Unit 3 - Otitis Externa Flashcards

1
Q

What clinical features are associated with otitis externa?

A

pruritis, pain, foul-smelling odor, and discharge

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

What are the predisposing factors that may lead to otitits externa?

A

Conformation/breed predispositions, behavior of the patient, environment, trauma, obstructive disease, and immunosuppressive diseases

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

What conformation/breed predispositions predispose patients to otitis externa?

A

long, tortuous ear canal, stenotic pinnae, hair in the external ear canal, and thick, dense hair at the opening of the external ear canal

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

What behavior of a patient can predispose them to developing otitis externa?

A

swimming or excessive bathing

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

What environmental conditions can predispose to otitis externa?

A

high environmental temperatures and high relative humidity increase the risk of otitis

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

What does the external canal consist of?

A

skin overlaying cartilage - auricular and annular cartilage

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

What part of the external ear canal does the auricular cartilage make up?

A

the ventral canal

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

What part of the external ear canal does the annular cartilage make up?

A

the horizontal canal

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

True or False: Only certain breeds have hair follicles in their ear canal.

A

False - all breeds have hair follicles in their ear canals, some just have hairier ears

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

When visualising the tympanic membrane, what structures can you see?

A

Pars flaccida, pars tensa, and malleus

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

1

A

pars flaccida

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

2

A

pars tensa

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

3

A

malleus

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

4

A

external ear canal

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

The pars flaccida can change appearance based on ______.

A

pressure

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

What primary factors can induce otitis externa?

A

ectoparasites, foreign bodies, allergies, scaling disorders, autoimmune skin diseases, and juvenile cellulitis

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

What ectoparasites can cause otitis externa?

A

Otodectes cynotis, Otobius megnini, Sarcoptes scabeii, Notoedres cati, Demodex, and Cheyletiella

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

What is the most common primary factor of otitis externa in the dog?

A

atopic dermatitis

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

What are the perpetuating factors for otitis externa?

A

bacteria, yeast, otitis media, erroneous treatment, proliferative/pathological changes of the external ear canal, and polyps

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

What are the most common bacterial isolates in inflamed ears of dogs?

A

Staphylococcus pseudintermedius, Proteus mirabilis, Pseudomonas aeruginosa

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

What are the most common bacterial isolates in inflamed ears of cats?

A

Staphylococcus pseudintermedius and Pasteurella multocida

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

What are some pathological changes that can occur in the ear?

A

inflammation, glandular hyperplasia, epidermal hyperplasia, additional inflammation, fibroplasia, and ossification

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

What is evidence based medicine?

A

conscientious, explicit, and judicious use of current best evidence in making decisions

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

What are ‘best practicies’?

A

Procedures/methods shown by research and experience to produce optimal results that are established or proposed by experts in a field as a standard for use - used to provide clinical practice guidelines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the best practices in the management of otitis?

A
  1. Use appropriate diagnostics
  2. Prepare the canal for treatment
  3. Choose treatment wisely
  4. Medications must be administered properly
  5. Use quality control to evaluate the environment
  6. Consider long-term maintenance therapy
  7. ID and control primary factors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the appropriate diagnostics for diagnosing otitis externa?

A

medical history, PE, otoscopic examination, cytology, culture and sensitivity, and diagnostic imaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the keys/goals of otoscopic examination?

A

examine both canals, visualize the tympanic membrane, and do no harm (may need sedation/anesthesia as necessary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What tools can be used for otoscopic examination?

A

otoscopes, pneumo-otoscopy, and video otoscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the benefits to using a video otoscope?

A

increased magnification over hand held otoscopes, better light and clarity, and they give you the ability to adapt better for individuals visual defecits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the ‘key’ diagnostic test in otology?

A

cytology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

True or False: Cytology should be done in both ears regardless if the disease is unilateral

A

TRUE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How do you perform an ear cytology?

A
  1. Introduce a cotton-tipped applicator gently into the horizontal external ear canal
  2. Roll the cotton swab gently onto a glass slide
  3. Heat fix sample (if greasy)
  4. Stain with Wrights, Diff Quik, or New Methylene Blye
  5. Rinse off the extra stain with water (do this by applying water to the non-stained edge and let it run down the slide until it turns clear)
  6. Air dry, or dry with cool blower
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is normal to find on an ear cytology?

A

keratinocytes, cerumen (ear wax), occasional bacteria (cocci or rods), and occasional yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are you looking for on an ear cytology?

A

Presence of bacteria, including relative nubers, type (rods, cocci), and whether a pure or mixed infection is present

The presence of Malassezia or other fungi, including relative numbers, and if a mixed infection with bacteria

The presence of inflamatory cells: if present, a culture and systemic antimicrobial therapy is indicated

The presence of parasites

The presence fo other atypical cells - like neoplastic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

If examining for ear mites, what should you do with your cytology?

A

Place the sample in mineral oil, cover slip, and then examine without staining under low power magnification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the indications for bacterial culture?

A

known resistant organisms, failure to respond to standard-of-care therapy, previous administration of (several) antibiotics, single population of rods on cytology, and concurrent systemic signs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are the indications for diagnostic imaging of the ear canal?

A

clear loss of tympanic membranes, unable to adequately visualize the TMs, and recurring infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are the options for otic diagnostic imaging?

A

radiography, ultrasonography, MRI, and CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What must you do prior to treatment of otitis externa?

A

treat the perpetuating factors, remove or control primary factors, and minimize predisposing factors of otitis externa

40
Q

When should thorough cleansing of the ear canal be done?

A

after the otoscopic examination and collection of samples for cytology and culture - if indicated

41
Q

What cleansing agents can be used for cleansing of the ear canal?

A

Ceruminolytic agents with or without drying agents

42
Q

Should hair be removed pror to treatment of otitis externa?

A

It is highly recommened because it can prevent proper evaluation, is possibly a predisposing or perpetuating factor, and it blocks penetration of medication into the ear

43
Q

What is the purpose of cleaning the ear canal?

A

Remove debris that causes irritation

Removes debris/hair that blocks movement of medication into horizontal canal

Removes debris that interferes with ‘self-cleansing’

Removes debris that can interfere with activity of active ingredients

Reduces the burden of microorganisms

44
Q

What bacterial otitis externa infections are frequently associated with biofilm production?

A

Pseudomonas (40-90%) and Staphylococcus spp. (30% (otitis) - 96% (various))

45
Q

What are the mechanisms of antimicrobial tolerance with biofilms?

A

antimicrobial depletion - agent doesn’t reach the biofilm

slow penetration - gives cells chance to initiate a stress response

stress response - cells change activity in response to challenge

altered microenvironment - metabolically inactive

persister cells - spore-like cells that can survivie an antimicrobial challenge

46
Q

When is deep ear cleaning/flushing indicated?

A

When you can not clearly see the tympanic membrane

47
Q

What is the goal of deep ear cleaning/flushing?

A

to thoroughly clean the ear

48
Q

What techniques can be used to facilitate deep ear cleaning/flushing?

A

special catheters, teflon-coated catheters, and pump-suction instruments

49
Q

What cleaning agents can be used for deep ear cleaning/flushing?

A

Ceruminolytic agents - squalene, DSS, urea, and carbamine peroxide

50
Q

What cleaning agent is safe for the middle ear?

A

squalene

51
Q

How is a teflon catheter used for deep ear cleaning?

A

Deep general anesthesia is needed, a teflon coated catheter is attached to an IV extension set and then is attached to a 3-way stopcock. The other 2 ports of the stopcock are attached to suction and a 60cc syringe (for saline). The clinician can direct the suction and flushing to specific areas in the ear using this technique

52
Q

Cleaning techniques should be based upon what?

A

history, diagnostic results (organisms present), susceptibility patterns, and locations of infections, and owners abilities, perceptions, finances, etc.

53
Q

What is animax (and similar products) made up of?

A

neomycin, thiostrepton, nystatin, and triamcinolone

54
Q

What are the benefits of using animax?

A

good broad-spectrum action

55
Q

What are the cons to using animax?

A

esthetics and ointment base

56
Q

What is Tresaderm made up of?

A

neomycin, dexmethasone, and thiabendazole

57
Q

What are the benefits of using Tresaderm?

A

Mild antibacterial and yeast, propylene glycol base, and good for first occurance

58
Q

What are the cons to using Tresaderm?

A

Mild activity, must be stored refrigerated/warmed prior to use, and propylene glycol base (toxic effects to ear, can creaste a white substance that looks like pus)

59
Q

What is Otomax/Mometamax made up of?

A

gentamicin, clotrimazole, betamethasone (systemic), mometasone (localized)

60
Q

What are the benefits to using Otomax/Mometamax?

A

excellent ingredients and ointment base

61
Q

What are the cons to using Otomax/Mometamax?

A

ointment base, gentamicin is ototoxic, packaging is terrible (can’t see how much is in bottle)

62
Q

What is Posatex made up of?

A

orbafloxacin, posaconazole, mometasone furoate

63
Q

What are the benefits to using Posatex?

A

broad spectrum, excellent anti-inflammatory, and excellent antifungal

64
Q

What are the cons to using Posatex?

A

ointment base, terrible packaging, and pricing

65
Q

What is Baytril otic made up of?

A

enrofloxacin and silver sulfadiazine

66
Q

What are the benefits to using Baytril otic?

A

excellent activity agains Pseudomonas, broad spectrum, and aqueous base

67
Q

What are the cons to using Baytril otic?

A

minimal anti-fungal activity and no glucocorticoid

68
Q

What is easOtic made out of?

A

gentamicin, miconazole, hydrocortisone aceponate

69
Q

What are the benefits of using easOtic?

A

good ingredients, excellent applicator, excellent anti-inflammatory

70
Q

What are the cons to using easOtic?

A

gentamicin is ototoxic, total volume is insufficient, thicker ointment base, pricing

71
Q

What is Surolan made up of?

A

polymyxin B, sulfates, miconazole, and prednisolone

72
Q

What are the benefits to using Surolan?

A

good activity against Pseudomonas and excellent for Malassezia

73
Q

What are the cons to using Surolan?

A

activity in presence of pus is questionale and is ointment based

74
Q

What commercial otic medications are FDA approved drops?

A

Claro and Osurnia

75
Q

What is Claro made up of?

A

Florfenicol (for gram positive cocci), terbinafine, and mometasone

76
Q

What is Ketocort Otic made up of?

A

Ketoconazole and hydrocortisone

77
Q

What is Osurnia made up of?

A

Florfenicol (for gram positive cocci) , terbinafine, and betamethasone

78
Q

When are residual otic preparations indicated?

A

when clients cannot (or will not) treat daily

79
Q

Aside from commercial otic products, long-acting topical medications, and residual otic preparations, what can be used to treat otitis externa?

A

opthalmologic products, flushes and products labeled for otic use, and compounding (do not try at home)

80
Q

What would be a benefit to using compounding pharmacies?

A

they provide a wide range of active ingredients and a wide range of formulations - there are short half-lives

81
Q

What would be a con to using compounding pharmacies?

A

poor qualitiy control and variability

82
Q

What are the advantages of topical therapy?

A

delivers medication directly to the affected area, high concentrations, and inexpensive

83
Q

What are the disadvantages of topical therapy?

A

Delivery deep into ear may be questionable, owner compliannce, poor penetration if middle ear is involved

84
Q

Is there value to a culture?

A

yes - it informs clinician of organisms that are present, it identifies sensitive antibiotics, and may provide insight ito efficacy of other choices

85
Q

What are the best choices for S. pseudintermedius?

A

Florfenicol, aminoglycosides, fluoroquinolones, and SSD

86
Q

What are the best choices for Pseudomonas spp?

A

aminoglycosides, fluoroquinolones, polymyxin B, SSD

87
Q

What are the best choices for Malassexia?

A

azoles, terbinafine, and nystatin

88
Q

What are the best choices if there is a ruptured tympanic membrane?

A

fluoroquinolones

89
Q

Wjat are the best choices if there are client compliance issues?

A

Claro and Osurnia

90
Q

Choosing wisely is of NO value if?

A

proper application of treatment isn’t facilitated - dose, physical application of the dose, frequency of treatments, and duration of treatment

91
Q

Dosage of medication is dependent on what?

A

the size of the ear canal

92
Q

What is the recommendation for mLs in a dog that is less than 10kg?

A

0.4-0.5 mL

93
Q

What is the recommendation for mLs in a dog that is 10-20 kg?

A

0.5-0.7 mL

94
Q

What is the recommendation for mLs in a dog that is greater than 20kg?

A

1 mL

95
Q

What are the negatives to using mL based on size versus using ‘drops’ that the label says to use?

A

it is a higher cost than using labeled doses and there are possible increased systemic effects