A Cameron lesion is a linear erosion or ulceration of the mucosal folds lining the stomach where it is constricted by the thoracic diaphragm in persons with large hiatal hernias. The lesions may cause chronic blood loss resulting in iron deficiency anemia; less often they cause acute bleeding. Treatment of anemia with Cameron lesions includes iron supplements and proton-pump inhibitor (PPI) acid suppression. Surgical hernia repair is sometimes needed.