Pathophys-Day 3 Hair

Question 1

How long does the anagen hair phase last?

Answer 1

1-5 years

Question 2

How long does the telogen hair phase last?

Answer 2

3 months

Question 3

When does hair grow fastest and slowest?

Answer 3

Summer, winter

Question 4

Approx what percentage of hair is in the anagen phase?

Answer 4

90%

Question 5

Pathogenesis of Androgenic alopecia

Answer 5

Miniaturization of hairs with transformation of large terminal follicles to small vellus follicles (visible to invisible)

Question 6

Describe the progression of male pattern baldness

Answer 6

Frontotemporal + vertex recession

Question 7

Describe the progression of female pattern baldness

Answer 7

Retain frontal hairlines, but decreased density on crowns

Question 8

Compare onset of male and female alopecia

Answer 8

Female delayed compared to males. 25-35 onset for women while 10 yrs younger for men

Question 9

What should one do to confirm a diagnosis of androgenic alopecia?

Answer 9

Check DHEAS and testosterone blood levels

Question 10

What is the inheritance pattern of androgenic alopecia?

Answer 10

AD or multifactorial

Question 11

Tx for androgenic alopecia?

Answer 11

Minoxidil
Antiandrogens - finasteride
Hair transplants

Question 12

Minoxidil MOA

Answer 12

Inducing anagen or inc anagen duration
Inc hair diameter

5% is best

Question 13

Finasteride (Propecia) MOA

Answer 13

Type II 5-a-reductase inhibitor (conversion of testosterone into 5-DHT)

Question 14

Finasteride AEs

Answer 14

Lingering sexual side effects even after therapy

Question 15

Telegen effluvium pathogenesis

Answer 15

Premature switch from anagen into telogen results in shedding 20-35% of hair

Question 16

Normally, how many hairs per day after shed?

Answer 16

100

Question 17

Telegen effluvium presentation

Answer 17

6 wks - 3 mo after precipitating cause
Inc hair pull
Regrows within 6-12 months

Question 18

What are some potential causes of telogen effluvium?

Answer 18

Birth
Fever
Surgery
Drugs
Autoimmune
Trauma
Infections
Emotional Trauma

Question 19

Treatment for telogen effluvium?

Answer 19

2% minoxidil

Question 20

Anagen effluvium pathogenesis

Answer 20

Acute, extreme alteration of growth of anagen hair resulting in 80+% hair loss 1-2 weeks after cause

Chemo
Mercury
Thalium
Anticoagulants

Question 21

How does drug alopecia present?

Answer 21

telogen effluvium, on scalp but can affect other hair

often over ears

Question 22

What pattern of hair loss does alopecia areata cause?

Answer 22

Circular areas of complete hair loss with normal scalp

Can even progress to loss of all scalp hair and all body hair

Question 23

What does alopecia areata show on biopsy?

Answer 23

‘Swarm of bees’ - lymphocytes around hair bulb

Question 24

Alopecia areata prognosis and tx

Answer 24

hair may grow back white and change curly/straight

hair regrows

Question 25

Alopecia areata treatment

Answer 25

Topical steroids; anthralin, minoxidil, immunotherapy

Question 26

Traction alopecia pathogenesis and appearance

Answer 26

Rollers, weaves, perms, etc.

Peripheral fringe! Can scar if bad

Question 27

Traction alopecia complications and tx

Answer 27

S aureus folliculitis
Dermatophyte infection

Tx: stop cause

Question 28

What organism usually causes folliculitis?

Answer 28

S aureus

Question 29

Folliculitis treatment

Answer 29

Oral antibiotics
Consider MRSA
Shampoos

Question 30

Secondary syphillis appearance, dx?

Answer 30

Moth-eaten

Rapid plasma antigen test +

Question 31

When a patient complains of hair loss, what should you do/check/order?

Answer 31

Physical exam - scalp disease
CBC (anemia)
Ferritin
TSH