Ophth microbiology

Question 1

organisms that are seen in neonatal bacterial conjunctivitis

Answer 1

S aureus
Neisseria gonorrhea
Chlamydia trachomatis

Question 2

refer all cases of neonatal conjunctivitis to phthalmology as likely cause = an __

Answer 2

STI

Question 3

bacterial causes of conjunctivitis

Answer 3

S. aureus
H. influenzae (esp in kids)
strep pneumoniae

Question 4

treatment for bacterial conjunctivitis

Answer 4

swab for culture

chloramphenicol unless allergy/ Hx of aplastic anaemia

Question 5

signs of adenoviral conjunctivitis

Answer 5

very watery red eye, usually bilateral

after URTI

Question 6

signs of a bacterial conjunctivitis

Answer 6

red eye, mucousy discharge

perhaps blurred vision

Question 7

Herpes simplex conjunctivitis signs =

Answer 7

unilateral usually
maybe blistering rash on eyelid
maybe a dendritic ulcer

Question 8

HZX sign that indicates nasociliary branch of ophthalmic nerve is affected

Answer 8

Hutchinson’s sign - vesicles on tip of nose

Question 9

three signs that conjunctivitis may be due to chlamydia

Answer 9

chronic Hx
bilateral and unresponsive to Rx
in young adults

Question 10

pathognomonic sign of chlamydial conjunctivitis

Answer 10

lymphatic collections in follicles on underside of eyelids = “rice grains”

Question 11

bacterial keratitis s+S

Answer 11

large white lesion which stains with fluorescein (corneal ulcer)
hypopyon

Question 12

bacterial keratitis is usually associated with another ____/___

Answer 12

corneal pathology (eg. reduced sensation)
contact lenses

Question 13

hypopyon =

Answer 13

white accumulation at bottom of iris

leukocytic exudate in anterior chamber

Question 14

treatment for bacterial keratitis =

Answer 14

hrly drops (tobramycin-fortified or gentamicin-fortified) high risk
moderate risk = topical quinolone
low risk = topical polymyxin B/trimethoprim or sulfacetamide ophthalmic

Question 15

herpetic keratitis is ___ on first occurrence and then on recurrences = ___
signs =

Answer 15

very painful
reduced corneal sensation
vision reduced acutely
dendritic ulcers

Question 16

signs of adenoviral keratitis

Answer 16

subepithelial infiltrates (small and white) = blurred vision
bilateral
post URTI

Question 17

___ usually only causes keratitis is contact lens users who swim

Answer 17

acanthamoeba

Question 18

__+__ are organisms that cause keratitis in contact lens wearers

Answer 18

acanthamoeba

pseudomonas aeruginosa

Question 19

s+S of orbital cellulitis

Answer 19

painful (esp on eye movements)
proptosis
ass w paranasal sinusitis often
pyrexial
sight threatening

Question 20

if suspect orbital abscess then imaging =

Answer 20

CT

Question 21

in optic nerve compression __ vision is first to go

Answer 21

colour vision

Question 22

chalazion =

Answer 22

stye

Question 23

dacrocystitis

Answer 23

blocked tear duct

Question 24

__+__ - the two types of orbital cellulitis

chich do you watch closely

Answer 24

pre-septal

orbital - watch closely

Question 25

organisms that cause orbital cellulitis

Answer 25

staph strep coliforms h influ anaerobes

Question 26

Rx for orbital cellulitis

Answer 26

broad spectrum Abx

Question 27

image orbital cellulitis if __/___

Answer 27

muscular or nerve dysfunction

Question 28

endophthalmitis =

Answer 28

devastating infection of the whole eye globe

Question 29

usual cause of endophthalmitis =

Answer 29

post-op

Question 30

s+s of endophthalmitis

Answer 30

v v painful reduced vision v red eye sight threatening

Question 31

most common org of endophthalmitis = | org.s are usually ___ of the conjunctiva

Answer 31

S. epidermidis | commensals

Question 32

treatment of endophthalmitis

Answer 32

prophylactic Abx during eye Sx | intravitreal amikacin and vancomicin + topical Abx

Question 33

3 causes of chorioretinitis

Answer 33

CMV in IS/AIDs toxoplasma gondii - reactivates in IC toxocara canis =>granuloma and irreversible vision loss

Question 34

corneal scrapes are used to diagnose

Answer 34

bacterial keratitis

Question 35

swabs for culture from eye are used to diagnose

Answer 35

bacterial, chlamydial and viral conjunctivitis

Question 36

aqueous/vitreous for culture is used to diagnose ___

Answer 36

endophthalmitis

Question 37

microscopy/culture of eye is used to diagnose ___

Answer 37

acanthamoeba and contact lens cases

Question 38

serology of eye to diagnose __+___

Answer 38

toxocara | toxoplasma

Question 39

chloramphenicol inhibits _____ bactericidal for __+__ bacteriostatic for ____ side effects =

Answer 39

peptidyl transferase - bac protein formation Strep + H influ staph allergy, irreversible aplastic anaemia, grey baby syndrome

Question 40

__+___ attack bacterial cell wall = bacterio___ for __+__ treatment

Answer 40

penicillins and cephalosporins cidal cellulitis and dacrocystitis

Question 41

keep eye drop bottles for up to __ as if longer then __

Answer 41

4 wks | contaminated esp by pseudomonas

Question 42

antiviral used for dendritic ulcers of the cornea

Answer 42

aciclovir 3% drops

Question 43

don't give steroids for a dendritic ulcers as can cause __/___

Answer 43

corneal melt and perforation

Question 44

Rx for bacterial conjunctivitis

Answer 44

``` chloramphenicol (for most except pseudo aeruginosa) fusidic acid (S. aureus) gentamicin (gram -ves - including P. aeruginosa) ```

Question 45

Rx for chlamydial conjunctivitis =

Answer 45

topical oxytetracycline (+PO azithromycin for genital inf)

Question 46

treatment for bacterial keratitis =

Answer 46

4- quinolone ofloxacin - most gram -ves but not strep pneum | gentamicin and cefuroxime - combo for most +ve and -ves