keratitis

Question 1

what is keratitis?

Answer 1

Keratitis describes inflammation of the cornea. Microbial keratitis is not like conjunctivitis - it is potentially sight threatening and should therefore be urgently evaluated and treated.

Question 2

bacterial causes

Answer 2

typically Staphylococcus aureus
Pseudomonas aeruginosa is seen in contact lens wearers

Question 3

causes general

Answer 3

bacterial
fungal
amoebic
parasitic
viral
environmental

Question 4

amoebic causes?

Answer 4

acanthamoebic keratitis
increased incidence if eye exposure to soil or contaminated water
pain is classically out of proportion to the findings

Question 5

parasitic causes?

Answer 5

onchocercal keratitis (‘river blindness’)

Question 6

viral cause

Answer 6

herpes simplex keratitis

Question 7

environmental causes

Answer 7

photokeratitis: e.g. welder’s arc eye
exposure keratitis
contact lens acute red eye (CLARE)

Question 8

features?

Answer 8

red eye: pain and erythema
photophobia
foreign body, gritty sensation
hypopyon may be seen

Question 9

referral for who?

Answer 9

assessing contact lens wearers who present with a painful red eye is difficult
an accurate diagnosis can only usually be made with a slit-lamp, meaning same-day referral to an eye specialist is usually required to rule out microbial keratitis

Question 10

mx?

Answer 10

stop using contact lens until the symptoms have fully resolved
topical antibiotics
typically quinolones are used first-line
cycloplegic for pain relief
e.g. cyclopentolate

Question 11

complications?

Answer 11

corneal scarring
perforation
endophthalmitis
visual loss