Review article: infective complications of therapeutic gastric acid inhibition.

Gastric acid secretion has a non-specific bactericidal action which contributes to gastrointestinal defence mechanisms against micro-organisms. Therapeutic inhibition of acid secretion with histamine H2 receptor antagonists and proton pump inhibitors might therefore be expected to predispose to infection. This article reviews clinical reports of infection occurring during therapeutic gastric acid inhibition, and assesses the risk of infection incurred by such treatment. Non-typhoid salmonelloses, Campylobacter infections, local candidiasis, and possibly Strongyloides hyperinfections may be more prevalent after acid inhibitory treatment, but concurrent impairment of other gastrointestinal defence mechanisms may be necessary to permit infection.