[Helicobacter pylori-associated diseases]

Abstract

This article summarizes the main conclusions of the studies presented at Digestive Disease Week this year (2015) related to Helicobacter pylori infection. Despite the undeniable widespread reduction in the prevalence of H. pylori infection, developing countries continue to have substantial infection rates. The prevalence of clarithromycin, metronidazole and quinolone resistance is markedly higher in most countries and continues to rise. Although H. pylori eradication reduces the incidence of gastric adenocarcinoma, it does not completely prevent its development; the presence of precancerous lesions--intestinal atrophy and metaplasia--is associated with a higher risk of developing this neoplasm, despite H. pylori eradication. The use of molecular diagnostic methods (polymerase chain reaction) in faecal samples could allow non-invasive evaluation of the antibiotic susceptibility of H. pylori. The effectiveness of standard triple therapy is clearly insufficient and continues to decrease. The effectiveness of sequential therapy in recent studies is lower than initially described and consequently this treatment cannot be recommended in clinical practice. Concomitant therapy is more effective and simpler than sequential therapy. In penicillin-allergic patients, quadruple therapy with bismuth is the treatment of choice in our environment. After the failure of standard triple therapy, second-line therapy with levofloxacin is effective and, moreover, is simpler and better tolerated than quadruple therapy with bismuth. Quadruple therapy with a proton pump inhibitor, bismuth, levofloxacin and amoxicillin is an effective (≥ 90% eradication), simple and safe second-line therapy if triple or quadruple therapy without bismuth (sequential or concomitant) fails to eradicate the infection. The new-generation quinolones, such as moxifloxacin or sitafloxacin, could be useful in second- or third-line rescue eradication therapy. Even after the failure of 3 eradication treatments, a fourth empirical rescue therapy (with rifabutin) can be effective. The management of H. pylori infection by European gastroenterologists is widely heterogeneous, and their eradication rates are generally unacceptable. In addition, there is a clear discrepancy between consensus document recommendations and clinical practice in primary care. The incidence of H. pylori reinfection is very low in the most developed regions, but is high in developing countries.

Keywords: Clarithromycin; Claritromicina; Cáncer gástrico; Diagnosis; Diagnóstico; Gastric cancer; Helicobacter pylori; Metronidazol; Metronidazole; Resistance; Resistencia; Tratamiento; Treatment.