Dermatology

Name 3 acquired traumatic alopetic diseases

Physical assault Chemical assault Pruritic assault

Name 5 hereditary alopetic skin diseases

Canine primary sebhorrea,

Hereditary hypotrichosis, Follicular dysplasia, Colour dilution alopecia/black hair follicular dysplasia, Pattern alopecia,

Recurrent flank alopecia

6 parasitic skin infections in dogs and write the agents

Flea infestation - Ctenocephalides felis, C. canis, Ceratophyllus erinacei, C. galinae, Pulex irritans,

Scabies - Sarcoptes scabei var canis, Cheyletiellosis - Cheyletiella yasguri, Otodectic mange - Otodectes cynotis, Demodicosis - Demodex canis, Tromiculosis - Neotrombicula autumnalis, Eutrombicula alfreddugesi

Microorganisms that may induce severe form of otitis externa:

Pseudomonas aeruginosa

Name 4 skin efflorescence

Papule • Macule • Pustule • Vesicle

What is atopy? Clinical signs

Atopy is a hypersensitivity reaction.

Age of onset - 6 months to 3 years

Clinical signs: seasonal, nonseasonal. Pruritus! Mostly secondary lesions due to self-trauma: alopecia, erythema, scaling, hemorrhagic crusts, excoriations, lichenification, hyperpigmentation.

Affected areas: feet, face, ears, flexural surfaces of the front legs, axillae, abdomen.

Secondary skin and ear infections with Staphylococcus and Malassezia are common

Bacteria most common cause of pyoderma in dogs?

Staphylococcus intermedius

6 primary factors which induce otitis externa

Primary factors are diseases that have a direct effect on the external ear canal and can cause otitis

o Otic parasites such as Otodectes cyanotis o Hypersensitivity disease [food allergy, atopic dermatitis, contact hypersensitivity],

o Endocrine disease such as hypothyroidism

o Otic neoplasia

o Foreign bodies.

o (Yeast, bacteria, parasites, allergies, foreign bodies, endocrinopathies)

Name 3 predisposing factors for developing of otitis externa

Predisposing factors are factors that alter the local ear canal environment and increases risk for otitis externa.

Long floppy ears

o Abnormal ear confirmation or anatomy

o Water or hair in ears o Foreign bodies - e.g., grass

o Parasites → otodected cyanotis

o Allergies

o Autoimmune disease

Eosinophilic myositis is?

A rare entity accompanying parasitic infection or other inflammatory disorders

Myotonia

Symmetrical, bilateral, non-purulent alopecia is due to

Hypothyroidism

Pemphigus foliaceus

Most common of the pemphigus complex

• Not specific lesions - (superficial) papules and rare pustules, erythema, crusts, scales, alopecia, erosions

• Pain/pruritus - variable (not usually as itchy as allergy)

• Systemic signs are uncommon

• Secondary pyoderma may be present

• Distribution may involve

o Nasal planum - +/- mucocutaneous junctions

o Ear pinnae - not otitis externa but rather on the pinnae

o Footpads (hyperkeratotic) - may be only signs. Limping can be first signs the owner notice.

o Total body - general distribution

Location of anal sacs

Skin and neck between internal and external anal sphincter - venterolaterally for the anal opening at 4 and 8 o clock position

5 functions of the skin

• Maintaining homeostasis of the body

• Integrity of the body

• Thermoregulation

• Immunological function

• Neurosensorical receptors

• Metabolic function

• Vitamin D synthesis

Steps in checking ears for otitis externa

• A complete medical history

• A complete physical exam including a thorough exam of the entire skin

• Exam of ear with an otoscope - intact ear drum

• Look for foreign bodies or mites in the ear canal and to assess for changes in the health of the ear canal due to chronic disease

• Cytology - which agents are present

• Cultivation, sensitivity - bilateral

• Possible for:

o Biopsy - abnormal masses, tumors

o Myringotomy - edema and discoloration of drum - sample of aspirate

o X-rays - ventrodorsal, lateral - with open mouth

▪ Tumors, effusions

o CT evaluation can be essential if the infection is in the deeper structures

Most common parasite associated with otitis in cats

Otodected cynotis

Symmetrical bilateral pruritic problems (mc)

• Food allergy, hypothyroidism, atopy are mentioned

• Hypothyroidism - more bilateral symmetrical lesions but not often pruritis

• Atopy - lesions are often bilateral, symmetrical and pruritic

• Food allergy - same as atopy

Which bacteria is typical for pyoderma

Staphylococcus pseudointermedius

Clinical signs of otitis externa

Head shaking, scratching, holding of head to affected side, pain, odour, changes in behaviour, edema, erythema, wax production, change in colour and consistency

Clinical signs otitis media and interna (mc)

OTITIS MEDIA

o Same as otitis externa, chronic process, transmission of pharyngeal infection, hematogenous infection, salivation, absent palpebral reflex

o Hornerov syndrome - ipsilateral miosis, ptosis (drooping of the upper eyelid), enophthalmos, keratitis sicca (dry eye syndrome)

OTITIS INTERNA

o Holding of head to one side, circling, nystagmus (eye spasms), vomitus, deafness if bilateral affection, ataxy

Hotspot (acute moist lesions) appearance

Moist, erythematous areas

Which sites are predisposed for atopy?

Feet, face, ears, armpits, front legs?

Different techniques used for detection of skin cytology?

Thin needle aspiration

Clinical signs of inner and middle ear infection

Otitis media:

o Same/similar symptoms as otitis externa

o Salivation, absent palpebral reflex

o Horner's syndrome - ipsilateral miosis, ptosis, enopthalmus

o Keratitis sicca

Otitis media:

o Usually more severe. Typical signs of otitis is missing

o Holding of head to one side

o Circling

o Horizontal or rotation nystagmus

o Vomitus

o Deafness if bilateral affection

o Ataxy

Minimum days for AB therapy in pyoderma

21 days

Parts of eosinophil complex in cats:

Eosinophile granuloma, Eosinophile ulcer

Etiological agent of deep pyoderma

Staphylococcus pseudointermedius

Hypothyroidosis - write etiology, predisposed breed and clinical signs

• Is associated with primary thyroid dysfunction caused by ALT or idiopathic atrophy

• Giant-breed dogs are occasionally affected

• Clinical signs

o Hair coat may be dry, dull and brittle

o Bilaterally symmetrical alopecia that spares the extremities, with easily epilated hairs

o Alopetic skin may be hyperpigmented, thickened or cool to the touch

o Alopecia on the bridge of the nose

o Chronic seborrhea sicca or recurrent otitis externa can be seen

o Seborrheic skin and ears may be secondarily infected with yeast or bacteria

o In some dogs, the only symptom is recurrent pyoderma or adult-onset generalized demodicosis

o Not pruritus unless secondary pyoderma, Malassezia infection, or demodicosis

• Noncutaneous symptoms: Lethargy, mental dullness, exercise intolerance, obesity, cold intolerance, bradycardia

Secondary effloresences

• Squama

• Crust

• Eschara

• Erosion

• Excoriations

• Ragada

• Fissura

• Ulcer

• Sinus

• Comedo

• Cicatrix

What is included in eosinophil complex?

• Eosinophilic plaque (bald patches with raised areas of reddened skin, often on hindlegs and stomach)

• Eosinophilic granuloma (in mouth, around lips, other parts of the body)

• Indolent ulcers

Dermal signs of endocrine disorders

• Alopecia - bilaterally symmetrical

• Dry, lusterless coat

• Hyperpigmentation of alopetic skin

• Seborrhea

• Secondary infections of bacteria and yeasts

• Pyoderma

At least 4 acquired traumatic alopecia

• Pruritic dermatoses

o Sarcoptic mange

o Malassezia pachydermatis

o Dermatophytosis

o Pyotraumatic dermatitis (hot-spot)

• Physical and chemical assult

Hereditary alopetic skin diseases

• Dystrophy or absence of hair follicles

o Hereditary hypotrichosis

o Canine primary seborrhea

• Abnormalities in the hair shaft structure

o Follicular dysplasia

o Colour dilution alopecia

o Black hair follicular dysplasia

o Pattern alopecia

o Recurrent flank alopecia

Which methods are used for parasitic diagnostics? (Which tests can we use to detect parasite)?

• Skin scraping

o Superficial - sarcoptes scabiei var canis, notoedres cati, otodectes cyanotis, cheyletiella blakei + yasguri

o Deep - demodex canis, demodex felis

• Acetate tape

o Fleas, cheyletiellosis

• Flea combing - cheyletiellosis

• Faecal flotation - sarcoptes

• ELISA - detection of parasitic sensitive antibodies - e.g., in case of scabies

Types of pyoderma

• Surface pyoderma

o Acute moist dermatitis (hotspot)

o Intertrigo (skin fold pyoderma)

• Superficial pyoderma

o Impetigo (non-follicular pustules)

o Superficial folliculitis (follicular pustules)

o Mucocutaneous pyoderma

• Deep pyoderma

o Deep folliculitis and furunculosis

▪ Canine acne

▪ Callus pyoderma

▪ Interdigital pyoderma

▪ Generalized deep folliculitis and furunculosis

• Cellulitis

Mark the clinical signs associated with Malassezia pachydermatis

All of above

3 multiple choice options

Which diagnostic method is used in detection of skin parasitic infestations?

Skin scraping

Mark neurological sign seen in association with diseases of the middle and inner ears

Nystagmus

What is not predilection site of atopy

Dorsal part of body

Horner's syndrome is clinical complication at:

Otitis media

What are the typical clinical signs of acute moist dermatitis in dogs?

All of the above

3 multiple choice options

Hereditary dermatoses in breeds with black hair, which is manifested by their alopecia .... Pigmentation and follicle atrophy is:

Black-hair follicular dysplasia

Colour-dilation alopecia

What is burrowing type of skin mite?

Sarcoptes scabiei var. Canis

Congenital dermatological disease with skin keratinization disorder that begins at puppy age:

Canine primary seborrhoea

Hereditary derma disease episodic follicular dysfunction photoperiod

Recurrent flank alopecia

Most common bacterial organism isolated in canine pyoderma

Staphylococcus pseudointermedius

6 parasitic skin infections in cats + agents

• Flea infestation - Ctenocephalides felis, C. canis, Ceratophyllus erinacei, C. galinae, Pulex irritans

• Notoedric mange - Notoedres cati

• Cheyletiellosis - Cheyletiella blakei

• Otodectic mange - Otodectes cynotis

• Demodicosis - Demodex cati

• Tromiculosis - Neotrombicula autumnalis, Eutrombicula alfreddugesi

Most common ectoparasites of dogs and cats

Fleas - Ctenocephalides felis, C. canis, Ceratophyllus erinacei, C. galinae, Pulex irritans

Clinical signs for Malassezia pachydermaris

• Alopecia, excoriation

• Pruritus

• Lichenification, hyperpigmentation

• Unpleasant body odour

• Cats - waxy otitis externa, chin acne, alopecia, erythema, seborrhea

Which cells are seen in Pemphigus complex?

Acanthholytic cells (big, purple, fried egg cells) are immature, detached keratinocytes that make the hallmark for the Pemphigus complex

Primary skin efflorescence

• Macula

• Papula

• Pustule

• Plaque

• Bulla

• Nodule

• Tuber

• Vesicula

• Urticaria

• Tumours

Which hypersensitivity reaction is involved in the diagnosis of sarcoptes scabiei?

Combination of 1 and 4 hypersensitivity reaction

What is the name of cells that are typical for pemphigus complex

Keratinocytes

Which hypersensitivity reaction is involved in the development of bullous pemphigoid?

2 hypersensitive reaction

What are the characteristic clinical signs of otitis externa

Ear pruritus

Mark the types of pyoderma

All of the above

3 multiple choice options

What is the minimal length of antibiotics administration for an adult dog with first occurrence of a superficial staphylococcal folliculitis/pyoderma?

21 days

Which agent is the most common cause of otitis in allergic dog?

Malassezia pachydermatis

Mark primary skin effloresences

All of above

3 multiple choice options

Mark secondary skin efflorescence

Scar

3 multiple choice options

Which is the most common bacterial microorganism isolated in canine pyoderma?

Staphylococcus pseudinitermidus

A 8- year-old male golden retriever patient developed a pruritic lesion within 2 days. It is located in the thigh area, about 20 cm in size, leading to the lumbosacral area. The dog scratches and licks the lesion intensely. The coat looks out at the site of the lesion, the skin is erythematous, wet. Acute dermatitis is observed. The probable diagnosis is?

Hot-spot

Define atopy, clinical sign

• Genetically predisposed, primary pruritic, type 1 hypersensitivity reaction with age and breed predilection

• It is defined as the genetic predisposition to IgE antibodies production against environmental antigens and can be in three different ways,

o Atopic dermatitis

o Atopic rhinitis

o Atopic conjunctivitis • Intrinsic factors are (without IgE)

o Genetical predisposition

o Immune response

o Skin barrier - hydrolipid, pathogens affinity

• Extrinsic factors (production of IgE)

o Pollens

o Moulds

o Mites

o Food allergens

o S. pseudointermedius, Malassezia spp. etc.

• Clinical signs

o Erythema, macula, small and transient papules (1mm)

o Primary pruritus

Clinical signs in Malassezia patchydermatis

• Intense pruritus

• Unpleasant body odour

• Alopecia

• Otitis

• Lichenification

• Hyperpigmentation

• In otitis externa → brown, waxy discharge

Mode of action of Pemphigus complex

Autoantibodies (mainly IgG) are directed against components of the epidermal cell membrane. Once the antibodies bind to the membrane it eventually leads to the degradation of the desmosomal components - acantholysis (release of the cellular attachments allowing the cells to float, round up or form the subsequent cleft)

Can we use the treatment with "lime sulphur, amitraz, ivermectin" against fleas?

• NO

• Lime sulphur and amitraz in case of scabies (S. scabiei and N. cati)

• Ivermectin for fleas

Hornerov's syndrome is clinical complication at

Otitis media

Non-cutaneous signs of hyperadrenocorticism in cats or dogs

• Obesity

• Lethargy

• Heat intolerance

• Exercise intolerance

• Bradycardia

Which flea species most commonly infects cats?

Ctenocephalides felis

Indications for skin scraping?

• Demodicosis

• Scabies

• Cheyletiellosis (superficial scraping)

• Malassezia (staining later on)

How can the cause of pruritus be definitively diagnosed?

• By response to therapy

• If pruritus eases with ATB, then the cause is bacterial

• If it eases with glucocorticoids, it may be immune related

• If it increases and then decreases with antiparasitic treatment, it is likely demodicosis as the mites die and release metabolites that are pruritic

• It is eases with fungicidals it is yeast related (Malassezia spp., Candid)

Treatment of eosinophilic complex in cat?

• Find and remove the primary cause of the hypersensitivity

• Glucocorticoids to ease the immune response

• Prednisolone

• ATB/ fungicidals to treat secondary bacterial/yeast infection

A 14-year-old spayed female poodle is presented with progressive hair loss. Physical examination reveals sparse truncal hair, thin skin, areas of hyperpigmented thickened skin that feels slightly gritty. The owner reports that the skin problem does not bother the dog, blood sample is taken for diagnostics, two hours later the owner phones and reports that the dog has huge bruise at the site of venipuncture. The vet knows that the venipuncture is atraumatic because he drew the blood himself. The most likely diagnosis in this dog is

Hyperadrenocorticism

Which ectoparasites is most commonly seen in dogs?

FLEAS - the correct option is Ct. Felis

Typical symptoms of yeast infection

• Pruritic

• Malodorous

• Alopecia

• Lichenification

• Hyper-pigmentation

• In ears: cerumen is waxy, brown and malodorous

Name the pemphigus complexes

• Pemphigus foliaceous (most common)

• Pemphigus erythematous

• Pemphigus vulgaris (rare)

• Pemphigus vegetans (benign) - more localised form of PV

Symmetrical, bilateral alopecia without pruritus is due to

Hyperadrenocorticism, hypothyrosism, hyperestrogenism

Clinical signs of endocrine dermatitis

• Alopecia

• Polyuria/polydipsia

• Polyphagia or anorexia

• Muscle weakness

• Increased susceptibility to infections

• Variable neurological and behavioural signs

• Bilateral, symmetrical non-pruritic alopecia

Is the Cheyletiella infections?

Yes, very contagious

Is eosinophilic plaque in cat infectious?

No, it is a hypersensitivity reaction

Acquired non-traumatic alopecias

• Endocrinopathy

• Anagen and telogen dysplasia

• Folliculitis

• Perifolliculitis (Sebaceous adenitis, Alopecia areata)

• Tumours (epitheliotropic lymphoma)

• Deep pyoderma

• Dermatomyositis

• Canine idiopathic bald thick syndrome

• Feline preauricular and pinnal alopecia

• Demodicosis

Differential diagnosis of atopy

• Take history

• Age and breed of animal

• Recurrent infections

• Concomittant signs

• Seasonability

• NO - its food allergy reactions, demodicosis, scabies, secondary pyodermas, alopecia etc

Define complex lupus erythematosus

• Its a rare multisystemic autoimmune disorder

• Divided to systemic lupus (SLE) and discoid lupus erythematosus (DLE)

• Genetic factors, drugs, viruses, hormones and immunological deficiencies can be initiative

• Production of autoantibodies with cell or tissue specificity, against erythrocytes, leykocytes and thrombocytes

• The antinuclear antibodies bind to free DNA - form DNA-antiDNA immuno complexes which deposit in glomerulus (glomerulonephritis), arterial wall (fibrosis and necrosis of vessels) and synovia (arthritis)

Clinical signs of DLE

• Inital phase - planum nasale→depigmentation and erythema, later erosions, ulcers and crusts

• Eyelids, mouth, oral cavity, ears and footpats become infected

• Very easily traumatised and bleeding of planum nasale

Clinical signs of SLE

• Limping because of polyarthritis and polymyositis

• Skin lesions in 30-50% of cases

• Involvement of facial region, ears, extremeties, mucocutaneous junctions, oral cavity

• Alopetic lesions

• Erythema

• Ulcers

• Urticaria

What is the most common autoimmune disease in dogs?

Pemphigus foliacus

What is the most common allergic skin disorder in dogs?

Flea allergy dermatitis

What is the primary sign of atopy?

Pruritus

Which mites are burrowing?

• Demodex canis

• Sarcoptes scabiei

• Notoedres canis

is demodicosis contagious?

• Only in the first 72 hours the newborn can become infected by the mother during nursing

• Overall, it is not contagious

Is eosinophilic complex in cats pruritic?

• Eosinophilic plaque follows and intense pruritus

• Eosinophilic granulomas are non-pruritic

Therapy of eosinophilic complex

• Removal of the causative agent

• Glucocorticosteroid therapy

• Prednisone

• Antihistamines

Diagnosis of SLE or DLE

• Presence of either 2 major or 1 major and 2 minor clinical signs

• ANA test - only positive in 5% cases

• Immunofluoroscence, Immunoperoxidase test

• Cytological tests are NOT effective

• Histopathological examination is the most important!

Define the major and minor signs of SLE and DLE

Major signs = Polyarthritis, Polymyositis, Skin lesion, Anaemia, Neutropenia, Thrombocytopenia, Glomerulonephritis

Minor signs = Fever with no known origin, CNS signs – spasms, Noninfectious pleuritis

Diagnosis of Pemphigus complexes

• ANA test - 50% of the time positive in case of PF

• Immunofluoroscence and Immunoperoxidase test

• Cytological examination - detect Ne, Eo and Acantholytic keratinocytes

• Histopathological examination

• Hematology and Biochemistry are not effective

Bullous pemphigus, define

• Rare, similar to PV

• Production of antibodies against the desmosomes found in lamina lucida of the basal membrane

• Pruritus is variable

• ANA test is negative while IF and IP are positive. Histopathlogical test important

Nonspecific changes in case of atopy?

• Excoriation

• Lichenification

• Hyperpigmentation

• Alopecias

Favrots criteria of atopy

• Age of onset less than 3 years

• Dog living inside

• Corticosteroid reacting pruritus (set 1) but pruritus without lesions (set 2)

• Chronic or recurrent malassezias infections

• Forelimb affection

• Affections of the ear flabs

• Nonaffected ear tips

• Nonaffected dorsolumbar region

Clinical signs of FAD

• Variable and highly dependent on frequency of flea exposure, duration of the disease, presence of secondary bacterial or other skin diseases, degree of hypersensitivity reaction and response to previous or concurrent treatment

• PRURITUS (intense and may cover the entire body)

• Papulocrustous lesions on the caudal part of the body - the first clinical signs usually develop in that region

• Traumatic moist dermatitis (Hot spots) may also develop