The main aim of this thesis was to determine the clinical usefulness of breath tests with 13C-labelled substrates to diagnose small intestinal malabsorption. To this end we studied patients with coeliac disease, one of the most common causes of small intestinal malabsorption in the industrialised world today.
The study showed that the radioactive 14C-D-xylose breath could be replaced by the 13C-D-xylose breath test without loss of diagnostic accuracy. The 4-hour 13C-D-xylose breath test had satisfactory sensitivity and specificity for untreated coeliac disease. The breath test index improved in treated coeliac disease, but was not normalized. A novel 1-hour 13C-sorbitol breath test was also developed. We found that this test can be used to stratify patients into high, medium and low risk for coeliac disease. The 13C-sorbitol breath test performed significantly better than the H2-sorbitol breath test. The 13C-sorbitol breath test improved in treated coeliac disease, but was not normalized.
We conclude that 13C-labelled breath tests are sensitive tools for small intestinal malabsorption. Further studies are needed to determine the value of 13C-labelled breath tests in follow-up of coeliac disease.
List of papers. Papers I-III are removed from the thesis due to copyright restrictions.
Tveito K, Brunborg C, Sandvik L, Løberg EM, Skar V.
13C-xylose and 14C-xylose breath tests for the diagnosis of coeliac disease.
Scand J Gastroenterol. 2008;43(2):166-173.
Tveito K, Brunborg C, Bratlie J, Askedal M, Sandvik L, Lundin KE., Skar V.
Intestinal malabsorption of D-xylose: comparison of test modalities in patients with coeliac disease.
Scand J Gastroenterol. 2010 Nov;45(11):1289-94
Tveito K, Hetta AK, Askedal M, Brunborg C, Sandvik L, Løberg EM, Skar V.
A novel one-hour 13C-sorbitol breath test versus the H2-sorbitol breath test for assessment of coeliac disease.
Scand J Gastroenterol. 2009;44(7):813-19.
Tveito K, Hetta AK, Askedal M, Løberg EM, Skar V.
Follow-up of coeliac disease with the novel one-hour 13C-sorbitol breath test versus the H2-sorbitol breath test. Submitted version, published in:
Scand J Gastroenterol. 2011;46(7-8):837-43. Copyright 2011 Informa Healthcare.