Blepharitis

Blepharitis is a subacute or chronic inflammation of the lid margins.

Blepharitis may be subdivided into anterior and posterior although there is considerable overlap and both are often present. The poor correlation between symptoms and signs, the uncertain aetiology and mechanisms of the disease process all conspire to make management difficult.

Chronic anterior blepharitis

Chronic marginal blepharitis is a very common cause of ocular discomfort and irritation.
Involvement is usually bilateral and symmetrical.

Anterior blepharitis affects the area surrounding the bases of the eyelashes and may be staphylococcal or seborrhoeic.

1. Ulcerative blepharitis / bacterial blepharitis

• It is a chronic staphylococcal infection of the lid margin usually caused by coagulase positive strains.
• The disorder usually starts in childhood and may continue throughout life.
• Chronic conjunctivitis and dacryocystitis may act as predisposing factors.

It is thought to be the result of an abnormal cell mediated response to components of the cell wall of S. aureus which may also be responsible for the red eyes and the peripheral corneal infiltrates seen in some patients.

Symptoms.

• These include chronic irritation, itching, mild lacrimation, gluing of cilia, and photophobia.
• The symptoms are characteristically worse in the morning.
• Burning, grittiness, mild photophobia, and crusting and redness of the lid margins with remissions and exacerbations are characteristic.
• Symptoms are usually worse in the mornings although in patients with associated dry eye they may increase during the day.

(Symptoms do not provide a reliable clue to the type of blepharitis and are caused by disruption of normal ocular surface function and reduction in tear stability. Because of poor correlation between the severity of symptoms and clinical signs it can be difficult to objectively assess the benefit of treatment.) 

Signs.

• Yellow crusts are seen at the root of cilia which glue them together.
• Hard scales and crusting mainly located around the bases of the lashes (collarettes)
• Small ulcers, which bleed easily, are seen on removing the crusts.
• In between the crusts, the red thickened anterior lid margin may show dilated blood vessels (rosettes).
• Mild papillary conjunctivitis and chronic conjunctival hyperaemia are common.
• Long-standing cases may develop scarring and notching (tylosis) of the lid margin, madarosis, trichiasis and poliosis. Secondary changes include stye formation, marginal keratitis and occasionally phlyctenulosis.
• Associated tear film instability and dry eye syndrome are common.

2. Seborrhoeic or squamous blepharitis

• Seborrhoeic blepharitis is often associated with generalized seborrhoeic dermatitis that may involve the scalp, nasolabial folds, behind the ears, and the sternum.
• It is usually associated with seborrhoea of scalp (dandruff).
• Some constitutional and metabolic factors play a part in its etiology.
• In it, glands of Zeis secrete abnormal excessive neutral lipids which are split by Corynebacterium acne into irritating free fatty acids.

Symptoms. 

Patients usually complain of deposition of whitish material (soft scales)at the lid margin
associated with mild discomfort, irritation, occasional watering and a history of falling of eyelashes. 

Signs.

• Hyperaemic and greasy anterior lid margins with sticking together of lashes
• Accumulation of white dandruff-like scales are seen on the lid margin, among the lashes.
  (The scales are soft and located anywhere on the lid margin and lashes.)
• On removing these scales underlying surface is found to be hyperaemic (no ulcers).
• The lashes fall out easily but are usually replaced quickly without distortion.
• In long-standing cases lid margin is thickened and the sharp posterior border tends to be rounded leading to epiphora.

Complications and sequelae:

These are seen in long- standing (non-treated) cases and include: 

• chronic conjunctivitis,
• madarosis (sparseness or absence of lashes), trichiasis ( misdirected cilia), poliosis (greying of lashes),
•  tylosis (thickening of lid margin) and
•  Eversion of the punctum leading to epiphora.
• Eczema of the skin and ectropion may develop due to prolonged watering.
• Recurrent styes is a very common complication.
• Because of the intimate relationship between the lids and ocular surface, chronic blepharitis may cause secondary inflammatory and mechanical changes in the conjunctiva and cornea.

Treatment

There is little evidence to support any particular treatment protocol for anterior blepharitis.

It should be treated promptly to avoid complication and sequelae.

Patients should be advised that a permanent cure is unlikely, but control of symptoms is usually possible.

1. Lid hygiene is essential at least twice daily. 

Includes:

• Warm compresses applied for 5-10 minutes to soften crusts at the bases of the lashes. 
• Crust removal and lid margin cleaning.
  (Lid cleaning to mechanically remove crusts involves scrubbing the lid margins once or twice daily with a cotton bud dipped in a dilute solution of baby shampoo or 3% sodium bicarbonate.)
  (Commercially produced soap/alcohol impregnated pads for lid scrubs are available but care should be taken not to induce mechanical irritation.) 
• The eyelids can also be cleaned with diluted shampoo when washing the hair. 
• Gradually, lid hygiene can be performed less frequently as the condition is brought under control but blepharitis often recurs if it is stopped completely. 
• Following lid hygiene the ointment should be rubbed onto the anterior lid margin with a cotton bud or clean finger. 
• Avoid rubbing of the eyes or fingering of the lids. 

2. Antibiotic

• Antibiotic ointment should be applied at the lid margin, immediately after removal of crusts, at least twice daily.
• Antibiotic eye drops should be used 3-4 times a day.
• Topical sodium fusidic acid, bacitracin or chloramphenicol is used to treat acute folliculitis but is of limited value in long- standing cases.
• Oral azithromycin (500 mg daily for three days) may be helpful to control ulcerative lid margin disease.
• Oral antibiotics – erythromycin or doxycycline may be useful in unresponsive cases or with stye/abcess of lash follicles.

3. Topical steroid (Weak) such as fluorometholone 0.1% Q.I.D. for one week is useful in patients with severe papillary conjunctivitis, marginal keratitis and phlyctenulosis although repeated courses may be required.

4. Ocular lubricants i.e artificial tear drops are required for associated tear film instability and dry eye.

5. General measures include improvement of health and balanced diet.

6. Associated seborrhoea of the scalp should be adequately treated with Local measures include removal of scales from the lid margin with the help of lukewarm solution of 3 percent soda bicarb or baby shampoo and frequent application of combined antibiotic and steroid eye ointment at the lid margin.

Chronic posterior blepharitis

Posterior blepharitis is caused by meibomian gland dysfunction and alterations in meibomian gland secretions.

Bacterial lipases may result in the formation of free fatty acids. This increases the melting point of the meibum preventing its expression from the glands, contributing to ocular surface irritation and possibly enabling growth of S. aureus. Loss of the tear film phospholipids that act as surfactants results in increased tear evaporation and osmolarity, and an unstable tear film.

Meibomitis

 i.e inflammation if meibpmian glands occurs in chronic and acute forms

1. Chronic meibomitis (MGD)

Chronic meibomitis is a meibomian gland dysfunction, seen more commonly in middle-aged persons, especially those with acne rosacea and seborrhoeic dermatitis.

1 Symptoms- chronic irritation, burning, itching ,grittiness , mild lacrimation with remission and exacerbations intermittently. Symptoms are characteristically worse in the morning.

2 Signs

• white frothy (foam-like) secretion frequently seen on the eyelid margins and canthi (meibomian seborrhoea).
  (Excessive and abnormal meibomian gland secretion manifest as capping of meibomian gland orifices with oil globules.)
• Pouting, recession, or plugging of the meibomian gland orifices.
• At the lid margin, openings of the meibomian glands become prominent with thick secretions
• Which can be expressed out by pressure on lids giving tooth paste appearance.
  (Pressure on the lid margin results in expression of meibomian fluid that may be turbid or toothpaste-like; in severe cases the secretions become so inspissated that expression is impossible.) 
  
• Lid transillumination may show gland loss and cystic dilatation of meibomian ducts.
• On eversion of the eyelids, vertical yellowish streaks shining through the conjunctiva are seen.suggestive of meibomian glands filled with thick secretions.
• Hyperaemia and telangiectasis of the posterior lid margin around the orifices of meibomian glands.
• The tear film is oily and foamy, and froth may accumulate on the lid margins or inner canthi. 
• Secondary changes include papillary conjunctivitis and inferior corneal punctate epithelial erosions. 

2. Acute meibomitis 

It occurs mostly due to staphylococcal infection. It is characterized by painful swelling around the involved gland. Pressure on it results in expression of pus bead followed by serosanguinous discharge.

Treatment

It is very important to inform the patient that a cure is unlikely.
Although remission may be achieved recurrence is usual, particularly when treatment is stopped prematurely.

1. Lid hygiene is essential. 

at least once a day. Includes: 

• Warm compresses for several minutes.
• the emphasis is on massaging the lid to express accumulated meibum.
• Expression of accumulated secretions by repeated vertical massage of lids in the form of miking.
• (Massaging toward the lid margin edge to 'milk' meibum and physical expression of the glands)

2. Topical therapy involves

Topical antibiotics 

• in the form of eye ointment should be rubbed at lid margin after massage,
• eye drops may be used 3-4 times a day.

Topical steroids (weak) such as fluoromethalone – required in patients with papillary conjunctivitis

Ocular lubricants i.e tear substitutes for associated tear film instability and dry eye.

3. Systemic tetracyclines are the mainstay of treatment because their ability to block staphylococcal lipase production. ( at well below the minimum inhibitory antibacterial concentration.)
(but should not be used in children under the age of 12 years or in pregnant or breast-feeding women because they are deposited in growing bone and teeth, and may cause staining of teeth and dental hypoplasia)
(erythromycin is an alternative)

• Doxycycline 100 mg b.d. for one week and then o.d. daily for 6-12 weeks.
• Oxytetracycline 250 mg b.d. for 6-12 weeks.
• Minocycline 100 mg daily for 6-12 weeks; skin pigmentation may develop after prolonged use.
• Erythromycin 250 mg daily or b.d. May be used in children

Associations of chronic blepharitis

1. Tear film instability is found in 30-50% of patients, probably as a result of imbalance between the aqueous and lipid components of the tear film allowing increased evaporation. Tear film break-up time is typically reduced.

2. Chalazion formation, which may be multiple and recurrent, is common, particularly in patients with posterior blepharitis.

3. Epithelial basement membrane disease and recurrent epithelial erosion may be exacerbated by posterior blepharitis.

4. Cutaneous
· Acne rosacea is often associated with meibomian gland dysfunction.
· Seborrhoeic dermatitis is present in >90% of patients with seborrhoeic blepharitis.
· Acne vulgaris treatment with isotretinoin is associated with the development of blepharitis in about 25% of patients; it subsides when the treatment is stopped.

5. Bacterial keratitis is associated with ocular surface disease secondary to chronic blepharitis.

6. Atopic keratoconjunctivitis is often associated with staphylococcal blepharitis. Treatment of the blepharitis often helps the symptoms of allergic conjunctivitis and vice versa.

7. Contact lens intolerance. Long-term contact lens wear is associated with posterior lid margin disease. Inhibition of lid movement and the normal expression of meibomian oil may be the cause. There may also be associated giant papillary conjunctivitis making lens wear uncomfortable. Blepharitis is also a risk factor for contact lens-associated bacterial keratitis

	Feature	Anterior blepharitis		Posterior blepharitis
		Staphylococcal	Seborrhoeic
Lashes	Deposit	Hard	Soft
	Loss	++	+
	Distorted or trichiasis	++	+
Lid margin	Ulceration	+
	Notching	+		++
Cyst	Hordeolum	++
	Meibomian			++
Conjunctiva	Phlyctenule	+
Tear film	Foaming			++
	Dry eye	+	+	++
Cornea	Punctate erosions	+	+	++
	Vascularization	+	+	++
	Infiltrates	+	+	++
Associated disease		Atopic dermatitis	Seborrhoeic dermatitis	Acne rosacea

Parasitic blepharitis (lash infestation)

Blepharitis associated with infestation of lashes by lice in person living in poor hygienic conditions.

Phthiriasis palpebrarum refers to the infestation by phthirus pubis (crab louse).

• It is more commonly seen in adults in whom it is usually acquired as a sexually transmitted infections.
• It is an infestation of lashes which typically affects children living in poor hygienic conditions.
• The crab louse Phthirus pubis is adapted to living in pubic hair
• An infested person may transfer the lice to another hairy area such as the chest, axillae or eyelids.

Pediculosis refers to the infestation by pediculus human corporis or capitis (head louse).
If heavily infested the lice may spread to involve lashes.

1 Symptoms:

•  consist of chronic irritation and itching of the lids; burning and mild lacrimation .

2 Signs:

• Lid margins are red and inflamed.
• Lice - anchored to the lashes by their claws. – may be seen on slit lamp examination
• Nits (eggs) ova and their empty shells seen as oval, brownish, opalescent pearls adherent to the base of the cilia.
• Conjunctival congestion and follicles may be seen in long standing cases.
• Conjunctivitis is uncommon.

3 Treatment

• Mechanical removal of the lice, nits and their attached lashes with fine forceps.
• Application of antibiotic ointment and
• Topical yellow mercuric oxide 1% or petroleum jelly applied to the lashes and lids twice a day for 10 days.
• Delousing of the patient, family members, clothing and bedding is important to prevent recurrences.

Angular blepharitis

1 Pathogenesis 

The infection is usually caused by Moraxella lacunata or S. aureus  although other bacteria, and rarely herpes simplex, have also been implicated. 

2 Signs

• Often unilateral
• red, scaly, macerated and fissured skin at the lateral and medial canthus
• Associated papillary and follicular conjunctivitis may occur.

3 Treatment

•  involves topical chloramphenicol, bacitracin or erythromycin.

Childhood blepharokeratoconjunctivitis

Childhood blepharokeratoconjunctivitis is a poorly defined condition which tends to be more severe in Asian and Middle Eastern population.

1 Presentation is usually at about 6 years of age with recurrent episodes of chronic redness and irritation that results in constant eye rubbing and photophobia which may be misdiagnosed as allergic eye disease.

2 Signs

• Chronic anterior or posterior blepharitis which may be associated with recurrent styes or meibomian cysts.
• Conjunctival changes include diffuse hyperaemia, bulbar phlyctens and follicular or papillary hyperplasia.
• Corneal changes include superficial punctate keratopathy, marginal keratitis, peripheral vascularization and axial subepithelial haze. 

3 Treatment

• Lid hygiene and topical antibiotic ointment at bedtime.
• Topical low dose steroids (prednisolone 0.1% or fluorometholone 0.1%).
• Erythromycin syrup 125 mg daily for 4-6 weeks.