Infectious ulcerative keratitis in horses, dogs, cats, and rabbits under Swedish conditions

Background

Increasing antimicrobial resistance is one of the greatest threats to both human and animal health. This trend can be inhibited through more prudent and responsible use of antibiotics. Corneal ulcers are common in animals, for example following trauma or as a complication of chronic eye disease. These injuries can cause severe pain and, in the worst cases, lead to impaired vision or even loss of the eye if treatment is not initiated promptly.

To reduce the risk of infection, antibiotics are often administered immediately after an eye injury is diagnosed. This is important because bacterial infections can progress rapidly and lead to severe complications, including vision loss or loss of the eye. Since treatment cannot be delayed while awaiting laboratory confirmation, the initial choice of antibiotic is based on clinical experience and existing knowledge of the microorganisms involved and their expected susceptibility patterns. Today, this knowledge is primarily based on international studies of the microorganisms responsible for eye infections and their antibiotic susceptibility patterns. However, equivalent data from Sweden are lacking, making it difficult to tailor empirical treatment recommendations to Swedish conditions.

This project aims to

• Identify the fungi and bacteria involved in corneal infections (infectious ulcerative keratitis) in Swedish horses, dogs, cats, and rabbits, and to evaluate the resistance profiles of these microorganisms.

• Evaluate the agreement between cytological examination and conventional culture of samples from corneal ulcers.

• Identify factors that may influence healing time, treatment duration, and prognosis in infectious ulcerative keratitis.

• Establish a scientific basis for future work on national guidelines for the treatment of infectious ulcerative keratitis.

Implementation of the project

Samples from the eye will be collected from Swedish horses, dogs, cats, and rabbits with corneal ulcers and analysed for the presence of aerobic and anaerobic bacteria and fungi, as well as their antimicrobial susceptibility and resistance profiles. The microbiological culture results will be compared with findings from corneal cytology, which is routinely used in clinical practice to provide a rapid initial assessment of infection.

We will also study healing time and the occurrence of complications in dogs with indolent corneal ulcers treated with topical antibiotics and compare these outcomes with those in dogs treated with lubricating eye drops alone.

Objectives

The overall aim of this project is to improve knowledge of the microorganisms that cause eye infections in animals and their susceptibility to antibiotics. This knowledge will support the selection of appropriate treatment from the outset, promoting faster healing, reducing animal suffering, and increasing the likelihood of preserving vision. In the longer term, more targeted use of antibiotics use may help inhibit the development of antimicrobial resistance. The findings will also provide an important scientific basis for future updates of Swedish guidelines on antimicrobial use in veterinary ophthalmology, contributing to more effective and sustainable animal healthcare.

Collaborations

In addition to the participants from SLU, the project group also includes the following:

• Oskar Nilsson, Swedish Veterinary Agency (SVA)
• Sara Littorin, AniCura, Bagarmossen