Helicobacter pylori infection has been associated with many intestinal and extraintestinal infections. It has been linked with many neurological and ophthalmological disorders including cerebrovascular diseases, migraine, Alzheimer's disease, epilepsy, Parkinson's disease, multiple sclerosis, peripheral neuropathies, glaucoma, and non-arteritic anterior ischemic optic neuropathy. The pathophysiological mechanisms could involve various immunological processes in response to an infectious agent or different antigens released during tissue destruction resulting in activation of cellular and humoral immunity; platelet activation and aggregation; different vasoactive and inflammatory substances; reactive oxygen species; and apoptotic processes. The long-term effects of H pylori eradication therapy on the course of these disorders still need to be explored and warrant further studies.
