Severe Anemia Management

Immediate Clinical Priorities

The American Gastroenterological Association recommends that patients with severe anemia (Hb 5 g/dL) should undergo urgent transfusion and comprehensive gastrointestinal investigation, rather than tumor marker testing 1, 3
Transfusion of 2-3 units of packed red blood cells is recommended immediately, given the severe anemia and likely symptomatic status, with each unit expected to raise hemoglobin by approximately 1.5 g/dL 3, 2

The European Society for Medical Oncology suggests that complete blood count with reticulocyte count should be performed to assess bone marrow response 2, 4
Iron studies (ferritin, transferrin saturation, serum iron, total iron-binding capacity) are recommended to confirm iron deficiency 1, 2, 4
Peripheral blood smear should be evaluated to assess red blood cell morphology 1, 4
Vitamin B12 and folate levels should be checked to exclude other nutritional deficiencies 2, 4
Renal function (creatinine, eGFR) should be assessed to evaluate for chronic kidney disease 2, 4
Inflammatory markers (C-reactive protein) should be evaluated to assess for chronic disease 3, 4

The American College of Gastroenterology recommends that both upper endoscopy (esophagogastroduodenoscopy) and colonoscopy must be performed in patients with severe anemia 1
Upper endoscopy with duodenal biopsies should be performed to evaluate for gastric cancer, peptic ulcer disease, angiodysplasias, and coeliac disease 1
Colonoscopy should be performed to evaluate for colorectal cancer and other colonic lesions 1

If gastrointestinal evaluation is negative and iron deficiency is confirmed, consideration should be given to small bowel evaluation with capsule endoscopy or enteroscopy to identify small bowel angiodysplasias or other lesions 1
Reassessment for non-gastrointestinal blood loss (menstruation in premenopausal women, blood donation, NSAID use) is recommended 1
Evaluation for malabsorption disorders should be performed if coeliac disease was not adequately excluded 1