Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OD2 - Applied Clinical Training & Research Studies in Vision and Optometry > MIIM - Bacteria and Fungi Causing Ocular Infections V - Week 3 > Flashcards

MIIM - Bacteria and Fungi Causing Ocular Infections V - Week 3 Flashcards

1
Q

Describe the gram stain, shape, and metabolic state of pseudomonas. Does it produce spores? What are its growth requirements?

A

It is a gram negative rod
Aerobic
Minimal growth requirements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What two pigments are produced by pseudomonas?

A

Pyocyanin

Fluorescein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What bacteria is the most common cause of contact lens associated keratitis.

A

Pseudomonas aureginosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Following eye injury, what bacteria is a common cause of exogenous endophthalmitis?

A

Pseudomonas aureginosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Are the outcomes of pseudomonas eye infections good or poor?

A

Poor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name 7 means of pathogenesis for pseudomonas.

A 
Adhesion structures, especially good for CL, CL cases
Nutritionally resourceful - ubiquitous
Opportunistic
Induces inflammatory response
Produces exotoxins
Pyocyanin targets many pathways
Has cytotoxic and invasive strains
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name 4 places where pseudomonas could form a biofilm.

A

CL, CL cases, pipes, and showerheads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Name two specimens that can be used in a suspected pseudomonas infection.

A

Conjunctival swab

Corneal scraping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do cultures of pseudomonas look and smell like?

A

Large colonies which produce blue-green water soluble pigment
Has a distinct sweet ammonia smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Is pseudomonas oxidase positive or negative?

A

Positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What media does pseudomonas grow on?

A

Basal media like NA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Is pseudomonas aureginosa inherently resistant or susceptible to most antibiotics?

A

Is resistant to many commonly used antibiotics, and can acquire resistance to others.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What should be done prior to treating pseudomonas with antibiotics?

A

Susceptibility test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Name 4 ways pseudomonas infections can be prevented.

A

Preventing CL associated infections by improving cleaning and wearing compliance
Discourage home-made cleaning salines
Using approved and sterile cleansers to remove biofilms
Using sterile CL storage solutions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name 5 ocular diseases that can be caused by pseudomonas.

A 
Keratitis
Keratoconjunctivitis
Orbital cellulitis
Endophthalmitis
Uveitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How can orbital cellulitis cause a thrombosis, and is this serious?

A

If the infection spreads through thin bone, the abcess can pass into the blood stream.
Is life threatening.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Does orbital cellulitis cause proptosis?

A

It may

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name 4 agents that can cause orbital cellulitis.

A

Streptococcus pneumoneae
Haemophilus influenzae type b
Staphylococcus aureus
Streptococcus pyogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the most common cause of orbital cellulitis?

A

Sinus infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define endophthalmitis.

A

Inflammation of the interior of the eye (inside the globe).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the typical cause of endophthalmitis?

A

Eye surgery or trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Is endophthalmitis a minor condition or an emergency?

A

Emergency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Name 5 symptoms of endophthalmitis.

A

Progressive vision loss, photophobia, eye pain, red/pink eye, floaters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Name an endogenous source of endophthalmitis. Are these cases common or rare?

A

Haematogenous spread from a distant source like endocarditis.
These are rare.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Name 3 ways of managing an edophthalmitis infection.
Intravitreal injection of antibiotics - repeated if no response -systemic antibiotics should be used if the source is endogenous Vitrectomy in severe cases
26
Can vision be retained or restored in endophthalmitis cases?
If appropriate care is given, useful vision can be recovered. In severe cases, it may result in the loss of sight or the eye.
27
Describe the gram stain, shape and metabolic type of bacillus bacteria. Do they produce spores? Where are they found?
They are large gram positive rods Produce spores Aerobic or facultative anaerobes Found in soil and dust
28
Are bacillus bacteria easily cultured in labs?
Yes
29
What is bacillus cereus, and what disease is it commonly associated with?
A opportunistic pathogen associated with exogenous endophthalmitis
30
What is the gram stain, shape, and metabolic type of clostridia? Do they produce spores?
Large gram positive rods Produce spores Obligate anaerobes
31
Where are clostridia found (3)?
Soil, dust, and the GIT of warm-blooded animals (including humans)
32
What two diseases can clostridia cause?
Keratitis and exogenous endophthalmitis
33
Name three species of clostridia, and a disease associated with each.
C. tetani - tetanus C. botulinum - botulism C. perfringens - gas gangrene/food poisoning
34
Describe the gram stain ,shape, and metabolic type of enterobacteriaceae.
Gram negative rods | Facultative anaerobes
35
Name 4 enterobacteriaceae associated with ocular disease. Describe which are normal microbiota, and which arent.
Environmental (associated with water) -Serratia Normal microbiota - Proteus - E. coli - Klebsiella
36
In what two ways are enterobacteriaceae associated with ocular disease?
Contact lens associated infections | Penetrating eye injuries
37
Are enterobacteriaceae resistant or susceptible to antimicrobials?
Can be very resistant
38
How can enterobacteriaceae infections be managed (1) and prevented (1)?
Due to resistance, antibiotic susceptibity testing is essential Prevention of CL infections by improving wearing and cleaning compliance
39
What kind of stain, metabolic type, and shape are mycobacteria?
Acid fast stain needed Large rods Aerobic
40
Name the two major mycobacteria, and the disease they cause.
M. tuberculosis - tuberculosis | M. leprae - leprosy
41
Do mycobacteria grow fast or slowly? Describe why.
Slow growing due to restricted entry of nutrients through its waxy cell wall
42
Do tuberculosis or leprosy infect the eye as part of a systemic infection?
Yes
43
Name two mycobacteria species that cause keratitis? What other disease can they cause?
M. chelonae M. fortuitum They can also cause endophthalmitis
44
What disease can mycobacteria rarely cause?
Scleritis
45
Name two means of managing mycobacteria infection.
Susceptibility testing for antibiotics | Surgery for patients who dont respond
46
What kind of sterol can be found in the cell membrane of fungi?
Ergosterol
47
In what two ways do fungi propagate?
Vegetatively or by spores
48
What are the two classifications of fungi (3)?
Yeast - unicellular Moulds - filamentous Some can be both - dimorphic
49
Define saprophytic.
Gain energy from the breakdown of dead organic matter
50
Can fungi infect eyes with an intact epithelium?
Rarely - they are opportunistic
51
Are fungal eye infections common? What is the most common disease?
They are rare. | Keratitis is the most common
52
How do fungi cause corneal damage?
Injury by tree branches
53
What fungal infection do CL wear predispose one to?
Oculomycoses
54
What fungi is involved with causing fungal endophthalmitis in hospitalised patients?
Candida sp.
55
Name 4 common fungi for ocular infections and their classification.
Yeast -Candida (especially albicans) Filamentous - Fusarium - Aspergillus - Scedosporium
56
Name 4 means of pathogenesis for fungal infectious agents.
Adhesins Pseudohyphae in some species Fungal toxins Inducing inflammation
57
Can candida albicans be found in healthy individuals?
Yes, in 50% of healthy people it is found on most mucous membranes
58
What is the ideal specimen for a suspected fungal infection?
Discharge swab, corneal scrapings
59
What can be expected in a microscope image of a suspected fungal infection (4)?
Direct examination of pus, corneal scrapings may show yeast/hyphae/spores.
60
On what media do fungi grow, yeast and others?
HBA for yeasts or SAB for others.
61
What is the management for a fungal infection? Name a problem with treating fungal infections.
Long term antifungal chemotherapy. | Difficult to achieve selective toxicity.
62
What do antifungals often target?
The cell membrane of fungi.

OD2 - Applied Clinical Training & Research Studies in Vision and Optometry (174 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions