Lec 3 Red Eye 2

Question 1

Differentials for bacterial keratitis

Answer 1

Sterile/marginal keratitis

Fungal keratitis

Acanthamoeba keratitis

Viral HSV/adenovirus keratitis

Question 2

Pathophysiology of pseudomonas aeriginosa for CL related bacterial keratitis

Answer 2

ABLE to attach to epithelium as it’s stuck on CL surface and held against epithelium (some strains can invade intact)

Exotoxins/enzymes released causing perforation

Question 3

Pathophysiology of staphylococcus aureus for CL related bacterial keratitis

Answer 3

Staph exoproteins promote host response and this response is destructive to own tissues

Question 4

Treatment of bacterial keratitis

Answer 4

Refer if >2mm/central/sight threatening

Mono therapy ciprofloxacin 0.3%

Cycloplegia 1% cyclo gel rid till inflammation gone

FML

Question 5

Describe monotherapy for bacterial keratitis

Answer 5

Ciprofloxacin 0.3% loading 1 drop q5min for 15 min

Then q30min for 24 hrs and review after

Improved=taper min if qid and continue few days after resolve

No improvement = refer

Question 6

Differentials for viral keratitis

Answer 6

Adenovirus keratitis

Heroes simplex keratitis

Molluscum contagiousness (sheds virus particles = inflam resp)

Chlamydial conjunctivitis

Question 7

Differentials for pseudodendrites

Answer 7

Healing epithelial abrasion

Herpes zoster ophthalmicus

Acanthamoeba in CL wearers

Question 8

How to treat HSV keratitis

Answer 8

Only manage small/non sight threatening dendritic ulcer

Ophthalmic acyclovir 3% ointment - Virupos
- 10mm ribbon in forbid 5x/day for 10-14 days including 3 days after resolution

Question 9

How to treat recurrent HSV keratitis (with scarring)

Answer 9

Refer ophthal

• epithelium disease controlled = give topical corticosteroids to control inflammation
• oral acyclovir tabs 400mg 2x/day to reduce recurrence rate (NOT Subsidised)

Question 10

How to treat fungal keratitis

Answer 10

Urgent referral to ophthal as resistant to treatment

Question 11

Risk factors for acanthamoeba

Answer 11

Tap or spa water

CL wear

Poor hygiene/trauma???

Question 12

Signs of acanthamoeba

Answer 12

Epithelial/subepithelial infiltrates (snowstorm)

Pseudodendrites

Limbitis (gets misdiagnosed as HSV here)

Wessely Ring (stromal ring infiltrate) with epithelial lesion

Hypopyon, episcleritis, scleritis, corneal thinning to perforation

Question 13

Differentials for acanthamoeba

Answer 13

HSV keratitis

Adenoviral Keratitis

Bacterial keratitis

Fungal keratitis

Question 14

What are 2 investigations you can do for acanthamoeba

Answer 14

In vivo confocal microscopy at green lane

Corneal scrape before treatment using:

• light microscopy with calcofluor white stain to find cysts
• culture in non nutrient agar with E. Coli to find trophozoites

Question 15

What is the main ophthalmology treatment for acanthamoeba

Answer 15

After positive diagnosis by microscopy:

Combination therapy:

• promadine isethionate 1% Brolene q1hr
• PHMB 0.02% q1hr OR chlorhexidine 0.02% as alternative

After 3 days reduce to q2hr by day and treat till satisfactory (months)

Question 16

What are other treatments offered for acanthamoeba

Answer 16

Cycloplegia

Oral NSAID

Topical corticosteroid to manage inflammation

Penetrating Keratoplasty ultimately if uncontrolled

Question 17

How to manage episcleritis

Answer 17

Support: advice, artificial tears

Diclofenac 0.1% voltaren optha qid for up to 4 wks
OR
FML 0.1% qid for 1 wk and stop

Question 18

How to treat scleritis ( non-necrotising and necrotising)

Answer 18

Non necrotising
- oral NSAID or systemic corticosteroid (refer)

Necrotising (BV occluded leading to stromal necrosis)
- urgent referral to ophthal

Question 19

How to manage subconjunctival haemorrhage

Answer 19

Spontaneously resolves:

• reassure and give artificial tears
• cold then warm compress

BUT if trauma check angle recession, orbital fracture, conjunctiva lesion or retina

Question 20

How to manage acute angle closure

Answer 20

1. Topical therapeutics e.g Pilocarpine (<45mmhg), beta blocker, alpha agonist, CAI
2. Systemic therapeutics e.g Acetazolamide 500mg initially OR Mannitol (hyper osmotic agent)

PI!!

Cataract surgery!!!