Inflammation of the conjunctiva (thin protective outer layer of the eye)1. In some instances both the conjunctiva and the cornea (transparent covering of the eye, beneath the conjunctiva may become inflamed. This is known as kerato-conjunctivitis.
Causes of the disease
Common causes are infections of the eye. (especially in children.) Infective conjunctivitis is most commonly caused by bacteria (eg staphylococci) which are spread by hand to eye contact. Viruses associated with colds, sore throat or illnesses ( eg measles) may also contribute to the spread of conjunctivitis. Viral conjunctivitis can occur in epidemics, and spread rapidly through small populations.
New born babies are known to be susceptible to the disease. This is known as neonatal ophthalmia. This is due to the infectious organisms present in the mothers cervix infecting the baby during child birth. Organisms responsible for gonorrhea, herpes and chlamydial infection are often responsible for the infection. Infection may spread to the entire eye and cause blindness 2.
People who suffer from constant dry eye problems are at a high risk of contracting conjunctivitis. The tear glands located at the base of the eye are responsible for "wetting" the eye with many anti-bacterial compounds produced by the gland.
If the eye is infected by micro-organisms, the other eye too has a very high chance of developing a subsequent infection. This will soon appear a few days after the first eye is infected. Infections can usually be transmitted by the simple act of touching the eye. Thus the bacteria or virus will be present of the fingers and will spread to whatever objects the fingers come in contact with.
Associated conditions
Some types of allergies may be linked with this condition. This is especially common in adults. Of particular interest is the association of hay fever with conjunctivitis. In children, conjunctivitis is linked with infections of the respiratory tract 3. Constant exposure to harmful substances may also trigger an allergic reaction which eventually leads to signs of conjunctivitis 4.
Symptoms
Symptoms of conjunctivitis include 1 :
Redness of the eye (due to inflammation)
Discomfort.
A discharge from the affected eye.
(this may appear as a crustiness or a viscous fluid.)
Affected eye may be itchy.
Epidemiology
Very common disease. 20 people in 1000 visit their doctors each year because of conjunctivitis.
Diagnosis
The diagnosis is made mainly from a careful medical and family history and the apearance of the eye. A cotton swab of the eye may be taken if an infection is suspected. This swab may then be sent to a pathologist who will culture the bacteria and identify the organism responsible 5. This will aid in the treatment of the disease.
Ophthalmic lavage (washing of the eye with a solution) can be performed to obtain a solution which can then be analysed for the presence of immunoglobulins (proteins involved in the immune system, albumin (protein present when the eye is infected and neutrophils (white blood cells.) These can all indicate the presence or absence of ac infection or allergic reaction
