Pink Eye
What is Pink Eye?
Pink eye, otherwise called Conjunctivitis, is redness and inflammation of the conjuctiva membranes covering the whites of the eyes and the membranes on the inner part of the eyelids. These membranes react to a wide range of bacteria, viruses, allergy-causing substances, irritants and toxic agents; as well as to other diseases in the body. Viral and bacterial forms of conjunctivitis are more common in childhood, but they can occur in people of any age.
Symptoms of Pink Eye
The symptoms of pink eye vary as per the cause of infection and the severity of the condition:
Redness: In most types of conjunctivitis, whatever may be the cause, there is a marked redness or soreness of the eyes. This is the best sign to diagnose pink eye. Bacterial infection or toxic conjunctivitis shows more redness than viral although the discomfort in all types is extreme.
Discharge: A purulent discharge (a substance more commonly known as pus) strongly suggests infective conjunctivitis, unless there is known exposure to toxins. A greenish discharge shows bacterial infection and brownish discharge indicates viral infection. If the mucoid discharge is extremely thick and copious then the eyes may have been infected by the bacterium neisseria gonorrhoeae.
This discharge commonly accumulates after sleeping. Affected patients may awaken feeling that their eyelids are stuck shut and they cannot open their eyes without discomfort. First thing in the morning, a warm, clean, moist cloth has to be applied to the eyes to remove the discharge.
Itching and watering: A strong itching feeling in the eyes along with redness is a sign of allergic conjunctivitis. The eyes also keep watering all the time causing discomfort.
Blurring vision/Photophobia: Mild blurring of vision and mild photophobia is present due to mucoid discharge. If blurring and photophobia are very severe; or if they do not go after conjunctivitis treatment, then additional tests should be carried out to eliminate possibility of more serious eye problems like glaucoma, uveitis and keratitis.
Runny nose: Cold-like symptoms, similar to those of sinus congestion, are also present if it is viral conjunctivitis. The eyelids may be swollen. Sometimes looking at bright lights is painful.
Scarring: Evidence of scarring on bio-microscopy shows signs of corneal vascularisation as well.
Diagnosis of Pink Eye
There are various tangible signs with which the ailment of pink eye can be diagnosed. The most obvious one is redness of the eyes. Conjunctivitis is treated empirically and successfully, but often only after going through a whole series of possible causes. Some methods of diagnosis to find the cause of pink eye are:
Schirmer test: This test is carried out to check for dry eye or unstable tear film problems, which may be the cause of redness of the eyes.
Swabs: Swabs for bacterial culture are necessary to check for bacterial infection. This is carried out mostly to eliminate the possibility of bacterial infection of the eyes as sometimes the laboratory tests would be negative despite redness of the eyes.
Viral culture: This is more appropriate in epidemic cases and contagious conjunctivitis. Conjunctival scrapes for cytology can be useful in differentiating chlamydial, fungal infections and allergy-related conjunctivitis.
Biopsy: An incisional biopsy of the conunctiva is carried out only when granulomatous (infected ulceration) diseases or dysplasia are suspected as cause of redness of the eyes.
Causes of Pink Eye
Overall however, there are many causes of pink eye. These can be classified as either infectious or noninfectious.
A) Infectious type:
1) Viral infection: This infection must be correctly detected and treated. Viral pink eye is highly contagious and is caused by various viruses. Patients are often advised to avoid touching their eyes or sharing towels and washcloths.
2) Bacterial infection: This type of conjunctivitis is caused by bacteria like staphylococci, pneumococci or streptococci.
3) Chlamydia (bacteria): This is a form of bacterial pink eye which occurs only in the event of sexual activity. It is not exactly contagious.
B) Non-infectious type:
1) Toxicity: If the cause is splash of some toxic substance, the eyes are very painful when the infected eye is pointed far down or far up, but there is no itch. There is no discharge either. Household cleaners, sprays of any kind, smoke, smog and industrial pollutants could be the possible causes here.
2) Allergies: Seasonal pollen, dust and animal dander can also cause allergic conjunctivitis. Here the eyes would itch and water a lot causing discomfort.
Types of Pink Eye
A) Infectious conjunctivitis:
1) Pyogenic bacterial conjunctivitis: This is caused by pyogenic (pus-producing) bacteria. The conjunctiva shows an opaque purulent (a whitish-yellow or greenish substance more commonly known as pus) discharge and a very red eye. A Bio-microscopy would show numerous white cells and desquamated epithelial cells in the ‘tear gutter’ along the lid margin. Pyogenic infections are difficult to diagnose as they show just mild symptoms. The discharge accumulates while sleeping and this causes the “shut eye” feeling on waking up.
2) Inclusion conjunctivitis of the newborn (ICN): This is caused by the bacteria Chlamydia trachomatis, and may lead to acute and purulent conjunctivitis. However, it is usually self-healing.
3) Viral conjunctivitis: In this case of viral pink eye infection, along with a variable itch and redness of eyes there is a brownish discharge. Viral pink eye, if neglected, can lead to infection of the cornea (the clear portion of the front of the eyeball). Viral pink eye usually subsides in 7 to 10 days after symptoms appear. The infection usually begins with one eye, but may spread easily to the other.
B) Non-infectious conjunctivitis:
Allergic conjunctivitis: Here, the conjunctiva shows signs of pale watery swelling or edema. There is a non-purulent (not pus) mucous discharge but there is variable redness.
Irritant or toxic conjunctivitis: In this type of conjunctivitis, a marked redness is the primary sign. If it is due to toxic-liquid splash injury, it is often present only in the lower conjunctival sac. Some chemicals like caustic alkalis (e.g. sodium hydroxide) cause necrosis of the conjunctiva although showing a deceptively white eye due to vascular closure.
C) Persistent pink eye can be a sign of an underlying illness in the body like rheumatoid arthritis, systemic lupus erythematosus, ulcerative colitis, Crohn’s disease and Kawasaki’s disease (a rare disease associated with fever in infants and young children).
Treatment of Pink Eye
Conjunctivitis treatment would vary as per the cause of the conjunctivitis or pink eye. So for each type a different method of treatment is used.
Treatment for allergic conjunctivitis: Splashing cool water over the face with the head inclined downward (artificial tears) constricts capillaries and relieves itching in mild cases. In more severe cases, oral non-steroidal anti-inflammatory drugs (NSAIDs) and antihistamines are prescribed as well as some topical steroid drops.
Treatment of bacterial conjunctivitis: This is treated with antibiotic eye drops or ointments that cover a broad range of bacteria. However evidence suggests that this does not affect symptom severity and gains only modest reduction in duration of ailment. Hence, oral antibiotics are also prescribed.
Treatment for viral conjunctivitis: There is no specific treatment for viral conjunctivitis but in the olden times eyes were washed with milk to relieve the symptoms. Today, warm compresses and artificial tears to reduce the symptoms are used. In severe cases, topical corticosteroid drops are prescribed to reduce inflammation. Antibiotic drops are prescribed too for quicker recovery. Viral conjunctivitis can last from about 3 weeks to a month depending on the severity of the case.
Treatment for toxic conjunctivitis: Conjunctivitis caused by burns, toxins and chemicals in the eyes need to be washed out with saline, especially beneath the lids. Topical steroids may also be required. If neglected, the more acute chemical injuries, particularly alkali burns, can lead to severe scarring and intra-ocular damage. But this type of conjunctivitis is fortunately not very common.
Treatment for Chlamydia conjunctivitis: This is typically treated with erythromycin for most cases. Sometimes, tetracycline is used, except in children less than 8 years of age because of possible discoloration of the teeth.
Treatment of conjunctivitis due to other diseases: Here the other underlying disease e.g. rheumatoid arthritis, which is the cause of the conjunctivitis, has to be treated in order to cure conjunctivitis.
Living with Pink Eye
Pink eye or Conjunctivitis is an affliction causing a lot of discomfort. While the symptoms exist, the person is temporarily helpless and disabled. Sore and red eyes, puffy eyes, watery eyes, runny nose, discharge, earache, eye pain, itching, etc can be very inhibiting. Doing ones daily chores and activities itself becomes a major difficulty. But, the symptoms wear off with treatment and they last for a very short period of time. Also, pink eye is not life-threatening, although due care needs to be taken not to lose ones eyesight from neglect.
Prevention of Pink Eye
Pink eye or conjunctivitis can be prevented by various measures.
1) Don’t share towels and napkins;
2) Avoid touching your eyes frequently;
3) Disinfect surfaces like countertops, sinks, and doorknobs;
4) Wash your hands thoroughly after touching a child’s infected eye for administering medication;
5) Avoid personal contact with a person having conjunctivitis till their infection is cured.
