Authors: Furusu H, Murase K, Nishida Y, Isomoto H, Takeshima F, Mizuta Y, Hewlett BR, Riddell RH, Kohno S.

Institution: Second Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan. murasek@net.nagasaki-u.ac.jp

Background and Aims: Recent studies have shown that focal active gastritis seems to be the typical gastric pathology in Crohn's disease. The aim of this study was to compare the incidence of focal active gastritis, Helicobacter pylori infection and distribution of gastric mast cells and macrophages in patients with Crohn's disease, ulcerative colitis and H. pylori gastritis without inflammatory bowel disease.

Method: Patients with histologically confirmed Crohn's disease (n = 25) or ulcerative colitis (n = 25) and control patients without inflammatory bowel disease (n = 25) were included in this study. Biopsy specimens were obtained from the antrum and corpus of each patient, and stained with hematoxylin and eosin and immunostained using antibodies to tryptase (AA1) and CD68. The number of mast cells and macrophages located in the lamina propria was determined.

Conclusions: Our findings indicated that the diagnosis of focal active gastritis, using immunostain for mast cells and macrophages, is the histological hallmark of gastric Crohn's disease. Macrophages might be associated with the formation of focal active gastritis in patients with Crohn's disease.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12063959&query_hl=106

Authors: Oberhuber G, Hirsch M, Stolte M.

Institution: Department of Clinical Pathology, University of Vienna, Medical School, Austria. Georg.Oberhuber@akh-wien.ac.at

Comment: A better definition of gastric mucosal histology in Crohn's disease permits a more accurate estimation of the frequency of upper gastrointestinal tract involvement in Crohn's disease.

In a retrospective study of 792 patients with known Crohn's disease the incidence of lesions associated with the disease was determined in the duodenum, duodenal bulb, and gastric antrum and body mucosa. Crohn's disease was identified histologically in the antrum in 41.5%, in the body in 37.1%, in the duodenum in 12.1%, and in the duodenal bulb in 13%. In a further 15% and 17.4% of cases, Crohn's disease of the duodenum and duodenal bulb, respectively, was suspected. The positive predictive value of focal gastritis in patients undergoing upper endoscopy and not yet known to have Crohn's disease is as high as 94%.

Thus, a high proportion of Crohn's disease patients show upper gastrointestinal tract involvement, with the major involvement in the antrum. Focal gastritis suggesting Crohn's disease turned out to have a high positive predictive value in patients not known to have Crohn's disease at the time of gastroscopy.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9463587&dopt=Abstract