Conjunctivitis in dogs & cats
What is conjunctivitis?
Conjunctivitis is an eye condition characterised by the inflammation of the conjunctiva membrane which covers the front of the eye and the eyelids. Though not lethal, pets suspected of conjunctivitis should see a vet as soon as possible as eyesight is one of their most important senses.
It can affect one or both of the eyes, and aside from causing the usual physical symptoms, pets suffering conjunctivitis can be extremely uncomfortable, as it can be irritating, itchy, and painful. It is important to take caution around affected pets as even the gentlest cat or dog can become snappy.
- Blephora: this refers to spasmodic blinking and/or squinting.
- Redness: affected pets will have a reddish, moist appearance around the eye.
- Discharge: clear or pus-like discharge can come from the eyes.
- Swelling: a build-up of moist tissue around the eyeball can cause swelling in the eye.
- Follicle formation: accumulations of lymphoid tissue located at the moist eyelid surface causes a cobblestone-like appearance .
Conjunctivitis is quite easy to identify since it produces visible signs around the eyes. A mucus-like discharge usually indicated a bacterial or fungal cause, and can be so thick it causes the eyelids to stick together. A clear, watery discharge usually results from an allergy or irritant. Pus, which can form a crust around the eye, indicates a bacterial cause, usually Streptococcus or Staphylococcus.
A visual exam is usually enough to make a diagnosis, though a mucus discharge may prompt a Schirmer Tear Test, which assesses if there is sufficient tear production. To rule out corneal damage or ulceration, a vet may also perform a Fluorescein Stain, in which a dye is applied to the eye and affected areas become green.
Treatment and management
Treatment of conjunctivitis depends on the cause – bacterial infections can be treated with antibiotics and fungal infections can be treated with antifungal ointments. If conjunctivitis has caused an obstruction in the eye, surgery may be required to clear it. Some cases may be caused by cancer, so surgical removal of the tumour may be the best course of action.
Since conjunctivitis can be caused by a number of factors, it is very difficult to prevent it. However, because it can be contagious, it is important to isolate an affected pet from other household animals. Keeping your pet’s eyes clean and free of potential irritants is the best way to lower its risk.
Though not life-threatening, advanced conjunctivitis can spread and affect other eye structures, possibly resulting in vision impairment.
Conjunctivitis may be a symptom of a serious and highly contagious disease, canine distemper.