Blepharitis

Question 1

What is blepharitis?

Answer 1

Chronic eyelid margin inflammation with acute exacerbations.

Question 2

Types of blepharitis?

Answer 2

Anterior
Posterior
Mixed

Question 3

Aetiology of anterior blepharitis

Answer 3

Causes by bacteria - staphylococcal
(1) direct infection
(2) reaction to the staphylococcal exotoxin
(3) allergic response to the staphylococcal antigen.

Seborrheic - disorder of ciliary sebaceous glands of Zeis.

Demodex - infestation of the lash follicles.

Question 4

Aetiology of posterior blepharitis

Answer 4

Leading cause of evaporative dry eyes
caused by meibomian gland dysfunction
- bacteria lipases break down meibomian lipids
- meibomian secretions are physically and chemically abnormal
- plugging of duct orifices with abnormal lipids leading to dilatation of glands and causing chalazion, microliths
- tear film unstable

Question 5

Aetiology of mixed blepharitis

Answer 5

has elements of both posterior and anterior

Question 6

Link between blepharitis and dry eyes?

Answer 6

50% of people with blepharitis have dry eyes.
evaporative dry eye leading causing is MGD
dry eye in 25-40% with seborrheic bleph.

Question 7

predisposing factors?

Answer 7

long term CL wear
ocular rosaeca
seborrheic dermatitis
demodicosis - demodex brevis found in MGs, and demodex folliculorum found in lash follicles.

Question 8

Symptoms?

Answer 8

Can be asymptomatic
Ocular discomfort, soreness, burning, watering, itching
Eyelid itching - noted more in demodex infections
Symptoms of dry eyes such as blurred vision and CL intolerance.

Question 9

Signs of anterior blepharitis?

Answer 9

Staphylococcal
- Lid margin crusting, scaly deposits on base of lashes.
- Lid margin hyperaemia and swelling.
- Secondary signs - loss of lashes, misdirection of lashes, recurrent styes and chalazion, punctate epithelial erosion on lower third of cornea, neovasc/pannus, marginal keratitis, mild papillary conjunctivitis.

Seborrheic
- Lid margin hyperaemia
- Oily greasy deposits on lashes or base of lashes, lid margins.

Demodex
- Cylindrical dandruff collarettes on base of lashes extending up lashes more than the normal rosettes seen in blepharitis.
Persistent infection can cause trichiasis, loss of lashes, misdirection of lashes.

Question 10

Signs of posterior blepharitis?

Answer 10

MGD most common cause
Thick and opaque secretions from MG, difficulty expressing with finger pressure
Plugging of duct orifices
Unstable tear film, evaporative dry eye
Foam in Lower tear meniscus
Lid and conjunctival hyperaemia
Corneal involvement in some - lower third corneal punctate epithelial erosions, neovasc.pannus, scarring, marginal keratitis. papillae conjunctivitis.

Question 11

Non-pharmacological management?

Answer 11

Education on condition - chronic, complete eradication of symptoms not possible, long term compliance important to reduce symptoms and flare-ups

Lid hygiene routine is first line measure - hot compresses, massage, cleansing - wet warm compresses to loosen collarettes in anterior bleph, dry warm compresses to melt meibum in posterior bleph. Min 2x/day for at least 5 mins at 40 degrees of constant heat - electronic heating devices can be used, or eye bags.

Lid cleansing wipes are effective in removing bacteria and reducing signs and symptoms but long term compliance is poor.

Treat dry eyes if present e.g. drops during day, ointment before bed.

IPL for posterior blepharitis can be effective

Avoid cosmetics like eyeliner and mascara during exacerbations.

Question 12

Pharmacological management?

Answer 12

If first line measurements fail, consider topical antibiotics:
- Chloramphenicol ointment twice daily rubbed into lid margins with finger.
- Azithromycin 2x.day for 3 days.

Oral antibiotics for posterior blepharitis can be effective:
- Oral tetracycline e.g. doxycycline 100mg twice daily for 2 weeks then twice daily for 2-3/12 - contraindicated in under 12s and pregnancy/lactating women.
- Consider oral erythromycin (250-500mg every 6 hours, keep duration as short as possible) or azithromycin when tetracycline contraindicated

Tea tree oil in low concentrations to reduce chance of ocular toxicity for demodex infestation. Apply with eyes closed.

Short term topical steroid for severe cases.

Question 13

When to refer?

Answer 13

Normally no referral but if non-resolving, very symptomatic and tried all options available, consider routine referral.

Unilateral cases where meibomian gland carcinoma is suspected should be referred urgently.