Karen O'Brien is a pediatric nurse practitioner in the Gastroenterology and Nutrition department at MUSC. She earned her master's degree in nursing in pediatric acute and chronic care from the University of Pennsylvania in Philadelphia in 1993. , She is board certified as a primary care pediatric nurse practitioner by the American Nurses Credentialing Center. Karen has many years of experience working as a primary care pediatric nurse practitioner and now specializes in pediatric gastroenterology. She is a member of the Association of Pediatric Gastroenterology and Nutrition Nurses., , Karen takes care of patients with general gastrointestinal disorders including; celiac disease, failure to thrive, functional gastrointestinal disorders, constipation, encopresis, gastroesophageal reflux, eosinophilic esophagitis, and childhood obesity. She has a particular interest in pediatric nutrition.