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Flashcards in Hair loss Deck (17)
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What stage of growth are most hairs in?

anagen (>80%)


How is hair growth regulate? 4

- NUTRITION - and metabolic ddiseases
- CENTRAL SYSTEMIC HORMONES - TH, GCs, sex hormones, IGF1, PRL, melatonin
- REGIONAL - differential response to mediators
- LOCAL - hormones, mediators, growth factors, cytokines


Differentiate alopecia and hypotrichosis

ALOPECIA = baldness, absence of hair which is normally present, loss of hair
HYPOTRICHOSIS - congenital alopecia or paucity of hair


How can the problem of hair loss be define?

Primary alopecia versus traumatic hair loss (due to pruritus and other mechanical factors)


What are the 4 main categories of causes of hair loss?

- trauma
- follicle destruction
- disruption of hair growth
- deformation of hair follicle


What should you do if a cat presents with symmetrical alopecia?

Probably self-inflicated unless proven otherwise (owners likely to deny this) so work up as self-trauma


How do you refine the problem of hair loss?

Inflammatory versus non-inflammatory


What are the 2 types of inflammatory hair loss?

1.) dermal inflammation with a hair follicle as a bystander (Leishmania)
2.) dermal inflammation that specifically targets a hair follicle (Demodex, Dermatophytes, bacterial folliculitis)


What are the 2 types of non-inflammatory hair loss?

1.) dysfunctional hair cycle
2.) problem with hair follicle structure


How do endocrine disorders generally affect hair growth?

arrest hair growth in the telogen phase


What are 3 classic signs of Cushings in dogs?

- mm loss
- thin skin
- distended abdomen


What is alopecia X?

- hair growth of unknown origin, possibly endocrine but no consistent hormonal abnormality and no consistent reversal of abnormality on successful treatment
- some evidence of abnormal adrenal steroidogenesis and some response to steroidogenesis inhibitor but unknown significance
- may only be a cosmetic problem


What are the 4 main categories of acquired non-traumatic alopecia?

- endocrinopathies
- coat colour-linked
- miscellaneous hair cycle/growth problems
- other (rare)


What is (recurrent) flank alopecia?

- hyperpigmentation when hair is lost
- usually dogs healthy, only cosmetic, remember sunscreen
- breeds: Airedales, Boxers, Bulldogs, Schnauzers, Rhodesian ridgebacks


What is the cause of pattern alopecia?

(i.e. this is alopecia in specific regions)
- due to miniaturisation of hair shafts
- a type of follicular dystrophy/dysplasia


How do you work up a case of alopecia that you suspect is inflammatory (i.e. infectious)?

diagnostic tests to investigate demodecosis, bacterial folliculitis (staph) and dermatophytosis. If not consider endocrine diseases. Then look up miscellaneous alopecias (especially breed-related).


Are inflammatory or non-inflammatory skin diseases most common in general practice?