Authors: Mishkin D, Boston FM, Blank D, Yalovsky M, Mishkin S.

Institution: Department of Medicine, McGill University, Montreal, Quebec, Canada.

Summary: The aim of this study was to determine whether an indirect noninvasive indicator of proximal bacterial overgrowth, the glucose breath test, was of diagnostic value in inflammatory bowel disease.

Twenty four of 71 Crohn's disease patients tested had a positive glucose breath test. No statistical conclusions could be drawn between the Crohn's disease activity index and glucose breath test status. Of patients with radiologic evidence of small bowel stricture(s), 96.0% had a positive glucose breath test, while only one of 46 negative glucose breath test patients had a stricture. The positive and negative predictive values for a positive glucose breath test as an indicator of stricture formation were 96.0% and 97.8%, respectively.

This correlation was not altered in Crohn's disease patients with fistulae or status postresection of the terminal ileum. The data in ulcerative colitis were nondiagnostic. In conclusion, the glucose breath test appears to be an accurate noninvasive inexpensive diagnostic test for small bowel stricture(s) and secondary bacterial overgrowth in Crohn's disease.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11911333&query_hl=36

Authors: Mishkin B, Yalovsky M, Mishkin S.

Institution: Royal Victoria Hospital, Faculty of Medicine, McGill University, Montreal, Quebec, Canada.

Objectives: The aim of this study was to compare the prevalence of lactose malabsorption (LM) in various subgroups of inflammatory bowel disease patients with controls matched for age, sex, and ethnic origin.

Results: A control group at low ethnic risk had a prevalence of LM of 29.2% compared with 40.0% in CD (p < 0.025) and 13.3% of ulcerative colitis patients (p < 0.025). No significant differences were observed in comparable groups at moderate risk for LM. Irrespective of ethnic origin, 68.1% of patients with CD limited to the terminal ileum were lactose malabsorbers compared with 43.5% of patients with Crohn's colitis (p < 0.05). Additional analysis according to anatomical location indicated that Crohn's disease of the proximal small bowel (duodenum, jejunum), terminal ileum, terminal ileum plus colon, and colon alone were associated with a prevalence of LM of 100, 68.1, 54.5, and 43.5% respectively.

Conclusions: In patients at low ethnic risk there is a statistically significant increase in the prevalence of LM in CD patients and a decreased prevalence in ulcerative colitis compared with controls.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9219788&query_hl=52