48. Endocrine dermatopathies in dogs and cats Flashcards
Sex Hormone dependent dermatoses? Sertoli Cell tumour?
Sex-Hormone Dependent Dermatoses
SERTOLI CELL TUMOUR
Predisposed: Boxer; Shetland sheepdog; Poodle; Pekingese; Collie;
Mini Schnauzer; Any breed suffering from cryptorchism
Pathogenesis: Excessive secretion of oestrogen
Clinical signs
§ Preputial swelling § Dermatosis
§ Hyperpigmentation § Alopecia
§ Lichenification § ↓ Libido
§ Feminisation § Attracted by other males
§ Gynecomastia § BM depression
Treatment: Castration
Hyperadrogenismus in male dogs?
HYPERADROGENISMUS IN MALE DOGS
Leydig cell tumour
Predisposed: All breeds; Middle/old-aged
Clinical signs
§ Circumanal gland hyperplasia § Prostatitis
§ Tail gland hyperplasia § Perianal adenoma
§ Severe seborrhoea oleosa § Alopecia
Treatment: Castration
Testosterone Responsive Alopecia?
TESTOSTERONE-RESPONSIVE ALOPECIA
In castrated male dogs
Clinical signs
§ Symmetrical alopecia § Seborrhoea
§ Dry hair § Thin skin
§ Dull hair § Hypotonic skin
§ Lighter hair (initially) § Scaling
Treatment: Methyltestosterone
Castration responsive dermatosis?
CASTRATION-RESPONSIVE DERMATOSIS
Or hypogonadism of intact dogs’ “Dermatosis that responds to
castration”
Predisposed: Entire males; Pomeranian; Chow-chow; Malamute;
Husky
Clinical signs
§ Fine, “fluffy” coat § Hyperpigmentation
§ Symmetrical alopecia (neck; perineum; thighs)
Treatment: Castration
Hyperoestrogenism in females?
HYPEROESTROGENISM IN FEMALES
Predisposed: Middle/old-aged bitches
Aetiology: Cystic ovaries; Cystic tumours
Clinical signs
§ Symmetric alopecia § Seborrhoea
§ Generalised alopecia § Lichenification
§ Abnormal oestrus cycle § Enlarged vulva
§ Enlarged nipples
Treatment: Ovariohysterectomy & symptomatic treatment for seborrhoea
Oestrogen responsive dermatosis?
OESTROGEN-RESPONSIVE DERMATOSIS
In spayed females before first oestrous
Clinical signs
§ Symmetrical perineal alopecia § Puppy-like coat
§ Soft genital region § Small vulva
§ Small nipples
Treatment
§ None
§ Diethyl-stilbestro
Hypogonadism in intact females?
HYPOGONADISM IN INTACT FEMALES
↓ Functional activity of gonads
Predisposition: Poodle; Terrier; Dachshund
Primary hypogonadism: Infertility is treated early → No time for skin lesions to develop
Secondary hypogonadism: → Irregular cycle; Anoestrous
Noncyclic alopecia: <3 years old; Slow progression
Cyclic alopecia: Starts with oestrous → Recovery → May not
recover in time before anoestrous
Diagnosis is performed to exclude hypothyroidism & Cushing’s
Treatment: Spaying
Alopecia X ?
ALOPECIA X
Synonyms
§ “Hyposomatotropism”
§ “Sex hormone-responsive dermatosis”
§ “Castration-responsive dermatosis”
§ “Pseudo-Cushing’s”
May be caused by an abnormality of steroidogenesis (one or more diseases)
Predisposed: Young adults; All males; Spayed females; Poodles
Localisation: Everywhere except for the head & paws
Clinical signs
§ Hyperpigmentation § Scaling skin
§ Broken hair shafts § Dry skin
§ Alopecia § Thin skin
Diagnosis: ACTH-stim (measure adrenal gland hormones); Measure
sex hormones
Treatment
§ Castration/Spay
§ Melatonin
§ Trilostan
§ Mitotan
§ Testosterone
Other Conditions?
Other conditions
§ Hypothyroidism (see Topic 28)
§ Hyperadrenocorticism – Cushing’s (see Topic 30)
§ Diabetes mellitus (See Topic 27)