Exam 3: Keratinization Diseases Treatment

generally define keratinization disorders

• any issue in the keratinization process

• seborrhea is a description not a diagnosis

• seborrhea sicca is dry ski and scales

• seborrhea oleosa is oily and scaly

• SCALES

primary keratinization disorders

• primary seborrhea

• ichthyosis

• follicular parakeratosis

• schnauzer comedo syndrome

• footpad hyperkeratosis

• hereditary nasal hyperkeratosis in labs 

keratinizations are usually ?

secondary disorders

other causes of keratinization disorders

• vitamin A responsive dermatosis

• feline acne

• canine ear margin dermatoses

• tail gland hyperplasia

• nasodigital hyperkeratosis

keratolytic agents

• break down the outer layer of skin, softening and increasing the shedding of dead skin

  • increases desquamation which is shedding the stratum corneum

keratoplastic agents 

• normalize the rate of skin cell production which reduces the thickness of the skin 

  • actis as cytostatic, inhibiting the division of basal cells 

follicular flushing

agents that help remove follicular debris, secretions, bacteria and decrease the follicular hyperkeratosis

sulfur

• keratoplastic at low dose, keratolytic at high dose

• also antibacterial, antifungal, pantoparasitic, antipruritis

salicyclic acid 

• keratoplastic low, keratolyytic high 

• bacteriostatic, mild antipruritic 

tar

• derived from destructive distillation of bituminous coal or wood

• NO CATS

• keratolytic first, keratoplastic, degreasing

benzoyl peroxide benzoyl peroxide

• keratolytic

• degreasing

• follicular flushing

selenium sulphide 

• keratolytic first, keratoplastic, degreasing 

• NO CATS 

• anti fungal 

Zn gluconate

antiseborrheic

antibacterial

hydroxypyridinethone salts 

keratoplastic 

ammonium lactate

lytic first, then plastic

primary seborrhea

• cocker spaniels, west highland terriers, hounds

• may be associated with yeast ifections and hypersensitivity

• usually start developing signs during puppyhood that worsen with age

• regional to generalized excessive scaling

• greasy otitis externa with or without infection

• seen on ears, folds, feet, perinenum

diagnosis primary seborrhea 

0 rule out! 

cytology, scraping, dermatophyte culture, bloodwork, some degree of semorrhea will remain even when secondary infection is controlled 

treatment primary seborrhea

topical care

monitoring and controling secondary infection

icthyosis

• mutations in keratine genes result in epidermolytic forms of ichthyosis

• mutations affecting the production of lipids, non-keratin proteins or desquation result in non-epidermolytic forms

• scales and no inflammation

golden retriever ichthyosis 

• typically onset less than 1 year 

• scaling may wax and wane, hyperpigmentation, ceruminous otitis externa, footpad hyperkeratosis

• in homozygous puppies scales are seen at a young age that usually disappear

  • diagnosed with biopsy 

treatment golden retriver ichthyosis

• symptomatic

• keratolytic/keratoplastic shampoos (piroctone olamine) twice weekly at beginning then as needed

• fatty acids PO + humectant bath + dermoscent spot on/week

nasodigital hyperkeratosis

• thickened, hard, dry keratin accumulates on the nasal planum, footpads or both. Accumulated keratin usually the most prominent on the dorsum of the nose and at the edges of the footpads. secondary erosions, ulcers and fissures may suggest autoimmne

• congenital-hereditary

• may be idiopathic via senile change, abnormal anatomy, secondary (distemper, papillomavirus, leishmaniosis, PF, PE, drug eruption, Zn responsive, superficial necrolytic dermatitis, cutaneous lymphoma)

treatment of nasodigital hyperkeratosis 

• removal of excess keratin with scissors or blade 

• hydration + keratolytics

• demoscents biobalm 

• systemic retaniods if topical not possible 

• fissures require topical Abx and glucocorticoids 

canine tail gland hyperplasia

• seborrheic, hyperadreogenism, adrenal tumor in castrated males and females, hypothyroidism

• hyperplasia of sebacious ± circumanal glands, or hyperplasia of the sebacious glad and alopecia due to the compression of the hair follicles from the hyperplastic glands

  • due to friction and compression of hair follicles by the hyperplastic galnds

treatment of canine tail gland hyperplasia

• castration

• surgery (will recur if not castrated)

treatment of feline tail gland hyperplasia 

• castration may stop progression 

• antiseborrheic shampoos, benzyl peroxide 

zinc responsive dermatosis

• genetic predisposition in northern breeds

• impaired zinc intestinal absorption

• crusts, alopecia, erythema

• seen on head, pressure points, mucocutaneous junctions, paw pads, scrotum

  • requires life long zinc supplementation

oral zinc options

• zinc methionine

• zinc sulfate

• zinc gluconate

• may cause vomiting, nausea so divide the dose and give it with food

• poor response = consider crushing, add oral steroid, fatty acids, OHE, zinc IV or IM

zinc responsive dermatosis syndrome 2 

• young dogs fed diets which are low in absolute zinc concentration, have high phylate (plant protein) or calcium levels and or are fed cereal or soy based diets 

• crusts, alopecia, erythema 

• tx = feeding a balanced diet, usually only transient zinc supplementation is needed 

sebaceous adenitis

• dogs, rarely cats

• immune mediated attack on sebaceous glands, severe inflammation may ultimately destroy hair follicles

• standard poodles, havanese, samoyeds, akitas, ect

• young adults to middle age

• lesions start on back of neck, dorsum, and pinnae then spread ventrally

sebaceous adenitis in long coated dogs

• light scale → progressive hair loss and changed texture

• later see dull, dry fur and scale adhering to hairs aka follicular casts

sebaceous adenitis short coats 

• poorly defined areas of circular to coalescing alopecia, may havr associated scale or follicular castng 

sebacious adenitis diagnosis

clinical signs

biopsy

differentials for follicular casts

• bacterial pyoderma

• demodicosis

• dermatophytosis

• sebaceous adenitis

sebaceous adenitis treatment 

• cyclosporine 

• tpical kkeratolytic shampoo every 7-30 days 

• other treatments include n-3/n-8 fatty acids, eicosapentaenoic acid, vit A, tetracycline niacinamide, retinoids 

feline acne

• idiopathic disorder of follicular keratinization characterized by comedo formation and secondary inflammation on the chin and skin adjacent to the lips

• papules and pustules ad rarely, furunculosis and cellulitis may develop

• often less than 1 yr and remains lifelong disease

feline acne causes- aggravating factors

• poor grooming habits

• follicular keratinization disorder

• hhair cycle influences

• stress

• bacteria

• calcivirus

• malassezia

• immunosuppression

feline acne treatment 

• clip har 

• cleaning 

• magnesium sulphate for draining lesions 

• Benzoyl peroxide gel 

• tretioin or vitamin A 

• topical mupirocin 

• systemic abx, fatty acids, prednisolone, isotretinon