Bone abscess in the mandible of a quarter horse gelding.

The article reports on a case study where a Quarter horse gelding was successfully treated for a bone abscess found in its mandible due to a bacterial infection from Staphylococcus intermedius, without association to any tooth.

Case Presentation

• The subject of the study was a 4-year-old Quarter horse gelding with a noticeable swelling in the soft tissues over the intersection of the body and ramus (the vertical extension) of the left mandible (lower jaw).
• Upon radiographic examination, a well-defined lytic (referring to bone loss) region was discovered within the mandible which was unusually surrounded by signs of sclerosis (a condition characterized by hardening of the tissues) unlinked to any tooth.

Intervention and Outcome

• When the lesion was aspirated, or withdrawn by suction, pus was found, confirming the presence of an abscess.
• Following this, the abscess cavity was opened, curetted (a procedure where the abscess is scraped or cleaned), and lavaged (washed out with a large volume of fluid).
• A Penrose drain, a device used to remove excess fluids, was put in the abscess cavity and left for 10 days to ensure the complete drainage of pus and other lengths.
• The bacteriological culture of the drained fluid and the abscess’s soft tissues yielded a few colonies of Staphylococcus intermedius, highlighting this bacterium’s role in the chronic infection. This species is commonly associated with superficial skin diseases in dogs but rarely found in equine species.
• The histopathology or microscopic examination of the affected tissues confirmed a chronic pyogenic infection, which is a long-lasting infection that leads to the formation of pus.
• The treatment proved successful, and the horse recovered well, showing no signs of the abscess one year post-treatment.