Ординатура / Офтальмология / Английские материалы / Moorfields Manual of Ophthalmology_Jackson_2007

Anterior Blepharitis

Background Includes two main types that may coexist: seborrhoeic and staphylococcal. Commonly complicated by meibomian gland dysfunction. See also posterior blepharitis (p. 114) and ocular rosacea (p. 116).

History Ask about ocular irritation, burning sensation, and lid margin erythema.

Examination

■Staphylococcal: dry, scaly lash debris, lid margin erythema, and pinpoint lid margin ulceration.

■Seborrhoeic: greasy lash debris (Fig. 4.5) and seborrhoea of the scalp, brows, and ears.

Treatment Advise lid hygiene : clean away the lash debris once or twice daily with a cotton-tipped bud dipped in boiled or sterile water (e.g. contact lens solution) or use proprietary lid cleaning pads made for the purpose. For staphylococcal disease prescribe Oc. chloramphenicol or Oc. fucithalmic b.d. to the lid margins for 3 weeks.

Follow-up One month if there is corneal involvement; otherwise, not routinely required.

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Posterior blepharitis

Posterior Blepharitis

Background A spectrum of disease from meibomian seborrhoea, through meibomianitis and meibomian conjunctivitis, to meibomian keratoconjunctivitis (ocular rosacea; next section). Bacterial enzymes (S. epidermidis, S. aureus, Propionibacterium acnes ) produce excessive free fatty acids and abnormal tear lipids that cause inflammation and irritation. Altered meibomian gland secretions contribute to meibomianitis. See also anterior blepharitis (p. 113) and ocular rosacea (p. 116).

History Chronic, non-specific symptoms include crusting of lashes (80%), ocular redness (80%), foreign body sensation (65%), chalazia (60%), blurred vision (45%), tearing (40%), and burning sensation (40%). The symptoms of meibomian seborrhoea are worse than the signs.

Examination

■Lids: meibomian seborrhoea has excessive meibomian secretions with little inflammation. With meibomianitis there are dilated, prominent meibomian gland orifices (100%), meibomian gland plugs (100%) and pouting meibomian gland orifices (35%) (Fig. 4.6). With time, partial lash loss (60%), lid notching (45%), and telangiectasia develop.

■Conjunctiva: diffuse injection (100%), papillary hypertrophy (100%), rose bengal uptake (100%), tear film debris (55%), reduced tear break up time (100%), and foamy tear film (60%).

■Cornea: in meibomian keratoconjunctivitis there is superficial punctate keratopathy (SPK) of the lower cornea (100%).

■Skin: look for seborrhoeic dermatitis, acne rosacea, or seborrhoeic sicca.

Treatment Emphasize that this is a chronic condition with no known cure and that indefinite treatment is often required. Advise lid hygiene:

1.Fill a wash basin with hot water. Soak a facecloth until comfortably hot, make into a ball and press firmly over the closed eye. Re-warm the face cloth as it cools. Continue for 5 minutes. Then;

2.Express stagnant meibomian gland secretions by massaging from top to bottom along the length of the upper lid (massage up in the lower eyelid). Then;

Fig. 4.6: Posterior blepharitis.

A course of antibiotic ointment (e.g. chloramphenicol or fucithalmic b.d. to the lid margins for 3 weeks) may help. For corneal involvement prescribe doxycycline 100 mg o.d. p.o. for 8 weeks to thin meibomian gland secretions and reduce excessive free fatty acids (contraindications include age <8 years and pregnancy). Alternatively, use erythromycin 250 mg q.d.s. p.o. for 8 weeks. Warn about the risk of sunburn when on tetracyclines. Consider short-term topical corticosteroids, e.g. prednisolone 0.5% b.d. 2 weeks in severe cases. Treat any dry eye and skin disease.

Follow-up For moderate to severe disease review routinely in clinic. Expect improvement in 2–3 months, then reduce lid hygiene to the minimum required to prevent symptoms.

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Ocular rosacea

Ocular Rosacea

Background A form of severe blepharo-keratoconjunctivitis more commonly seen in light-skinned people. See also anterior and posterior blepharitis (pp. 113 and 114).

History Similar to posterior blepharitis. May have facial flushing with alcohol or spicy food.

Examination The skin shows erythema, telangiectasia and pustules over the cheeks, nose, and forehead with thickening of the skin over the nose (rhinophyma) in the later stages (Fig. 4.7). The eye is involved in 60% of cases:

■Lids: posterior blepharitis, chalazia.

■Conjunctiva: variable diffuse injection ± small grey nodules on the bulbar conjunctiva near the limbus. These may ulcerate.

■Cornea: involved in 5% with superficial punctate keratitis

and peripheral ulceration that may progress to perforation,

± superficial and deep neovascularization, ± lipid keratopathy.

Treatment Eliminate spicy food and alcohol that exacerbate acne rosacea. Treat as for severe meibomian keratoconjunctivitis (p. 114).

Follow-up Depends upon the severity and response to treatment. Review corneal vascularization fortnightly until quiescent.

Bacterial Conjunctivitis

Background Bacterial conjunctivitis is most commonly caused by Staphylococcal and Streptococccal spp, or H. influenzae. Rare pathogens include Neisseria spp. and Chlamydia. For conjunctivitis of the newborn see page 572.

Symptoms Discharge with eyelids stuck together in the mornings, red eye, and ocular irritation. Usually starts in one eye then spreads to the other. Presentation may suggest the causative organism:

■Hyperacute (<12 hrs): N. gonorrhoeae, N. kockii, N. meningitides (rare).

■Acute: S. pneumoniae, H. aegyptius, Staphyloccal spp.

■Subacute: H. influenzae (thin watery discharge), E. coli,

Proteus spp.

■Chronic: Chlamydia.

Signs The lids may be mildly oedematous with tear film debris (Fig. 4.8). There is conjunctival injection ± papillae, or rarely a pseudomembrane or true membrane. Exclude corneal epithelial defects or ulceration. Lymphadenopathy is usually absent except with Chlamydia or gonococcus. Gonococcus can produce a secondary iritis.

Differential diagnosis Consider viral conjunctivitis (systemic viral features, less discharge, follicles), allergic conjunctivitis (atopy, itch, papillae), blocked nasolacrimal duct (look for reflux with pressure on a mucocele), blepharitis, and acute ocular cicatricial pemphigoid.

Investigations Consider sending conjunctival swabs for culture and sensitivity. For hyperacute, severe, purulent discharge or (pseudo-) membranes send urgent conjunctival scrapings for Gram stain. Inoculate onto blood agar and chocolate agar.

Treatment Advise patients to clean away discharge, wash hands, and avoid spreading infection to family and colleagues via towels or direct contact. Topical antibiotics, e.g. G. chloramphenicol q.d.s., may speed resolution. Avoid prolonged or repeated treatment that may cause drop allergy. G. prednisolone 0.5% q.d.s. may reduce the scarring often seen following pseudomembranous conjunctivitis but generally avoid steroid use. If microscopy shows Gram-negative intracellular diplococci treat for Neisseria with hourly G. chloramphenicol and i.v. cefotaxime 500 mg q.d.s. once, but check latest protocols with a sexually

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117

Adenoviral Keratoconjunctivitis

Background The most common acute viral infection of the external eye. Virus may spread systemically and shed via tears, resulting in secondary ocular infection. External spread may occur by aerosol or direct contact, e.g. hands and clinical instruments. Numerous viral serotypes can cause the disease.

History Incubation period is ≈8 days with three typical presentations:

■Acute non-specific follicular conjunctivitis : produces a red eye initially with mild irritation and tearing, but little photophobia. Lid swelling occurs after 48 hours. Usually bilateral, separated by 1–3 days. Usually resolves rapidly.

■Pharyngoconjunctival fever (PCF) : a follicular conjunctivitis with systemic viral features.

■Epidemic keratoconjunctivitis (EKC) : commonest in autumn and winter. Produces acute red eye, tearing, and irritation. There may be minimal systemic symptoms in adults but

children may get fever, sore throat, and ear ache. Bilateral in ≈40% with onset usually separated by 4–5 days.

Ask about contact with conjunctivitis, and systemic viral features such as myalgia, sore throat, cough, fever, and gastrointestinal disturbance.

Examination

■Tender preauricular lymphadenopathy.

■Lids: mild to moderate swelling.

■Conjunctiva: there is typically diffuse injection with variable chemosis and serous discharge, ± ecchymoses, ± petechial haemorrhages. Look for follicles (p. 110, Fig. 4.1) on the lower tarsal conjunctiva and papillary hyperplasia of upper tarsal conjunctiva. Pseudomembranes with mucopurulent discharge may occur, or rarely, true membranes.

■Cornea: variable involvement (30% in PCF, ≈80% in EKC). In the first week there may be fine pin-point epithelial erosions on retroillumination that do not stain with fluorescein or rose bengal and often resolve. In the second week there may be focal or diffuse, fine or coarse punctate keratitis that stains with fluorescein and rose bengal. There may be

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Adenoviral keratoconjunctivitis

Fig. 4.9: Adenoviral keratoconjunctivitis with subepithelial infiltrates.

punctate keratitis. Subepithelial infiltrates (Fig. 4.9) may occur in the visual axis, causing blurred vision and glare.

■Anterior chamber: may have a mild cellular reaction in the second week.

Wash hands and clean the slit-lamp after use. Do not routinely check IOP because of the risk of cross-infection.

Differential diagnosis Bacterial conjunctivitis (more discharge, fewer follicles, and no systemic viral features), acute haemorrhagic conjunctivitis caused by enterovirus 70, coxsackie A24, or Streptococcus pneumoniae (usually resolves within 2–4 days), and allergic conjunctivitis (more likely to have itch, atopy, and papillae). Papillae have a central vessel at their apex, whereas follicles have fine vessels around their base.

Investigations Swabs have a low yield but consider if the diagnosis is uncertain and onset within 12 days.

weeks during active viral replication. After this period, steroids probably do not alter the basic pathogenesis, but merely suppress inflammation. Subepithelial infiltrates may reappear when steroids are tapered off. These usually resolve with a second course of steroids.

Follow-up Most cases spontaneously resolve within 8–10 weeks, often sooner. Review those with keratitis in clinic and beware emergence of a true dendritic ulcer and steroid-responsive IOP elevation. Permanent visual loss is very rare but corneal subepithelial infiltrates may rarely recur for several years.

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Chlamydial Conjunctivitis

Chlamydial Conjunctivitis

There are three species of chlamydiae: C. trachomatis, C. psittaci, and C. pneumoniae. Almost all ocular disease is caused by

C. trachomatis with three distinct ocular syndromes: adult inclusion conjunctivitis (AIC), neonatal inclusion conjunctivitis (p. 572), and trachoma.

Adult inclusion conjunctivitis

Background Adult inclusion conjunctivitis (AIC) is a sexually transmitted infection (STI) caused by immunotypes D–K, producing urethritis, proctitis, epididymitis, and prostatitis in men; cystitis, cervicitis, salpingitis, and pelvic inflammatory disease in women. Spread is usually through direct contact with infected genital secretions, but also by direct eye-to-eye contact or by poorly chlorinated swimming pools.

Symptoms Acute or subacute onset of redness, irritation, mucopurulent discharge 2–19 days after inoculation. Initially unilateral, then bilateral.

History Assess the risk of a sexually transmitted infection.

Examination Look for conjunctival injection with welldeveloped follicles. Unlike trachoma, the inferior fornix is more affected than the superior fornix. There may be fine to coarse superficial punctate keratitis and a limited number of irregular subepithelial limbal infiltrates after several weeks. Check for preauricular lymphadenopathy.

Investigation Apply topical anaesthetic then scrape the tarsal conjunctiva with a spatula and apply to a glass slide for fluorescent monoclonal antibody testing (≈95% sensitivity, ≈85% specificity). Use tissue culture (70–90% sensitivity, 100% specificity) if legal ramifications are likely. Take bacterial and viral conjunctival swabs. Polymerase chain reaction (PCR)-based tests are replacing culture and antibody-based tests in many laboratories; samples must be taken before fluorescein is applied.