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Iron deficiency anemia

Last reviewed: 4 Sep 2023
Last updated: 31 May 2022



History and exam

Key diagnostic factors

  • fatigue
  • dyspnea on exertion
  • pica
  • restless legs syndrome
  • nail changes
  • dysphagia
More key diagnostic factors

Other diagnostic factors

  • impaired muscular performance
  • glossitis and angular stomatitis
  • dyspepsia
  • pallor
  • hair loss
  • rectal lesion on examination
  • growth impairment
  • cognitive and behavioral impairment
  • heart failure
  • recurrent infections
Other diagnostic factors

Risk factors

  • pregnancy
  • vegetarian and vegan diet
  • menorrhagia
  • hookworm infestation
  • chronic kidney disease
  • celiac disease
  • gastrectomy/achlorhydria
  • nonsteroidal anti-inflammatory drugs (NSAID) use
  • chronic heart failure
  • preterm or low birth weight
  • infant feeding with cows' milk
  • black women and Mexican women
  • low socioeconomic status
  • obesity
  • Helicobacter pylori infection
More risk factors

Diagnostic investigations

1st investigations to order

  • hemoglobin and hematocrit
  • platelet count
  • MCV
  • MCH
  • MCHC
  • red cell distribution width
  • peripheral blood smear
  • reticulocyte count
  • serum iron
  • total iron-binding capacity
  • transferrin saturation
  • serum ferritin
  • celiac serology
  • urinalysis
  • Helicobacter pylori testing
More 1st investigations to order

Investigations to consider

  • hemoglobin electrophoresis
  • urease breath test
  • autoimmune gastritis testing
  • upper gastrointestinal endoscopy (esophagogastroduodenoscopy)
  • small-bowel biopsy
  • lower gastrointestinal endoscopy (colonoscopy)
  • CT colonography
  • transferrin receptor-ferritin index
  • bone marrow biopsy
  • monitored trial of iron
  • fecal occult blood tests
More investigations to consider

Emerging tests

  • urinary hepcidin
  • percentage of hypochromic erythrocytes
  • reticulocyte hemoglobin content
  • erythrocyte protoporphyrin

Treatment algorithm


all patients



Atul Mehta, MD

Consultant Haematologist

Lysosomal Storage Disorders Unit

Department of Haematology

Royal Free Hospital




AM has received honoraria, travel, and research grants from Sanofi/Genzyme, Shire/Takeda/Amicus and Protalix/Pfizer; all of these companies manufacture pharmaceutical therapies for the treatment of lysosomal disorders.


Dr Atul Mehta would like to gratefully acknowledge Dr Martina Murphy, Dr Marc Zumberg, and Dr Rebecca Fischer Connor, previous contributors to this topic.


MZ declares that he is medical director for NCF Diagnostics and DNA Technologies, and a consultant for Alexion Pharmaceuticals. MM and RFC declare that they have no competing interests.

Peer reviewers

Carlos Aravena, MD

Internal Medicine Instructor

Member of Evidence Based Medicine Unit

Catholic University of Chile




CA declares that he has no competing interests.

Jim Murray, MBBS

Consultant Haematologist

Clinical Haematology

University Hospital Birmingham NHS Trust




JM declares that he has no competing interests.

Ajay Kumar, MD, FACP

Medical Director

Blood Management

Cleveland Clinic




AK has received a fee for speaking about perioperative blood management from Ortho-Biotech, and has also received reimbursement from medscape.com for the education webcast of the same presentation.

  • Iron deficiency anemia images
  • Differentials

    • Anemia of chronic disease
    • Disorders of globin synthesis (thalassemias, hemoglobin E, hemoglobin C, unstable hemoglobins)
    • Sideroblastic anemias
    More Differentials
  • Guidelines

    • Guideline for the laboratory diagnosis of iron deficiency in adults (excluding pregnancy) and children
    • Guidelines for the management of iron deficiency anaemia in adults
    More Guidelines
  • Patient leaflets

    Anemia, iron deficiency

    More Patient leaflets
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