Blepharitis is caused by a number of different contributory factors and can present as a mild, acute or chronic inflammatory condition, affecting the eyelash, eyelid rims and both the outside and underside of the eyelids. Little is understood about the reasons for blepharitis and the condition is divided into either ulcerative or non-ulcerative forms. The cause of ulcerative blepharitis can be an infection (e.g. Bacterial/staphylococcal) or a virus (e.g. Herpes simplex/Varicella Zoster), while causes of non-ulcerative blepharitis are generally allergic reactions, perhaps to contact lens solution or eye makeup.
Additional causes of the condition include:
- Clogged/dysfunctional oil glands in the eyelids
- Rosacea (the skin condition that causes patches of facial redness)
- Eyelash lice/mites
- Scalp and eyebrow dandruff
In addition to the two classifications already discussed (ulcerative/non-ulcerative), blepharitis also presents in three main types. These are:
- Anterior blepharitis (affecting the base of the eyelashes)
- Posterior blepharitis (affecting the margins/rims of the eyelids)
- Mixed blepharitis (affecting both the base of the eyelashes and the margins/rims of the eyelids)
Anterior blepharitis has more than one possible cause. It can be sparked by a reaction to staphylococcus bacteria. These bacteria are found on many of us without ever causing symptoms or harm; the reasons why they trigger blepharitis in some of us are unknown. Another possible cause of anterior blepharitis is seborrhoeic dermatitis, a condition characterised by oily/flaky skin and blocked glands.
Posterior blepharitis is caused by is caused by the the upper and/or lower eyelid glands (known as the Meibomian glands) becoming blocked by flakes of skin, debris and/or inflammation. This is where the link with rosacea comes into play because rosacea is associated with blockages in the eyelid glands.
Mixed blepharitis is caused by a mix of the issues associated with anterior and posterior blepharitis.
Who has more chances of getting Blepharitis?
While everyone has some bacteria on their bodies, some people have bacteria at the foot of the eyelashes. Furthermore, while the oil glands in the eyelids perform satisfactorily in most of us, in some of us they become blocked. People with either or both of these issues are more likely to experience blepharitis.
Your risk of blepharitis is at its highest during childhood and then again once you’re over 50. Most sufferers experience episodes of symptoms followed by periods of reprieve and so the condition is eminently treatable and manageable. Knowing about the causes is an important component of your treatment regimen. Becoming acquainted with the various parts of the eye and their names (e.g cornea, conjunctiva, Meibomian glands) is another helpful undertaking.
Since there is no one-off cure for blepharitis, becoming as informed as possible will make a big difference to the efficacy of your treatment.
Although blepharitis is usually not serious, it can have knock-on effects, including dry-eye syndrome (when an insufficient amount of tears are generated by the eyes or the eyes simply dry to quickly). Consequently, dry/gritty/sore eyes become a daily reality. However, if the complications of the condition are dealt with promptly, it is unlikely ever to be a serious problem or a threat to eyesight.