Microbiology & the eye Flashcards Preview

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Flashcards in Microbiology & the eye Deck (51):
1

What is inflammation of the entire globe called?

Endophthalmitis

2

What are the common causes of bacterial conjunctivitis in neonates?

Staph. aureus
Neisseria gonohhoeae
Chylamydia trachometis

3

What are the most common causative organisms in bacterial conjunctivitis in not neonates?

Staph. aureua
Strep. pneumoniae
Haem. influenzae (esp. children)

4

Treatment of bacterial conjunctivitis

Usually self limiting but if needed cholramphenicol

5

When should chloramphenicol be avoid?

History of aplastic anaemia or allergy

6

How is viral conjunctivitis different from bacterial clinically?

Watery rather than mucousy discharge

7

How does a viral conjunctivitis usually present?

Usually starts with URTI
Watery discharge

8

Causes of viral conjunctivities

Adenovirus
Herpes Simplex
Herpes zoster

9

What is Hutchin-Robinsons sign?

Sports on end of nose - Herpes zoster infection of trigeminal nerve (virus sits in ganglion then comes out at times of stress)

10

When should chlamydial conjunctivitis be suspected?

Bilateral conjunctivitis in young adults

11

What other symptoms may accompany chlamydial conjunctivitis?

Urethritis
Vaginitis

12

What is bacterial keratitis usually associated with?

Other corneal pathology or conact lens wear

13

Management of bacterial keratitis

Need admission for hourly drop

14

What is a hypopyon?

White blood cells & inflammatory material in anterior chamber

15

Typical presentation of bacterial keratitis with hypopyon?

Painful
Reduced vision
White mark in red eye (URGENT!!)

16

What 2 virus most commonly cause keratitis?

Herpes simplex
Adenoviral

17

Presentation of herpetic keratitis

Very painful
Can be recurrnt
Recurrences eventually result in reduced corneal sensation

18

Why should herpetic keratitis not be treated with steroids?

Can cause corneal melt and perforation of the cornea

19

Presentation of adenoviral keratitis?

Bilateral
Following URTI
Contagious
May affect vision

20

Management of adeoviral keratitis

May be given topical AB to prevent secondary bacteria infection

21

What keratitis is associated with washing lenses in ta water?

Acanthamoeba

22

Typical features of pseudomonas aeruginosa keratitis

Farmers/gardeners
In eyes that have other problems
Takes a long time to heal

23

Presentation of orbital cellulitis

Painful (especiialy on eye movements)
Proptosis
Often associated with paranasal sinusitis
Pyrexial

24

First line investigation in suspected orbital cellulitis

CT scan

25

What is dacrocystitis?

Infection of the lacrimal sac

26

Organisms that cause orbital cellulitis

Staphylococci
Streptococci
Coliforms
Haem. influenzae
Anaerobes

27

What is endophthalmitis?

Devastating infection inside the eye usually due to blunt trauma

28

Presentation of endophthalmitis

Painful ++++
Decreasing vision
Very red eye

29

Organisms that cause endophthalmitis

Often conjunctival "commensals"
Most common is staph epidermis

30

Treatment of endopthalmitis

Intravitreal amillacin and vancomysin and topical antibiotics

31

What virus causes chlororetinitis in AIDs patients?

CMV

32

What rotozoan infection causes chlororetinitis?

Toxoplasma gondil

33

Treatment of toxoplasma gondil

Self limiting but would want to treat if close to disc

34

What parasitic infection can cause chlororetinitis?

Toxocara canis (worm)

35

Are toxocara canis able to replicate in humans?

No

36

Why could toxocara be sight threatening?

Can form granulomas

37

How is enophthalmitis diagnosed?

Aqueous/vitreous cultue

38

How is acanthamoeba diagnosed?

Microscopy/culture

39

How is bacterial keratitis diagnosed?

Corneal scrape

40

What are the 3 types of swab?

Bacterial
Chlamydial
Viral

41

What is the mechanism of action of chloramphenicol?

Inhibits peptidyl transferase enzyme (sops bacterial protein being made)

42

Side effects of cholramphenicol

Allergy
Irreversible aplastic anaemia
Grey baby syndrome

43

When is the site of action of penicillins?

Bacterial cell wall

44

What is a common contaminant of eye drop bottles?

Pseudomonas

45

What problems can be caused by pseudomonas contaminant?

Corneal ulcer

46

Which bacteria is not treated by cholramphenicol?

Pseudomonas aeruginosa

47

Which bacteria does fusidic acid treat?

Staph aureus

48

What could treat bacterial onjunctivitis caused by pseudomonas aeruginosa??

Gentamicin

49

What is the management for chylamidial conjuntivtiis?

Topical oxytetracycline

50

First line treatment for bacterial keratitis

Ofloxacin

51

What bacteria does ofloxacin not treat?

Strep. pneumoniae