Download GENUS HELICOBACTER IN THOROUGHBREDS

GENUS HELICOBACTER IN THOROUGHBREDS HISTOPATHOLOGY AND
IMMUNOHISTOCHEMISTRY
Abelardo A. Morales, Victor M. Bermúdez and Francisco García
Introduction: Genus Helicobacter had been reported in gastric mucosa of horses by PCR
and histopathology. Recently, a new entero-hepatic Helicobacter species, H. equorum, was
isolated from faecal samples of two clinically healthy horses. The presence of gastric
Helicobacter-like organisms (HLO) in the stomachs of equines has been known for many
years but the relationship of those organisms to gastric disease remains controversial.
Objective: The aim of this study was to detect the presence of Helicobacter infection in
Thoroughbred horses in Venezuela. Material and Methods: Samples of gastric mucosa
were collected from 64 Thoroughbred horses at the National Racetrack “La Rinconada”,
Caracas, Venezuela. All cases were examined by histopathology and special stain (Giemsa,
Toluidin Blue and Warthin-Starry) and immuno-histochemical staining specific for
Helicobacter pylori. Results: All horses presented Gastric Equine Ulcer Syndrome and
gastric lesions grade 3. Histopathology revealed extensive chronic erosive gastritis and
multifocal ulcers. The lesions observed included a loss of continuity of the gastric mucosa
with lamina propria exposure and subchorionic edema, in addition to severe lymphoplasmocytic infiltration. Spiral-shaped bacteria on the surface and intragastric were found in
27/64 cases. Special Giemsa stain revealed 20/64, Toluidin Blue 26/64 and Warting Starry
27/64. Immuno-histochemical staining specific for Helicobacter pylori was negative in all
cases. Immuno-histochemical results suggest that H. pylori is not present, but rather other
bacteria of the genus Helicobacter. Conclusion: Our results suggest a prevalence of 42%
of the genus Helicobacter in equine gastric ulcer syndrome. These results support evidence
that Helicobacter species might be an important cause of equine gastric ulcer syndrome in
Thoroughbreds in Venezuela.
Department of Veterinary Pathology, Faculty of Veterinary Science,
Central University of Venezuela, Aragua State - Venezuela.