Alopecia associated hormonal diseases Flashcards
List the 4 types of hormonal alopecia
- Hypothyroidism
- Hyperadrenocorticism
- Sex hormone imbalance (estrogen)
- Alopecia X
What is the pathophys behind why hypothyroidism can cause alopecia?
- Thyroid hormones promote anagen
- Lack of thyroid hormone delays anagen (delays hair growth)
List hormones that promote the anagen phase of the hair growth cycle
- Thyroid hormones
- Melatonin
- Prolactin
What is the pathophys behind why HAC/Cushings can cause alopecia?
- High cortisol levels DELAY Anagen phase (delays hair growth)
What cutaneous signs can be seen in patients with HypoT?
- Symmetric non-pruritic alopecia
- THIN hair coat
- Easily epilated
- Rat tail
- Failure to grow post clipping
What is the treatment protocol for patients with symmetric alopecia consistent with HypoT?
- Life long Levothyroxine
Which dog breeds have normally lower T4 values?
Greyhounds and sighthounds
What cutaneous signs can be seen in patients with HAC/Cushings?
- THIN hair coat
- Calcinosis cutis
- Symmetric non-pruritic alopecia
- Comedones
What diagnostic test would you perform to confirm HAC/Cushings?
LDDST test
What is the treatment protocol for patients with symmetric alopecia consistent with HAC/Cushings?
- Trilostane
- Adrenalectomy
What cutaneous signs can be seen in patients with Hyperestrogenism?
- Linear preputial dermatosis in intact male dogs!! Pathognomonic!!
- Symmetric non-pruritic alopecia
- Nipple and vulva enlargement
What diagnostics should you run in an intact patient presenting with non pruritic bilateral alopecia and evidence of linear preputial dermatosis?
Ultrasound!!! of the abdomen and testicles
What is the treatment of choice for a patient presenting with cutaneous signs of hyperestrogenism?
CASTRATE/OVH of intact patients
What is a pathognomonic finding in intact male dogs with hyperestrogenism?
Linear preputial dermatosis!!
What breed is Alopecia X most commonly seen in?
- Pomeranians
What is the distribution pattern seen with Alopecia X?
- Patchy, symmetric, non pruritic alopecia everywhere EXCEPT the head and distal limbs are spared
What is the treatment protocol for Alopecia X?
- Benign neglect
- Or melatonin (stimulates anagen phase)
At what age does pattern alopecia typically present in dogs?
Gradual onset < 1 yr of age
What dog breeds are more represented for pattern alopecia?
- Boston terrier
- Chichi
- Dachshund
- Bull terrier
- Whippet
- Greyhound
What dog breeds are more represented for color dilution alopecia?
- Blue colored dogs
- Doberman
- Chichi
- Italian greyhounds
- Bull terrier
- Any blue colored breed (Frenchies)
What is the pathophys behind color dilution alopecia in blue coated dogs?
- Defective transport of melanosomes leading to melanosome clumping
How can you diagnose color dilution alopecia in a dog?
Trichography to look for melanosome clumping
What clinical signs to dogs with color dilution alopecia typically present with?
- Non pruritic alopecia
- Broken hairs
- History of a blue colored dog
At what age does color dilution alopecia typically present with cutaneous signs?
Progressive from 3 months to 3 years
