Helicobacter pylori (H. pylori) is a gram-negative spiral bacterium that colonizes the human gastric epithelia. Within the gastrointestinal tract, H. pylori infection may lead to gastric ulcers, gastritis, mucosa-associated lymphoid tissue lymphoma or stomach cancer. Beyond the gut, H. pylori infection results in systemic inflammatory cascades that can lead to autoimmune diseases, chronic heart disorders, and autoimmune thyroid disorders. Indeed, H.pylori infection has been shown to correlate with severity of coronary artery disease. Elevated levels of IgG to H. pylori may be indicative of past or reactivating infection.