Conjunctivitis

Conjunctivitis, commonly known as pink eye, is an infection of the conjunctiva (the outer-most layer of the eye that covers the sclera). The three most common types of conjunctivitis are: viral, allergic, and bacterial. Each requires different treatments. With the exception of the allergic type, conjunctivitis is typically contagious.

The viral type is often associated with an upper respiratory tract infection, cold, or sore throat. The allergic type occurs more frequently among those with allergic conditions. When related to allergies, the symptoms are often seasonal. Allergic conjunctivitis may also be caused by intolerance to substances such as cosmetics, perfume, or drugs. Bacterial conjunctivitis is often caused by bacteria such as staphylococcus and streptococcus. The severity of the infection depends on the type of bacteria involved.

Signs and Symptoms

Viral conjunctivitis

· Watery discharge

· Irritation

· Red eye

· Infection usually begins with one eye, but may spread easily to the fellow eye

Allergic conjunctivitis

· Usually affects both eyes

· Itching

· Tearing

· Swollen eyelids

Bacterial conjunctivitis

· Stringy discharge that may cause the lids to stick together, especially after sleeping

· Swelling of the conjunctiva

· Redness

· Tearing

· Irritation and/or a gritty feeling

· Usually affects only one eye, but may spread easily to the fellow eye

Diagnosis

Conjunctivitis is diagnosed during a routine eye exam using a slit lamp microscope. In some cases, cultures are taken to determine the type of bacteria causing the infection.

Treatment

Conjunctivitis requires medical attention. The appropriate treatment depends on the cause of the problem.

For the allergic type, cool compresses and artificial tears sometimes relieve discomfort in mild cases. In more severe cases, non-steroidal anti-inflammatory medications and antihistamines may be prescribed. Some patients with persistent allergic conjunctivitis may also require topical steroid drops.

Bacterial conjunctivitis is usually treated with antibiotic eye drops or ointments that cover a broad range of bacteria.

Like the common cold, there is no cure for viral conjunctivitis; however, the symptoms can be relieved with cool compresses and artificial tears (found in most pharmacies). For the worst cases, topical steroid drops may be prescribed to reduce the discomfort from inflammation. Viral conjunctivitis usually resolves within 3 weeks.

To avoid spreading infection, take these simple steps:

· Disinfect surfaces such as doorknobs and counters with diluted bleach solution

· Don’t swim (some bacteria can be spread in the water)

· Avoid touching the face

· Wash hands frequently

· Don’t share towels or washcloths

· Do not reuse handkerchiefs (using a tissue is best)

· Avoid shaking hands

Eye Conjunctival Infection

Bacterial Conjunctivitis

Bacterial conjunctivitis typically presents with a red eye(s), purulent (pus) discharge, a gritty sensation, and occasionally sticking shut of the eyelids in the morning. Vision is not affected. Most conditions in the adult are secondary to staphylococcus (staph) or streptococcus (strep) infections. If the discharge is severe, gonococcal (gonorrhea) conjunctivitis must be considered. In children, the bacteria known as Hemophilus influenza may be causative. This bacterial infection is not related to the common flu, which is viral in nature. Newborn infants with conjunctivitis must be evaluated for gonococcal and chlamydia conjunctivitis (sexually transmitted diseases), however, staphylococcus, streptococcus, and other infectious agents must be considered as well.

In most cases of adult or childhood conjunctivitis, treatment with topical antibiotics is initiated without cultures. If the ophthalmologist elects for cultures, antibiotic therapy is usually initiated and treatment changed later, as necessary, depending on culture results. Gonococcal conjunctivitis requires intravenous or intramuscular antibiotics in addition to topical therapy.

Viral Conjunctivitis

Viral conjunctivitis is usually secondary to the adenovirus. In many cases, onset follows an upper respiratory infection such as the common cold. A history of close contact with a family member or any other individual with a "red eye" is also commonly elicited. The affected patient usually presents with redness of one or both eyes, watery or scant mucus discharge, and generally good vision.

The ophthalmologist may find conjunctival signs of viral infection known as follicles and an enlarged pre-auricular node (located in front of the ear). In some cases, the cornea of the affected eye will develop immune-related opacities known as subepithelial infiltrates. These may affect vision and can take several months to resolve. Most cases of viral conjunctivitis will run their course in about three weeks.

Treatment is usually limited to symptomatic therapy, much as one would treat the common cold. Vasoconstrictor and antihistamine combinations in eye-drop form may be very helpful in relieving symptoms. In cases in which subepithelial infiltrates develop and affect vision, steroids may sometimes be recommended to control symptoms and speed recovery. However, it is quite possible that once the steroids are discontinued, the disease may continue to run its course. Furthermore, long-term steroid use may be associated with development of cataracts or glaucoma.

Allergic Conjunctivitis

Allergic Conjunctivitis nearly always presents with a primary complaint of itching. A stringy but scant mucus discharge, red eyes, and other allergic symptoms such as rhinitis (stuffy, runny nose), "scratchy" throat, and dry, hacking cough are commonly present. Vision is rarely affected. The diagnosis is confirmed by the lack of infectious signs on slit-lamp (microscopic) examination in the office.

Treatment is aimed at symptomatic control, which in many cases may be chronic. Depending on the degree of symptoms, many patients can be controlled with over-the-counter vasoconstrictor and antihistamine eye-drop combinations. If this is ineffective, or the symptoms are more severe, a mild steroid eye-drop medication may be utilized temporarily, with eventual substitution of a mast-cell stabilizer eye-drop medication. Mast cells are the cells responsible for release of histamine and other mediators of inflammation and, ultimately, are responsible for itching. Patients, whose symptoms can only be controlled with steroids, and require the medication chronically, must be monitored for potential increases in eye pressure and cataract development.