Scaling or Greasy Skin Flashcards
seborrhea sicca
dry form
seborrhea oleosa
greasy form
seborrheic dermatitis
accompanied with by inflammation
seborrhea
disorders of the skin resulting in excessively scaly or greasy skin
seborrhea can be produced by disorders that cause
altered cellular proliferation, differentiation or desquamation
in addition to flaky or oily skin and hair, how can patients present with seborrhea
malodor or pruritus
general causes of altered cellular proliferation, differentiation or desquamation
any cause of inflammation, endocrine imbalances, nutritional factors and environmental factors
major differentials for scaling or greasy skin
malassezia dermatitis, sebaceous adenitis, keratinization disorders (primary idiopathic seborrhea), pyoderma/bacterial overgrowth syndrome, demodicosis, dermatophytosis, vitamin a responsive dermatosis, endocrine skin disease, cheyletiella, ichthyosis, cutaneous lymphoma, paraneoplastic disorders
what diagnostic test is very significant in scaling or greasy skin
skin scrapings and cytology
three major causes of crusting
pyoderma, demodicosis, dermatophytosis
what is malassezia dermatitis
a fungal skin infection caused by a lipophilic commensal yeast
most common cause of malassezia dermatitis
malassezia pachydermatis
true or false: malassezia dermatitis is more common in dogs than cats
true
which bacteria is malassezia said to have a symbiotic relationship with
staphylococci
does malassezia invade the skin
no, proliferates on the surface
what does the surface over-proliferation of malassezia cause
inflammatory or hypersensitivity reactions to the products of the yeast
what areas of the body does malassezia thrive in
areas with of skin with higher humidity, skin folds, greasy (seborrheic) skin and in areas with staphylococcal overgrowth
which breeds have a genetic predisposition to malassezia overgrowth
shih tzu, lhasa apsos, west highland white terriers, basset hounds and devon rex cats
what underlying conditions can be associated with malassezia
atopic dermatitis, seborrheic disorders, pyoderma, endocrine disorders
what clinical sign is a consistent feature in malassezia dermatitis
pruritus – can be severe
which areas are commonly affected in malassezia dermatitis
feet, lip folds, nailbeds, ventral neck, other folds
lesions of localized malassezia dermatitis
erythematous, greasy, brown discoloration
lesions of generalized malassezia dermatitis
erythematous, greasy, scaly, crusty, rancid odor (corn chips)
what do cats most commonly show with malassezia
otitis externa
diagnosis of malassezia dermatitis
cytologic exam – tape preparation
how many yeast are significant for malassezia dermatitis
1 or more per oil immersion field
are fungal cultures useful in diagnosing malassezia dermatitis
no
can skin biopsies diagnose malassezia dermatitis
it can but is also very easy to miss the organism
treatment of malassezia dermatitis is best done with a combination of
systemic and topical therapy
with what drug and for how long is malasezzia treated systemically
ketoconazole for 7 days past a clinical cure (2-4 weeks total)
which animals should ketoconazole not be used in
cats;
dogs with liver disease
when an animal is on an antifungal drugs systemically, what should clients do if lethargy or inappetence occur
stop immediately – rare potential for idiosyncratic hepatopathy
which drugs does ketoconazole interact with
cyclosporine, ivermectin
examples of topical therapy for malassezia dermatitis
shampoos containing miconazole or selenium sulfide or ketoconazole
what is the best topical treatment for malassezia dermatitis that is not yet available in canada
miconazole + chlorhexidine shampoo
what is key to controlling malassezia overgrowth recurrence in patients
control any concurrent disease or underlying condition
what is granulomatous sebaceous adenitis
an idiopathic, heritable inflammatory skin disorder in dogs affecting sebaceous glands in young to middle ages dogs
what occurs regarding the sebaceous glands in sebaceous adenitis
progressive destruction of sebaceous glands and with that loss of sebum production
breed predisposition to sebaceous adenitis
standard poodle (autosomal recessive), samoyed, akita
signs of sebaceous adenitis
progressive areas of hair loss, poor hair coat, dry hair, excessive scaling and follicular plugging and casts
what endocrine disease is it easy to mistake sebaceous adenitis for
hypothyroidism
what secondary infection is common with sebaceous adenitis
pyoderma
diagnosis of sebaceous adenitis
characteristic inflammatory pattern or with chronic cases you can see absence of sebaceous glands – skin biopsy
treatment of sebaceous adenitis aims to
restore oil to skin surface and hair follicles
treatment options for sebaceous adenitis
fatty acid supplementation;
topical therapy is key – bath oil to wet skin;
cyclosporine
what is primary idiopathic seborrhea
a disorder of keratinization leading to more rapid epidermal cell renewal time
what breed is primary idiopathic seborrhea common in
cocker spaniel
what is the epidermal cell renewal time in a cocker spaniel with primary idiopathic seborrhea
8 days (versus normal at 21 days)
common findings with primary idiopathic seborrhea
dull coat, excessive flaking, greasy malodorous skin, otitis externa;
can see digital hyperkeratosis and brittle claws
diagnosis of primary idiopathic seborrhea
skin biopsy and exclusion of other causes of scaling/greasy skin
why is it important to exclude other causes of scaling/greasy skin in patients with primary idiopathic seborrhea
because primary and secondary seborrhea look histologically similar
is primary seborrhea curable
no, but is manageable with shampoos and conditioners
true or false: secondary infections commonly occur with primary seborrhea and are important to control
true
in addition to shampoos and conditioners, what can be used to treat dogs with primary seborrhea
omega-6 and omega-3 FA
what is vitamin A responsive dermatosis
condition in cocker spaniels with ADULT ONSET that is characterized by marked follicular plugging and hyperkeratotic plaques
how is a diagnosis of vitamin A responsive dermatosis made
response to vitamin A therapy
