Helicobacter: Worming Its Way into All Sorts of Extragastric Systems

Some microorganisms cause diseases distant or separate from the primary site of infection by interfering with different biologic processes. H. pylori seems to one of them, and the past year has elucidated many of the Helicobacter pylori infection's far-reaching effects. A review published in the September 2016 issue of Helicobacter does an exceptional job of covering recent research into other conditions associated with this infection.

Traditionally considered a gastric infection associated with ulcers and acid reflux, the infection has numerous extragastric implications. Many clinicians are aware that it can cause or contribute to idiopathic thrombocytopenic purpura, sideropenica anemia, and vitamin B₁₂ deficiency.

New evidence indicates that H. pylori seems to increase risk for cardiovascular disease, especially if the patient is infected for 5 years or more. Exposure to this bacterial infection also seems to increase risk and magnitude of cognitive impairment in patients with Alzheimer's disease.

Beyond that, H. pylori has been implicated in progression of glaucoma, and central serous chorioretinopathy. It has also been associated with periodontal disease, and high rates of the infection in some populations have been linked to diabetes mellitus (especially type 2 diabetes) and metabolic syndrome. Some studies even indicate that infected individuals have lower level of high-density lipoprotein, and higher blood pressures, total cholesterol, HbA_1c, and fasting blood glucose.

H. pylori's systemic effects are expansive, and clinicians need to raise the index of suspicion when patients report symptoms suggestive of this infection.