alopecia (hair loss)

Question 1

3 stages of hair growth

Answer 1

1. growth stage = anagen phase
   .2. transitional stage = catagen stage
2. resting stage = telogen phase

Question 2

categories of alopecia

Answer 2

non scarring or scarring

Question 3

clinical presentation of alopecia

Answer 3

• male-pattern or female-pattern alopecia • males: fronto-temporal areas progressing to vertex, entire scalp may be bald • females: widening of central part, “Christmas tree” pattern

Question 4

management of alopecia

Answer 4

• minoxidil (Rogaine®) solution or foam to reduce rate of loss/partial restoration • spironolactone in women (anti-androgenic effects), cyproterone acetate (Diane-35®) • finasteride (Propecia®) (5-α-reductase inhibitor) 1 mg/d in men • hair transplant

Question 5

non-scarring alopecia

Answer 5

intact hair follicles onexam

Question 6

scarring

Answer 6

absent hair follicle on exam

Question 7

DDX of non scarring alopecia

Answer 7

autoimmune- alopecia areta
endocrine: hypothyriodism, androgens
micronutrient: zinc, iron
toxins, heavy metal, anticoagulants, chemotherapy, vitamin a
trauma to hair follicle: trichotillomania
other: symphills, severeillness, childbirth

Question 8

telogen effluvium

Answer 8

uniform decrease in hair density secondary to hairs leaving the growth (anagen) stage and entering the resting (telogen) stage of the cycle

Question 9

pathophysyiology of telgen effluvium

Answer 9

precipitated by: malnutrition, Fe deficiency, thyroid dysfunction, post-partum/miscarriage, scalp diseases (seborrheic dermatitis, allergic contact dermatitis), medications (e.g. OCP), physical/mental stress • hair loss typically occurs 2-4 mo after exposure to precipitant • regrowth occurs within a few months but may not be complete

Question 10

ANAGEN EFFLUVIUM

Answer 10

hair loss due to insult to hair follicle impairing its mitotic activity (growth stage)

Question 11

causes of anagen effluvium

Answer 11

• precipated by chemotherapeutic agents (most common), other meds (bismuth, levodopa, colchicine, cyclosporine), exposure to chemicals (thallium, boron, arsenic)
• dose-dependent effect
• hair loss 7-14 d after single pulse of chemotherapy; most clinically apparent after 1-2 mo
• reversible effect; follicles resume normal mitotic activity few weeks after agent stopped

Question 12

ALOPECIA AREATA

Answer 12

autoimmune disorder characterized by patches of complete hair loss often localized to scalp but can affect eyebrows, beard, eyelashes, etc.

Question 13

what other changes can be seen in alopecia areata

Answer 13

dystrophihc nails, exclamation mark pattents

Question 14

alopeci areata is seen in what other dieseases

Answer 14

pernicious anaemia. vitilifgo, thyroid disease, addision’s disease

Question 15

subtypes of alopecia areata

Answer 15

alopecia totalis: loss of scalp hair and eyebrow

alopecia universalis: loss of all body hair

Question 16

causes of scarring alopecia

Answer 16

• physical: radiation, burns
• infections: fungal, bacterial, TB, leprosy, viral (HZV)
• inflammatory ƒ lichen planus (lichen planopilaris) ƒ DLE (note that SLE can cause an alopecia unrelated to discoid lupus lesions which are nonscarring) ƒ morphea: “coup de sabre” with involvement of centre of scalp ƒ central centrifugal cicatricial alopecia: seen in up to 40% of black women, starting at central scalp; one of most commonly diagnosed scarring alopecias, may be associated with hair care practices in this population