49. Congenital skin diseases in dogs and cats. Principles of treatment strategies of skin disorders Flashcards
Congenital skin diseases ( Alopecia)?
Congenital Skin Diseases
ALOPECIA
Hypotrichosis congita
Generalised
Breeds selected for alopecia: Abyssinian dog; African sand dog
Pathological alopecia: Belgian shepherd; Whippet; Beagle;
Basset hound; Bichon Frisé
Hypotrichosis: Cats: Devon rex; Siamese
Black hair follicle dysplasia
Predisposed: Bearded collie; Dachshund; Papillon; Basset
Clinical signs:
Occur from 4 weeks old
§ Hairs fall out
§ Ø Hair growth
§ Scaling skin
Colour mutant alopecia
“Blue Doberman syndrome”; “Blue dog disease”
Predisposed: Red & beige Doberman; Fawn Irish setter
Clinical signs
Occur from 1-3 years old
§ “Moth-eaten” alopecia on the back
§ Scaling skin
§ Papule formation
Diagnosis: Skin biopsy (showing cystic follicles with keratin)
Pattern alopecia
Predisposed: Dachshund
Clinical signs
§ Bilateral alopecia of the pinnae (in males)
§ Ventral alopecia (in females)
Does not respond to treatment
Melanoderma & alopecia of Yorkshire terriers
Clinical signs
Occur from 6 months – 3 years; Seen on the nose & legs
§ Melanoderma
§ Alopecia
Congenital Pigmentation defects?
CONGENITAL PIGMENTATION DEFECTS
Hereditary vitiligo
Predisposed: German Shepherd; Belgian Shepherd; Rottweiler;
Doberman; Old English Sheepdog; Dachshund
Clinical signs: Hypopigmentation of the nose, lip, buccal
mucosa, facial skin, footpads & nails.
Canine cyclic haematopoiesis
Grey collie syndrome; Fatal
Clinical signs
Occur at 6-12 weeks old
§ Non-regenerative anaemia § Pyrexia
§ Lymphadenopathy § Diarrhoea
§ Arthralgia
Tyrosinase deficiency in chow-chows
Caused by impaired synthesis of melanin
Predisposed: Puppies
Clinical signs
§ Pink tongue
§ Hair shafts turn white (these recover spontaneously)
Abnormalities of structural integrity?
ABNORMALITIES OF STRUCTURAL INTEGRITY
Aplasia cutis
Epitheliogenesis imperfecta
Caused by focal absence of epithelium
Clinical sign: Ulcer-like lesions
May or may not be fatal (mild cases may heal)
Cutaneous asthenia
Ehlers-Danlos syndrome; Rubber puppy disease; Fibrodysplasia
elastica
Caused by dysplasia of collagen
Predisposed: Beagle; Dachshund; Boxer; St. Bernard; German
Shepherd; Doberman; Himalayan cat; Domestic short hair cat
Clinical signs
§ Joint hyperflexibility § Poor healing
§ Velvet-like skin § Multiple scars
§ Highly flexible skin § Vasopathies
§ Tearable skin (Ø bleeding) § Soft skin
§ Cardiac valve disorders
Dermatomyositis
Predisposed: Rough collies; Shetland sheepdogs
Clinical signs
Occur at 3 months old
§ Papule* § Bony prominences on feet
§ Vesicles* § Muscle atrophy
§ Pustules* § Crusts*
*Found on the nose, eyes, pinnae & tail
Canine ichthyosis
Fish skin disease
Clinical signs: Hyperkeratosis on skin & foot pads
Treatment: Anti-seborrheic & keratolytic ointment
Other diseases?
OTHER DISEASES
§ Zinc-responsive dermatosis in husky & malamutes
§ Schnauzer Comedy syndrome (male Schnauzer)
§ Sebaceous adenitis (Vizsla; Akita; Samoyed; Poodle)
§ Acanthosis nigricans in Dachshund
§ Primary idiopathic seborrhoea
Systemic antihistamines?
Principles Of Treatment Strategies In Skin Disorders
Dermatological therapy can be divided into topical & systemic therapy
SYSTEMIC ANTIHISTAMINES
May be used as antipruritic or anti-inflammatory agents in skin
disorders
§ Hydroxyzine
§ Chlorpheniramine
§ Cetirizine
§ Astemizole
Treating Autoimmune skin diseases?
TREATING AUTOIMMUNE SKIN DISEASES
In cases such as pemphigus foliaceus & systemic lupus
erythematosus (SLE)
The goal of this treatment is immunosuppression
Dog
§ Prednisolone PO + Azathioprine
§ Supplemental antibiotics as required
Cat
§ Prednisolone only
§ Cyclosporine only
Topical drugs?
TOPICAL DRUGS
Medical shampoos & solution
Kerato-modulating agents:
Used for kerato-seborrhoea; Infection
§ Salicylic acid § Coal tar
§ Selenium disulphide § Sulphur
§ Ammonium acetate
Anti-seborrheic agents:
§ Selenium disulphide § Vit. B6
§ Benzoyl-peroxide § Sulphur
§ Zinc gluconate
Antiseptic agents:
§ Chlorhexidine
§ Ketoconazole
§ Miconazole
Topical anti-inflammatories
Emulsion; Spray; Solution; Ointment; Cream; Gel; Wipes
§ Glucocorticoid
§ Neomycin + Prednisolone
§ Tacrolimus
§ Antioxidant (Vit. E)
