Blepharitis

Blepharitis refers to inflammation of the eyelid margins.

Blepharitis refers to inflammation of the eyelid margins and may be divided into two types:

• Anterior blepharitis: affects the eyelashes. Most commonly due to seborrhoeic dermatitis and bacterial infections (e.g. Staphylococcus).
• Posterior blepharitis: affects the meibomian glands. These line the posterior eyelid margin and secrete the lipid part of the tear film.

Blepharitis most commonly presents as a chronic condition. The mean age of affected patients is 50 years old. It is a clinical diagnosis based on the history and examination with the most common symptoms being a gritty or burning sensation in both eyes, crusted eyelashes, red eyes, and swollen or greasy eyelids. The condition is managed with a combination of conservative treatment (e.g. lid hygiene) and medical treatment (e.g. ocular lubricants).

Blepharitis is a common condition.

Blepharitis accounts for at least 5% of ophthalmological presentations in primary care. Blepharitis can affect all ages but is most commonly seen in middle-aged individuals with the average age of presentation 50 years old. Women are more likely to develop Staphylococcal blepharitis compared to men, while other forms of blepharitis affect the sexes equally.

The causes of blepharitis can be divided into anterior and posterior.

The causes of blepharitis differ depending on whether it is anterior or posterior.

Anterior Blepharitis

The two predominant causes of anterior blepharitis are Staphylococci infection and Seborrhoeic type

• Staphylococcus blepharitis: pathophysiology remains unclear, but the mechanism is thought to involve damaging effects of bacterial exotoxin production and cell-mediated immunity. Females are more commonly affected than males
• Seborrhoeic blepharitis: closely linked with the common skin condition seborrhoeic dermatitis (present in ~95% of people with seborrheic blepharitis). Characterised by less inflammation than staphylococcal blepharitis, but more oily skin and scaling

Other infections that can lead to anterior blepharitis include: Pseudomonas, Streptococci, Propionibacterium, Corynebacterium, Moraxella

Posterior Blepharitis

Posterior blepharitis is also known as meibomian gland dysfunction (MGD).

In health, meibomian glands produce an oil called meibum. Meibum forms the outer layer of the tear film. The oil assists in reducing tear evaporation from the ocular surface. The underlying pathophysiology of MGD / posterior blepharitis is thought to be epithelial hyperkeratinisation, which results in gland obstruction, stasis of meibum, dilation of glands, and gland dropout. Some chronic skin conditions such as seborrhoeic dermatitis and rosacea can predispose to posterior blepharitis (not just anterior!).

The clinical features of blepharitis are typically red, swollen, or itchy eyes.

Blepharitis typically leads to chronic, recurrent eye symptoms and is commonly associated with dry eyes.

Symptoms

The symptoms associated with blepharitis are often bilateral.

• Sore, gritty, itchy, or burning eyes
• Eyelids sticking together on waking
• Worse in the morning
• Exacerbated by contact lenses, wind, makeup
• Dry eyes: light sensitivity, watery eyes, redness, blurred vision, contact lens discomfort

It is important to enquire about extra-ocular symptoms linked to associated conditions (particularly chronic skin conditions) that may include oily skin, flaky scalp or facial rash.

Signs

The severity of symptoms does not always match the examination findings (of which there may be none).

• Inflamed lid skin
• Reddened eyelid margins
• Crusting around the eyelid margins
• Deficient tear film

The cornea may be affected by severe disease with features of epithelial erosions, ulcerations, and scarring.

Specific signs

Some clinical signs are more specific to either anterior or posterior blepharitis

Anterior:

• Eyelash deformity / in-turning of lashes (trichiasis)
• Eyelash depigmentation (poliosis)
• Eyelash loss (madarosis): if localised, consider sebaceous gland carcinoma which may be misdiagnosed as chronic blepharitis

Posterior:

• Dilated meibomian glands
• Obstructed meibomian glands
• Telangiectasia: dilated blood vessel
• Chalazion: non-tender bump on the eyelid

Blepharitis is a clinical diagnosis.

Blepharitis is a clinical diagnosis based on a detailed history and examination (including slit-lamp). Routine investigations are typically not required. However, in severe or treatment-resistant cases, a swab for microscopy, culture, and sensitivity can be useful.

Persistent unilateral eyelid inflammation is concerning for possible malignancy. In these cases, a biopsy is critical.

A wide number of differentials should be considered in patients with suspected blepharitis.

• Conjunctivitis and other infections (e.g. impetigo, cellulitis, herpes simplex)
• Trauma
• Lid tumours: have a strong suspicion in unilateral presentations
  • Benign (e.g. actinic keratosis, squamous cell papilloma, sebaceous gland hyperplasia)
  • Malignant (e.g. basal cell carcinoma, squamous cell carcinoma, sebaceous gland carcinoma)
• Atopic/contact dermatitis
• Psoriasis
• Erythema multiforme
• Contact lens / foreign body-related
• Dry eye syndrome

Blepharitis is a long-term condition that requires regular lid hygiene and avoidance of exacerbating factors.

There are a variety of treatment options for blepharitis but the main focus should be on good lid hygiene, environmental changes, and the use of ocular lubricants for dry eyes.

When a diagnosis is confirmed, patients should be appropriately counselled. Blepharitis is a chronic condition and there is no ‘quick fix’. While a course of antibiotics may be a management option, it is unlikely to benefit a patient if not used in conjunction with other long-term measures including regular lid hygiene and avoidance of exacerbating factors. It is important to treat any co-existing conditions, particularly skin conditions.

Conservative management

Patients should be given advice on self-care measures for the eyes. These include:

• Regularly cleaning and massaging lids
• Warm compresses
• Avoidance of eye make-up (particularly eyeliner)
• Avoidance of contact lenses
• Wrap around glasses
• Avoid wind

Dietary changes are interesting and there is some evidence to suggest consuming omega-3 and omega-7 fats can improve dry eye disease and contribute to the ocular surface and meibomian gland health.

Pharmacological therapy

Ocular lubricants can be advised, particularly for patients with dry eyes. In general, thicker lubricants are used at night, with artificial eye drops used during the day. These are generally reserved for patients with mild-to-moderate symptoms.

In patients with more severe or refractory disease antibiotics and steroids can have a role.

• Antibiotics: topical agents may be considered first with oral agents reserved for cases with an inadequate response to topical therapy
• Steroids: these should only be prescribed by a consultant ophthalmologist. Usually given topically. Evidence for use is inconclusive and increases the risk of cataracts and glaucoma

Ophthalmology referral

A referral to an ophthalmologist for specialist review should be considered in the following patients:

• Treatment-resistant blepharitis
• Painful eye with blurred vision (suggests corneal involvement)
• Rapid onset or gradual visual loss
• Signs of orbital/pre-septal cellulitis
• Eyelid deformity (consider malignancy)
• A suspected underlying condition (e.g. Sjogren’s syndrome or ocular pemphigoid)
• Uncertain diagnosis
• Low threshold for referring children

Dry eye disease is one of the most frequent complications of blepharitis.

• Meibomian cyst (chalazion)
• External stye (hordeolum)
• Eyelash abnormalities: loss of eyelashes (madarosis), change in direction to point inwards (trichiasis), depigmentation (poliosis)
• Entropion (eyelid turning inwards)
• Ectropion (eyelid turning outwards)
• Dry eyes
• Contact lens intolerance
• Conjunctivitis
• Keratitis (inflammation of the cornea)