ISSN 2398-2977      

Anemia: iron deficiency

pequis

Synonym(s): Iron deficiency


Introduction

  • Cause  Anemia: overview  :
    • Primary iron deficiency only likely in very artificial conditions in young foals on milk only diet for over 34 moths.
    • Secondary iron deficiency due to chronic blood loss (usually external bleeding such as gastric ulcers, parasites, failure of clotting, etc).
    • Anemia of chronic disease or inflammation may be thought of as a functional iron deficiency:
      • Commonest cause of mild but persistent (chronic) anemia of horses.
      • Serum iron low but total body iron in storage forms is usually normal but not available.
      • Does not respond to supplemental iron.
  • Signs: chronic anemia, reduction in performance.
  • Diagnosis: can be differentiated from other causes of anemia by hematological tests/calculations.
  • Treatment: iron supplementation.
  • Prognosis: guarded due to primary condition.

Pathogenesis

Etiology

  • Failure of iron supply (primary).
  • Very rare form seen in horses with post-surgical short gut syndrome - iron absorption takes place in mid-jejunum and so loss of large lengths can be responsible for reduction in iron absorption.  History in such cases is usually known.
  • Failure of iron availability (secondary) - much more common.

Predisposing factors

General
  • Chronic bleeding site (with external blood loss   Anemia: blood loss  )   →   loss of body iron.
  • Surgical removal of long lengths of jejunum.
  • Chronic internal infectious/inflammatory processes usually   →    mild to moderate anemia.
  • Infections such as internal abscesses (lung   Lung: abscess  , mesenteric or other usually from Bastard Strangles), pleuritis   Lung: pleuropneumonia - bacterial (pleuritis)  , peritonitis   Abdomen: peritonitis  , wounds.
  • Neoplastic disease with inflammatory responses (necrosis and secondary infections).
  • Paraneoplastic syndrome   Neoplasia: paraneoplastic syndrome  .
  • Inadequate diet with no access to pasture.

Pathophysiology

  • Iron deficiency due to chronic blood loss   Anemia: blood loss   first causes a decrease in marrow iron, later a decrease in serum iron and the typical microcytic hypochromic anemia is really a late stage finding.
  • The small size of the equine red cell makes it difficult to accurately appreciate decreases in cell size and hemoglobin content   Blood: hemoglobin (Hb) concentration  .
  • In anemia of chronic disease   Anemia: chronic disease   lack of releasing ability of transferrin makes iron unavailable to red cell production in bone marrow. 
  • Microcytic hypochromic anemia is not a common feature of anemia of chronic disease.
  • Bone marrow fails to compensate for minor reduction in life span of erythrocytes.
  • Impaired erythrocyte production due to failure to access iron and sequestration of older red cells by  reticulo-endothelial system results in a slowly progressive usually modest anemia.

Timecourse

  • Slow.
  • Progressive.

Diagnosis

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Brommer H & von Oldruitenborgh-Oosterbaan M M (2001) Iron deficiency in stabled Dutch Warmblood foals.  J Vet Intern Med 15, 482-485 PubMed.
  • Means R T & Krantz S B (1992) Progress in understanding the pathogeneis of the anaemia of chronic disease. Blood 80, 1639-1647 PubMed.
  • Harvey J W, Asquith R L, Sussman W A et al (1987) Serum ferritin, serum iron and erythrocyte values in foals. Am J Vet Res 48, 1348 PubMed.
  • Smith J E, Ciprinao J E, DeBowes R et al (1986) Iron deficiency and pseudo-iron deficiency in hospitalized horses. JAVMA 188, 285 PubMed.

Other sources of information

  • Carlson G P (2002) Diseases of the Hematopoietic and Hemolymphatic Systems. In: Large Anim Intern Med. Ed: Smith B P. Chapter 35. Mosby.
  • Sellon D C (1995) Diseases of the Haemopoietic System. In: The Horse: diseases and Clinical Management. Eds: Kobluk C N, Ames T R & Geor R J. W B Saunders, USA.

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!

 
 
 
 

To show you are not a Bot please can you enter the number showing adjacent to this field

 Security code