Protein-losing enteropathy caused by Lawsonia intracellularis in a weanling foal.

Abstract: A 5-month-old Morgan filly was presented to the Atlantic Veterinary College with a history of lethargy, fever, depression, anorexia, and dependent ventral edema. Diagnostic tests revealed severe inflammation, hypoproteinemia, and thickened small intestinal loops. Protein-losing enteropathy caused by Lawsonia intracellularis was diagnosed and treated successfully with erythromycin-rifampin.
Publication Date: 2003-03-07 PubMed ID: 12619560PubMed Central: PMC340023
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This research reports a case of a young horse suffering from protein-losing enteropathy, a condition causing protein loss through the gastrointestinal tract, caused by a bacterial infection (Lawsonia intracellularis). The case was successfully treated using erythromycin-rifampin.

Case Overview

  • The case involved a 5-month-old Morgan filly which was brought into the Atlantic Veterinary College. The horse showed various symptoms including lethargy, fever, depression, refusal to eat (anorexia), and ventral edema, which is fluid accumulation in the lower parts of the body.

Testing and Diagnosis

  • Several diagnostic tests were carried out which showed signs of severe inflammation. In addition, the horse had hypoproteinemia, a condition characterized by low levels of protein in the blood. This indicated possible malnutrition or a disease process causing loss or underproduction of protein.
  • Imaging studies detected thickened small intestinal loops, a common sign of protein-losing enteropathy. The combined results therefore led to the diagnosis of protein-losing enteropathy.
  • Furthermore, the causative agent of the disease was identified as Lawsonia intracellularis, a bacterium that affects different animal species causing proliferative enteropathy, a disease characterized by thickening of the intestinal wall due to abnormal cell growth.

Treatment & Outcome

  • The infected horse was treated with erythromycin-rifampin, a combination of antibiotics typically used to combat bacteria inside cells. Noticeably, Lawsonia intracellularis is an intracellular bacterium making the treatment approach highly appropriate.
  • Following the treatment, the condition of the horse improved hence indicating the effectiveness of the chosen treatment strategy.

Cite This Article

Bihr TP. (2003). Protein-losing enteropathy caused by Lawsonia intracellularis in a weanling foal. Can Vet J, 44(1), 65-66.


ISSN: 0008-5286
NlmUniqueID: 0004653
Country: Canada
Language: English
Volume: 44
Issue: 1
Pages: 65-66

Researcher Affiliations

Bihr, Tanja P
  • Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island C1A 4P3.

MeSH Terms

  • Animals
  • Anti-Bacterial Agents / therapeutic use
  • Antibiotics, Antitubercular / therapeutic use
  • Diagnosis, Differential
  • Drug Therapy, Combination / therapeutic use
  • Erythromycin / therapeutic use
  • Female
  • Gram-Negative Bacterial Infections / complications
  • Gram-Negative Bacterial Infections / drug therapy
  • Gram-Negative Bacterial Infections / veterinary
  • Horse Diseases / diagnosis
  • Horse Diseases / drug therapy
  • Horse Diseases / microbiology
  • Horses
  • Lawsonia Bacteria
  • Protein-Losing Enteropathies / microbiology
  • Protein-Losing Enteropathies / veterinary
  • Rifampin / therapeutic use
  • Weaning


This article includes 7 references
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This article has been cited 4 times.
  1. Pusterla N, Gebhart C. Equine proliferative enteropathy caused by Lawsonia intracellularis.. Equine Vet Educ 2009 Aug;21(8):415-419.
    doi: 10.2746/095777309X453119pubmed: 32313386google scholar: lookup
  2. Pusterla N, Gebhart C. Lawsonia intracellularis infection and proliferative enteropathy in foals.. Vet Microbiol 2013 Nov 29;167(1-2):34-41.
    doi: 10.1016/j.vetmic.2013.06.017pubmed: 23871678google scholar: lookup
  3. Pusterla N, Gebhart CJ. Equine proliferative enteropathy--a review of recent developments.. Equine Vet J 2013 Jul;45(4):403-9.
    doi: 10.1111/evj.12075pubmed: 23662705google scholar: lookup
  4. Dauvillier J, Picandet V, Harel J, Gottschalk M, Desrosiers R, Jean D, Lavoie JP. Diagnostic and epidemiological features of Lawsonia intracellularis enteropathy in 2 foals.. Can Vet J 2006 Jul;47(7):689-91.
    pubmed: 16898113