Patients with inflammatory bowel disease (IBD) and those with chronic obstructive pulmonary disease (COPD) experience disrupted iron homeostasis and cellular Fe accumulation, often accompanied by anemia and non-anemic Fe deficiency which negatively impacts the quality of life in this patient population, and significantly burdens the healthcare system. The pathogenesis of iron deficiency in IBD patients is multifactorial, including intestinal bleeding, malabsorption, and inadequate oral intake. While oral iron is safe, affordable, and easy to administer, patients often suffer from intolerable gastrointestinal side effects, and particularly in IBD patients, oral iron may increase inflammation and contribute to flares. Intravenous (IV) iron is considered first-line treatment for patients with active disease, severe anemia, oral iron intolerance, and erythropoietin requirements. Fe content and iron-binding molecules, including ferritin, lipocalin 2, and lactoferrin, are all increased in the lung tissue, sputum, bronchoalveolar lavage fluid, and alveolar macrophages of patients with COPD, and increases are proportional to disease severity and lung function. Increased cellular Fe may be both pathogenic and protective.
Methods: We examined the hospital records of all patients admitted for a non-infectious event, who had an underlying diagnosis of IBD or COPD. Patients treated with intravenous iron (IV Fe) and/or transfusions of red blood cells (RBC) for iron deficiency anemia (IDA) were compared to a control group of untreated patients. We compared severity of disease, duration of hospital stay, number and types of infections during hospitalization, and pathogens causing infections. Data collection included demographic information, Fe indices (iron, transferrin, ferritin, iron saturation (TSAT), hemoglobin (Hgb), and hematocrit (Hct), hepcidin, Fe products / formulations, and dosages, RBC timing and amount, and administration of Fe chelators. Risk factors for infection were assessed by multivariate logistic regression.Results: IDA was common in hospitalized patients with IBD and COPD. Hgb and Hct increased significantly with IV Fe or RBC (or both) treatment. Correction of the Fe deficiency in IBD and COPD patients with IV Fe can improve IDA but may result in an increased risk of infection and an increased hospital stay.