Endocrine, Metabolic, Hereditary, Nutritional, and Environmental Skin Diseases Flashcards
what is alopecia like with endocrinopathies?
non-inflammatory
truncal
what happens in canine and feline hyperadrenocorticism?
chronic excessive secretion of glucocorticoids
what does the pars distalis secrete?
ACTH
beta-lipoprotein
why should pyoderma and adult-onset generalized demodicosis be ruled out with hyperadrenocorticism?
skin immunosuppression
how do glucocorticoids cause skin fragility syndrome in cats?
inhibit collagen I and III transcription
who is affected by hyperestrogenism?
mostly dogs
both sexes
english bulldogs overrepresented
what can cause hyperestrogenism in an intact male?
functional testicular tumor
what do estrogens induce that can be seen on preputial/vaginal cytology?
superficial cells
what is the age of onset for alopecia X?
9 months-2 years
what do dogs with hepatocutaneous syndrome have?
skin lesions
hepatopathy
hypoaminoacidemia
aminoaciduria
what do hypoaminoacidemia, hyperglucemia, aminoaciduria lead to?
death keratinocytes
vacuolar hepatopathy
what is ehlers-danlos?
heterogenous group of heritable phenotypically overlapping diseases that affect collagenogenesis (connective tissue)
how do endocrinopathies affect the hair cycle?
anagen onset is impaired
anagen is shortened
what is the hallmark of endocrinopathies?
alopecia: non-inflammatory, truncal
is there a breed predilection for hyperadrenocorticism?
no
what is feline and canine hyperadrenocorticism?
chronic excessive secretion of glucocorticoids
what are animals with endocrinopathies predisposed to?
pyoderma
demodicosis
due to skin immunosuppression
after __________ topical glucocorticoids can induce skin atrophy (decreased thickness)
14 days
do any histologic features consistently differentiate the endocrinopathic diseases?
no
what do glucocorticoids inhibit that leads to skin fragility syndrome in cats?
collagen I and III transcription
what does canine hypothyroidism result from?
decreased productin of thyroxine/T4 and tri-iodo-thyronine/T3
is there a familial and breed predisposition to canine hypothyroidism?
yes
what dermatologic findings are in canine hypothyroidism?
alopecia
dry/poor coat quality
skin hyperpigmentation
seborrheea
predisposition to pyoderma
myxedema: “tragic facial expression”
what can cause feline hypothyroidism?
iatrogenic after treatment for hyperthyroidism
congenital
acquired
very rare
what causes hyperestrogenism in an intact female?
polycystic ovaries- English bulldogs
functional ovarian tumor
what is anti-mullerian hormone?
very sensitive and specific for sertoli cell tumor
hyperestrogenism
who is predisposed to alopecia X?
plush dogs
pomeranians
nordic breeds
chow chow
keeshond
miniature poodle
males>females
why is alopecia seen with alopecia X?
anagen onset impaired, do not know why
what would support alopecia X on a skin biopsy?
few anagen bulbs
increased telogen (significant compared to other hair cycle arrest diseases)
increased kenogen with follicular atrophy and excessive trichilemmal keratinization (flame follicles)
what can you use to treat alopecia X?
cosmetic
melatonin
castration
deslorelin
what is SND/skin lesions an umbrella term for?
endocrine neoplasia- necrolytic migratory erythema
liver disease- hepatocutaneous syndrome
what liver changes are seen in hepatocutaneous syndrome?
foci of regenerative nodular hyperplasia separated by areas of parenchymal collapse containing heavily vacuolated hepatocytes
how common is hyperkeratosis of footpads in hepatocutaneous syndrome?
96%
what indicates a diagnosis of hepatocutaneous syndrome?
compatible or suspicious clinical signs
hypoaminoacidemia and aminoaciduria
liver changes in ultrasound: honeycomb or swiss cheese
what amino acid biomarkers for hepatocutaneous syndrome are present in plasma?
1-methylhistidine
cystathionine
what is ehlers/danlos genetic diseases?
heterogenous group of heritable phenotypically overlapping diseases that affect collagenogenesis- connective tissue
abnormal collagen I, III, or V
what can you use to increase the likelihood of a diagnosis of ehlers/danlos?
skin extensibility index (stretch of skin)
skeletal deformities
skin tears
what is dystrophy?
follicular reconstitution is impaired due to an acquired deregulation of signaling events
what is in the neuroectoderm?
melanocytes and neural tissues
what is dysplasia?
follicular development during organogenesis is impaired due to inherited defect
which cats are predisposed to follicular dysplasia?
cornish rex
how can you treat follicular dysplasia?
cosmetic
no treatment
look for secondary
avoid harsh grooming
avoid sun
what clinical syndromes related to zinc are described in dogs?
inherited impairment in absorption/metabolism Zn primarily in nordic breeds
rapidly growing or young adult dogs that are fed Zn-deficient or high phytates, calcium, copper, iron
what is the most relevant feature on histopathology with a zinc related condition?
marked, diffuse parakeratosis: parakeratotic hyperkeratosis
parakeratosis: increased thickening of stratum corneum with retained nuclei
what is phototoxicity?
dose-related response to light exposure
what is photoallergy?
skin has increased sensitivity to UV because of a photodynamic agent
mostly farm animals
