The role of the host versus the environment in duodenal ulcer disease.

Gastric functions can be understood only in the context of a network including the brain gut axis, neuro-endocrine and paracrine mechanisms and growth factors. These host factors including parietal cell sensitivity (PCS) may well interact with an important environmental factor, Helicobacter pylori (Hp), and help to explain its actions. The aim of this study was to investigate PCS related to Hp status and duodenal ulcer (DU). PCS was assessed by constructing dose-response curves after pentagastrin and calculating the D50. Five groups of patients were studied: I) active DU, Hp pos. (8); II) history of DU, Hp pos. (8); III) asymptomatic Hp pos. (8); IV) asymptomatic Hp neg. (10); V) DU on maintenance H2 blocker therapy, Hp pos. (20). PCS was repeated after Hp eradication. PCS was lowest in group IV, and in Hp pos. groups, was significantly higher, with insignificant differences among them, irrespective of DU. PCS declined significantly after Hp eradication. Group V showed an insignificant decline in PCS during treatment, not preventing recurrence. A higher PCS in Hp infection irrespective of DU, declining after eradication, suggests that this may be a reversible epiphenomena related to Hp infection. This may offer an explanation as to why DU develops only in some subjects with Hp, suggesting the importance of the host in the pathogenesis of DU.