Conjunctiva Flashcards
Name two viruses commonly causing conjunctivitis.
- Adenoviruses (multiple serotypes)
2. Herpes viruses
What is conjunctivitis?
Describes any form of conjunctival inflammation, but usually refers to bacterial or viral infection.
Name 6 bacteria commonly causing conjunctivitis.
- Staph aureus
- Staph epidermidis
- Strep pneumoniae
- H. Influenzae
- Neisseria gonorrhoeae (esp. in neonates)
- Chlamydia trachomatis
Name 7 causes of red eye.
- Infective conjunctivitis
- Allergic conjunctivitis
- Trauma
- Iritis
- Episcleritis
- Corneal problems (corneal ulceration should be excluded).
- Trauma
How does bacterial conjunctivitis manifest? 9 features listed.
- Sticky, red eye of acute onset
- Generally associated with mild to moderate itching
- May have burning or grittiness
- Little or no effect on vision (discharge may cause mild blurring)
- May be unilateral initially, but fellow eye follows suit shortly after
- Lid swelling
- Conjunctival hyperaemia
- Purulent discharge
- Papillae (flat bumps, usually on palpebral conjunctivae)
Management of bacterial conjunctivitis?
Most self-limiting within a few days with no Rx or Ix necessary.
However, prescription of a broad-spectrum topical Abx, such as chloramphenicol, is usual.
If infection fails to respond to topical Abx, a conjunctival swab is sent for microscopy and culture is helpful, but a viral cause is more likely.
Conjunctivitis often accompanies blepharitis, which requires treatment.
What features of bacterial conjunctivitis warrant referral to an ophthalmologist?
- Atypical features
- Particularly severe or persistent infection (eg. neisseria gonorrhoeae - can penetrate corneal epithelium and cause corneal infection. Mx is intensive specific antibiotic Rx).
How does chlamydial conjunctivitis characteristically present?
In young adults as an acute or subacute follicular conjunctivitis, clinically similar to a viral infection. Urethral or vaginal symptoms may occur.
How would you investigate and treat chlamydial conjunctivitis?
Microscopy, immunofluorescence and culture of conjunctival scrapes aid diagnosis.
Rx: oral Abx, tetracycline or erythromycin.
(Note: tetracycline unsuitable in neonate because of discolouration of growing teeth; use systemic erythromycin).
Differentiate the two types of chlamydia trachomatis eye infection.
- Inclusion conjunctivitis (serotypes D-K), sexually transmitted.
- Trachoma (serotypes A-C), endemic to areas with inadequate sanitary facilities. Chronic course leading to severe conjunctival cicatricial change with entropion, trichiasis, dry eye and secondary corneal ulceration and scarring. Trachoma is the third most common cause of blindness worldwide. Dx and Rx similar to chlamydial inclusion conjunctivitis.
True or false: conjunctival involvement cannot occur in the course of systemic childhood viral infections like measles and chicken pox.
False.
What is the main distinguishing symptomatic feature between bacterial and viral conjunctivitis? Plus another.
- Viral conjunctivitis has a watery discharge rather than purulent (although, night-time discharge causes the eyelids to be sticky in the morning).
- Viral has conjunctival follicles resembling grains of rice (vs papillae in bacterial).
Name some features of viral conjunctivitis. 9 listed.
- Watery discharge
- Conjunctival hyperaemia
- Unilateral progressing to bilateral involvement
- Moderate grittiness typical
- Frequently, petechial conjunctival haemorrhages
- Conjunctival follicles (resembling grains of rice).
- Punctate corneal epithelial erosions are frequent (corneal ulcerstion, such as the dendritic lesions of herpes simplex keratitis, should be excluded). Microscopic subepithelial corneal infiltrates may develop under the epithelial erosions and result in glare, which can persist following resolution of the acute conjunctivitis.
- Pre-auricular lymph node enlargement frequently present.
- Eyelid swelling, possibly severe enough to close the lids together and may extend down the face to the ear.
Can ophthalmic shingles cause conjunctivitis?
Yes. Characteristic skin changes may be mild and easily overlooked.
What is a follicular conjunctivitis caused by and how is it treated?
May be caused by viral particles shed from the lesion of molluscum contagiosum, a tiny whitish papillomatous lump on the eyelid margin that is easily treated by curettage.
In general, how is (non-severe) viral conjunctivitis treated?
Usually settles within about 2 weeks without treatment (also, specific Rx for majority of viral cases not available).
Symptoms of irritation, redness and stickiness after sleep may persist for months.
In refractory cases, Ix by means of conjunctival swabs and scrape is indicated. May identify an alternative organism such as chlamydia, or may suggest a distinct inflammatory process.
Two treatments for herpes simplex conjunctivitis?
Topical aciclovir and trifluorothymidine are effective.
Which conjunctivitis can cause epidemic infection?
Adenoviral.
Personal hygiene and avoidance of contact should be practised.
What are some treatments used in treating symptoms of viral conjunctivitis?
Vasoconstrictor/antihistamine combinations may reduce sx.
Topical Abx may be prophylactic against secondary bacterial infections.
Artifical tears can be soothing.
Topical steroids effectively reduce sx, but should only be used in cases where dx is certain and under ophthal supervision.
Neonatal conjunctivitis within the first few hours of birth is usually caused by what?
Usually chemically induced.
Thereafter, chlamydia and other bacteria likely.
Rapidly progressive disease suggests more serious infection like N gonorrhoea. Corneal examination is mandatory.
What are two conditions which may mimic neonatal conjunctivitis?
- Congenital glaucoma
2. Congenital nasolacrimal duct obstruction
Can ophthalmic shingles cause conjunctivitis?
Yes. Characteristic skin changes may be mild and easily overlooked.
What is a follicular conjunctivitis caused by and how is it treated?
May be caused by viral particles shed from the lesion of molluscum contagiosum, a tiny whitish papillomatous lump on the eyelid margin that is easily treated by curettage.
In general, how is (non-severe) viral conjunctivitis treated?
Usually settles within about 2 weeks without treatment (also, specific Rx for majority of viral cases not available).
Symptoms of irritation, redness and stickiness after sleep may persist for months.
In refractory cases, Ix by means of conjunctival swabs and scrape is indicated. May identify an alternative organism such as chlamydia, or may suggest a distinct inflammatory process.
Two treatments for herpes simplex conjunctivitis?
Topical aciclovir and trifluorothymidine are effective.
Which conjunctivitis can cause epidemic infection?
Adenoviral.
Personal hygiene and avoidance of contact should be practised.
What are some treatments used in treating symptoms of viral conjunctivitis?
Vasoconstrictor/antihistamine combinations may reduce sx.
Topical Abx may be prophylactic against secondary bacterial infections.
Artifical tears can be soothing.
Topical steroids effectively reduce sx, but should only be used in cases where dx is certain and under ophthal supervision.
Neonatal conjunctivitis within the first few hours of birth is usually caused by what?
Usually chemically induced.
Thereafter, chlamydia and other bacteria likely.
Rapidly progressive disease suggests more serious infection like N gonorrhoea. Corneal examination is mandatory.
What are two conditions which may mimic neonatal conjunctivitis?
- Congenital glaucoma
2. Congenital nasolacrimal duct obstruction
What are the four chief features of acute allergic conjunctivitis?
- Rapid onset. Settles spontaneously after a few hours.
- Itching
- Lid swelling
- Conjunctival oedema (chemosis)
In whom is acute allergic conjunctivitis mostly seen?
In children following exposure to pollen or some other allergen that has been inoculated into the conjunctival fornices.
May also occur in response to the administration of topical eye medication (though signs tend to resemble a contact dermatitis with variable skin erythema and excoriation).
Name six features of seasonal allergic conjunctivitis.
- Occurs in association with hayfever at times of high environment pollen count
- Mild to moderate itching
- Redness
- Watering
- Mucous discharge
- Conjunctival papillae
What is useful for immediate relief in acute allergic conjunctivitis?
Topical vasoconstrictor/antihistamine. Topical antihistamine example includes levocastabine. Systemic antihistamine (eg. terfenadine) can be used acutely as well as prophylactically. Severe cases may warrant weak topical corticosteroids under ophthalmic supervision.
Name two treatments which are prophylactic against acute allergic conjunctivitis (one of them is also used acutely):
- Topical sodium cromoglycate (and related nedocromil) stabilie mast cells.
- Terfenadine (systemic antihistamine, also used acutely)
What do the terms “vernal” and “atopic keratoconjunctivitis” mean?
They both refer to a spectrum of chronic allergic conjunctivitis.
Vernal keratoconjunctivitis occurs in children, atopic keratoconjunctivitis in adults.
Both are caused by repeated exposure to allergen in association with immune system dysfunction.
Seasonal exacerbations are frequently a feature.
Ulceration and infiltration of the upper part of the cornea is a feature of what?
Vernal keratoconjunctivitis.
What are six features of vernal/atopic kerstoconjunctivitis?
- Itching
- Burning
- Grittiness
- Redness
- Stringy mucous discharge
- Large or even ‘giant’ papillae
What is the treatment of vernal/atopic keratoconjunctivitis?
Similar to that of seasonal allergic conjunctivitis, though topical steroids are more often required.
What is Stevens-Johnson syndrome?
Also known as erythema multiforme major, it is an acute systemic vasculitis involving the skin and the oral and conjunctival mucous membranes. Mortality is significant.
What are some of the features of Stevens-Johnson syndrome conjunctivitis?
Bilateral, moderate to severe conjunctivitis is common.
With bullae and necrotic patches, progressing to extensive conjunctival scarring.
Name 5 diseases that feature corneal filaments.
- Keratoconjunctivitis sicca
- Recurrent corneal erosion syndrome
- Corneal anaesthesia (neurotrophic keratopathy)
- Herpes simplex keratitis
- Superior limbic keratoconjunctivitis
Filaments are strands of epithelium and mucous that attach to pinpoint defects in the epithelium.
Name a chronic relapsing/remitting autoinflammatory disorder of the conjunctiva which results in secondary corneal shrinkage (cicratisation).
Ocular cicatricial pemphigoid.
Name two conditions which may result in severe mechanical abnormalities of the lids including entropion and trichiasis, with secondary corneal scarring that may eventually lead to blindness.
- Stevens-Johnson syndrome
2. Ocular cicatricial pemphigoid
What may be an effective treatment in ocular cicatricial pemphigoid?
Dapsone.
Other forms of systemic immunosuppression are sometimes tried.
True or false: penetrating keratoplasty for corneal scarring carries a poor prognosis.
True.
Surgical insertion of a prosthetic cornea (keratoprosthesis) may offer the only chance of restoring sight in advanced disease.
Superior limbic keratoconjunctivitis is associated as one of the ocular manifestations of which systemic disease? And where are signs restricted to?
Dysthyroid eye disease.
Restricted to superior bulbar conjunctiva (injection), superior limbus (thickened and vascularised) and upper third of the cornea (filamentary keratitis, where filaments are strands of epithelium and mucous that attach to pinpoint defects in the epithelium).
What is conjunctivitis called when it occurs during the first postnatal month?
Ophthalmia neonatorum.
Because the usual causes are special to this age group, it is regarded as distinct from conjunctivitis occurring in older infant.
A neonatal chlamydial conjunctivitis may present with which three extraocular manifestations?
- Pneumonitis
- Rhinitis
- Otitis
Which three microorganisms may be acquired by the child during vaginal delivery, associated with maternal sexually transmitted disease? Plus name another 3 which are common.
- Chlamydia trachomatis
- Herpes simplex virus
- Neisseria gonorrhoea
However, staph, strep and H. Influenzae are also common in the neonate (though not from maternal genitourinary infection).
State the interval between birth and onset of inflammation for: chlamydia; gonococcus; herpes simplex; staph & other bacteria; chemical (all causes of ophthalmia neonatorum).
Chlamydia: 1-3 weeks
Gonococcus: first week
Herpes simplex: 1-2 weeks
Staph & other bacteria: end of first week onwards
Chemical: first few days (eg. Topical antiseptic causing conjunctival hyperaemia).
Name the types of discharge for: chlamydia; gonococcus; herpes simplex; staph & other bacteria; chemical (all causes of ophthalmia neonatorum).
Chlamydia: mucopurulent Gonococcus: severe purulent (beware gonococcal keratitis) Herpes simplex: watery Staph & other bacteria: purulent Chemical: nil/watery
Which investigations are performed in ophthalmia neonatorum?
- Conjunctival swabs for microscopy including chlamydial immunochemistry, and for chlamydial, bacterial and viral culture.
- Conjunctival scrape
- Fluid from skin vesicles for viral culture (suspect HSV)
If chlamydia suspected, swabs are also taken from extraocular sites such as esrs, throat and rectum
General treatment for ophthalmia neonatorum? Chlamydial? HSV? Gonococcal? Severe but dx uncertain?
If no corneal involvement and no rapidly progressive severe infection, a broad-spectrum topical antibiotic such as chloramphenicol or fusidic acid.
Chlamydia: oral erythromycin for two weeks (oral tetracycline CI in children as stains growing teeth).
HSV: Topical and systemic aciclovir.
Gonococcus: benzylpenicillin or a cephalosporin.
If dx unsure and infection severe/rapidly progressive, take a range of samples and treat with cefuroxime (to ensure gonococcal cover). Baby reviewed daily.
Ddx of a watery eye with little redness and sticky discharge in a neonate?
- Conjunctivitis
- Nasolacrimal duct obstruction
- Orbital cellulitis (ddx of severe conjunctivitis - very occasionally, a bacterial conjunctivitis can develop into a cellulitis affecting the superficial tissues (‘preseptal’ cellulitis) or the orbit itself).
