Many patients experiencing acute gastrointestinal bleeding (GIB) require iron supplementation to treat subsequent iron deficiency (ID) or iron-deficiency anemia (IDA). Guidelines regarding management of these patients are lacking. We aimed to identify areas of unmet need in patients with ID/IDA following acute GIB in terms of patient management and physician guidance. We formed an international working group of gastroenterologists to conduct a narrative review based on PubMed and EMBASE database searches (from January 2000 to February 2021), integrated with observations from our own clinical experience. Published data on this subject are limited and disparate, and those relating to post-discharge outcomes, such as persistent anemia and re-hospitalization, are particularly lacking. Often, there is no post-discharge follow-up of these patients by a gastroenterologist. Acute GIB-related ID/IDA, however, is a prevalent condition both at the time of hospital admission and at hospital discharge and is likely underdiagnosed and undertreated. Despite limited data, there appears to be notable variation in the prescribing of intravenous (IV)/oral iron regimens. There is also some evidence suggesting that, compared with oral iron, IV iron may restore iron levels faster following acute GIB, have a better tolerability profile, and be more beneficial in terms of quality of life. Gaps in patient care exist in the management of acute GIB-related ID/IDA, yet further data from large population-based studies are needed to confirm this. We advocate the formulation of evidence-based guidance on the use of iron therapies in these patients, aiding a more standardized best-practice approach to patient care.

The use of red blood cell concentrates must follow the dictates of a rational indication. To further ensure this, the "Cross-Sectional Guidelines for Therapy with Blood Components and Plasma Derivatives" 1 of the German Medical Association, published in 2009 and last revised in part in 2014, were systematically revised in 2020. This article presents them.

Anemia is considered a public health issue and is often caused by iron deficiency. Iron-deficiency anemia (IDA) often originates from blood loss from lesions in the gastrointestinal tract in men and postmenopausal women, and its prevalence among patients with gastrointestinal bleeding has been estimated to be 61%. However, few guidelines regarding the appropriate investigation of patients with IDA due to gastrointestinal bleeding have been published.

To review current evidence and guidelines concerning IDA management in gastrointestinal bleeding patients to develop recommendations for its diagnosis and therapy.

Five gastroenterology experts formed the Digestive Bleeding and Anemia Workgroup and conducted a systematic literature search in PubMed and professional association websites. MEDLINE (via PubMed) searches combined medical subject headings (MeSH) terms and the keywords "gastrointestinal bleeding" with "iron-deficiency anemia" and "diagnosis" or "treatment" or "management" or "prognosis" or "prevalence" or "safety" or "iron" or "transfusion" or "quality of life", or other terms to identify relevant articles reporting the management of IDA in patients over the age of 18 years with gastrointestinal bleeding; retrieved studies were published in English between January 2003 and April 2019. Worldwide professional association websites were searched for clinical practice guidelines. Reference lists from guidelines were reviewed to identify additional relevant articles. The recommendations were developed by consensus during two meetings and were supported by the published literature identified during the systematic search.

From 494 Literature citations found during the initial literature search, 17 original articles, one meta-analysis, and 13 clinical practice guidelines were analyzed. Based on the published evidence and clinical experience, the workgroup developed the following ten recommendations for the management of IDA in patients with gastrointestinal bleeding: (1) Evaluation of hemoglobin and iron status; (2) Laboratory testing; (3) Target treatment population identification; (4) Indications for erythrocyte transfusion; (5) Treatment targets for erythrocyte transfusion; (6) Indications for intravenous iron; (7) Dosages; (8) Monitoring; (9) Indications for intravenous ferric carboxymaltose treatment; and (10) Treatment targets and monitoring of patients. The workgroup also proposed a summary algorithm for the diagnosis and treatment of IDA in patients with acute or chronic gastrointestinal bleeding, which should be implemented during the hospital stay and follow-up visits after patient discharge.

These recommendations may serve as a starting point for clinicians to better diagnose and treat IDA in patients with gastrointestinal bleeding, which ultimately may improve health outcomes in these patients.