Dermatology Flashcards

(109 cards)

1
Q

What are the key clinical impacts of ectoparasites?

A

Direct impact on host welfare
- esp. parasites causing pruritus & cutaneous myiasis

Predisposition to secondary infections

Vectors of disease

Clinical signs mimic other disease
- e.g. allergic skin disease

Act as pointers to other disease
- E.g. lice may indicate underlying immunocompromise

Zoonotic importance

Economic importance

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2
Q

Give examples of ectoparasites that act as vectors of disease

A

Ticks can transmit:
- babesiosis (cattle/dogs)
- louping ill (sheep/grouse)
- Echinococcus (hydatidosis) (sheep)

Fleas can transmit:
- Dipylidium caninum (dog)
- myxomatosis (rabbit)

Sandflies can transmit:
- leishmaniasis

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3
Q

Give examples of zoonotic ectoparasites

A

Sarcoptes, Cheyletiella, fleas

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4
Q

Give an example of an ectoparasite with significant economic importance

A

Psoroptes ovis (sheep scab)

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5
Q

What are the common clinical signs of ectoparasites on skin surface?

A

Pruritus –> alopecia +- erosions, crust, scale, secondary bacterial infections, chronic changes

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6
Q

Why may fleas not always be found on an animal?

A

Most of their life cycle occurs in the environment

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7
Q

What are common ectoparasites on the skin surface?

A

Fleas
Lice
Surface mites

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8
Q

Which animals are commonly affected by lice?

A

Farm animals, horses, guinea pigs, birds

Incidence greater when animals housed together – seen esp farm animals/horses in winter

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9
Q

How do lice appear on an animal?

A

Approx. 3mm long, visible to naked eye, eggs (‘nits’) attached to hairs

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10
Q

Name surface mites in cattle

A

Chorioptes bovis (common) - tailhead, lower legs, scrotum, udder

Psoroptes (rare)

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11
Q

Name surface mites in sheep

A

Psoroptes ovis - sheep scab

Chorioptes bovis - scrotal mange

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12
Q

Name surface mites in horses

A

Chorioptes equi (common) – leg/tail mange, esp horses with ‘feathers’

Psoroptes spp – body + ear mange

Neotrombicula sp (harvest mite) – head/legs – late summer/autumn

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13
Q

Name surface mites in dogs/cats

A

Otodectes (ear mite) – otitis – dark dry otic exudate

Cheyletiella (fur mite) – truncal scale - zoonotic!

Neotrombicula (harvest mite) – esp head/limbs, late summer/autumn

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14
Q

Name surface mites in rabbits

A

Cheyletiella (fur mite) – (common) truncal scale - zoonotic!

Leporacus gibbus (fur mite) –often asymptomatic, occ –> lesions – brown mite just visible

Psoroptes cuniculi (ear mite) – painful flakey adherent otic crust

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15
Q

Give examples of ectoparasites below the skin surface

A

Burrowing (round) mites
Demodex

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16
Q

What clinical signs do burrowing mites cause?

A

Pruritus, alopecia +- papules, hyperkeratosis, crust

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17
Q

Name a burrowing mite that affects dogs and describe the signs of infestation

A

Sarcoptes scabiei (zoonotic) causes sarcoptic mange, leading to intense pruritus, crusting on pinnal margins, hocks & elbows, along with a positive pinnal-pedal reflex

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18
Q

What burrowing mite affects guinea pigs and is zoonotic?

A

Trixacarus – causes extreme pruritus & can lead to seizures/death

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19
Q

What is a common burrowing mite in birds?

A

Cnemidocoptes (Knemidocoptes) – ‘scaley beak’, ‘scaley leg’

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20
Q

What is Demodex and what clinical signs does it cause?

A

Follicular mite (lives in hair follicles) causing folliculitis, pustules, comedones, alopecia & furunculosis (deep pyoderma)

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21
Q

Which species are most commonly affected by demodicosis?

A

Dogs, hamsters & occasionally cats

Associated with underlying immunocompromise – most common in young/elderly animals

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22
Q

What are the clinical impacts of tick infestations?

A

Can act as disease vectors, cause anaemia with heavy infestations & lead to tick granulomas (if mouthparts retained)

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23
Q

What is cutaneous myiasis, and which animals are most susceptible?

A

Also known as blowfly strike

Infestation with fly larvae (maggots) that feed on host tissue

Sheep & rabbits particularly susceptible, especially in areas with faecal soiling or wounds

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24
Q

How do flea infestations differ in cats and dogs?

A

Dogs: Lesions mainly on caudal/dorsal part of body

Cats: Present with 4 cutaneous reaction patterns (head/neck pruritus, symmetrical alopecia, eosinophilic granuloma complex, or miliary dermatitis)

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25
Which flea species commonly infest rabbits, and where are they found?
Ctenocephalides felis/canis – found on dorsum/rump Spilopsyllus cuniculi – found on pinnae (ears)
26
Which ectoparasite is responsible for ‘sweet itch’ in horses?
Culicoides spp. (midges), causing hypersensitivity reactions Transmit diseases (e.g. bluetongue virus of cattle/sheep)
27
How do Nuisance flies (biting & non-biting) affect animals?
--> irritation --> behavioural changes ---> injury & production loss Transmit diseases (e.g. infectious bovine keratoconjunctivitis (pink eye) or summer mastitis) --> skin disease (e.g. ventral dermatitis or eosinophilic granulomas (horse))
28
What is Dermanyssus gallinae and why is it important?
Poultry red mite Lives in environment & only feeds at night Causes irritation, feather loss & debilitation Zoonotic
29
How do you diagnose ectoparasitic disease?
Consider species, age, husbandry, lesion distribution Determine if parasite is likely on animal or in environment Use appropriate sampling techniques Recognise limitations of diagnostic tests Consider trial treatment in uncertain cases
30
Where do bacterial organisms causing skin disease come from?
Present on normal skin (endogenous infection) - e.g. Coagulase +ve Staphylococci From environment - e.g. Mycobacteria from soil From other animals - e.g. Treponema cuniculi (rabbits)
31
Why does microbial skin disease occur?
Skin's normal protective mechanisms are compromised - Mechanical damage to skin (e.g trauma or ectoparasite) - Immunocompromise - Defects in skin barrier function (e.g. Canine atopic dermatitis or inherent weakness (dogs)) - Changes to skin microclimate (e.g. moisture)
32
Why are dogs predisposed to bacterial skin disease?
Dogs have inherent weaknesses in skin barrier function, including: - Thin stratum corneum - Lack of lipid seal at hair follicle openings - Relatively high skin pH, which favours bacterial growth
33
Which bacterial skin diseases are influenced by changes to skin microclimate?
Dermatophilosis – ‘rain scald’, ‘mud fever’, ‘lumpy wool’ - predisposed by wet skin Pseudomonas infections – thrive in wet environments Intertrigo (skin fold pyoderma) – occurs in dogs due to warm, moist skin folds
34
What is dysbiosis, and how does it relate to bacterial skin disease?
Imbalance in skin microbiome, where normal bacterial diversity is reduced, leading to overgrowth of certain species like Staphylococci & Malassezia
35
Label the portals of entry of microbes
a. Via follicles (bacterial folliculitis) b. Direct entry through damaged skin c. Haematogenous spread (rare)
36
What factors determine the manifestation of bacterial skin disease?
Organism & its virulence factors Predisposing or coexisting conditions The host immune response
37
What are the three main types of inflammatory responses in bacterial skin disease?
Pyogenic – Pus-producing, mainly neutrophils (pyoderma) Granulomatous – Mainly macrophages Necrotising – Involves vascular damage --> ischaemia
38
What is surface pyoderma?
Bacteria multiply on skin surface only
39
Give examples of surface pyodermas in dogs
Canine intertrigo ('skin fold pyoderma’) - mixed microbial overgrowth +/- neutrophilic inflammation Acute moist dermatitis (pyotraumatic dermatitis, 'hotspots’) - acute lesion caused by skin self-trauma Bacterial overgrowth syndrome - bacterial multiplication with no/minimal inflammation - often highly pruritic
40
What is superficial pyoderma and what are the clinical signs?
Infection within epidermis or hair follicles --> papules/pustules --> crust, epidermal collarettes/scale, follicular plugs, alopecia Primarily neutrophilic inflammation
41
Give examples of superficial pyodermas in small animals
Bacterial folliculitis - infection within hair follicle Impetigo - interfollicular (between hair follicles) infection of epidermis Exfoliative superficial pyoderma - infection between layers of stratum corneum (exfoliative toxins --> intraepidermal splitting --> scale)
42
Give examples of superficial pyodermas in large animals
Dermatophilosis – esp horse, cattle, sheep Fleece rot – Pseudomonas - sheep Greasy pig disease (exudative epidermitis) - Staph hyicus
43
What is deep pyoderma and what are the clinical signs?
Infection outside epidermis or hair follicle epithelium due to - rupture of hair follicle wall (furunculosis) - penetrating wounds - haematogenous spread (sepsis) Usually associated with thickening of skin/subcutaneous tissue, nodules, draining sinuses
44
What are examples of deep pyoderma?
Furunculosis (ruptured hair follicles releasing bacteria/keratin into dermis) Abscesses (especially in large animals, cats) Cellulitis (poorly delineated deep infection, may cause tissue necrosis)
45
What is furunculosis, how does it develop, and what are its key features?
Deep pyoderma caused by rupture of hair follicle (extension of folliculitis), releasing keratin & bacteria into dermis ---> pyogranulomatous inflammation (neutrophils + macrophages) Results in thickened skin, nodules, draining sinuses & severe inflammation
46
What is an abscess (deep pyoderma), how does it form, and which animals are commonly affected?
Well-defined accumulation of pus in dermal or subcutaneous tissue, surrounded by fibrous connective tissue Commonly forms due to wounds, foreign bodies, or infections & frequently ruptures & drains spontaneously Common in large animals & cats Wide range of organisms involved, dependent on species & cause of abscessation
47
What is cellulitis (deep pyoderma)?
Poorly-delineated suppurative inflammation of deep subcutaneous connective tissue May lead to skin devitalisation, sloughing & necrosis Various bacteria, including Clostridia, which can produce gas & malodorous infections
48
What causes bacterial granulomatous dermatitis?
Traumatic implantation of saprophytic organisms
49
What are the key examples of bacterial granulomatous dermatitis, and what causes them?
Mycobacterial Granulomas/Pyogranulomas Non-Filamentous Bacterial Granulomas (Botryomycosis) - e.g. Staphylococci, Streptococci, Actinobacillus - Lesions: Small yellow ‘sulphur’ granules Filamentous Bacterial Granulomas - e.g. Nocardia, Actinomyces - Lesions: Nodular masses, may involve bone
50
How can systemic bacterial infections cause skin lesions?
Systemic bacterial infections --> vascular damage in skin --> necrosis e.g. erysipelas in pigs
51
What is a toxin-producing bacterial infection, and how does it affect the skin?
Rare Toxin-producing bacteria trigger severe systemic reaction (similar to toxic shock syndrome) --> fever, shock, organ dysfunction & widespread skin lesions
52
What are the key diagnostic methods for bacterial skin infections?
Cytology - From lesion surface, exudate, FNA - Visualise inflammatory cell type & microorganism - May use special stains (e.g. Ziehl-Neelsen for mycobacteria) Culture - From pustules, exudate, deep tissue biopsy Histopathology - Skin biopsy - +/- special stains (e.g. ZN for mycobacteria)
53
What are the broad principles of bacterial skin disease treatment?
Kill organism - Avoid antibiotics – use topical antibacterials for superficial infections - Use systemic antibiotics for deep infections (based on culture/sensitivity) & abscesses with cellulitis/pyrexia Drainage of abscesses (except in rabbits, where surgical excision is required) Address underlying causes Enhance body's defences
54
What are the three main roles of fungi on the skin?
Commensals (e.g. Malassezia) – normally present, may overgrow Transient contaminants (e.g. saprophytic fungi, some dermatophytes) Active pathogens (e.g. dermatophytes causing ringworm)
55
What are the types of fungal skin disease?
Superficial mycoses – affects outer skin layers Subcutaneous mycoses – deeper skin involvement Deep/systemic mycoses – may spread beyond the skin Hypersensitivity reactions – rare but seen in atopic dogs
56
What are the classifications of dermatophytes?
Geophilic – live in soil, occasional infections Zoophilic – adapted to animals, most common cause of disease Anthropophilic – adapted to humans
57
What is the pathogenesis of dermatophytosis?
Frequent skin contaminants but usually skin defence mechanisms prevent infection. However --> clinical disease if immune system or skin barriers compromised: 1. Skin microtrauma & moisture → inoculation of fungal arthrospores 2. Spores germinate, penetrate stratum corneum & form hyphae 3. Lesions develop within 5-7 days
58
How are dermatophytes transmitted?
They are contagious & transmitted via direct/indirect (fomites) contact Zoonotic
59
What are the common causes of dermatophytosis?
Microsporum spp., Trichophyton spp
60
What are the common clinical features of dermatophytosis?
Common in cows, horses & cats Infection of hair/surface keratin leading to: - folliculitis --> alopecia - adherent scale - erythema, crust, comedones - occasional pustules - variable pruritus Lesions are well-demarcated & often asymmetric
61
What are some uncommon presentations of dermatophytosis?
Furunculosis - Looks similar to deep pyoderma - nodular swelling +/- draining sinus   Fungal kerion - Nodular inflammatory mass due to inoculation of fungus into dermis - Esp. hunting/working dogs   Pseudomycetoma - Esp in Persian cats, Yorkshire Terriers - Subcutaneous/deep mycosis --> nodular granulomas - ulceration & draining tracts with grains   Onychomycosis (claw disease)
62
What are the main diagnostic tests for dermatophytosis?
Microscopy (Direct exam of hair/scales) – look for arthrospores & hyphae Wood’s lamp – detects apple-green fluorescence in Microsporum canis Fungal culture - McKenzie toothbrush technique - Use dermatophyte test medium or Sabouraud’s agar - Daily monitoring required; positive cultures turn red Fungal PCR – highly sensitive & fast, but can't differentiate infection from carriage Skin biopsy – for deep infections
63
What can be visualised using microscopy when diagnosing dermatophytosis?
x4-10 objective - infected hairs look distorted, paler/wider than normal hairs x40 objective - arthrospores around hair +/or hyphae within hair shaft
64
What is the pathogenesis of Malassezia?
1. Commensal yeast normally found in skin & ears 2. Overgrowth due to host factors (e.g. skin folds, other skin diseases, systemic illness) 3. Results in dysbiosis (imbalance in microbiome) 4. Causes clinical disease (not contagious & potentially zoonotic)
65
What is the common presentation of Malassezia in the skin of dogs?
Pruritus Erythema, grease, scale, crust --> chronic changes (lichenification, hyperpigmentation) Often malodourous Focal/multifocal/generalised Diffuse/well-demarcated Commonly affected areas ears, lips, muzzle, interdigital skin, flexor surfaces/medial aspects of limbs, ventral neck/body, axillae, perineum Also paronychia (claw fold infection)
66
What is the common presentation of Malassezia in the ears of dogs?
Pruritus Usually erythro-ceruminous otitis, rarely purulent
67
How does Malassezia infection differ in cats?
Less common than in dogs Pruritus more variable See otitis, chin acne, paronychia or systemic disease
68
How is Malassezia diagnosed?
1. Identify appropriate lesions 2. Identify Malassezia at these sites with cytology - Stained acetate tape strip or stained impression smear - See peanuts using x40-x100 objective 3. If present, assess response to antifungal therapy
69
What are some examples of notifiable viral skin diseases in large animals?
Foot and Mouth Disease Vesicular Stomatitis Swine Vesicular Disease Bluetongue Virus Rinderpest Lumpy skin disease Scrapie Classical Swine Fever, African Swine fever Sheep Pox Goat Pox
70
What happens if a viral notifiable skin disease is diagnosed on a farm?
Usually no treatment Slaughter & disposal of infected & in-contact animals Quarantine/Protection zone Movement restrictions Disinfection +/- Vaccination Eradication programmes Surveillance programmes – monitor spread
71
What are the clinical signs of vesicular (viral) diseases?
Vesicles, erosions, ulcers & crusts Affect muzzle, oral mucosa, tongue, udder, teats, coronary band Can lead to shedding of hooves & horns in severe cases Affect wide range of species, esp. cloven-hooved species
72
Name some notifiable vesicular diseases
Foot and Mouth Disease* Vesicular Stomatitis* Swine Vesicular Disease* Bluetongue Virus* Rinderpest*
73
What is the importance of vesicular diseases?
Many notifiable - often difficult to differentiate from non-notifiable Cause wide economic loss Some zoonotic
74
What are the general characteristics of Papilloma virus skin infections?
Proliferative epitheliotropic lesions (warts) Usually host-specific Enter via microabrasions Usually young animals, regress spontaneously Can undergo malignant transformation to squamous cell carcinomas (rare)
75
Describe Bovine Papilloma Virus (BPV)
Very common in cows (50%) Transmitted by fence posts, halters, contaminated tagging equipment etc. BPVI & II can induce sarcomas/fibrosarcomas Can also cause equine sarcoids
76
Describe the clinical signs of equine papilloma virus
Warts (‘grass warts’) - young horses, self limiting Aural plaques – horses >1yr, persist
77
Describe the clinical signs of canine papilloma virus
Warts - Young dogs, self limiting Pigmented viral plaques - Esp French bulldogs, pugs - Lesions may persist
78
What are the general clinical signs of pox viruses?
Macules, papules, vesicles, pustules, crusts
79
What are some important poxvirus diseases?
Cowpox – Rare in cattle but causes disease in cats (zoonotic, transmitted by rodents) Horse pox, swine pox Sheep pox, goat pox, lumpy skin disease (cattle) - notifiable Myxomatosis (rabbits)
80
What are the clinical signs of Myxomatosis (rabbit pox virus)?
Transmitted by fleas --> oedematous thickened eyelids, lips, genitalia, perineum --> death Occasionally cutaneous form ‘lumpy bunny disease’
81
What are some important parapox viruses?
Contagious pustular dermatitis (Orf) – Oral lesions lambs, teat lesions (mastitis) ewes Pseudocowpox (affects teats) Bovine papular stomatitis (oral/muzzle lesions) All zoonotic!
82
What causes Porcine Dermatitis Nephropathy Syndrome (PDNS), and how does it present?
Caused by circovirus (ubiquitous in pig populations) Results in vasculitis, leading to blotchy (purpuric) skin lesions Can cause subcutaneous microhaemorrhages Must be differentiated from Classical/African Swine Fever (similar skin lesions but more severe systemic effects & notifiable)
83
What virus causes Psittacine Beak and Feather Disease (PBFD)?
Circovirus
84
What is Border Disease, and how does it affect lambs?
Caused by pestivirus Congenital infection results in: - Small, weak, hairy lambs with skeletal muscle tremors (‘Hairy Shakers’) - Can cause abortion & stillbirth
85
How are viral diseases diagnosed?
Often diagnosed clinically Many tests available to verify/identify virus - Detection of virus, viral antigens or nucleic acid - Diagnostic serology - detection of antibodies to virus Diagnostic lab/DEFRA will advice test/sample required
86
What is leishmaniasis (protozoa), and how is it transmitted?
Vector-borne disease caused by Leishmania spp., transmitted by sandflies Causes wide range of skin & systemic signs - Long incubation (years), slowly progressive Can control but no cure
87
What animals are commonly affected by leishmaniasis?
Dogs >> Cats Zoonotic, seen in dogs imported from endemic areas (e.g. Mediterranean, Portugal)
88
How is leishmaniasis diagnosed?
Aspirates (lymph node, bone marrow) Serology/PCR Skin biopsy (detects organisms inside macrophages)
89
What are the most common causes of dermatological disease?
Metabolic Neoplastic Inflammatory Immune mediated Infectious Traumatic
90
In order to treat a dermatological disease effectively what needs to be established first?
What is happening to the skin? Why is this occurring? - Often secondary to underlying cause
91
What do we need to investigate in the history of the dermatology patient?
92
Give examples of how sex can influence dermatological disease
Entire male dogs – endocrine skin changes from testicular neoplasia Post-whelping bitches – may develop temporary generalised alopecia
93
Give examples of how breed can influence dermatological disease
Welsh ponies – Culicoides hypersensitivity Feathered horses – Chorioptes mange Persian cats, Yorkshire Terriers – Dermatophytosis Shar Pei, Bulldogs, Labradors – Atopic dermatitis Staffordshire Bull Terriers, Bulldogs – Demodicosis
94
Give examples of how lifestyle can influence dermatological disease
Housed/stabled animals – more lice, dermatophytosis, Chorioptes mange Outdoor grazing (dawn/dusk) – more Culicoides hypersensitivity Overcrowding – increases facial dermatitis in sheep Hunting terriers/cats – higher risk of Trichophyton dermatophytes, cowpox
95
Give examples of how general health can influence dermatological disease
Underlying relevant systemic disease - e.g. In hyperadrenocorticism (cause of alopecia) owners will usually report marked polydipsia & polyphagia Underlying comorbidity - e.g. concurrent cardiac failure --> sedation is riskier & some treatments not appropriate Drug history - cutaneous drug reaction? - iatrogenic effects?
96
What do we need to investigate in the clinical examination of the dermatology patient?
97
What are the key history questions in dermatology?
Age of onset? Pruritus – Is it primary (itch that rashes) or secondary (rash that itches)? Lesion type & distribution – symmetrical, localised, generalised? Progression? – acute vs. chronic Contagion – risk to other animals/humans Response to previous treatment – owner recall bias can be issue
98
How does the age of onset influence the diagnosis of dermatological disease?
Young/Immature Animals - Diseases linked to immunological immaturity: Demodicosis, dermatophytosis, viral papillomas - Congenital defects Young Adults - Prone to environmental atopy (dogs, cats, horses) - Immune-mediated diseases Older Adults - Endocrinopathies (e.g. hypothyroidism, hyperadrenocorticism in dogs) - Systemic disease & neoplasia
99
Why is it important to do a general clinical examination?
Signs of systemic disease may - Underlie dermatological disease - Affect diagnostic approach - Affect treatment of skin
100
What are the key steps in performing a dermatological examination?
Ensure adequate restraint & good lighting (e.g. pen torch) Be systematic – don't just examine areas noticed by owners Check hard-to-access areas: - Under the tail, inguinal region - Mucocutaneous junctions - All feet, including undersides - Ears Feel & smell the coat Look beneath hair for hidden lesions Record findings accurately - area affected, lesion (descriptors, size, distribution), use diagrams
101
Why are first lesions crucial in dermatological diagnosis?
Primary lesions provide key diagnostic clues before secondary changes occur E.g. Demodicosis may present initially with non-pruritic alopecia & comedones Misdiagnosis or inappropriate treatment (e.g. steroids for pruritus) can worsen condition Identifying first lesions helps avoid progression & inappropriate treatment choices
102
What are the 5 major presenting signs of dermatological disease and why are they important to identify?
Pruritus Alopecia Crusting Scale Nodules /ulceration Allows standardised approach to be used as basis for case. Overlapping signs can be confusing – always ask what happened 1st
103
What are the key in-house tests used in dermatology?
Coat brushing – for ectoparasites, scale Skin scrapes – deep (Demodex), superficial (Sarcoptes, Cheyletiella) Skin cytology – bacteria, yeast (Malassezia) Dermatophyte culture Trichogram (hair pluck) Wood’s lamp
104
What laboratory tests may be needed for dermatology cases?
Haematology & biochemistry Endocrine testing Bacterial culture & sensitivity Fungal PCR Biopsy & histopathology
105
What test procedures might be done in dermatology?
Parasite treatment trials Food elimination trials Changes in housing or activities
106
How do secondary bacterial and yeast infections impact dermatological disease?
Common Increase disease severity & pruritus Alter lesion appearance, making diagnosis harder Change nature of pruritus Require treatment (cytology-guided) to resolve primary disease effectively
107
What is the importance of accurate diagnosis in dermatology?
Ensures a good outcome Avoids unnecessary use of drugs Entirely possible in house for most dermatological problems Symptomatic treatment (esp. pruritus) often --> owner frustration, cost & adverse effects of chronic therapy
108
3yo FN Labrador presents to you with lesions on ventrum, as pictured. Dog has developed these lesions over past week, but they haven't been seen before. However she has suffered from low-grade pruritus of ventrum, face & feet for past 12 months, & ventral pruritus has increased in past 1-2 weeks. In-contact dogs/people are fine & her general health is good All dogs are treated every 4w with sarolaner/milbemycin tablets There is no contact with other animals or change of environment What is your ranked differential diagnosis list? What initial investigations would you propose to progress your diagnosis?
109
2yo Scottish Blackface ewe in December, farmer is concerned about skin problem he has just noticed. Ewe is one of group of 30 that are currently housed. Similar lesions found today on few others in group. Believed to be pruritic, though farmer is bit unsure. Farmer recently developed red patch of skin on her hand. The sheep are well otherwise. What is your ranked differential diagnosis list? What initial investigations would you propose to progress your diagnosis?