Acquired Alopecia

Question 0

What is the actively fully growing stage?

Answer 0

Anagen

Question 1

Find flow chart on learn

Question 2

What occours at catagen?

Answer 2

Follicular epithelium retracts upwards, dermal papilla starts to migrate upwards

Question 3

What happens during telogen?

Answer 3

Hair anchored, dermal papilla close to surface and inactivve

- nothing much happening

Question 4

which hormones regulate hairgrowth? What else affects hairgrowth?

Answer 4

• thyroid
• GCs
• sex hormones
• IGF-1
• PRL, melatonin
  > nutrition
  > regional differences
  > local differences (hormonesmediators, growth fctors, cytokines)

Question 5

Define alopecia

Answer 5

• baldness or loss of hair

Question 6

Define hypotrichosis

Answer 6

Mild alopecia or congenital alopecia

Question 7

Define the problem of alopecia

Answer 7

1* alopecia  
- damage/loss  follicle (eg. burns) 
- cell cycle arrest (eg. chemo)
- dysfunctional follicle
2* trauma (self trauma or rubbing tack etc.)

Question 8

Refine the problem of alopecia

Answer 8

• inflammatory
  > inflam may be targetted at hair follicle or epidermal spread to/accidentally affecting follicle (bystander eg. leishmaniosis)
  > hair follicle (bacterial, dermnatophytes, demodex causes)
• non-inflammatory
  > endocrine (other signs should be present, hairs arrest in telogen phase: telogenisation)

Question 9

What is alopecia X?

Answer 9

• unclear aetoiology
• cosmetic problem only
• local endocrine problem? no systemic problems found

Question 10

Rarer causes of alopecia?

Answer 10

> miscellanesous hair cycle/growth problems
- colour linked alopcia in dilute breed (melanin clumping in hair shaft makes them weak and they break off)
- recurrent flank alopecia (symmetrical, hyperpigmentation, cosmetic problem, recurs annually then grows back, tx with sunscreen!)
- irish water spaniels breed for some areas long coat and some patches of short coat -> selecting for distorted hair follilces
- patterns baldness (miniaturisation of hari follicles)
other causes (rare)

Question 11

Outline diagnostic approach to alopecia

Answer 11

> selfinflicted traumatic removal - work up as pruritis
inflammatory (demodex, staph, dermatophytosis)
non-inflam - r/o endocrine , histopathg

Question 12

What syndrome do greyhounds and whippets get?

Answer 12

• bald thigh syndrome
  > thyroid related?
• normally low thyroid anyway

Question 13

Non-inflammatory alopecia tx?

Answer 13

• if not causing a problem do not treat!

- some people treat with a steroid hormone thing (look up)