Eosinophilic colitis and hepatitis in a horse with colonic intramucosal ciliated protozoa.

This research paper discusses a case of eosinophilic colitis and hepatitis in a nine-year-old horse, associated with an overpopulation of ciliated protozoa in its colonic mucosa.

Introduction to the Case

• The research revolves around a case involving a 9-year-old American Standardbred gelding showing symptoms of anorexia, mild colic, and unexpected death.
• The post-mortem examination of the horse was handled by the Laboratories of Veterinary Diagnostic Medicine at the University of Illinois.

Microscopic Diagnoses

• Microscopic examinations revealed two critical diagnoses: severe subacute, diffuse eosinophilic colitis with intralesional protozoa, and a subacute to chronic eosinophilic portal hepatitis with granuloma formation.
• Eosinophilic colitis refers to inflammation of the colon caused by an increased number of eosinophils, a type of white blood cells, in the colon’s tissue and/or the periphery.
• Similarly, eosinophilic portal hepatitis is an inflammation of the liver, marked by the presence of eosinophils in portal areas.

Identified Protozoa

• The examination discovered the presence of two kinds of tissue-invading ciliated protozoa in large numbers within the colonic mucosa of the horse: Polymorphella ampulla and Cycloposthium sp., belonging to the Phylum: Ciliophora.
• Protozoa are single-celled organisms and these particular species are bioindicators and can give insight into the broader health conditions of the horse.

Interpretation

• The detection of eosinophilic colitis and portal hepatitis in the horse may have been as a result of an overpopulation and invasion by the identified ciliated protozoa.
• This suggests that these protozoa could be causal factors of the observed colitis and hepatitis, indicating the need for further research on the relationships between these diseases and the protozoa.