Conjunctivitis

Overview, Causes, & Risk Factors

The conjunctiva is the clear mucous membrane layer covering the white portion of the eye. It extends under the eyelid where it turns back and becomes the underneath mucous membrane lining of the upper and lower lids. When this membrane becomes inflamed, it is called conjunctivitis.

What are the causes and risks of the infection?

Conjunctivitis can be caused by a number of factors, including:

allergies

bacterial, viral, and fungal infections

chemicals or fumes

foreign matter that gets under the eyelid

Symptoms & Signs

What are the signs and symptoms of the infection?

Symptoms of conjunctivitis can include:

discharge from the eyes

increased tearing

painful, itchy eyes

red, puffy eyes

sensitivity to light

Symptoms vary, depending on the cause. For instance, a colored discharge from the eye usually indicates a bacterial infection. But, when itching and tearing are the main symptoms, allergies are the most likely cause. With viral conjunctivitis, there is usually no discharge, but there may be redness and tearing.

Diagnosis & Tests

How is the infection diagnosed?

Diagnosis of conjunctivitis begins with a medical history and physical exam. The healthcare provider may use a slit-lamp microscope to examine the eye. This instrument magnifies the surface of the eye.

Prevention & Expectations

What can be done to prevent the infection?

Conjunctivitis cannot always be prevented. Some helpful measures include:

avoiding makeup, towels, linens, and other objects from an infected individual

practicing good lid hygiene, by rubbing the eyelids without soap under the water stream when showering

using good handwashing when coming into contact with a child or adult who has conjunctivitis

using safety glasses during work or hobbies in which debris is flying around in the air

What are the long-term effects of the infection?

If the cornea becomes infected or inflammation spreads to the eyelids, more serious problems such as cellulitis could occur. Cellulitis is an infection that can lead to abscesses, or pus pockets, and tissue destruction.

What are the risks to others?

Some forms of conjunctivitis are contagious from person to person.

Treatment & Monitoring

What are the treatments for the infection?

Treatment includes:

antibiotic eye drops or ointments for conjunctivitis caused by a bacterial infection

eye drops containing antihistamines, nonsteroidal anti-inflammatory agents, or corticosteroids if allergies are the cause

oral antibiotics if topical antibiotics alone do not solve the problem

removal of foreign matter from under the lids if this has caused the inflammation

What are the side effects of the treatments?

Eye drops may cause irritation or an allergic reaction. Antibiotics may cause stomach upset, rash, or allergic reaction.

What happens after treatment for the condition?

Most of the time, conjunctivitis clears up without any further problems.

How is the condition monitored?

Any new or worsening symptoms should be reported to the healthcare provider.

Article type: xmedgeneral