Brainscape's Knowledge GenomeTM

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


See full index

SS - Exam 3 > Ocular Infections I > Flashcards

Ocular Infections I Flashcards

1
Q

Extraocular tissues

A

Eyelids - blepharitis
Conjunctiva - conjunctivitis
Cornea - keratitis
Nasolacrimal system - dacryocytitis

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

Intra ocular tissues

A

Uvea = uveitis
Iris & ciliary body = anterior uveitis
Choroid = posterior uveitis
Retina = retinitis
Optic nerve = optic neuritis

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

Microorganisms inside/around eye

A

• Conjunctiva few bacteria has low numbers of bacteria
Cornea has very few bactiera
Intraocular tissues are sterile
• Normal flora & transient
• Mostly Intraocular tissues are Gram +
• Fungi are transitory

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

Organisms in eye

A

Conjunctival Sac
Predominantly Gram +
• Staphylococci
• Streptococci
• Corynebacterium
Occasional Gram –
• Neisseria
• Moraxella
Fungi
• Rare & transitory

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

Defense of the eye

A

Normal flora of conjunctiva
Tears / blinking

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

Normal flora of conjunctiva

A

Present in low numbers
Primarily gram positive bacteria e.g., Staphylococci, Streptococci, Cornynebacterium
Fungi only there transitorily

important role in colonization resistance
use of antibiotics may disrupt this defense mechanism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Tears and blinking

A

Rinse” the ocular surface
Contain antibacterial substances
e.g., IgA, lysozyme, and lactoferrin

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

Predisposing factors for extra ocular infections

A

Most extraocular infections are secondary
They need some breach in ocular defenses to allow
disease to occur:

Trauma - Breaks in epithelial barrier of cornea, conjunctiva, ultraviolet radiation
Infections in adjacent structures - Ears, lip folds, mouth
Drying of the cornea - Keratoconjunctivitis sicca
Immunosuppression - Local or systemic
Co-infection with other agents - Viruses and bacteria; local or systemic infections

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

Predisposing factors for Intraocular infections

A

Most intra infections are secondary
Often manifest as systemic infections/disease
Immunosupporession most common factor

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

Routes of entry for extra ocular infection

A

direct inoculation
Overgrowth of normal flora in nearby sites - pseudo intermedius*
Inoculation of exogenous bacteria - P. Aeruginosa
Inoculation of viruses or recrudescence of existing infection - herpes

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

Routes of entry for Intraocular infections

A

Most common route is systemic infections**
Eyes are target organs for systemic infections
Access via uveal or vascular tracts
Typically infectious agents or immune complexes become established in uvea - chorioretinitis and anterior uveitis

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

Direct inoculation for Intraocular infections

A

Local injury - trauma
Less common, usually unilateral

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

Mechanism of pathogen damage

A

Adhere
Invade tissues
Evade host defense mechanisms
Cause host cell damage

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

Bacteria organisms that cause infection in all species eyes

A

Staphylococcus & Streptococcus spp*
Trueperella & Corynebacterium spp
Pseudomonas aeruginosa**
Coliforms (E. coli, Klebsiella, Proteus)
Chlamydia spp*

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

Bacteria organisms causing eye infections in dogs

A

Brucella canis
Ehrlichia canis*
Rickettsia rickettsia*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Bactiera for eye infections in cats

A

Chlamydia felis*
Mycoplasma felis*

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

Bacteria for eye infections for dogs & horses

A

Borrelia burgdoferi*
Leptospira*

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

Bacteria for eye infections for cattle (sheep/goat)

A

Moraxella bovis** ü
Listeria monocytogenes ü
Histophilus somni* ü
Moraxella ovis ü
Mycoplasma conjunctivae* ü
Mycoplasma bovoculi

19
Q

Bacteria for rabbit eye infections

A

Pasturella multiocida

20
Q

Bacteria for bird eye infections

A

Mycoplasma gallisepticum

21
Q

Viruses for cat eye infections

A

Feline herpes 1**
Feline corona virus/FIP *
FLeV
FIV
FPLeV

22
Q

Viruses for dog eye infections

A

Canine distemper virus**
Canine adenovirus*
Canine herpes virus

23
Q

Viruses for equine eye infections

A

Equine herpes virus 1&2
Equine viral arteritis virus

24
Q

Viruses for cattle eye infections

A

Bovine herpes virus
BVDV
MCF

25
Q

Fungi for dog eye infection s

A

Blastomyces
Histoplasma
Prototheca

26
Q

Fungi for cat eye infection s

A

Cryptococcus

27
Q

Diagnosing eye infections

A

Often a presumptive diagnosis based on history/signs
Definitive diagnosis is made in <50% of cases
Infections can by polymicrobial

28
Q

Steps for diagnosing ocular infections

A

Thorough ocular exams
Sample collection
Cytology/culture/susceptibility testing
Other - PCR, serology, virus isolation, mycoplasma culture

29
Q

Types of sample collections

A

Swab /cytobrush- conjunctiva/cornea
Kimura spatula - conjunctiva /cornea
Aqueous centesis

30
Q

Blepharitis

A

inflammation of eyelids
Bacteria, fungi, parasites can all cause this. Can occur alone or with other ocular diseases

31
Q

clinical signs of blepharitis

A

Eyelid swelling
Erythema
Skin ulceration
Pruritus
Ocular discharge

32
Q

Bacteria that is most common for causing blepharitis

A

Gram positive cocci - S. Pseudintermedius, B haemolytic, strep, - canis/zooepidemicus
Fungi (dermatophytes)
Parasites (Demodex, sarcoptes, Cuterebra larvae)

33
Q

Chlamydia felis

A

Causes conjunctivitis and keratoconjunctivitis in young cats - infected by carrier animals
DX is commonly presumptive or doing a conjunctival smear

34
Q

Snuffles

A

Upper respiratory tract in rabbits caused by pasturellosis can also cause conjunctivitis / eye leaking
Pasturella multocida

35
Q

Keratitis - causing bacteria

A

Gram positive cocci - S. pseudintermedius, ß-hemolytic
Streptococci e.g., S. canis, S . zooepidemicus)

36
Q

Diagnosing equine keratitis - eye exam

A

Examining eye - nerve blocking is common
Looking for foreign body, perform fluoroscein test to determine presence of ulcer

37
Q

Diagnosing equine keratitis work up

A

Corneal scraping for cytology / culture
Culture the scraping - expect low numbers of bacteria in normal flora on cornea

38
Q

4 pt rule for normal flora

A

It is part of normal flora at this site.
It is present in increased numbers.
It CAN cause the disease observed?

39
Q

2 rule with normal flora

A

Is it NOT part of normal flora at site
It CAN cause disease observed

40
Q

Pseudomonas keratitis

A

Direct inoculation from a saphrophyte
Bacterial pili attach/grow on damaged cornea
Multiply & invade into corneal stroma = produce exotoxins
Exotoxins kill corneal epithelial cells = keratin w exudate

41
Q

P. Aeruginosa keratitis

A

Causes “melting” ulcers
Due to other exotoxins and enzymes released from lyses inflammatory cells
Can cause rapid iris prolapse and globe collapse

42
Q

DX pseudomonas keratitis

A

Cytology / culture
Susceptibility testing - not predictably susceptible w lots of intrinsic Antimicrobials resistance

43
Q

Treating pseudomonas keratitis

A

Treat empirically immediately waiting for culture
“Melting” is an emergency
Sub palpebral lavage system - easy treatment
Antibiotics 4-6x a day
Atropine to dilate the pupil, pain relief
NSAID - flunixin
Acetyl cysteine - anti collagenase, activate against exotoxic effects

SS - Exam 3 (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions