Conjunctivitis is an inflammation (swelling) of the conjunctiva. The conjunctiva is the transparent membrane that covers the white part of the eyeball and the inner surfaces of the eyelids. There are four main types.

The most prevalent is Bacterial Conjunctivitis, caused by Staphylococci / Streptococci bacteria which can exist on one’s own skin or respiratory tract or indeed be contracted from another individual. Commonly it gives a yellowish gunky discharge from the eyelids, resulting in a crusty dandruff like residue at the base of the eyelashes. The eyes will generally be itchy/red and in some cases the lids can be stuck together after a nights sleep. Approximately 64% of cases will resolve spontaneously after five days, the remainder will require broad spectrum antibiotic drops/ointment eg. Chloramphenicol, Fucithalmic.

Viral Conjunctivitis is most commonly associated with the common cold (caused by adenovirus) and can spread rapidly between people.   In this case, the eyes are red, uncomfortable and give a more watery discharge. It can also affect the cornea (keratitis) and may persist for several weeks

Although no direct treatment, eye lubricants eg. Lacrylube and antibiotic drops (to prevent a secondary bacterial infection) can be used. In severe cases, steroid drops may be issued by an eye specialist. A strict code of hand/face washing and not sharing towels needs to be adhered to.

Allergic Conjunctivitis is generally associated with the atopic reactions of eczema, asthma and hayfever being caused by antigens such as dust mites, pollen etc. It is treated with antihistamine drops, but occasionally steroids may be required. Less commonly, there is Chlamydial Conjunctivitis, which can be associated with Venereal disease.

The various types of conjunctivitis, although similar, do display their own subtle traits and if unsure, a specimen/swab can pinpoint the precise aetiology. This is particularly important with babies and young children due to their poorer immune systems.

Noel McCrystal
BSc.(Hons.)MCOptom.Dip.Sc.V MASv.P

Download Article PDF