Hypopyon in Dogs

Overview of Canine Hypopyon

Hypopyon is the accumulation of white blood cells within the liquid of the anterior (front) chamber of the dog’s eye. The cells are released from inflamed blood vessels located within the iris and the tissues behind the iris (ciliary body).

When inflammation of the dog’s iris and ciliary body occurs, also called anterior uveitis, these blood vessels leak cells and protein into the anterior chamber. In small quantities, the accumulation of cells in the anterior chamber fluid results in a cloudy or hazy appearance to the eye. When inflammation of the iris is severe, larger quantities of white blood cells are released from blood vessels and gravity causes them to accumulate on the bottom of the chamber or fill it entirely. Hypopyon usually appears white-to-yellow in color. Some clumps of cells may stick to the back of the cornea, producing tiny specks on the cornea.

In addition to cells, certain proteins are released from inflamed blood vessels that transform into strands called fibrin within the anterior chamber. Fibrin is commonly observed with hypopyon in eyes with severe anterior uveitis.

Hypopyon can develop in any eye with severe uveitis. For that reason, hypopyon represents a symptom of serious ophthalmic disease. Hypopyon is often caused by bacterial infections of the eye, or from systemic viral, fungal, bacterial, parasitic and protozoal infections that manifest within the eyes. Therefore, diagnostic tests are often essential in determining the underlying cause of this symptom.

Severe corneal ulceration also results in hypopyon.

What to Watch For

Diagnosis of Hypopyon in Dogs

Diagnostic tests for hypopyon may include:

Your veterinarian may recommend other diagnostic tests on a case-by-case basis. Tests may include:

Treatment of Hypopyon in Dogs

Preliminary treatment for hypopyon is usually initiated while the results of specific diagnostic tests are pending. These include:

Home Care for Dogs with Hypopyon

Do not delay in bringing the dogs to a veterinarian for examination as most causes of hypopyon are potentially vision threatening and require immediate medical attention.