Duodenal epithelial thymidine uptake in patients with duodenal ulcer or endoscopic duodenitis

The Yale-Affiliated Gastroenterology Program. A personal note

The Yale-Affiliated Gastroenterology Program provides an effective combination of tutorial and group dynamics and may be the model for need-based training of subspecialists in communities. If the present university centers work in partnership with quality community programs, the consequent university program may offer more pertinent education and proceed in a more appropriate direction for the field of gastroenterology than that of the currently accepted agenda.

Increased PCNA/cyclin index correlates with severity of duodenitis defined by histological criteria

The proliferative activity of crypt epithelial cells was studied in 64 duodenal biopsies using immunohistochemistry and proliferating cell nuclear antigen (PCNA)/cyclin monoclonal antibodies in alcohol-fixed paraffin-embedded sections. A positive correlation between duodenitis as defined by histological criteria and increased mean percentage of PCNA positive crypt cell nuclei (PCNA index) was found. The mean PCNA index in normal mucosa was 11.8 +/- 2.7% (mean +/- SD), in mild (grade 1) duodenitis 17.3 +/- 3.9%, in moderate (grade 2) 30.6 +/- 6.9%, and in severe (grade 3) duodenitis 41.1 +/- 8.5%. The inclusion of PCNA index, which is easily measured in paraffin-embedded sections, in the existing histopathological grading systems of duodenitis may improve their clinical relevance.

Aetiology of ulcers

It seems that duodenal and gastric ulcers are caused by environmental ulcerogens, which are probably infectious or chemical. The reasons for individual susceptibility to these ulcerogens have not been defined and, indeed, it is not yet certain that the effects are not essentially random. Abnormalities of function of the mucosae of the upper alimentary tract do not appear to be necessary or sufficient for the production of ulcers. The two principal clinical aspects of ulcer disease--the tendency to form chronic mucosal wounds and the tendency of the wounds to recur during many years--point to, but cannot yet be explained in terms of, failure of the processes involved in wound repair. More specifically, it is not known whether there is interference with the processes involved in normal mucosal repair or whether there is failure of the repair processes. When these problems are closer to solution, it will perhaps be possible to assess how environmental factors influence ulcerogenesis.

Epithelial cell proliferation in human fundic and antral mucosae. Influence of superselective vagotomy and relationship with gastritis

Epithelial cell proliferation in the fundic and antral mucosae was studied in 19 duodenal ulcer patients, 11 patients having undergone fundic superselective vagotomy for duodenal ulcer, and 10 controls. This was achieved through in vitro incorporation of tritiated thymidine in mucosal biopsies and radioautography. Except for increased fundic mucosal height, duodenal ulcer patients did not differ from controls for all parameters studied. In vagotomized patients, as compared to the other two groups, the labeling index was significantly enhanced in the innervated antral mucosa where atrophic gastritis developed, but there was no change in the labeling index and no worsening of mucosal inflammation in the denervated fundic mucosa. The only abnormality in the latter was a striking expansion, towards the surface, of the proliferative area within the fundic pit. The labeling indices and the degree of gastritis in gastric mucosae are significantly correlated in control and duodenal ulcer patients. After superselective vagotomy, this correlation still existed in antral mucosa (r = 0.88, P less than 0.001) but not in fundic mucosa. If findings in antral mucosa, after superselective vagotomy, seemed related to gastritis lesions, those in fundic mucosa were not and may indicate an alteration due to the vagotomy per se.

Duodenitis

"Duodenitis" remains a controversial area in clinical medicine. This review discusses the various methods of diagnosis (histology, radiology, endoscopy) and concludes that "endoscopic duodenitis" is a definite clinical entity. Studies are presented on the changes in duodenitis in relation to peptic ulcer disease, and it is concluded that "endoscopic duodenitis" is unlikely to be the cause of symptoms unless accompanied by a peptic ulcer.