Conjunctivitis

Definition

Conjuctivitis is an inflammation (redness) of the lining of the white part of the eye and the underside of the eyelid (conjunctiva). It can be caused by infection, allergic reaction, or physical agents like infrared or ultraviolet light.

Description

Conjunctivitis is a common eye problem because the conjunctivae are continually exposed to microorganisms and environmental agents that can cause infections or allergic reactions. Conjunctivitis can be acute or chronic depending upon how long the condition lasts, the severity of symptoms, and the type of organism or agent involved. It can affect one or both eyes. If it is caused by infection, it can be easily transmitted to others during close physical contact, particularly among children in a daycare center. Other names for conjunctivitis include pinkeye and redeye.

Causes & symptoms

Conjunctivitis may be caused by a viral infection, such as a cold, acute respiratory infection, or disease such as measles, herpes simplex, or herpes zoster. Symptoms may include mild to severe discomfort in one or both eyes; redness; swelling of the eyelids; and a watery, yellow, or greenish discharge. The symptoms may last anywhere from several days to weeks. Infection with an adenovirus, however, may also cause a significant amount of pus-like discharge and a scratchy sensation in the eye. These symptoms may also be accompanied by swelling and tenderness of the lymph nodes near the ear.

Bacterial conjunctivitis may occur in adults or children. It is caused by such organisms as Staphylococcus, Streptococcus pneumoniae, and Haemophilus. Symptoms of bacterial conjunctivitis include a pus-like discharge and crusty eyelids after awakening. Redness of the conjunctivae can be mild to severe and may be accompanied by swelling. Persons with symptoms of conjunctivitis who are sexually active may possibly be infected with chlamydia or with the bacteria that cause gonorrhea. There may be large amounts of pus-like discharge. Symptoms may include hypersensitivity to light (photophobia), a watery mucous discharge, and tenderness in the lymph nodes near the ear that may persist for up to three months.

Conjunctivitis may also be caused by such environmental hazards as wind, smoke, dust, and allergic reactions caused by pollen, dust, or grass. Symptoms range from itching and redness to a mucous discharge. Persons who wear contact lenses may develop allergic conjunctivitis caused by the various eye solutions and foreign proteins contained in them.

Other less common causes of conjunctivitis include looking at the sun, sun lamps, plant lamps, or the electrical arcs used during welding, as well as defective tear ducts.

Diagnosis

Accurate diagnosis of conjunctivitis centers on taking the patient's history to learn when symptoms began, how long the condition has been going on, the symptoms experienced, and other predisposing factors. Diagnostic tests may include an eye examination, culture, or laboratory test. The discharge may be cultured and Gramstained to determine the organism responsible for causing the condition. Cultures and smears are relatively painless.

Treatment

Conjunctivitis caused by gonococcal or chlamydial infection usually requires prescription antibiotics. Internal immune enhancement with dietary supplements can aid in the resolution of allergic and viral conjunctivitis. Removal of the allergic agent is an essential step in treating allergic conjunctivitis. As with any of the recommended treatments, however, if no improvement is seen within 48–72 hours, a physician should be consulted.

Nutritional therapy

The following dietary changes may be helpful in managing conjunctivitis:

• Taking 25,000 IU (international units) of beta-carotene twice daily for 7 days.
• Taking 500–1000 mg of vitamin C three times daily for 7 days.
• Taking 25 mg of zinc with meals three times daily for 7 days.

Homeopathy

There are a number of homeopathic remedies designed to treat acute conjunctivitis. These include Argentum nitricum (silver nitrate), pulsatilla (windflower), belladonna, Arsenicum album (arsenic trioxide), sulphur (elemental sulphur) and eyebright (Euphrasia officinalis). Eye drops prepared with homeopathic remedies can be a good substitute for pharmaceutical eye drops.

Herbal therapy

Herbal eyewashes made with eyebright (1 tsp dried herb steeped in 1 cup of boiling water for 10 minutes, then strained and used at once) or chamomile (Matricaria recutita; 2–3 tsp in 1 pint of boiling water) may be helpful. Eyewashes should be strained and cooled before use. They should be discarded promptly after use, as old infusions may become unsterile.

Other simple home remedies may help relieve the discomfort associated with conjunctivitis. A boric acid eyewash (1 tsp boric acid in 1 cup of water) can be used to clean and soothe the eyes. A warm compress applied to the eyes for 5–10 minutes three times a day can help relieve the discomfort of bacterial and viral conjunctivitis. A clean washcloth soaked in warm water can be used as a warm compress. The patient should close both eyes and apply the compress to the affected eye. A cool compress or cool, damp tea bags (of black tea or chamomile tea) placed on the eyes can ease the discomfort of conjunctivitis.

Allopathic treatment

The treatment of conjunctivitis depends on what caused the condition. In all cases, warm compresses applied to the affected eye several times a day may help to reduce discomfort.

Conjunctivitis due to a viral infection, particularly those due to adenoviruses, are usually treated by applying warm compresses to the eye(s) and applying topical antimicrobial ointments to prevent secondary bacterial infections.

Viral conjunctivitis may cause blindness and should be referred to an ophthalmologist. Topical steroids are commonly prescribed in combination with antiviral therapy.

In cases of bacterial conjunctivitis, a physician may prescribe an antibiotic eye ointment or eye drops containing sodium sulfacetamide (Sulamyd) to be applied daily for 7–14 days. Patients should contact their doctors if the eyes fail to improve after 72 hours. Antibiotic eye drops are instilled (put in drop by drop) into the eye by having the patient tilt the head back and pulling down the lower eye lid. The patient is asked to look upward while the medication is instilled into the conjunctival sac. It is important to avoid touching the dropper to the skin, in order to prevent the eye discharge from contaminating the antibiotic solution. After the drops have been instilled, the patient should gently close the eyes for 1 minute in order not to squeeze out any of the medication.

For cases of conjunctivitis caused by a gonococcus (the bacteria that causes gonorrhea), a physician may prescribe an injection of ceftriaxone (Rocephin) and a topical antibiotic ointment containing erythromycin or bactracin to be applied four times daily for 2–3 weeks. For chlamy-dial infections, a topical antibiotic ointment containing erythromycin (Ilotycin) may be prescribed to be applied 1–2 times daily. To apply an antibiotic ointment, the eye should be gently wiped with a sterile cotton ball moistened with sterile water to remove any discharge. Then, the lower eyelid can be pulled down and a thin ribbon of ointment applied in the lower conjunctival sac. If possible, single-dose dispensers of ointment should be used as a protection against contamination of the medication. The eyelids can be closed and massaged gently to distribute the ointment. Patients may find that their vision is blurry for a few minutes after the ointment is applied, but this is a normal side effect. In addition to topical antibiotics, oral erythromycin or tetracycline therapy may be indicated for 3–4 weeks. Sexual partners should also be treated.

Children with conjunctivitis should typically receive topical antibiotics, according to clinical evidence published in 2002. But the evidence re-emphasized that adults who have non-gonococcal conjunctivitis usually do not need antibiotic treatment, because antibiotic resistance is a growing problem.

Allergic conjunctivitis can be treated by removing the allergic substance from a person's environment, if possible; by applying cool compresses to the eye; and by administering eye drops 4–6 times daily for four days. Also, the antihistamine diphenhydramine hydrochloride (Benadryl) may help to relieve itchy eyes. In 2002, a new study showed that loteprednol and azelastine are two potential treatments for allergic conjunctivitis. Some doctors have prescribed ophthalimic steroids, but they can cause complications in patients. These potential new treatments offer alternatives to steroids for patients with allergic conjunctivitis.

Expected results

If conjunctivitis is treated properly, its prognosis is good. Conjunctivitis caused by an allergic reaction should clear up once the allergen is removed. Allergic conjunctivitis, however, will likely recur if the individual again comes into contact with the particular allergen. Conjunctivitis caused by bacteria or a virus, if treated properly, usually resolves in 10–14 days. If there is no relief of symptoms in 48–72 hours; or if there is moderate to severe eye pain or changes in vision; or if the conjunctivitis is suspected to be caused by herpes simplex, a physician should be notified immediately. If untreated or if treatment fails and is not corrected, conjunctivitis may cause visual impairment by spreading to such other parts of the eye as the cornea.

Prevention

Conjunctivitis can be prevented in many cases; in others, the course of the disease can be shortened by following some simple practices:

• Washing hands frequently using antiseptic soap; using single-use towels during the disease to prevent spreading the infection.
• Avoiding chemical irritants and known allergens.
• In areas where welding occurs, using the proper protective eye wear and screens to prevent damaging the eyes.
• Using a clean tissue to remove discharge from eyes, and washing hands to prevent the spread of infection.
• If medication is prescribed, finishing the course of antibiotics as directed to make sure that the infection is cleared up and does not recur.
• Avoiding wearing eye makeup or contact lenses during the infection. Never share eye makeup with others.

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