Helicobacter pylori and non-steroidal anti-inflammatory drugs: lone agents or partners in crime?

A variety of mechanisms are responsible for the gastric and duodenal mucosal injury known to result from the consumption of non-steroidal anti-inflammatory drugs (NSAIDs). Many of these mechanisms may be influenced by coexistent infection with Helicobacter pylori. However, evidence of increased risk from NSAIDs in patients with this bacterium is contradictory. While some authors have reported that symptoms, severity and prevalence of mucosal damage are higher in H. pylori-positive individuals taking NSAIDs than in those who are H. pylori negative, others have noted no significant difference. Reasons for this conflict may include the age of the subjects studied, duration of treatment, toxicity of the NSAID employed and pathogenicity factors related to different strains of H. pylori.