Folate Levels in Patients With Small Intestinal Bacterial Overgrowth (SIBO)

Abstract

Introduction: Patients with dyspepsia often pose a diagnostic challenge given their symptoms are nonspecific such as bloating, flatulence, distention, and abdominal pain. The symptoms of dyspepsia in small intestinal bacterial overgrowth (SIBO) occur due to an overproliferation of the gut flora, which is manifested by maldigestion. Bacteria within the small intestine ferment sugars and release gaseous byproducts which can be measured through breath testing, the current cornerstone of noninvasive diagnosis of SIBO. These bacteria may also produce nutrients, including folate, which can then be absorbed by the host. We hypothesize that elevated folate levels in patients with maldigestive symptoms may indicate SIBO as the contributor to those symptoms, and indicate earlier testing and treatment. Methods: Data was collected on all patients with a xylose breath test performed between January 2005 and December 2013 at Montefiore Medical Center, an urban hospital. Patients were enrolled in the study if a folate level was available in our electronic medical record within the preceding year of breath testing. Comparisons of folate levels were analyzed with a 2-sample Z test and likelihood ratio calculations. Results: Seventy patients diagnosed with SIBO based on breath testing and 14 patients negative for SIBO were enrolled, each with a folate level in the preceding year. Fifty percent of patients with SIBO and 28% of patients negative for SIBO had an elevated folate level (p value=0.0659). In our study, patients with an elevated folate level were 1.75 times more likely to have SIBO than patients with a normal folate level (95% CI=0.74-4.14). Conclusion: In patients with symptoms of maldigestion, there is a trend towards folate levels being more elevated in those with diagnosed SIBO as compared to those without the disease. In this study of patients who underwent breath testing, those with elevated folate levels were more likely to be diagnosed with SIBO. Based on our results, folate may be useful in suggesting an underlying diagnosis of SIBO in patients with dyspepsia.