Microbiology

Question 1

gram positive can be broken into what?

Answer 1

cocci and bacilli

Question 2

gram negative can be broken into what?

Answer 2

cocci
cocci-bacilli
bacilli

Question 3

name the 4 types of ‘itis’ in the eye

Answer 3

conjunctiva = conjunctivitis
cornea = keratitis
entire globe = endophthalmitis
skin/lymph = cellulitis

Question 4

what 3 things can cause conjunctivitis?

Answer 4

bacteria
virus
chlamydia

Question 5

Staph aureus, Neisseria gonorrhoeae and Chlamydia trachomatis all cause bacterial conjunctivitis in which age group?

Answer 5

neonates

Question 6

what 3 common pathogens cause bacterial conjunctivitis in other ages of patients?

Answer 6

staph aureus
strep pneumoniae
haemophilus influenzae (kids)

Question 7

bacterial conjunctivitis treatment:

Answer 7

swab

chloramphenical qds

Question 8

when should you avoid chloramphenicol?

Answer 8

history of aplastic anaemia or allergy

Question 9

what 3 viruses cause viral conjunctivitis?

Answer 9

adenovirus
herpes simplex
herpes zoster

Question 10

name the self limiting, contagious conjunctivitis that results in a watery eye?

Answer 10

adenoviral conjunctivitis

Question 11

which viral conjunctivitis is common in the young with milk spots around the eye?

Answer 11

herpes simplex viral conjunctiviits

Question 12

herpes zoster if on the nose is affecting which nerve?

Answer 12

naso-ciliary nerve

Question 13

suspect this in bilateral conjunctivitis in young adults unresponsive to treatments…

Answer 13

chlamydial conjunctivitis

Question 14

what is seen in chlamydial conjunctivitis on the subtarsal?

Answer 14

follicles and sub tarsal scarring

Question 15

what 3 things cause microbial keratitis?

Answer 15

bacteria
viruses
fungi

Question 16

what is often seen in bacterial keratitis that is white at the bottom of the cornea?

Answer 16

hypopyon

Question 17

bacterial keratitis treatment

Answer 17

admission for hourly drops

Question 18

what 2 viruses can cause microbial keratitis?

Answer 18

herpes or adenovirus

Question 19

what is the hallmark of herpetic keratitis?

Answer 19

dendritic ulcer

Question 20

what do you not treat dendritic ulcers in herpetic keratitis with?

Answer 20

STEROIDS!

cause corneal melt

Question 21

is herpetic keratitis painful?

Answer 21

yes - very

Question 22

subepithelial infiltrates are seen in which type of keratitis?

Answer 22

adenoviral keratitis

Question 23

adenoviral keratitis normally follows what?

Answer 23

URTI

Question 24

adenoviral keratitis is contagious and is unilateral

true or false?

Answer 24

false

adenoviral keratitis is contagious and is BILATERAL

Question 25

name the 2 fungi causing keratitis

Answer 25

acanthamoeba and pseudomonas aeruginosa

Question 26

acanthamoeba is classically seen in patients with what?

Answer 26

contact lenses

Question 27

``` painful on eye movements proptosis associated with paranasal sinusitis pyrexial sight threatening ENT CT scan to identify orbital abscesses ``` diagnosis?

Answer 27

orbital cellulitis

Question 28

orbital cellulitis treatment?

Answer 28

broad spectrum antibiotic | abscess requires drainage

Question 29

``` rare red eye sight and life threatening very painful infection inside of the eye ``` diagnosis?

Answer 29

endophthalmitis

Question 30

name the organisms that cause endophthalmitis

Answer 30

commensals - staph epidermidis

Question 31

name the treatment for endophthalmitis

Answer 31

Intravitreal amikacin/ceftazidime/vancomycin and topical antibiotics

Question 32

inflammation of the choroid and retina that is very very very rare diagnosis?

Answer 32

chorioretinitis

Question 33

what 3 things can cause chorioretinitis?

Answer 33

CMV in AIDS toxoplasma gondii toxocara canis (worm)

Question 34

protozoan infection from cats and raw meat mild flu like illness but can cause cysts in immunocompetent patients diagnosis?

Answer 34

toxoplasmosis

Question 35

parasitic nematode - roundworm affects cats and dogs self limiting form granulomas which can cause irreversible visual loss diagnosis?

Answer 35

toxocara

Question 36

how do you diagnose bacterial keratitis?

Answer 36

corneal scrape

Question 37

how do you diagnose endophthalmitis?

Answer 37

aqueous/vitreous for culture

Question 38

how do you diagnose acanthamoeba?

Answer 38

microscopy/culture

Question 39

how do you diagnose toxoplasma and toxocara?

Answer 39

serology

Question 40

how do you diagnose bacterial, chlamydial and viral conjunctivitis?

Answer 40

swab

Question 41

outline the 3 ways that antibiotics work

Answer 41

1. inhibit protein synthesis 2. inhibit cell wall synthesis 3. inhibit nucleic acid synthesis

Question 42

name the most commonly used topical antibiotic

Answer 42

chloramphenicol

Question 43

name the 2 and 1 organisms that chloramphenicol is both bactericidal and becterostatic for respectively

Answer 43

bactericidal - strep and haemophilus bacteriostatic - staph

Question 44

what enzyme does chloramphenicol inhibit?

Answer 44

peptide transferase enzyme

Question 45

what are the 3 side effects of chloramphenicol

Answer 45

allergy irreversibel aplastic anaemia grey baby syndrome

Question 46

name the 2 antibiotics that inhibit cell wall synthesis

Answer 46

penicillins and cephalosporins - have common B lactam ring

Question 47

an infecting lacrimal sac leading to tears collecting and become stagnant and infected is called what?

Answer 47

dacrocystitis

Question 48

name the antibiotic that inhibits nucleic acid synthesis

Answer 48

quinolone - ofloxacin

Question 49

chloramphenicol treats most bacteria except what?

Answer 49

pseudomonas aeruginosa

Question 50

what does fusidic acid treat?

Answer 50

staph. aureus

Question 51

what antibiotic treats gram negative bacteria?

Answer 51

gentamicin

Question 52

name the antiviral that inhibits viral DNA synthesis and is used for dendritic ulcers of the cornea

Answer 52

aciclovir

Question 53

what is topical oxytetracycline used for?

Answer 53

chlamydial conjunctivitis

Question 54

in bacterial keratitis, name the antibiotic that treats most Gram negative bacteria including coliforms, Pseudomonas aeruginosa, Haemophilus influenzae. Not active vs. Strep. pneumoniae

Answer 54

a 4-quinolone such as ofloxacin

Question 55

in bacterial keratitis, name the antibiotic combination that will treat most Gram positive and Gram negative organisms

Answer 55

gentamicina and cefuroxime