Eosinophilic Keratitis in Cats: A 2025 Vet Guide to Symptoms, Causes & Treatment 🐱👁️

By Dr. Duncan Houston, BVSc

Eosinophilic keratitis is a chronic inflammatory eye condition in cats characterized by the infiltration of eosinophils—a type of white blood cell—into the cornea. This comprehensive 2025 veterinary guide delves into the causes, symptoms, diagnosis, treatment, and prevention of eosinophilic keratitis in felines.

Understanding Eosinophilic Keratitis 🧬

Eosinophilic keratitis involves the accumulation of eosinophils within the corneal tissue, leading to inflammation and the formation of characteristic lesions. These lesions often appear as raised, white to pink, chalky plaques on the cornea and may affect one or both eyes. The condition is considered immune-mediated, and while the exact cause remains unknown, a strong association with feline herpesvirus-1 (FHV-1) has been observed in up to 75% of cases. :contentReference[oaicite:8]{index=8}

Common Symptoms 🔍

Signs of eosinophilic keratitis in cats can vary but often include:

• Raised, white to pink lesions on the cornea
• Redness and inflammation of the eye
• Squinting or excessive blinking
• Watery or mucoid eye discharge
• Pawing at the eyes due to discomfort
• Visible blood vessels across the cornea
• Sensitivity to light (photophobia)

These symptoms necessitate veterinary evaluation to confirm the diagnosis and initiate treatment.

Potential Causes 🐾

Several factors can contribute to the development of eosinophilic keratitis in cats:

• Feline herpesvirus-1 (FHV-1): A common viral infection in cats that has been linked to the onset of eosinophilic keratitis. :contentReference[oaicite:9]{index=9}
• Immune-mediated response: An abnormal immune reaction leading to eosinophil infiltration in the cornea.
• Allergic reactions: Hypersensitivity to environmental allergens may play a role in some cases.

Identifying the underlying cause is essential for effective treatment and management.

Diagnosis 🩺

Diagnosing eosinophilic keratitis involves a combination of clinical evaluation and diagnostic tests:

• Physical examination: Observing the characteristic corneal lesions and assessing the extent of inflammation.
• Corneal cytology: Collecting a sample from the corneal surface to identify eosinophils and other inflammatory cells under a microscope. :contentReference[oaicite:10]{index=10}
• Fluorescein staining: Detecting corneal ulcers or abrasions that may be present alongside eosinophilic keratitis.
• Schirmer tear test: Measuring tear production to rule out dry eye conditions.
• Tonometry: Measuring intraocular pressure to exclude glaucoma. :contentReference[oaicite:11]{index=11}

Accurate diagnosis is crucial for determining the appropriate treatment plan.

Treatment Options 💊

Treatment strategies focus on reducing inflammation, managing symptoms, and addressing any underlying causes:

• Topical corticosteroids: Medications like dexamethasone to reduce corneal inflammation. :contentReference[oaicite:12]{index=12}
• Topical immunosuppressants: Agents such as cyclosporine or tacrolimus to modulate the immune response. :contentReference[oaicite:13]{index=13}
• Antiviral medications: Oral famciclovir or topical cidofovir to manage concurrent FHV-1 infection. :contentReference[oaicite:14]{index=14}
• Antibiotics: Topical antibiotics like Terramycin to treat or prevent secondary bacterial infections. :contentReference[oaicite:15]{index=15}

It's important to note that corticosteroids should be used cautiously, especially if corneal ulcers are present, as they can delay healing. In such cases, ulcers must be treated and healed before initiating steroid therapy.

Prognosis 📈

The outlook for cats with eosinophilic keratitis varies depending on the severity of the condition and the response to treatment. While many cats respond well to therapy, the condition is often chronic and may require long-term or lifelong management. Regular veterinary follow-ups are essential to monitor progress and adjust treatment as needed. :contentReference[oaicite:16]{index=16}

Preventive Measures 🛡️

Preventing eosinophilic keratitis involves proactive health management:

• Regular veterinary check-ups: Early detection of eye issues can lead to prompt treatment.
• Managing FHV-1: For cats with known herpesvirus infections, minimizing stress and potential triggers can help reduce flare-ups.
• Environmental control: Reducing exposure to potential allergens may help prevent immune-mediated responses.

Implementing these measures can significantly reduce the risk of eosinophilic keratitis.

When to Consult a Veterinarian 👩‍⚕️

Seek veterinary attention if your cat exhibits any of the following signs:

• Persistent eye redness or discharge
• Visible lesions or plaques on the cornea
• Squinting or pawing at the eyes
• Increased sensitivity to light

Early diagnosis and treatment are key to a successful outcome.

Conclusion 📝

Eosinophilic keratitis is a manageable condition in cats that requires prompt diagnosis and appropriate management. Understanding the causes, recognizing the symptoms, and implementing preventive measures are essential steps in ensuring your cat's eye health and overall well-being.

For personalized advice and support, consider reaching out to veterinary professionals through platforms like Ask A Vet. Their expertise can guide you through diagnosis, treatment options, and ongoing care tailored to your cat's specific needs.

Stay proactive in your cat's health to ensure a happy and healthy life together. 🐾