Cat Conjunctivitis (Feline Pink Eye)

Signs and Symptoms

Cat conjunctivitis affects many felines, often chronically. It can come and go throughout a cat’s life, causing great discomfort. If left untreated, the more severe cases of this disease can even cause blindness. As a pet owner, it’s always a good idea to be familiar with the symptoms of conjunctivitis so that you can recognize the warning signs early on and have your cat examined and treated by a veterinarian. Early detection will prevent the condition from progressing, will lower the likelihood of other cats becoming infected, and will relieve your pet’s suffering and discomfort.

One of the common symptoms of conjunctivitis is redness of the affected eye or eyes, which may be accompanied by swelling and tearing. This particularly occurs in the corner of the eye. Cats with conjunctivitis also tend to squint, keeping their eyes half closed. The third eyelid may also be more noticeable, possibly protruding out so that it covers the eyeball. Since this condition can cause the eyes to be painful and uncomfortable, an infected cat may rub at its eyes. In some cases of feline conjunctivitis, a pus-like discharge may be present that can be clear, yellow, grey, green, or dark red. Under some circumstances, the iris of the eye may change color, becoming duller than normal. In addition, many cats suffering from conjunctivitis tend to avoid light and brightly lit areas. Finally, some cats with this condition may also exhibit symptoms of an upper respiratory infection, such as sneezing.

Cats with conjunctivitis may display only some of these signs and symptoms, or all of them together. Furthermore, one eye or both eyes can be affected. This is a very unpleasant condition for your cat to suffer through; so if you notice your pet displaying one or more of the above symptoms, be sure to alert your veterinarian immediately.

Diagnosis

A veterinarian can make a simple diagnosis of feline conjunctivitis quite easily. Often, this only requires going over the cat’s history, looking for clinical signs of the condition, and ruling out other possible causes of eye irritation. These other causes could include the presence of a foreign object in the eye, blockage of the tear ducts, or damage to the cornea. However, sometimes a more specific diagnosis is required, especially if the underlying cause of the condition needs to be identified in order to ensure effective treatment. In such cases, diagnostic methods that may be employed include blood tests, cell cultures, cytology, and DNA tests.

When conjunctivitis is suspected to be the source of a feline patient’s suffering, blood tests can be used in order to look for signs of infection that could be causing the condition. In the case of a cell culture or cytology, a sample is taken from either the conjunctiva or the cornea. Often, such a sample is obtained by way of a swab. It is then sent to a laboratory for culture or, in the case of cytology, it is inspected under a microscope. These tests are also used to search for possible underlying infections. Finally, in some circumstances, a special DNA test may be necessary in order to check for a specific infectious organism known as Feline Herpesvirus-1. These special tests help a veterinarian to pinpoint the cause and origin of the feline conjunctivitis, which can be very helpful with regards to selecting an appropriate course of treatment.

Pathophysiology

In medical terminology, the suffix “itis” refers to inflammation. Therefore, conjunctivitis is basically inflammation of the conjunctiva. The conjunctiva is a thin mucus membrane that covers the eye’s sclera or outer layer. It also covers the cat’s inner eyelid. This layer consists of epithelial and mucus-succeeding cells. In healthy felines, the conjunctiva is pale pink in color and not very visible. However, when a cat develops conjunctivitis, this membrane becomes swollen and inflamed. It tends to turn red and bulge out from the eyelids, making it more visible. This condition can affect just one eye or both eyes, and thus can be classified as either unilateral or bilateral.

Causes

There are several different conditions and factors that can cause feline conjunctivitis. All these causes fall roughly into two different categories — non-infectious causes and infectious causes. Non-infectious causes of conjunctivitis include trauma to the eye that may occur during a cat fight or other event. Allergies or foreign objects such as sand can also give rise to this condition. Other irritants, such as chemicals, can also be non-infectious triggers of conjunctivitis. Furthermore, in some cases congenital defects give rise to this disease. For example, some breeds like Persians are born with a turned in eyelid. This causes the eyelashes to continuously rub against the eyeball, causing irritation and leading to conjunctivitis.

With respect to infectious triggers, there are three main causative agents. Feline chlamydia and feline mycoplasma are two of these causes. Chlamydia is a type of bacteria, many strains of which can affect cats, while mycoplasmas are organisms that are similar to bacteria. Both chlamydia and mycoplasma are able to trigger the development of conjunctivitis without the aid of any secondary infections. However, perhaps the most common infectious cause of feline conjunctivitis is a type of cat flu virus known as Feline Herpesvirus-1. This is an upper respiratory virus, also known as rhinotracheitis, and is not transferable to humans. Most cats are exposed to this virus as kittens and for many felines it will cause them no further problems. However, Feline Herpesvirus-1 can lie dormant in a cat’s body until the immune system becomes stressed, when it will then flare up. The fact that this virus often causes conjunctivitis is the reason why sneezing and other symptoms of a respiratory infection sometimes accompany the other common signs of feline conjunctivitis.

In most cases, when cat conjunctivitis is caused by a non-infectious factor, the onset will be quite sudden. On the other hand, when caused by infectious triggers, the onset may be slower and the condition may affect the animal in a more chronic fashion. Pinpointing the underlying condition or factor that has caused your cat’s conjunctivitis will help your veterinarian to select the most appropriate and effective treatment plan.

Treatment

The treatment and prognosis of this condition will vary depending on the underlying cause of the conjunctivitis. When this disease is triggered by Feline Herpesvirus-1 it cannot be completely cured, only controlled. However, proper treatment of this virus will reduce the severity and frequency of flare ups, greatly increasing your cat’s comfort and enjoyment of life. Sometimes future flare ups will not occur at all. When conjunctivitis is caused by other factors, proper treatment will often effectively cure the problem. Treatments are generally administered in three different ways. One method is to use drops or ointments that are locally administered into the eye. Another form of local administration is through the injection of medication under the conjunctiva. Finally, other treatment methods are non-local and can be administered through an injection or through oral ingestion of a pill or liquid.

The type of medication required will also depend upon the underlying cause. For example, conjunctivitis triggered by chlamydia will need to be treated with antibiotics. However, homeopathic remedies are known to be very effective in many cases of feline conjunctivitis, especially those remedies that contain antibiotic and antiseptic properties. Several natural substances have such properties, including eyebright, goldenseal, and rosemary. These ingredients also have anti-inflammatory properties, which reduce the swelling commonly caused by conjunctivitis. Furthermore, other natural herbs and substances such as chamomile have an analgesic effect, soothing pain and irritation. As a result, homeopathic remedies can be very beneficial with respect to relieving the troublesome symptoms caused by conjunctivitis as well as targeting and combating the actual cause of the disease.

Alleviating your pet’s suffering as quickly and effectively as possible is, of course, ideal. This is why it’s important that your cat be examined by a veterinarian as soon as you observe any unusual symptoms or behaviors. This will allow for prompt diagnosis, followed by an appropriate course of treatment that will restore your cat’s health and happiness.