Abstract
The increasingly widespread use of novel immunosuppressive drugs may lead to unexpected infectious complications. We report a case of persistent Helicobacter pylori (H. pylori) infection that failed to respond to antimicrobial therapy in a patient receiving omalizumab (Xolair™, Genentech USA Inc., San Francisco, CA and Novartis Pharmaceuticals, Basel, Switzerland), an anti-IgE monoclonal antibody approved by the FDA for treatment of severe persistent asthma. To our knowledge, this is the first case report linking an immunosuppressive regimen containing anti-IgE biologic therapy to persistent H. pylori infection.