Candida-associated Gastric Ulcer Until Yesterday, Today, and from Tomorrow --- In Quest of the Etiology ---

Corresponding Author: Kenji Sasaki, Home Medical Care Supporting Clinic Sendai, 30-3, Kabanomachi, Wakabayashi Ward, Sendai, Miyagi, 984-0037, Japan, Tel: +81-80-1817-8414; E-mail: [email protected] Abstract Candida-associated gastric ulcer, though formerly thought to affect only debilitated persons, has been reported to occur in apparently healthy individuals. Though had been reported to demonstrate nothing but nonspecific endoscopic features, the disease occasionally exhibits an apparently typical finding designated a candidarium. The natural history of the disease had been unknown but the ulcer is shown to not only occur but also recur in a different site with a different shape in a non-diabetic, Helicobacter pylori (H. pylori)-negative patient without antecedent ulcers or history of the lesions, who has not been given non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, or antineoplastic agents, which implies that Candida is no innocuous bystander but an etiologic perpetrator. Immune deficiency has recently been reported in relation to candidiasis, which is considered to explain the cause of intractable or recurrent Candidaassociated gastric ulcer. In the oropharyngeal field, Candida albicans has recently been shown to secrete a hitherto unknown cytolytic peptidepore-forming toxin (PFT), candidalys in, into a pocket in the epithelium which penetrates into and to activate mitogen-activated protein kinase (MAPK)/MAPK phosphatase 1(MPK1)/c-Fos pathway, triggering release of damage as well as immune cytokines. While the PFT, exerting an effect even on the adjacent cells, directly injures the tissue with damage cytokines, immune counterpart activates polymorphonuclear leukocytes(PMN) to eventually terminate inflammation, which results in restoring the fungus to the commensal state or eradicating it. Since it cannot be negated that such a phenomenon occurs in the gastric mucosa, a theoretically strong possibility has come up that the socalled Candida-associated gastric ulcer is actually Candida-induced ulcer. Therefore, the disease should be reinvestigated in the light of the recent immunological, microbiological, and molecular biological findings.