TBA (16S110)

Small Intestinal Bacterial Overgrowth in Post Oesophagectomy and Gastrectomy Patients


M. Brennan1, P. Lawlor1, T. Moran1, C. Donohoe2, N. Ravi2 and JV. Reynolds2, GI Function Unit, St. James Hospital1, Department of Surgery, Trinity Centre for Health Science St. James Hospital, Dublin 8, Ireland2


GI Function Unit St James's Hospital


Small Intestinal Bacterial Overgrowth (SIBO) may contribute to GI Symptoms and malnutrition in post oesophagectomy and gastrectomy patients.


The aim of this study was to look at the incidence of Small Intestinal Bacterial Overgrowth and create an optimal Hydrogen Breath Test (HBT) protocol with the hope of improving patient compliance and reducing clinic waiting times. Factors such as lifestyle, multimodal therapy, tumour morphology, and gender were analysed in relation to positive HBT results in this patient group.


Following a strict 12 hour fast and pre-procedure instructions, the patient’s HBT was conducted. A glucose solution was consumed and samples were taken every 15 minutes over a two hour period.


A total of 87 patients were tested for SIBO using glucose substrate. Of these, 53% were positive for SIBO. When broken into time frames, 45% were positive when tested within 1-6 months of surgery. 73% were positive for SIBO when tested within 7-12 months of surgery and 50% were positive when tested for SIBO 1 year post surgery. Of those patients positive for glucose breath tests, 96% had a positive rise within 75 minutes, 93% within 60 minutes, 85% within 45 minutes, 59% within 30mins and 24% within 15 minutes. The average time that patients were likely to show a positive result was 36.52 minutes. Lifestyle factors including smoking and drinking habits as well as BMI had a statistically significant effect on the outcome of HBT results. Those patients who had a history of previous malignancy and post-operative complications showed a higher tendency towards a positive glucose HBT result, but this was not statistically significant. In addition to the above statement, patients who had a longer post-operative hospital stay following their gastrectomy or oesophagectomy also tended to be positive for HBT using glucose substrate.


It is recommended that the testing protocol for glucose Hydrogen Breath Testing is reduced from 2 hours to 60 minutes for this group of patients if there is no rise in hydrogen levels. It is also recommended that symptomatic patients who have a negative Hydrogen Breath Test be referred for a SeHCAT test.