DD-Dermal Structures & Diseases

Question 1

The dermis is a tough but elastic support structure that lies beneath the _______ and
above the subcutaneous tissuE

Answer 1

epidermis

Question 2

The dermis contains blood vessels, nerves, and _________ (hairs, sweat glands/ducts, etc.)

Answer 2

cutaneous appendages

Question 3

The dermis ranges in thickness from about ___mm

Answer 3

1-4 mm

Question 4

The epidermis contains _________ blood vessels

Answer 4

NO

depends on dermis

Question 5

The dermis may be further subdivided into two zones:

Answer 5

a) the papillary dermis (located immediately beneath the epidermis)

b) the reticular dermis located
deeper in the tissue.

Question 6

term often used to describe the admixture of collagen fibers, elastic fibers and ground substance all of which are synthesized by dermal fibroblasts.

Answer 6

Dermal matrix

Question 7

Three “Building Blocks”

of the Dermis

Answer 7

1. Collagen – forms the tensile strength
2. Elastic fibers – allow for resilience
3. Ground substance – facilitates diffusion

Question 8

Dermis collagen

Answer 8

Collagen 1 = >85 wt.% of adult dermis

Question 9

Vitamin____required co-factor in collagenn synthesis

Answer 9

Vitamin C

Question 10

Essentials of Collagen

Production

Answer 10

Procollagen (from fibroblasts)

• -> cleaved into TROPOcollagen
• -> linked by Vit. C

Question 11

–keratotic plugging of hairs
– perifollicular hemorrhage
– “corkscrew” hairs
– hemorrhagic gingivitis

These finding indicate?

Answer 11

Scurvy

Question 12

Lack of collagen support for ______ leads to rupture & hemorrhage (same for gums)!

Answer 12

blood vessels

Question 13

• A family of disorders based upon poor collagen synthesis

* Mutations at various stages of collagen

Answer 13

Ehlers-Danlos Syndrome

Question 14

An Acquired Disorder of Elastic Fibers

Answer 14

Solar Elastosis

Question 15

• Caused by a mutation in MDR gene

* Net result - calcified, brittle elastic fibers

Answer 15

Pseudoxanthoma Elasticum

Question 16

– hyperextensible skin
– hyperextensible joints
– fragile blood vessels
– poor wound healing

are symptoms of?

Answer 16

Ehlers-Danlos Syndrome

Question 17

– “plucked chicken” skin
– systemic hypertenision
– angioid streaks in the retina
– arterial rupture
(particularly in the eye)

Answer 17

Pseudoxanthoma Elasticum

Question 18

• Minor constituent of dermis, provides resiliency
• Thin fibers (1-3 um)
• Intertwined among collagen bundles
• Special stains are required to visualize (VVG)

Answer 18

Elastic Fibers

Question 19

• Protein-sugar moieties
– absorb 10,000x their weight in h2o:
– hyaluronic acid
– dermatan sulphate
• “Glued” together with fibronectins

• Gelatinous mass that functions as a sponge- makes diffusion possible

Answer 19

Ground Substance

Question 20

Cosmetic hyaluronic acid filler may represent an acquired

disorder of _________

Answer 20

ground substance

Question 21

• Skin vessels considered as two plexi:

Answer 21

– superficial plexus

– deep plexus

Question 22

Psoriasis and verruca share what pathology?

Answer 22

Disorders of Capillary Loops

Question 23

“Palpable purpura” - combination of inflammation and _________

Answer 23

hemorrhage

Question 24

Two Important Types of Nerve

Fibers to Be Aware Of

Answer 24

Type A and Type C

Question 25

unmyelinated, slow-conducting dermis nerve

Answer 25

Type C

Temp/Itch control

Question 26

heavily myelinated, conduct rapidly

Answer 26

Type A

Question 27

“Palpable purpura” - combination of ________ and hemorrhage

Answer 27

inflammation

Question 28

Pruritus

Answer 28

Itch

Question 29

4 things that can trigger itch:

Answer 29

– dry skin (xerosis)
– infection (HIV)
– infestation (scabies or lice)
– metabolic disorders (renal failure)

Question 30

Meissner’s Corpuscles

Answer 30

control fine touch in skin

Question 31

Pacinian Corpuscles

Answer 31

deep pressure and vibration (common in genitals)

Question 32

2 Types of hair:

Answer 32

Terminal Hairs- scalp

Vellushair- thin/ no color (ears)

Question 33

Androgenic (Androgenetic) Hair Loss

Answer 33

AKA “pattern baldness”
• Characteristic loss
• 50% of population
• Conversion of testosterone to DHT
• Results in miniaturization of follicle

Question 34

Lubricate thick terminal hairs

Answer 34

Sebaceous Glands

Question 35

abnormal follicular maturation

plugged follicular environment allows overgrowth of P. acnes

later events yield dermal inflammation

Answer 35

Acne

Question 36

• Odorless, watery sweat
• VITAL to thermoregulation
• Merocrine secretion
• Sympathetic innervation
• utilizes acetylcholine
• NOT derived from the PEG

Answer 36

Eccrine Glands

“sweat” glands

Question 37

miliaria is not

Answer 37

it is miliaria

it IS NOT malaria

Question 38

What is miliaria

Answer 38

prickly heat
Blocked sweat ducts
Manifestations depend upon site of blockage

Question 39

Outgrowths of the upper bulge of PEG
• Located in axillary and anogenital area
• Small and nonfunctional until puberty
sweat is “stickier” (sialomucin)

Answer 39

Apocrine Glands

Question 40

Hybrid sweat glands
• Located mainly in axilla
• Likely play a role in axillary hyperhidrosis
• high volume, thick product

Answer 40

Apoeccrine Glands