Chapter 19 - eyelids, claws, anal sacs and ears Flashcards
Are glands of Zeis prominent sebaceous glands or modified sweat glands?
Prominent sebaceous glands
Are glands of Moll prominent sebaceous glands or modified sweat glands?
Modified sweat glands
What is another name for Meibomian glands?
Tarsal glands
Which deep mycoses is most likely to affect the eyelids in cats?
Histoplasma capsulatum
Which oral drug can be used to treat FHV-1 associated blepharitis?
Famciclovir
Which drugs can trigger drug-induced apoptosis in allergic blepharitis?
Potentiated sulphonamides
Penicllins
Cephalosporins
Bilateral ulcerative blepharitis affecting the medial canthi is seen in which breeds of dog?
GSDs
Longhaired Dachs
Toy/minature Poodles
Name two metabolic/nutritional causes of blepharitis?
Zinc-responsive dermatosis
Generic dog food dermatosis
Superficial necrolytic dermatitis
Which breeds of cat are affected by idiopathic blepharitis (‘dirty face’)?
Persians
Himalayans
Periocular vitiligo occurs most commonly in which breed of dog?
Rottweilers
Transient periocular leukotrichia, associated with pregnancy or systemic illness, is seen in which breeds of cat?
Siamese
What is the most common canine eyelid tumour?
Sebaceous adenoma (from Meibomian glands)
What is the most common feline eyelid tumour?
Squamous cell carcinoma
What is a chalazion?
A painless swelling of the Meibomian gland caused by a blockage of its duct and retention of secretions. It looks like a firm, white-yellow nodule.
Leukonychia, when seen in isolation, is suggestive of which disease?
Vitiligo
Which immune-mediated disease, other than SLO, can be localised to the nails?
Lupus erythematosus
Subepidermal bullous dermatoses
Pemphigus vulgaris
Which breeds are predisposed to SLO?
GSDs
Gordon Setters
Are intracellular bacteria a normal or abnormal finding in canine anal sacs?
Normal
What is the most common type of anal sac neoplasia?
Adenocarcinoma
What is the most common endocrine cause of otitis?
Hypothyroidism
Which disease causes tightly adhered hyperkeratotic crusts (gold coloured) on erythematous plaques on the pinnae in cats?
Feline proliferative and necrotising otitis externa
Calcification of connective tissue occurs inside or outside the auricular cartilage?
Outside
Potent surfactants and detergents are often found in what type of ear cleaner?
Ceruminolytic
Which ceruminolytic agent was shown not to cause proliferative middle ear disease?
Squalene
How does EDTA make antibiotics/antiseptics more effective?
Induces changes in cell membrane permeability
Name two ‘soft’ glucocorticoids
Hydrocortisone aceponate
Mometasone furoate
Cystadenomatosis is most common in what signalment of cat?
Males, older age
Abyssinian, Himalayan and Persian and DSH
Is cystadenomatosis associated with viral infection in cats?
No - does not appear to be associated with papillomavirus, feline infectious peritonitis, feline immunodeficiency virus/feline leukemia virus status or other identifiable illnesses.
Cystadenomatosis has been found to primarily affect the preauricular region, concave pinna, concha, tragus and antitragus, and the external ear canal of cats; which non-aural areas can be affected?
Periocular, perioral and perianal regions
Which glands are affected in cystadenomatosis and where are they found?
Modified sweat apocrine glands
- found in the skin surrounding the eyelid margins (Moll’s glands), lip margins and perianal regions, but are most prevalent in and around the ears
What is cerumen made of?
- Fatty secretions from sebaceous and ceruminous glands - triglycerides, sterol esters, fatty acid esters and squalene
- IgG> IgA, IgM
- Squames
Which part of the ear canal contains more ceruminal than sebaceous glands?
Ceruminous glands are more prevalent in the horizontal meatus compared with the vertical meatus, where there are more sebaceous and apocrine glands
Why are the lesions of cystadenomatosis blue/grey in colour?
- Distension of skin
- Pigmentary contributions from hemosiderin and ceroid of the thick acellular or cell-poor fluid filling the cystic lumen
What % of isolates of Pseudomonas aeruginosa from canine OE are MDR?
Up to 92%
Which cytokine is overexpressed in dogs with atopic otitis and otodectic mange and correlates with the otitis severity in atopic dogs?
IL-8
Significant increases in the levels of IL-10 were also overexpressed in atopic otitis but at lower rates
What effect did cleaning with an ethoxydiglycol, capric glycerides, isopropyl alcohol,calendula, tromethamine, glycerin and lipacids cleaner (Sonotix®) have on erythemato-ceruminous OE in dogs with predominantly Malassezia overgrowth?
- It reduced pruritus score, OTIS-3, cytology score and otic secretion score in 7 days and further reduced it in 14 days
- IL-8 also reduced compared to baseline and there was a decrease in free lipids and an increase in bound lipids.
Based on PCR, which three bacteria were most abundant in healthy ears of dogs?
Cutibacterium acnes (previously known as Propionibacterium acnes),Staphylococcus pseudintermedius, and Streptococcus spp
In dogs with OE, 78.3% had microbial overgrowth on PCR testing; was bacterial or fungal overgrowth more common?
- 62.78% bacterial overgrowth
- 8.5% fungal overgrowth
- 7.0% had both
What type of bacteria is Finegoldia magna?
Gram +ve anaerobic coccus
Found in healthy ears of dogs on PCR but much more abundant in OE
Oclacitinib has been shown to be effective at managing ear tip ulcerative dermatitis; which differential diagnoses should be ruled out before starting treatment?
Infectious cases - leishmaniosis, bartonellosis (Bartonella henselae), Rickettsia rickettsia
What % of myringotomy aspirates can be contaminated by material from the external ear canal and how can this be reduced?
68%
By performing a ventral approach (special table etc. needed)
What are the benefits of CO2 laser surgery of proliferative ear canal/pinnal lesions compared to traditional surgery?
- Ability to sculpt rather than just excise
- Sterilisation of the wound bed
- Ablates sensory nerve endings, helping to reduce postoperative pain
Which special stain has been shown to identify biofilm?
PAS - stains polysaccheride matrix
When staining otic discharge with PAS, which findings are suggestive of biofilm associated infection?
- Presence of three or more microbial aggregates
- Presence of high-density material
- Extracellular staining and the presence of discretely stained matrix
What are the gold standard techniques to identify biofilm?
- Confocal laser scanning microscopy (CLSM) or scanning electron microscopy (SEM)
- Fluorescence in-situ hybridisation (FISH)
What are the benefits of referral for cases of chronic OE?
- Number of episodes of otitis was reduced
- Median time between recurrence of otitis reduced
- Proliferative pathological change was significantly reduced
- Better outcome if referral occurred within 6 months
- Have equipment to perform effective, deep cleaning of the external ear canal
- Access to advanced imaging modalities
- Colleagues in associated fields such as neurology and soft tissue surgery, for specialist input
What is the pattern of epithelial migration on the tympanic membrane?
Centrifugal
Which ear treatment has been shown to exhibit the fastest diffusion through the cerumen lipids?
Aurizon
How long are compounded solutions of dexamethasone (0.1 and 0.25 mg/ml) in ear cleaner stable for?
At least 90 days at room temperature
- Except if using ULTRA+KETO Flush (0.15% ketoconazole, TrizEDTA)
Kaimio et al. (2021); which factors were associated with ceruminal gland hyperplasia in American cocker spaniels?
Bacterial growth in microbiological culture of aural exudate
- Previous history of OE, cutaneous findings or underlying allergies were not
True or false; It is normal for the feline ear to have a moderate amount of dark brown ceruminous debris present in the canal
True
What is considered normal on cytology of cat ears?
- 2 or fewer Malassezia PHPF
2. 4 or fewer bacteria PHPF
Among cats presenting to general practice in a UK study, what % had OE?
2.8%
What are the signs of sebaceous gland dysplasia?
- Occurs congenitally in short-haired kittens (4–12 weeks old)
- Hypotrichosis starts on the head but quickly generalizes
- Bilateral crusting within the canal and along pinnal margins
- Generalized alopecia and scale with a coarse haircoat
- Otitis may occur secondary to obstruction of the canal
Otodectes cynotis is associated with what % of feline OE cases?
53–69%
What % of cats may have signs of Otodectes outside the ear canal?
Up to 23%
Has been associated with chin acne
Apart from Malassezia, which other fungi can affect the ear canal of cats?
Dermatophytes
Cryptococcus neoformans
Aspergillus fumigatus
Sporothrix schneckii
Idiopathic facial dermatitis of Persian and Himalayan cats can cause OE in ~50% of cases; which treatments are effective?
Ciclosporin, topical tacrolimus
Describe the lesions of proliferative and necrotising OE in cats (PNOE)
- affects the concave pinna and ear canal
- can also affect eyelids or be generalised
- proliferative plaques that develop thick, adherent, tan to dark brown layers of keratinaceous exudate
- erosions or ulcers develop over time due to friable proliferative tissue
- pain and pruritus
What age of cat is typically affected with PNOE and what treatment is effective?
- Young: kittens or young adults
- Topical tacrolimus and topical and systemic glucocorticoids
- Ciclosporin?
OE has been reported in what % of cats with PF?
7-30%
How often do inflammatory aural polyps recur after traction, per-endoscopic trans-tympanic traction and curettage and VBO?
Traction = up to 67% (reduced if given steroids)
Per-endoscopic trans-tympanic traction and curettage = 13.5%
VBO = 5%
What are the most common aural neoplasias in the cat?
Ceruminal gland adenocarcinoma > SCC > carcinoma of unknown origin
Name the two most common rod shaped bacteria from cats with OE
Pseudomonas aeruginosa
Pasteurella multocida
Other than Staph. spp, Pseudomonas aeruginosa and Pasteurella multocida, which other bacteria are associated with OE in cats?
Streptococcus canis, Escherichia coli, Mycoplasma, Klebsiella and Corynebacterium
O’Neill et al. (2021); what were the predisposing factors for OE in dogs in UK PCP?
Pendulous and v-shape ear carriage
Breed: Basset Hound, Chinese Shar Pei, Labradoodle, Beagle and Golden Retriever at highest risk
O’Neill et al. (2021); which dog breeds were at lower odds of OE in UK PCP?
Chihuahua, Border Collie, Yorkshire Terrier and Jack Russell Terrier
Do silver nano-particles (AgNPs) have an antibiofilm affect?
Yes - in vitro
S. pseudintermedius exposed to 20 μg/ml of AgNPs formed less bacterial slime compared to the controls on CRA plates. Scanning electron micrographs showed that the biofilm had few individually scattered cells along its surface when treated with AgNP concentrations of 20 and 10 μg/ml. Untreated surfaces showed an aggregated biofilm.
Leonard et al. (2021); does topical mometasone affect ear microbiota and mycobiota in dogs with AD?
No
What are the most common causes of vestibular disease in dogs?
- Idiopathic
- Otitis media/interna
- Meningoencephalitis of unknown origin (MUO)
- Brain neoplasia
- Ischaemic infarct
- Hypothyroidism
What age of dog is more likely to have OM/OI as a cause of vestibular disease than idiopathic / MUO / infarct?
Young dogs are more likely to have OM/OI
Older dogs are more likely to have idiopathic / MUO / infarct
What autologous product can be used to manage canine aural haematomas?
Leukocyte- and platelet-rich plasma (L-PRP)
- can accelerate the healing process by providing increased concentrations of platelet-derived growth factors
- resolved haematomas in 12/15 dogs after 0.5-1ml instilled following drainage
Which diluent has the most stable concentration of ceftazidime when refrigerated for 28 days?
Sodium chloride
Triz EDTA and Douxo Micellar Solution were less stable compounded solutions
O’Neill et al. (2021); which risk factors were identified for aural haematoma in dogs?
- V-shape or semi-erect pinnae
- OE was present in 54.6%
- Breed:
Bull Terrier
SBT
Saint Bernard
French Bulldog
Golden retriever
What were the clinical signs associated with patulous Eustachian tube in the dog?
OE characterized by frothy liquid and food fragments in the ear canal in addition to sneezing after drinking water
Continuous vacuum drainage for surgical treatment of aural haematoma in dogs is performed on which side of the pinna?
Convex side of the pinna
Where does the cleft occur in aural haematoma?
Within the cartilage
How is the microbiota and mycobiota affected in dogs with OE?
- Staphylococcus was the most abundant taxa across all groups.
- Ears cytologically positive for cocci had decreased diversity
- All types of OE were associated with decreased fungal diversity compared to controls
LED-illuminated gel consists of two components: a light source comprised of blue light emitting diodes (LEDs; peak wavelength between 440 and 460 nm) and a topical substrate containing chromophores. Was once or twice weekly application more effective at treating OE in dogs?
Twice weekly
Which clinical signs can be associated with middle ear effusion in dogs?
Head and neck pain, impaired hearing, facial paralysis, vestibular signs, head tilt, and otic pruritus.
Middle ear effusion is most common in which breeds?
CKCS
Brachycephalic breeds e.g. Boxer, bulldogs
Milne et al. (2020); what were the findings from middle ear effusion in dogs?
- Neutrophils and macrophages predominate
- 79% showed no bacterial growth on culture
- 38% had neuro deficits
- 56% had AD and OE
- Staph. pseud was the most common bacterial isolated 67%
- Bulla mucosa was thickened (dilated glands were present in unaffected dogs as well)
Tyler et al. (2020); what % of cats had Malassezia on ear cytology and which factor was it associated with?
37.8%
Associated with increasing age
Which phyla of bacteria are most abundant in the cerumen of healthy dogs?
Proteobacteria Actinobacteria Firmicutes (includes Staph) Bacteroidetes Fusobacteria
What are microRNAs?
MicroRNAs (miRNAs) are short (∼22 nucleotides), single-stranded non-coding RNAs that modulate gene expression by binding to complementary target mRNA
Micro(mi)RNAs involved in monocyte/macrophage polarization were detected in cerumen of dogs with OE, what does this suggest?
That during inflammatory responses, monocytes are attracted to cerumen, and become activated on site and modulated by miRNAs
Can miRNAs discriminate otitis-affected from healthy dogs?
Yes - miR-125b and miR-320a
- with high sensitivity (>86%) and specificity (>97%), may be suitable biomarkers
Can chlorhexidine-Tris-ethylenediaminetetraacetic acid (EDTA) and medical grade honey solutions be used to treat OE with Malassezia overgrowth in dogs?
Yes - both reduced clinical signs and cytological counts of MP
Which novel topical treatments have shown in vitro efficacy against Gram -ve bacteria associated with OE in dogs?
- Narasin (ionophore) with Tris-EDTA or disodium EDTA
2. Manuka oil with Tris-EDTA
What are the risk factors for facial nerve paralysis in dogs?
- Male
- Middle age
- CKCS
What were the most common diagnoses for dogs with facial nerve paralysis in Chan et al. (2020)?
- Idiopathic (37% of naturally occurring FNP)
- Surgical trauma
- Neuromuscular disease
- Intracranial disease
- OM/OI (14.3% of naturally occurring FNP)
- Hypothyroidism (3-4% of cases)
- Non-surgical trauma
Which is the most sensitive method for diagnosing otoacariasis?
Otoscopy alone sens = 67%
Curette sampling sens = 93%
Swabbing sens = 57%
Otoscopy and curettage = 100%
Otoscopy and swabbing = 86%
What % of dogs with chronic OE (> 2m) have OM with no overt clinical signs?
21%
Is the MIC for silver sulfadiazine lower than the concentration of the commercial product for Pseudomonas aeruginosa?
Yes - 1% product
MIC 1-64 ug/ml
Cole et al. (2019); are bacteria commonly cultured from middle ears of CKCS with OME?
No - 10% of external canals, 25% of middle ears and 8% from both
- Coagulase-negative staphylococci and Staphylococcus pseudintermedius most common
Is MRI or CT more sensitive at diagnosing early tympanokeratoma?
MRI
Which adjuvants are effective in vitro against common bacteria and Malassezia associated with OE in dogs?
N-acetylcysteine
Tris-EDTA
Disodium EDTA
Which medium and time-frame are preferable for assessing biofilm production of Pseudomonas aeruginosa isolates?
Mueller–Hinton Broth and 24 hr incubation
What % of clinical isolates of Pseudomonas aeruginosa from OE in dogs can produce biofilm?
> 90%
May et al. (2019); was NAC synergistic, indifferent or antagonistic when used with enrofloxacin and gentamicin in vitro against Staphylococcus pseudintermedius, Pseudomonas aeruginosa and Corynebacterium?
Indifferent to antagonistic
Name the anatomy
What is the diameter of the auditory tube and which cells line it?
≤ 1.5 mm
Pseudostratified ciliated columnar epithelium and goblet cells
Belmudes et al. (2018); what % of dogs with and without OE had bulla abnormalities on CT?
- 40.7% of dogs with OE >6 months
- OM associated with purulent or proliferative OE (particularly severe OM in French bulldogs)
- 14.2% of dogs with peripheral vestibular signs but no OE
- 9/9 CKCS with deafness showed fluid filled bullae
Imai et al. (2018); what % of dogs with tympanokeratoma had bulla expansion?
53.8%
What are the three theories of tympanokeratoma formation in dogs?
- Migration of cells through damaged tympanic membrane
- Invagination of tympanic membrane into middle ear
- Auditory tube dysfunction - Metaplastic change of ciliated epithelium within middle ear
- Chronic inflammation
Which method and outcomes were reported with non-surgical management of tympanokeratoma in dogs?
- Endoscopic removal of material via ear canal
- Manually and with diode laser - Ongoing post-operative lavage and at home cleaning – labour intensive
- Recurrence of clinical signs in 4/13 ears (30.8%)
- Procedure repeated once in one dog and twice in another
- Facial nerve paralysis developed in 1/11 dogs post-operatively
Swales et al. (2018); medical management of OM in cats is successful in what % of cases?
72.7%
What are the complication rates for VBO for polyps in cats?
- Lower risk of recurrence reported cf. traction (0-8%)
- Immediate post-op Horner’s (57-83%)
- Otitis interna/vestibular signs (26-42%)
- Facial nerve paralysis (12-13.5%)
Post-operative complications usually reversible
Describe the per-endocscopic approach to polyp removal in cats and the rate of complications
- Traction to debulk followed by endoscopic removal of any residual portion of polyp using curettage
- Septum bullae removed to improve access if necessary
Resolution of clinical signs in 35/37 cats (94%) over 19-month follow up
- 8% developed Horner’s syndrome
- 13.5% had polyp recurrence
One method of collecting ear cytological specimens utilizes a cotton-tipped swab inserted into the vertical ear canal. A proposed alternative method is to aspirate exudate from the deep horizontal canal using a rubber tube. Is there a difference in cytological assessment with these methods?
More neutrophils are obtained with the tube method otherwise no significant difference
What are the most common causes of Pseudomonas OE in dogs?
Allergy»_space;> masses and endocrine disease > autoimmune disease
How were brainstem auditory evoked responses affected in dogs treated with aqueous solutions of marbofloxacin, gentamicin, tobramycin and ticarcillin?
Brainstem auditory evoked responses in dogs treated with aqueous solutions of marbofloxacin or gentamicin remained unchanged or improved after therapy of otitis media but were impaired in dogs treated with ticarcillin or tobramycin
How is tympanic bulla anatomy affected in brachycephalic dogs?
- CKCS had significantly flatter tympanic bullae (greater width:height ratios) versus Pugs, English bulldogs, Labrador retrievers, and JRTs.
- French Bulldogs and Pugs had significantly more overlap between tympanic bullae and temporomandibular joints
- All brachycephalic breeds had significantly lower tympanic bulla volume:weight ratios
- Soft tissue attenuating material (middle ear effusion) was present in the middle ear of 48/100 (48%) of brachycephalic breeds
In a 2017 study, which antiseptics/cleaners were most effective in vitro against M. pachydermatis? Otoclean EpiOtic MalAcetic 1.5% hydrogen peroxide
Hydrogen peroxide 1.5% > Epiotic® and MalAcetic® > Otoclean®
What are the risk factors/primary causes of Aspergillus OE in dogs and cats?
- Typically seen as unilateral otitis externa in cats and larger breed dogs
- Possible risk factors include immunosuppression and otic foreign bodies
- Previous antibiotic usage was common
Rim enhancement of polyps on post-contrast CT is present in what % of cases and associated with what pathology?
73%
Positively correlated with the histologic grade of inflammation in the superficial stroma
How often are ear cleaners contaminated and which bacteria are involved?
- 10% of the bottle tips and in 2% of the solutions.
- Isolated bacteria included Staphylococcus pseudintermedius, Bacillus spp., coagulase-negative Staphylococcus spp., Micrococcus spp. and Burkholderia cepacia
- The contamination rate was significantly higher when Tris–EDTA was an ingredient.
Are Corynebacterium considered pathogenic when isolated from canine OE?
- May be pathogenic
- However, almost invariably present with other microbes and usually disappear from the ear with resolution of other infections
- Gentamicin and enrofloxacin would be rational choices for the empirical, topical therapy
Krainer et al. (2021); what % of French bulldogs with no history of otitis had middle ear effusions on CT and did this correlate with nasopharyngeal dimensions?
54%
Not related to nasopharyngeal dimensions
Has fluorescence light energy (FLE) been used to treat canine perianal fistulae?
Yes - small number of dogs - significant reduction in vocalization, straining and licking after 2 weeks and lesional areas had significantly decreased after 5 weeks
How effective is pip/taz at treating bacterial OE in dogs?
- 84.6%) of dogs had clinical and microscopic resolution after28 days of treatment - rest partial response
- 38.5% developed acute or progressive Malassezia otomycosis during or following treatment.
Has Tris-NAC been shown to have anti-biofilm affects?
Yes - for Pseudomonas and Staph. pseud (not for Malassezia!)
