Validation of Breath Tests in Diagnosing Small Bowel Bacterial Overgrowth

NCT ID: NCT00872092

Last Updated: 2009-03-31

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 22 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 1997-10-31
• Study Completion Date: 1998-09-30

Brief Summary

Normally the gastrointestinal tract is only sparsely colonized with bacteria. The normal flora of the duodenal or jejunal aspirate contains no more than 10^5 bacteria per milliliter. Small bowel bacterial overgrowth (SBBO) is defined as a pathologically increased number of bacteria or the presence of colonic flora in the proximal intestine. The reasons for this condition are manifold, ranging from diabetic neuropathy to surgical bypass. SBBO is frequent in elderly people. Therapy is targeted at correcting the underlying small bowel abnormalities that predispose to the condition and at providing appropriate antibiotic therapy. The symptoms and signs of SBBO can be reversed with this approach. However, in many patients the conditions predisposing to SBBO persist life-long, once present. This suggests that noninvasive, sensitive diagnostic tools with high specificity are required. Bacterial culture of upper intestinal content is considered the diagnostic gold standard. However, since endoscopic harvesting of duodenal or jejunal fluid is difficult and invasive, indirect tests such as breath tests have been advocated as diagnostic tools. Hydrogen breath tests are commonly employed since the substrates can be easily obtained and the measurement is simple. Hydrogen is formed when carbohydrates are fermented in the intestine. Breath hydrogen analysis allows a separation of metabolic activity of the intestinal flora from that of the host, since no known hydrogen production occurs in mammalian tissue. The hydrogen breath test most often used in routine clinical practice uses glucose. However, the utility of this test is mostly limited by its low sensitivity, because there are "nonproducers" in up to 25% of the subjects tested. The investigators have developed a stable isotope breath test using 13C-labeled lactose-ureide. Glycosyl-ureides are condensation products of reducing sugars and urea in aqueous acid. Lactose-[13C]ureide has been used to investigate oro-caecal transit time because it resists digestion by small intestinal enzymes and is hydrolyzed by bacterial enzymes in the large intestine. A number of studies have described the use of this substrate in adults and children. The aim of the present study was to investigate the lactose-[13C]ureide breath test in subjects with suspected SBBO and to compare its results with the results of the glucose hydrogen breath test. Microbiological analyses of upper intestinal bacterial cultures were used as gold standard to identify SBBO.

Conditions

Malabsorption Syndromes

Keywords

small bowel; bacterial overgrowth

Study Groups

Breath test

Subjects with suspected SBBO

Stable-isotope labeled lactose ureide breath test

Intervention Type: OTHER

2 g 13C-labeled lactose ureide orally

Interventions

Stable-isotope labeled lactose ureide breath test

2 g 13C-labeled lactose ureide orally

Intervention Type: OTHER

Other Intervention Names

Lactosyl ureide

Eligibility Criteria

Inclusion Criteria

• Suspected small bowel bacterial overgrowth

Exclusion Criteria

• Age < 18 years
• Antibiotic therapy

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University Hospital, Bonn

OTHER

Sponsor Role: lead

Responsible Party

University of Bonn - Germany

Principal Investigators

Heiner K. Berthold, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Bonn

Locations

University of Bonn

Bonn, , Germany

Countries

Germany

Other Identifiers

BTO-0001

Identifier Type: -

Identifier Source: org_study_id