Pathophys - Acne

Question 1

true or false

bacteria causes acne

Answer 1

FALSE

they get trapped in the mass of skin cells and sebum, allowing growth more rapidly, but it is NOT THE PRIMARY CAUSE

primary cause is abnormal growth of skin cells and collection of sebum

bacteria get TRAPPED in these skin cells and sebum, allowing them to grow more rapidly. they’re a CONSEQUENCE, or secondary cause

Question 2

true or false

acne is chronic

Answer 2

true

Question 3

acne is a chronic skin disorder of ______ that occurs why?

Answer 3

chronic disorder of HAIR FOLLICLES

occurs due to a blockage by SKIN CELLS AND SEBUM

Question 4

acne occurs when……

Answer 4

dead skin cells and oil (sebum) from the skin clogs hair follicles

Question 5

what is a comedone?

Answer 5

a hair follicle that has been clogged by dead skin cells and sebum

Question 6

how are comedones important in the development of acne

Answer 6

they allow the excess growth of CUTIBACTERIUM ACNES – a commensal skin bacteria

this moist environment is ideal for bacteria to grow

Question 7

true or false

the commensal bacteria, cutibacterium acnes, is responsible for the formation of a comedone and the start of acne

Answer 7

FALSE

the cause is a hair follicle clogged by SKIN CELLS AND SEBUM

the bacteria gets trapped AFTER THIS CLOG

Question 8

true or false

cutibacterium acnes is a commensal bacteria

Answer 8

true

Question 9

comedones start as what and progress to what?

Answer 9

starts as microcomedones and they enlarge to form PIMPLES

Question 10

name 2 different types of pimples and why they present this way

Answer 10

whiteheads and blackheads

white heads are the result of a DEEP microcomedone that is closed

black heads are a SUPERFICIAL microcomedone that is open to air, and allows the oxidation of melanin – that’s why it has a black color

Question 11

explain how acne can cause skin scarring and pus-filled raised areas (pimples)

Answer 11

when the microcomedone gets a lot of sebum and bacteria trapped inside, the bacteria can invoke the inflammatory process – causing the formation of a pus-filled raised pimple as well as tissue damage and scarring of the skin

Question 12

what is the major risk factor for acne

Answer 12

GENETICS

Question 13

true or false

the risk of developing acne is largely inherited

Answer 13

true

Question 14

explain how acne is genetically linked

Answer 14

genetics control ANDROGEN PRODUCTION

androgens regulate the formation of sebum. if too many – too much sebum production

Question 15

______ traps _______- in _______ to form a comedone

Answer 15

sebum traps dead skin cells in hair follicles to produce a comedone

Question 16

what can cause increased sebum production

Answer 16

androgens

Question 17

true or false

acne is likely of polygenic inheritance

Answer 17

true

Question 18

acne is associated with ___ syndrome

why

Answer 18

XYY syndrome

“super male” - extra Y chromosome

there is high rate and severity of acne, as well as hair growth on the edge of the ear

Question 19

name 2 hormones that seem to be the principle drivers in acne formation

Answer 19

androgens
growth hormone

Question 20

name 2 androgens that are involved in acne formation

Answer 20

testosterone
DHT - dihydrotestosterone

Question 21

acne still develops in those with androgen insensitivity

what can you conclude from this?

Answer 21

androgens are not the lone essential cause for acne – another main cause is IGF-1 (insulin like growth factor)

Question 22

true or false

both males and females produce androgens and estrogens

Answer 22

true - just in varying amounts

Question 23

where are androgens and estrogens made

Answer 23

in the adrenal cortex

Question 24

how can increased androgens cause acne

Answer 24

they stimulate the growth of skin cells and increased production of sebum – cause hair follicle to clog and bacteria can get trapped too

Question 25

how is it that the onset of acne is typically at puberty

Answer 25

increase in hormones!! (androgens and insulin like growth factor) clogs follicles through increased sebum production and growth of skin cells

Question 26

explain the role of cutibacterium acnes in acne

Answer 26

it is COMMENSAL -- normally grows on the skin and has protective function it is ANEAROBIC - does not need oxygen to grow therefore, when trapped in sealed comedone with sebum and dead cells, it can easily grow even without oxygen

Question 27

how are mites related to the formation of acne

Answer 27

infections with mites (particularly demodex) is associated with formation of comedones and acne

Question 28

true or false some strains of c. acnes are associated with normal skin and other strains are associated with acne

Answer 28

true

Question 29

what kind of professionals often have an increased risk in formation of acne and why

Answer 29

athletes causes by the mechanical obstruction of hair follicles -- obstructed bc of the equipment they wear such as helmets

Question 30

true or false mechanical obstruction of the skin is not thought to play a role in acne

Answer 30

false - it is ie: athletes and their equipment (helmets)

Question 31

name 6 types of drugs that have been shown to worse pre existing acne what are they all associated with?

Answer 31

testosterone bromides glucocorticoids hydantoin iodides isonaizid all associated with cell growth

Question 32

the blockage of hair follicles occurs due to ___ events:

Answer 32

4 events: increased sebum production excessive deposition of keratin comedone formation colonization of the follicle by bacterium (usually C. acnes)

Question 33

what is at the heart of developing acne? what is the overarching event?

Answer 33

the 4 events that lead to the blockage of hair follicles -- increased sebum production, excessive deposition of keratin, comedone formation, colonization of follicle by c. bacterium OVERARCHING EVENT IS CHANGES IN HORMONE PRODUCTION

Question 34

what is DHEA-S

Answer 34

a hormone whose levels are increased by the adrenal glands at puberty leads to increased sebum production and growth of skin bacteria (C. acnes) and skin cells

Question 35

true or false while bacteria is NOT the cause of acne, it can enlarge the damage

Answer 35

TRUE bc it invokes the inflammatory response -- bc it binds and activates TLRs (toll like receptors) and increases secretion of cytokines like IL-1A TNFa, IL8, LTB4 also the bacteria themselves produce enzymes that can damage tissue and form scars

Question 36

as mentioned, bacteria invokes the inflammatory response and causes an increase in cytokines what are 3 results of this

Answer 36

increased skin cell production trapping of cells in the sebum excessive growth and trapping = COMEDONE FORMATION

Question 37

true or false the bacteria themselves do not cause injury, but only indirectly through invoking the inflammatory process

Answer 37

FALSE - they can cause injury by releasing enzymes themselves that damage tissue enzymes can cause phagocytes to release metalloproteases which damage tissue

Question 38

what is squalene and its role in acne development

Answer 38

a component of sebum when it is oxidized, it activates NFKB, which secretes IL-1A AND increases 5-lipooxygenase activity this leads to increase in LKB4 (leukotriene B4) --- a promoter of inflammation inflammation causes local tissue death and scarring