especially those who have undergone surgery. Post-pancreatoduodenectomy physiological changes disrupt the way enzymes are secreted, which affects exocrine and endocrine functions of the pancreas. Currently, there is a limited understanding of the prevalence of SIBO in PDAC patients.

The primary objective of this study is to assess the prevalence of SIBO in consecutive PDAC patients with clinically significant weight loss.

The secondary objective of this study is to assess the prevalence of SIBO in patients who have undergone pancreatic resection versus those who have not undergone resection.

Inclusion Criteria:

• Men, Women, and all genders
• Individuals 18 years old or older are included.
• Patients of the study investigators and team members
• Diagnosis of pancreatic ductal adenocarcinoma
• All subjects must consent to this study
• Clinically diagnosed weight loss

Exclusion Criteria:

• Minors
• Pregnant Women
• Any records flagged "break the glass" or "research opt out."
• Patients who have received treatment for SIBO in the past 3 months

Patients diagnosed with pancreatic adenocarcinoma with clinically significant weight loss.