Excess Blood Cells in the Eye in Cats

Anterior uveitis is an inflammation of the uveal tract, which includes the iris, ciliary body, choroid, and sometimes the retina. It is often associated with a systemic disease or severe trauma and can clinically present itself like conjunctivitis. Anti-inflammatory medication and modern laboratory techniques are making control of the condition more efficient. However, the disease is not always controllable and will usually require lifetime treatment.

Excess blood cells located within the eye is due to inflammation that results in a leak across the blood-aqueous barrier into an anterior chamber (the lower front portion) of the eye. The blood cells accumulate, creating a condition called hypopyon, which is an uncommon indicator of a broader ocular disease called uveitis. The condition can occur in one eye or both eyes. Uveitis can affect vision or be destructive to the eye by leading to cataract, glaucoma, and blindness. If an underlying, undetected condition is the cause, removal of the eye or even death may also be possible. Immediate attention and treatment is necessary. 

Symptoms of uveitis and resulting hypopyon may include:

• White to yellow or milky opacity within the anterior chamber
• Twitching
• Corneal swelling
• Constriction of the pupil, causing an irregular appearance
• Swelling of the iris
• Vision loss
• Excessive tearing
• Congested or red conjunctiva
• Protruding inner eyelid
• Pus or the appearance of a cyst
• Abnormally red or bloodshot eyes
• Pain
• Lesions or cysts

Anterior uveitis is usually caused by systemic infectious disease, trauma, or cancer. The most common infections are:

• Feline immunodeficiency virus (FIV)
• Feline herpesvirus-1 (FeHV-1)
• Toxoplasmosis (a parasite that can be found in undercooked meat)
• Feline leukemia virus (FeLV)
• Feline infectious peritonitis (abdominal infection)
• General fungal or bacterial infection
• Hypertension
• Cancer, most commonly lymphoma or iris melanoma. 

If the cat is sick at the time of recognition of an eye problem, it is the cause of the sickness that is most likely the cause of the uveitis.

At home, if you observe your cat’s eye has become red or swollen, or if you notice the appearance of a growth with or without a pus-like or watery discharge, call your veterinarian as soon as you can. The earlier the treatment, the more success there will be in saving your cat’s eyesight. 

Your veterinarian will initially want to conduct an overall physical examination, take a medical history, and perform an eye exam to detect any possible injuries to the eye. 

The diagnosis process will also include a full blood count, heartworm test, a test on the fluid coming from the eye, and any testing to determine FeLV, FIV, or any kind of infection.

If the cause of the inflammation cannot be determined, you will be referred to a veterinary ophthalmologist.

Treatment will most likely be directed at the underlying disease that is causing the uveitis. If cancer is the cause, then depending on how widespread the cancer is, the eye may be removed. In rare cases, surgery may be necessary to remove any localized infection.

The presence of glaucoma (intraocular pressure) will be carefully watched and aggressively controlled if found. If left untreated, the eye will become painful and blindness will develop, resulting in having to remove the eye. No outward symptoms of pain will be apparent other than the suspicion that your cat has a headache. If glaucoma is found but your veterinarian does not have the correct instrument to measure intraocular pressure, you will be referred to a veterinary ophthalmologist. 

Medications that will be administered are: 

• Topical corticosteroid to treat cloudiness, reduce the inflammation, and reduce the chance of developing glaucoma
• Topical or systemic non-steroidal anti-inflammatories 
• Topical or oral antibiotics
• Atropine to dilate the pupil to help monitor for the development of secondary glaucoma
• Antifungals or antiparasiticides if necessary
• Immunosuppression drugs if necessary

Recovery from acute anterior uveitis is usually very good with proper and early treatment. However, if the condition is recurrent or chronic the outlook is less favorable. This is because of the high probability of developing secondary cataracts, glaucoma, and phthisis bulbus (shrunken eye).

If the anterior uveitis is not controlled with the use of anti-inflammatories, if the cause cannot be determined, or if glaucoma is detected, your veterinarian may refer you to a board-certified ophthalmologist. 

It should be noted that uveitis is a disease that your cat will have the rest of its life, and so it will always require treatment and care. If symptoms pertaining to anterior uveitis should reappear in between regular check-ups, call your veterinarian immediately.