Chapter 12 - Congenital/Hereditary Flashcards
(158 cards)
1
Q
Name two breeds in which primary seborrhoea is most commonly recognised
A
American Cocker
English Springer
WHWT
Basset Hound
2
Q
What is the epidermal renewal time in seborrheic Cockers?
A
8 days (21 = normal)
3
Q
Which anatomical sites show the most severe signs with primary seborrhoea?
A
Periocular, perioral, pinnae, intertiginous areas of feet, axillae and groin
4
Q
Which breeds show a dry, flaky phenotype of seborrhoea?
A
Irish Setters and Dobermans
5
Q
With the greasy phenotype of seborrhoea, which anatomical sites show dry, flaky skin?
A
Caudodorsum
6
Q
Shampoos containing which products are suitable for more severe flaky scaling?
A
Sulfur and salicylic acid
7
Q
Which condition can occur with long term use of retinoids?
A
KCS
8
Q
Calcitrol therapy can decrease which hormone level?
A
Parathyroid hormone
9
Q
What effect do steroids have on dogs with greasy seborrhoea?
A
Atrophic effect on the epidermis and sebaceous glands
10
Q
Primary seborrhoea has been recognised in which breeds of cat?
A
Persian
Himalayan
Exotic short hair
11
Q
What is the epidermal renewal time with ichthyosis?
A
3.6 days
12
Q
In golden retrievers, which epidermal structure is abnormally retained with ichthyosis?
A
Corneodesmosomes
13
Q
Which keratin is reduced in the epidermis of Norfolk terriers with ichthyosis?
A
Keratin 10
14
Q
Which breed of dog may not show signs of ichthyosis at birth?
A
Golden retrievers
15
Q
Which breed of dog can develop blisters and erosions with mild skin trauma with ichthyosis?
A
Norfolk Terriers
16
Q
With ichthyosis, is the hyperkeratosis ortho- or para-keratotic?
A
Orthokeratotic
17
Q
How long can it take to see a response to retinoid treatment of ichthyosis?
A
Up to 6 months
18
Q
What is the difference in clinical distribution of signs between ichthyosis and follicular parakeratosis?
A
Nasal planum and footpads are not affected in follicular parakeratosis and there is minimal involvement of glabrous skin
19
Q
What abnormality is seen on histopathology of follicular parakeratosis?
A
Lipid vacuoles in the debris and keratinocytes in the follicular epidermis
Orthokeratotis basket-weave hyperkeratosis
20
Q
Epidermal dysplasia in WHWT is associated with which microbe?
A
Malassezia
21
Q
Which anatomical site is affected in schnauzer comedo syndrome and which type of schnauzer is affected?
A
Dorsum
Miniature
22
Q
What are the 3 categories of the inherited form of epidermolysis bullosa?
A
Epidermolysis bullosa simplex
Junctional epidermolysis bullosa
Dystrophic epidermolysis bullosa
23
Q
Where do clefts form with epidermolysis bullosa simplex?
A
Basal layer of the epidermis
24
Q
Where do clefts form with junctional epidermolysis bullosa?
A
Lamina lucida of basement membrane zone
25
Where do clefts form with dystrophic epidermolysis bullosa?
Below the lamina densa
26
Name two breeds of dog, bar collies and shelties, affected by familial dermatomyositis
```
Beauceron shepherd
Belgian Tervurens
Portugese water dogs
Corgi
Lakeland terrier
Chow
GSD
Kuvasz
```
27
Define anychoschizia
Splitting of nails
28
What are the cutaneous histopathology findings in dermatomyositis?
Scattered hydropic degeneration of the surface and follicular basal cells with occasional apoptosis of basel cells +/- intrabasal or subepidermal clefts
29
Darrier disease in English setters is associated with abnormal homeostasis of which mineral?
Calcium (due to depletion of SERCA2-gated stores)
Also reported in an Irish Terrier
30
Define trichoptilosis
Longitudinal splitting of the distal end of the hair
31
Medullary trichomalacia typically affects which breed?
GSDs
32
Which hairs are affected in shaft disorder of Abyssinian cats?
Whiskers and primary hairs
33
Which hairless dog breeds have ectodermal dysplasia?
Mexican hairless and Chinese crested
34
In black hair follicle dysplasia, by what age does near total alopecia occur?
6-9 months (starts from 4 weeks)
35
What distribution of pattern baldness in dachshunds is more common in females than males?
Pre- and post-auricular, ventral neck, ventrum and caudomedial thighs
36
Where does the genetic mutation occur in colour dilution alopecia?
MLPH (melanophilin) gene (SNP/insertion)
Same gene is affected in black hair follicle dysplasia!
37
What are the late stage follicular changes in colour dilution alopecia?
Dilated, cystic follicles
38
Which breed is typically affected by follicular lipidosis?
Rottweiler
39
What presenting sign of follicular lipidosis is pathognomic?
Hair loss restricted to the mahogany points of the face and feet
40
Axillary hyperpigmentation, lichenification and alopecia is seen with which disorder?
Acanthosis nigricans
41
Which breed is affected by acanthosis nigricans?
Dachshund
42
In which breeds/species have cases of Chediak-Higashi syndrome been reported?
```
Persian cats
White tigers
Hereford cattle
Aleution mink
Humans
```
43
Chediak-Higashi syndrome is associated with which coat colour in Persians?
Blue-smoke with yellow eyes
44
What are the clinical signs of Chediak-Higashi syndrome?
Increased susceptibility to infection, partial oculocutaneous albinism, photophobia, bleeding disorders and large eosinophilic granules in neutrophils and macrophages on blood smears (lysosomes)
45
Canine cyclic haematopoiesis is associated with a mutation of which gene?
APB3
46
Acquired aurotrichia occurs in which breed of dog?
Min. Schnauzers
47
What are the clinical signs and course of aurotrichia?
Gold coloured hair on the dorsum (+/- periocular skin and ears) that spontaneously resolves in 6-24 months
48
In cutaneous aesthenia, collagen forms which shape instead of normal cylindrical fibrils?
Twisted ribbons
49
In cutaneous aesthenia, decreased activity of procollagen peptidase leads to lack of cleavage of what from type 1 procollagen?
N-terminal propeptides
50
In cutaneous aesthenia, how is wound healing affected?
It can be normal but leaves thin, white scars.
51
In cutaneous aesthenia, what is the extensibility index in affected dogs and cats?
14.5% dogs
| 19% cats
52
In cutaneous aesthenia, which supplement can be beneficial in dogs?
Vitamin C
53
Multiple collagenous nevi are a marker for which systemic disease?
Renal cystadenocarcinomas or uterine leiomyomas
54
Acrodermatitis is reported in which breed of dog?
Bull terriers
55
In acrodermatitis, what is there defective metabolism of?
Zinc and copper
56
The Millon reaction stains tyrosine which colour?
Orange
57
Which cat breeds are reported with urticaria pigmentosa?
Sphynx
Himalayan
Devon Rex
Siamese
58
Urticaria pigmentosa is a hyperplasia of which inflammatory cell?
Mast cells
59
A mutation in which gene is associated with ichthyosis in Golden Retrievers?
```
PNPLA1 - (insertion-deletion)
AND
ABHD5 (deletion)
```
60
A mutation in which gene is associated with ichthyosis in American bulldogs?
NIPAL4 (ICHTHYN) - deletion
61
A mutation in which gene is associated with ichthyosis in Jack Russell Terriers?
Transglutaminase 1 (TGM1) - insertion
62
A congenital and familial form of keratoconjunctivitis sicca and a roughened/curly hair coat with scaling, abdominal hyperpigmentation, foot pad hyperkeratosis and nail dystrophy has been recognised in which breed of dog?
Where is the gene mutation?
CKCS
FAM83H (deletion)
63
Which gene is mutated in nasal parakeratosis of Labrador retrievers and Greyhounds?
SUV39H2 (deletion)
64
Footpad hyperkeratosis in Irish terriers and Kromfohrlander is associated with a mutation of which gene?
FAM83G (missense)
Also reported in Bedlington terriers!
65
Junctional epidermolysis bullosa in the German pointer and Australian shepherd is associated with which respective mutations of which genes?
LAMA3 - German pointer (insertion)
| LAMB3 - Australian shepherd (missense)
66
A mutation in the COL7A1 gene in Bassets, central Asian shepherd and Golden retrievers is associated with which type of epidermolysis bullosa?
Dystrophic epidermolysis bullosa (complex rearrangement, SNP in GR)
67
PKP1 gene mutation in Chesapeake Bay retrievers is associated with which disease?
Ectodermal dysplasia/skin fragility syndrome
| SNP, splicing
68
What are the clinical signs of Darrier disease?
Exophytic, irregular and alopecic plaques
69
Lamellar ichthyosis in Great Danes is associated with a mutation in which gene?
SLC27A4 (FATP4) - SNP
Codes for fatty acid transport protein 4
70
Which is more acidic, the upper or lower stratrum corneum?
The pH decreases as you move up the layers of the stratum corneum
71
Is calcium higher or lower in the upper stratrum corneum?
Calcium levels decrease as you move up the layers of the stratum corneum
72
True or false; free amino acids provide some UV protection
True
73
Which corneodesmosomes remain in place the longest, those at the surface/face or the edges of the corneocytes?
Edges
Leads to the basket weave pattern seen on histopathology
74
Which structures are affected in ectodermal dysplasia?
- hair follicles and cutaneous glands are absent or fewer in number than normal
- in the hairy regions, there are no secondary hairs
- hypodontia or oligodontia; teeth are conical and misaligned
- reduced number/function of tracheobronchial glands and the lacrimal and meibomian glands
75
What are the clinical signs in X-linked hypohidrotic ectodermal dysplasia in dogs?
- symmetrical alopecia or hypotrichosis from birth affecting frontotemporoparietal area, sacral region, ventral region of the neck and trunk, and proximal halves of the 4 limbs
- dry, less shiny coat (reduced/loss of sebaceous glands)
76
How does x-linked hypohidrotic ectodermal dysplasia (deletion mutation of the EDA gene) differ from ectodermal dysplasia in Mexican hairless dogs?
Mexican and Peruvian hairless dogs and Chinese crested dogs are characterized by missing hair and teeth, a phenotype termed canine ectodermal dysplasia (CED). Mutation analysis revealed a frameshift mutation within the FOXI3 coding sequence in hairless dogs; this is an autosomal semi-dominant trait.
77
A mutation in which gene is associated with EBS in Eurasier dogs?
PLEC (SNP, nonsense)
78
In dogs, are EBS/JEB/DEB autosomal recessive in inheritance?
Yes
79
A mutation in GDNF is associated with which disease in dogs?
Acral mutilation syndrome (SNP) - hunting/working breeds
80
A mutation in MKLN1 is associated with which disease in dogs?
Lethal acrodermatitis in Bull terriers (SNP)
81
A mutation in ATP2A2 is associated with which disease in dogs?
Gene encoding calcium pumps
Darier disease in Irish terriers (SINE) - autosomal dominant!
82
A mutation in FGF3/FGF4/FGF19 is associated with which disease in dogs?
Dermoid cysts - Rhodesian and Thai ridgebacks (duplication)
83
A mutation in MYO5A is associated with which disease in dogs?
Dilute colour coat with neurological defects in Dachshunds (insertion)
84
What type of mutation is present in FOXI3 gene in ectodermal dysplasia of Chinese crested/Mexican and Peruvian hairless dogs?
Insertion
85
Labrador and DSH, Bengal cats have a mutation in COL5A1 associated with which disease and mode of inheritance?
Ehler's-Danlos syndrome
| Autosomal dominant
86
A mutation in ADAMTS2 is associated with which disease in dogs?
EDS type VII, dermatosparaxis in Dobermans
| (SNP missense) - AR
87
Renal cystadenocarcinoma and dermatofibrosis in GSD is associated with which gene mutation and mode of inheritance?
FLCN (SNP, missense)
| AD
88
A mutation in UNC93B1 is associated with which disease in dogs?
ECLE in GSHP and Vizslas
| (SNP, missense) - AR
89
HAS2 mutations in Shar-Peis are associated with hyaluronanosis; what is the type of mutation and mode of inheritance?
Duplication
| Autosomal semi-dominant
90
A mutation in SGK3 is associated with which disease in dogs?
Hypotrichosis in Scottish deerhounds and American hairless terrier - AR
91
Which gene mutation is associated with hairlessness in Sphynx and Birman cats?
```
KRT71 = Sphynx
FOXN1 = Birman (short life expectancy!)
```
92
Musladin-Lueke syndrome in Beagles is associated with which gene mutation?
ADAMTSL2
| (SNP, missense) - AR
93
In Dobermans, which gene mutation can increase the risk of melanocytic neoplasia?
SLC45A2 (deletion) - AR
| Oculocutaneous albinism
94
If you suspect a genodermatosis, how do you interpret a negative targeted genetic test?
- . Inconclusive - it is possible that an independent mutation event, perhaps in the same gene, has happened
- Targeted tests interrogate only a single position in the genome, they do not comprehensively test an entire gene or the entire genome
- Use WGS
95
Which type of blood sample should you take for genetic analysis?
EDTA
96
Female dogs with heterozygous NSDHL loss-of- function variants develop verrucous epidermal keratinocytic nevi that follow Blashko’s lines. What does the NSDHL gene encode?
1. NAD(P) dependent steroid dehydrogenase-like = an enzyme required for cholesterol synthesis
2. The pattern is due to random X-chromosome inactivation in females
97
Cholesterol biosynthesis is blocked in affected areas with NSDHL loss-of-function mutations leading to build up of toxic metabolites, what topical treatment may be beneficial?
Topical therapy containing cholesterol and lovostatin to prevent the further production of toxic metabolites
98
What are the clinical signs of Darier disease in dogs?
- Hyperplastic, crusted lesions
- Alopecic, scaly, crusted plaques
- Young (~6m)
- Pressure points, pinnae
99
What do you see on histopathology of Darier disease in dogs?
Epidermal hyperplasia, follicular and epidermal hyperkeratosis as well as suprabasal and intraepidermal acantholytic cleft formation
100
Darier disease has been reported in Irish terriers (ATP2A2 mutation) and which other breed?
```
English setter (mutation not identified)
Doberman
```
101
A mutation in KRT5 is associated with which disease in cattle?
EBS Friesian-Jersey cattle
| (SNP) - AD
102
Name five breeds of dog, other than Rhodesian ridgeback, that have been reported with dermoid cysts?
```
English bulldog
Dalmatian
Dachshund
Cane Corso
Chinese crested dog
Swedish vallhunds
Frenchie
Saint Bernard
Boxer
Shih Tzu
Chow
Boerboel
Yorkshire terrier
English springer
Brittany spaniel
Bull terrier
Siberian husky
Great Pyrenees
```
103
What is a dermoid cyst?
A congenital malformation that results from the incomplete separation of the skin from the neural tube during embryonic development
104
What does a dermoid cyst look like?
- Typically has an orifice in the skin over the dorsal midline that is continuous with a sinus tract towards the underlying tissues at various depth
- The lumen is often filled with sebum, keratin debris and hair, and may become inflamed or infected, forming a draining tract through the skin
105
Have dermoid cysts been reported in cats?
Yes - rarely (Burmese > others)
106
Follicular hyperkeratosis has been reported in which breeds of dog?
Rottweiler, Siberian husky, Labradors
107
What is the presumed mode of inheritance of follicular hyperkeratosis in dogs?
X-linked as all cases have been reported in females
108
How do the clinical signs of follicular hyperkeratosis differ from ichthyosis?
1. The skin of the nasal planum and footpads is not affected and there is minimal involvement of glabrous skin.
2. Hairs are often clumped together in a brown-yellow waxy material. Comedones are numerous.
3. Dogs are often stunted (as are their littermates) and they may have non-cutaneous congenital defects.
109
NIPAL-4 encodes which protein that is expressed in the granular layer?
Ichthyin
1. It functions as a magnesium transporter, which delivers this cation, a required co-factor for the CoA synthetase that acylates very long chain fatty acids, some of which are incorporated into the acylceramides that comprise the lipid monolayer of the CLE
2. In ichthyin-deficient ARCI, there is evidence of toxic metabolite accumulation in the cytosol of granular layer keratinocytes
110
What is missing in the image on the right (white arrows)?
Cornified envelope
111
Which breeds of cat are affected by idiopathic facial dermatitis?
Persians and Himalayans
112
Which breed of cat is affected by ulcerative nasal dermatitis and what is the age of onset?
Bengal
| 4-12 months
113
What is the difference in the pathology of EBS in dogs and buffalo compared to cattle?
- Dogs and buffalo – suprabasal separation occurs without cytolysis of basal cells
- Cattle - basal separation occurs with cytolysis of basal cells (cytolytic)
114
When are clinical signs apparent with EBS?
First week of life
115
What age do cattle and dogs typically live to with EBS?
Cattle – 1-4 weeks
| Dogs 1-4 years
116
Which species develop oral ulceration with EBS?
Dogs
Cattle
Buffalo
Dogs and cattle
| Buffalo do not develop oral ulceration with EBS
117
What do you see on histopathology with EBS?
1. Subepidermal separation with a minimal neutrophilic inflammation.
2. Extensive areas of intact full thickness epidermis are separated from the dermis, forming large clefts containing eosinophilic fluid, extravasated erythrocytes and occasional neutrophils
118
Enamel hypoplasia is a common finding in humans with JEB, has it been reported in animals?
Sporadically in horses and dogs
119
Scar formation occurs with healing of DEB lesions in which species and why?
- People and goats
| - Occurs because blisters below the lamina densa will lead to a mesenchymal wound-healing response in the dermis.
120
Histopathological findings in the skin and oral mucosa of DEB are similar to those found in EBS and JEB; however, periodic acid Schiff staining of histological sections demonstrates what difference?
BM is attached to the roof of the cleft
121
Which type of epidermolysis bullosa is the most clinically severe?
JEB
122
Frattini et al. (2021); what % of GSHP are carriers of LAMA3 mutation for JEB?
12.9%
123
Frattini et al. (2021); what coat colour was associated with the LAMA3 mutation?
Solid coat colour
124
Apart from GSDs, which breed has focal metatarsal fistulation been reported in?
Weimaraner
125
In a recent case report of familial vasculopathy, which breed of dog was affected? Clinical signs were erosive and ulcerative lesions affecting nasal planum.
Scottish terrier
Treated with CsA and prednisolone
126
Mucopolysacharidosis is is seen in which breeds of cat?
Siamese (and crosses)
127
What are the clinical signs of ulcerative nasal dermatitis of Bengal cats?
1. Dry and scaly nose
2. Becomes hyperkeratotic, crusted and fissured
3. Depigmentation may occur
128
How do you treat ulcerative nasal dermatitis of Bengal cats?
- oral prednisolone
| - topical salicylic acid / moisturisers / steroids / tacrolimus
129
At what age do signs of psoriasiform lichenoid dermatosis begin in springer spaniels?
4-18 months
130
What are the clinical signs of psoriasiform lichenoid dermatosis in springer spaniels?
- Asymptomatic, symmetrical, erythematous lichenoid papules and plaques
- Pinnae, external ear canal, inguinal
- Become hyperkeratotic and spread to the face, ventrum and perianal skin
- Possible Staph. trigger
- Can be CsA induced in other breeds!
131
What do you see on histopathology of psoriasiform lichenoid dermatosis in springer spaniels?
- Superficial perivascular to interstitial dermatitis
- Psoriasiform epidermal hyperplasia
- Lichenoid dermatitis
- Intraepidermal micro-abscesses (neutrophils and eosinophils)
- Chronic lesions show papillated epidermal hyperplasia and papillomatosis
132
Which treatment has been associated with resolution of psoriasiform lichenoid dermatosis in springer spaniels?
Cefalexin
133
What are the cutaneous clinical signs of dermatomyositis?
- Signs appear before 6m old and severity peaks at 12 m
- Areas of mechanical trauma
- Periocular, muzzle, ear tips, carpi, tarsi, digits, tail tip
- Onychorexis/-schizia/-madesis
- Alopecia, erythema, scaling, mild crusting, rarely vesicles, ulceration
134
When does myositis appear in dermatomyositis?
Months after skin lesion develop
| - correlates with skin lesion severity
135
What are differentials for dermatomyositis?
```
Demodicosis
Staph. folliculitis
Dermatophytosis
DLE
EBS (if vesicles present)
```
136
What are the treatment options for ischaemic dermatopathies in dogs?
1. Pentoxifylline (25 mg/kg BID)
2. Vitamin E (200-800 IU/d)
3. Omega-3 supplements
4. Prednisolone 1mg/kg/d
5. Tetracycline/nicotinamide
6. Topical tacrolimus 0.1%
137
What is the name of this hair shaft abnormality?
Trichoptilosis
138
What is the hair shaft abnormality?
Medullary tricomalacia
139
Before hair loss, how does the coat change with medullary trichomalacia?
1. Hairs loose flexibility and stand away from the coat
2. Hairs appear thicker than normal and stiff to touch
3. Hairs break easily
140
Can inflammation result in localised, acquired, pili torti?
Yes
141
What is this hair shaft abnormality?
Pili torti
142
What is this finding indicative of?
Shaft disorder of Abyssinian cats
| Onion shaped swelling at the hair tip
143
Spiculosis in Kerry Blue terriers typically affects which signalment and which body sites?
Young intact males
| Most common over lateral hock
144
Name four breeds of dog affected by black hair follicle dysplasia
```
Bearded and Border collies
Basset hound
Papillon
Saluki
Beagle
JRT
American cocker
Schiperke
CKCS
Dachshund
Gordon setter
Munsterlander
Pointer
```
145
What is the first sign of black hair follicle dysplasia?
Lack of luster of black hairs
146
What are the four syndromes of pattern baldness in dogs?
1. Pinnal alopecia of Dachshunds
2. American water spaniels; ventral/lateral neck, trunk, rump, posterior thighs
3. Greyhounds; caudal thighs
4. Pre- and postauricular; Dachshunds, Boston terriers, Chihuahua, whippet, Manchester terrier, greyhounds, Italian greyhounds
147
What abnormalities are found in greyhounds with bald thigh syndrome?
1. Transverse fractures, central longitudinal splitting and other structural defects in the proximal parts of the hair shafts associated with a downregulation of genes and proteins essential for hair shaft formation
2. Possible defect in IGFBP5
148
Name five breeds of dog affected by non-colour linked follicular dysplasia
1. Siberian husky and Alaskan malamute (guard hairs on trunk lost, coat turns red)
2. Doberman, miniature pinschers and Manchester terriers (flank and dorsum)
3. Airedale, Boxer, English bulldog, SBT, wirehaired griffons and affenpinschers (flank/saddle)
4. Irish water spaniels, Portugese water dogs, curly coated retrievers (caudal dorsum and trunk)
5. Weimaraner (trunk)
149
Melanoderma and alopecia is a hereditary disease in which breed of dog?
Yorkshire terrier
Symmetrical marked alopecia and hyperpigmentation on the dorsal nose, pinnae, tail and feet
150
Backel et al. (2019); which breeds of dog were over-represented with ischaemic dermatopathy?
```
Toy and miniature poodles
Chihuahuas
Maltese
Yorkshire terriers
Jack Russell terriers
```
151
Backel et al. (2019); what % of ischaemic dermatopathy cases were associated with vaccination?
48.3%
| Younger age and higher body weight positively correlated with greater likelihood of vaccination
152
Backel et al. (2019); what correlated with poor outcome in cases of ischaemic dermatopathy?
Body weight <10 kg and older age
153
What are the five categories of ischaemic dermatopathy?
1. Canine familial dermatomyositis (FDM)
2. Juvenile onset dermato-myositis-like disease in atypical breeds
3. Post-rabies vaccine panniculitis
4. Generalized vaccine-associated
5. Generalized idiopathic
154
What are the clinical signs of ischaemic dermatopathy?
- Alopecia
- Hyper- or hypopigmentation
- Scaling
- Crusts
- Ulcers
155
At which body sites are clinical signs apparent in ischaemic dermatopathy?
- Lesions are found most commonly at vaccine sites and/or pinnal margin, tip of the tail, head, face and pressure points.
- An acral distribution also is frequently observed and characterized by lesions on phalanges, paw pads and claws(onychodystrophy and onychomadesis)
156
What are the histopath findings in ischaemic dermatopathy?
1. Follicular atrophy
2. Cell-poor lymphocytic interface dermatitis
3. Dermal oedema/mucin deposition
4. Eosinophilic tinctorial changes to the dermal collagen and vascular tunics imparting a “smudged” appearance
157
Dermal arteritis of the nasal philtrum is reported in dogs of which signalment?
```
Middle age (5 years)
Saint Bernards, giant schnauzer, basset hound, blood hound, great Dane, GSHP
```
158
What is the preferred topical treatment for dermal arteritis of the nasal philtrum in dogs?
Tacrolimus 0.1%
