High prevalence of gastrointestinal symptoms in patients with primary Sjogren's syndrome cannot be attributed to pancreatic exocrine insufficiency

Introduction Pancreatic exocrine insufficiency (PEI) results in maldigestion of fat, leading to steatorrhea, malabsorption and weight loss. Sjogren's syndrome (SS) is a chronic autoimmune rheumatic disease with unknown etiology. The exocrine pancreas and the salivary glands are functionally and histologically comparable, and pancreatic dysfunction in SS has been hypothesized. Methods Patients were recruited from the Department for Rheumatology at the Karolinska University Hospital in Stockholm, Sweden, between June and December 2019. PEI was assessed by fecal elastase-1 (FE-1) and C-13-mixed triglyceride breath test (C-13-MTG-BT). The presence and severity of gastrointestinal symptoms were assessed by a well-established and validated survey based on a seven-point Likert scale. Results Fifty-seven patients with primary SS were included in the study, comprising 92% females with a median age of 63 years. In total, 87% of SS patients were tested for FE-1 and all had normal results. All patients who underwent a C-13-MTG-BT had a normal cumulative C-13-exhalation. Compared to the control group, significantly more patients suffered from gastrointestinal (GI) symptoms (p < .01). The same number of patients noted moderate to severe loose bowel movements or constipation (38%). Eleven GI symptom parameters were compared to controls and the highest odd ratios were noted for the following moderate to severe symptoms: bloating, feeling of incompletely emptied bowel after defecation and abdominal pain relieved by bowel action. Conclusion In our study, most SS patients suffered from irritable bowel syndrome (IBS)-like GI symptoms that could not be attributed to PEI.