[Peptic ulcer: a failure of the defense mechanisms of the gastroduodenal mucosa?].

Peptic ulcer is an heterogeneous and multifactorial disease. Secretion of acid/pepsin is a critical permissive factor in gastroduodenal peptic ulceration. Therapy of this disease has been based mostly on this principle. The sole presence of the aggressive factor, acid/pepsin, is not enough to explain peptic ulceration. Mucosal defense (resistance) is another critical factor involved in pathogenesis of this disease. Defects in some gastroduodenal defense mechanisms have been found in patients with peptic ulcer disease, such as: synthesis and release of prostaglandins, mucus and bicarbonate secretions, and the luminal hydrophobic layer. Both the dictum "no acid-no ulcer" and the coroliary "normal healing-no ulcer" seems to be valid. Correction of a possible deficiency in mucosal defense/resistance may be a useful and practical principle is management of patients with peptic ulcer disease.