Conjunctivitis Flashcards
What are the main causative organisms for acute bacterial conjunctivitis?
Staphylococcus aureus
Strep Pneumonia
Haemophilus influenza
Neisseria gonorrhoea (rarer)
give some symptoms of bacterial conjunctivitis?
Unilateral red eye which become bilateral
Redness grittiness and purulent discharge
‘sticky’ eye on wakening
Hyperaemia (conjunctival injection)
Gonococcal is more severe and can cause lid oedema and lymphadenopathy as well
When self limiting treatment fails, how is bacterial conjunctivitis managed?
Topical chloramphenicol or fusidic acid
What serological variants of chlamydia cause adult inclusion conjunctivitis?
D-K
What investigations are appropriate for adult inclusion conjunctivitis and what might they show?
Giemsa stain - shows basophilic intracytoplasmic inclusion bodies
Direct immunofluorescence staining - free elementary bodies
Swab for culturing
What is the treatment for adult inclusion conjunctivitis?
1gram of azithromycin or 100mg of doxycycline for 14 days 2x daily
What are some of the features of adult inclusion conjunctivitis?
Red eye with mucopurulent discharge preauricular lymphadenopathy Follicles in inferior fornix Epithelial keratitis and sub epithelial corneal infiltrates Reiter syndrome
What is trachoma?
This is the lading cause of infectious blindness worldwide.
What serological variants cause trachoma?
A-C
What is the pathophysiology behind trachoma?
Type IV hypersensitivity
Active inflammatory stage and a cicatricial (scarring) chronic stage
Eventual blindness comes from the recurring infection and scarring.
What occurs in the active inflammatory phase of trachoma?
Follicular conjunctivitis
Vascularisation of the superior cornea
What occurs in the chronic cicatricial phase of trachoma?
Herbert pits Arlt's line Trichiasis Entropion Eventually corneal opacities may develop
How is trachoma managed? (SAFE)
Surgery for trichiasis
Antibiotics
Facial cleanliness
Environmental improvement
Define Ophthalmia neonatorum:
This in conjunctival inflammation durng the first 30 days of life. Most common causes are chlamydia and gonorrhoea.
other causes include HSV and Staph Aureus
How do you treat neonatal conjunctivitis?
Chlamydia - oral erythromycin
Gonorrhoea - IM ceftriaxone
HSV - aciclovir IV
Staphylococcal - Topical chloramphenicol
What is the most common cause of viral conjunctivitis?
Adenovirus
Then
HSV and molluscum contagiosum
What are the main types of viral conjunctivitis?
Acute non-specific follicular conjunctivitis (ANFC) (most commonly seen) Pharyngoconjunctival fever (PCF) Epidemic keratoconjunctivitis (EKC)
What adenoviral serotypes cause PCF and EKC
PCF - 3, 4, 7
ECK - 8, 19, 37
What are the four types of allergic conjunctivitis?
Seasonal & perennial
Vernal keratoconjunctivitis
Atopic keratoconjunctivitis
Giant papillary conjunctivitis
What causes seasonal and perennial allergic conjunctivitis and how is it managed?
Type 1 hypersensitivity IgE mediated response. Seasonal is worse in spring/summer while perennial is all year round
Avoid allergens
Anti histamines
Topical sodium Cromoglycate
What is giant cell conjunctivitis
A type 1 and 4 hypersensitivity reaction to lens wearing. Causes increased ocular tiredness when wearing lenses and is associated with pruritic red eyes and mucous secretions.
Define Pinguecula:
Bulbar conjunctival degeneration characterised by a white/yellow patch, commonly on the nasal limbus.
Never grows over the cornea
Risk factors - UV light and aging
Define Pterygium:
This is bulbar conjunctival degeneration characterised by a pink fleshy triangular shaped vascular wedge, usually on the nasal limbus, causing destruction of bowman’s layer and grows over the cornea.
What is a chronic blistering autoimmune disease which commonly affects elderly women, and is type 2 hypersensitivity response to autoantibodies attacking the basement membrane?
Ocular Mucous membrane pemphigoid
