Ocular Infections

Question 1

3 common causes of bacterial conjunctivitis in neonates?

Answer 1

Staph aureas
N. gonorrhoea
Chlaymydia trachomatous

all babies under 2 need referred to opthalmology

Question 2

3 common causes of bacterial conjunctivitis in adults / children ?

Answer 2

Staph aureas
Strep pneumoniae
H. influenza -esp kids

Question 3

antibiotic that covers most bacterial conjunctivitis?

Answer 3

Chloramphenicol

Question 4

alternative antibiotic for staph aureas in bacterial conjunctivitis?

Answer 4

fusidic acid

Question 5

Tx of bacterial conjunctivitis caused by coliforms?

Answer 5

gentamicin

Question 6

Tx of bacterial conjunctivitis caused pseudomonas aeruginosa?

Answer 6

gentamicin

Question 7

Tx for chlamydial bacterial conjunctivitis?

Answer 7

oxytetracycline

Question 8

potential S/Es of chloramphenicol

• common
• rare
• rare in babies

Answer 8

Allergy - red itchy eyes
Irreversible anaplastic anaemia
Grey baby syndrome (hypotension and cyanosis in young babies)

Question 9

effect of chloramphenicol on staph …

bactericidal or bacteriostatic???

Answer 9

bacteriostatic for staph

bacterocidal for step + H. influenza

Question 10

“follicular grains of rice” in a lower eyelid is probably a sign of … ?

Answer 10

chlamydial conjunctivitis
Often CHRONIC in young adults
They may not have any of the GU symptoms

Question 11

3 common viral causes of conjunctivitis?

whats most common?

Answer 11

adenovirus - #1 common
herpes simplex
herpes zoster

Question 12

how does adenovirus conjunctivitis present?

Answer 12

pink eye
watery
no discharge

Question 13

what is keratitis?

Answer 13

infection of the cornea

Question 14

potential causes of non-infective conjunctivitis?

Answer 14

#1 is allergy
toxic
autoimmune
neoplastic
reaction to contact lenses

Question 15

how would you detect keratitis on examination?

Answer 15

look for white corneal lesion

Question 16

how bad is bacterial keratitis?

Answer 16

it can be sight threatening

also normally only ever occurs alongside another pathology

Question 17

management of bacterial keratitis

Answer 17

1. admit

2. give eye drops every hour for 48 hours

Question 18

Tx for keratitis caused by most things: Gm +/- ?? (2)

Answer 18

gentamicin

cefuroxime

Question 19

what is the public health problem with Ofloxacin?

Answer 19

it is being over-used for corneal ulcers so developing resistance

Question 20

what does ofloxacin cover?

Answer 20

Gm - organisms
not strep pneumoniae
used for bacterial keratitis

Question 21

how does herpatic keratitis present?

Answer 21

green eyes!!
dendritic corneal ulcers!!
very painful!!
recurrent!!

Question 22

Tx of herpetic keratitis?

Answer 22

(antiviral)

Aciclovir - esp if have dendritic corneal ulcers

Question 23

what happens if you use steroids for herpatic keratitis?

Answer 23

corneal melt + perforation woo

Question 24

most common cause of keratitis

Answer 24

viral — adenovirus

Question 25

How does adenoviral keratitis present? - Hx - sign O/E

Answer 25

Hx of URTI Subepithelial infiltraties commonly bilateral cause so contagious

Question 26

what fungal infection causes keratitis in people who wear contacts?

Answer 26

ACANTHOMOEBA a - can - tho - moeba

Question 27

2 causes of fungal keratitis?

Answer 27

acanthamoeba - contacts | pseudomonas aeruginosa - dodgy water sources + soil

Question 28

dangerous complication of orbital cellulitis?

Answer 28

compartment syndrome | Orbital only - not preseptal

Question 29

5 common causes of orbital cellulitis (all quite standard)

Answer 29

``` staph strep coliforms H. influenza anaerobes ```

Question 30

common recent Hx of orbital cellulitis - where has infection come from?

Answer 30

Paranasal sinusitis

Question 31

management of orbital cellulitis??

Answer 31

CT for an abscess Assess if any damage to the nerves, or any muscle restriction G.A and drainage

Question 32

What is endophthalmitis?

Answer 32

infection of the whole eye very painful + red sudden onset - typically post-surgery NORMALLY commensal - #1 is staph epidermidis

Question 33

Tx of endophthalmitis?

Answer 33

Inreavitreal (into eye) antibiotics - vancomycin - cefrazidime - amikacin + topical antibiotics +/- systemic antibiotics

Question 34

what is chorioretinitis?

Answer 34

Chorioretinitis is an inflammation of the choroid (thin pigmented vascular coat of the eye) and retina of the eye. It is a form of posterior uveitis

Question 35

3 causes of chorioretinitis | - 1 rare in UK

Answer 35

rare = CMV (cytomegalovirus) in AIDS Toxoplasma gondii Toxocara canis

Question 36

tell me about toxoplasma gondii

Answer 36

A CAUSE OF CHORIORETINITIS 1. protozoan nematode 2. cats and raw meat 3. get mild flu symptoms 4. normally no complications so no Tx 5. if immunocompromised = get cysts

Question 37

tell me about toxocara canis

Answer 37

A CAUSE OF CHORIORETINITIS 1. parasitic nematode 2. cats and dogs 3. stays in worm form 4. rare - forms granulomas causing irreversible vision loss

Question 38

what kind of sample is taken if you suspect bacterial keratitis?

Answer 38

corneal scrape

Question 39

what kind of sample do you take if you suspect endopthalmitis?

Answer 39

culture of aqueous / vitreous

Question 40

what samples do you take for chorioretinitis? (different for each)

Answer 40

acanthamoeba = microscopy / contact lense culture toxoplasma / toxocara = serology

Question 41

what antibiotic "action" does chloramphenicol do? inhibit. ... - protein synthesis? - nucleic acid synthesis? - cell wall synthesis?

Answer 41

protein synthesis !!

Question 42

what is dacrocystitis?

Answer 42

lacrimal system gets blocked up + swollen due to infection.

Question 43

2 bacterial causes of anterior uvieitis ? 2 viral causes?

Answer 43

TB + syphilis herpes S + Z

Question 44

pain photophobia hypopyon keratic precipitates what am I?

Answer 44

anterior uveitis

Question 45

what is blepharitis?

Answer 45

infection of the eyelids | generally similar to conjunctivitis with grit + mild discharge

Question 46

what causes anterior blepharitis? (2) whats the difference in presentation?

Answer 46

staphylococcal - ulcers (styes) and trichiasis (ingrown eyelashes) seborrheic - dandruff + chalaxia cysts. 50% have acne rosacea.

Question 47

what eye condition is associated with acne rosacea?

Answer 47

sebhorreic blepharitis

Question 48

what presents with a white corneal lesion?

Answer 48

bacterial keratitis