Helicobacter pylori in intensive care: why we should be interested.

Helicobacter pylori is estimated to infect over 50% of the world's population, the majority of whom are asymptomatic. Although most research to date has focused on local gastroduodenal disease manifestations, the potential impact of H. pylori infection and the associated chronic active inflammation on systemic disease processes is now being explored. This review addresses three aspects of emerging importance regarding H. pylori in intensive care medicine: acute gastric stress ulceration, nosocomial infection, and the potential modulatory effect on the systemic stress response. The role of H. pylori in acute stress ulceration remains uncertain, but it is unlikely to have the same major aetiological role as in peptic ulcer disease. The pathogenesis of both acute stress ulceration and H. pylori gastritis suggest overlapping mechanisms of gastric mucosal damage and H. pylori may augment stress ulceration incidence and severity. Nosocomial infection of both staff and patients with H. pylori has been suggested by serological studies, and increased H. pylori infection has been reported in intensive care staff. This has significant short- and long-term health implications and also raises questions regarding the efficacy and implementation of routine infection control precautions in intensive care. Finally, H. pylori infection has been linked with the pathogenesis of many extra-intestinal diseases, but the evidence is weak and the relationship between H. pylori and systemic diseases remains controversial. However, the potential for H. pylori to modulate systemic disease processes, particularly the systemic stress response in critical illness, is both theoretically plausible and therapeutically tantalising and requires further investigation.