Pathophysiology: Chapter 47: Structure, Function, and Disorders of the Integument

Question 1

Which component of the epidermis initiates immune responses and provides a defense
against environmental antigens?
a. Langerhans cells 
b. Merkel cells 
c. Keratinocytes
d. Melanocytes

Answer 1

ANS: A
Langerhans cells (a type of dendritic cell) and dermal dendritic cells initiate an immune
response by presenting processed antigen to T cells, thus providing a defense against
environmental antigens. This function is not true of the other options.

Question 2

Which cells of the dermis release histamine and play a role in the hypersensitivity
reactions of the skin?
a. Histiocytes c. Mast cells
b. Fibroblasts d. Macrophages

Answer 2

ANS: C

Only mast cells release histamine and play a role in hypersensitivity reactions in the skin.

Question 3

Which cells of the dermis secrete connective tissue matrix?

a. Macrophages c. Fibroblasts
b. Mast cells d. Histiocytes

Answer 3

ANS: C

Only fibroblasts secrete the connective tissue matrix and collagen.

Question 4

Which gland releases secretions that are important in thermoregulation and cooling of the
body through evaporation?
a. Sebaceous c. Eccrine
b. Apocrine d. Exocrine

Answer 4

ANS: C
The eccrine sweat glands are distributed over the body, with the greatest numbers in the
palms of the hands, soles of the feet, and forehead. These secretions are important in
thermoregulation and cooling of the body through evaporation. This function is not true
for the other options.

Question 5

Which receptors of the sympathetic nervous system regulate heat loss through the skin?

a. Cholinergic c. Alpha-Adrenergic
b. ß-Adrenergic d. Anticholinergic

Answer 5

ANS: C
Heat loss can be regulated by varying blood flow through the skin by opening and closing
the arteriovenous anastomoses in conjunction with evaporative heat loss of sweat. The
sympathetic nervous system regulates vasoconstriction and vasodilation through
Alpha-adrenergic receptors only.

Question 6

What is the first change in the skin that indicates a pressure ulcer?

a. Blanchable erythema of intact skin
b. Nonblanchable erythema of intact skin
c. Blister at the site of pressure
d. Reddish-purple discoloration

Answer 6

ANS: B
Nonblanchable erythema of intact skin, usually over bony prominences, characterizes
stage 1 pressure ulcers. This selection is the only option that accurately identifies the initial
skin change indicative of a pressure ulcer.

Question 7

Which type of dressings should be applied to pressure ulcers?

a. Flat and dry c. Bulky and dry
b. Flat and moist d. Bulky and moist

Answer 7

ANS: B
Superficial pressure ulcers should be covered with flat, nonbulky dressings that cannot
wrinkle or cause increased pressure or friction. Spontaneous healing will occur more
quickly if the ulcer is kept moist with an occlusive dressing.

Question 8

What term is used to identify skin lesions that are elevated, rounded, and firm with
irregular clawlike margins that extend beyond the original site of injury?
a. Psoriasis c. Acne
b. Dermatitis d. Keloid

Answer 8

ANS: D

Of the options available, only keloids typically send out clawlike prolongations.

Question 9

Keloids are sharply elevated, irregularly shaped, progressively enlarging scars caused by
excessive amounts of which substance in the corneum during connective tissue repair?
a. Elastin c. Stroma
b. Collagen d. Reticular fibers

Answer 9

ANS: B
Abnormal wound healing with excessive fibroblast activity and collagen formation during
dermal connective tissue repair cause keloids. The other options are not associated with
keloid formation.

Question 10

In allergic contact dermatitis, which cells possess the antigens and present them to T cells?

a. Langerhans cells c. Keratinocytes
b. Merkel cells d. Macrophages

Answer 10

ANS: A
In allergic contact dermatitis, only Langerhans cells process the antigen and carry it to T
cells that then become sensitized to the antigen-releasing cytokines and chemokines,
leading to leukocyte infiltration and inflammation.

Question 11

In latex allergies, which immunoglobulin (Ig) is associated with an immediate reaction?

a. IgA c. IgG
b. IgE d. IgM

Answer 11

ANS: B
Latex allergy can be either a type IV hypersensitivity to chemicals used in latex rubber
processing or a type I immediate hypersensitivity, with IgE antibodies formed in response
to latex rubber protein. This selection is the only correct option available.

Question 12

What medical term is used to identify an inflammatory disorder of the skin that is often
considered synonymous with dermatitis and characterized by pruritus with lesions that
have an indistinct border?

a. Eczema c. Atopic dermatitis
b. Psorisis d. Pityriasis rosea

Answer 12

ANS: A
The most common inflammatory disorder of the skin is eczema, or dermatitis. Eczema and
dermatitis are general terms that describe a particular type of inflammatory response in the
skin—these terms can be used interchangeably. Pruritus, lesions with indistinct borders,
and epidermal changes generally characterize diseases that are considered eczematous. Of
the available options, only eczema is associated with these characteristics.

Question 13

What clinical manifestations do allergic contact and stasis dermatitis have in common?

a. Petechiae and hyperpigmentation
b. Edema and vesicular lesions
c. Scaling and crusting of lesions
d. Erythema and pruritus

Answer 13

ANS: D

Only erythema and pruritus are exhibited with both conditions.

Question 14

Lesions on the elbows and knees that are well demarcated, thick, silvery, scaly, and
erythematous characterize which type of psoriasis?
a. Plaque c. Guttate
b. Inverse d. Erythrodermic

Answer 14

ANS: A
The description provided is characteristic of only lesions observed in plaque psoriasis.
These lesions are well-demarcated, thick, silvery, scaly, erythematous plaque surrounded
by normal skin.

Question 15

Which skin disorder begins with a single lesion that is circular, demarcated, and salmon
pink, measures approximately 3 to 4 cm in diameter, and is usually located on the trunk?
a. Lichen planus c. Psoriasis
b. Pityriasis rosea d. Acne rosacea

Answer 15

ANS: B
Of the options available, only pityriasis rosea begins as a single lesion known as a herald
patch. This lesion is circular, demarcated, and salmon pink; it measures approximately 3 to
4 cm in diameter and is usually located on the trunk.

Question 16

Which immunoglobulin is found in skin biopsy with immunofluorescent observation of
people with discoid lupus erythematosus?
a. Immunoglobulin A (IgA) 
b. Immunoglobulin E (IgE)
c. Immunoglobulin G (IgG) 
d. Immunoglobulin M (IgM)

Answer 16

ANS: D
Skin biopsy with immunofluorescent observation reveals lumpy deposits of
immunoglobulins, especially IgM, in some individuals. This immunoglobulin is the only
one associated with discoid lupus erythematosus.

Question 17

Which term is used to identify a collection of infected hair follicles occurring most often
on the back of the neck, the upper back, and the lateral thighs that forms a mass and
evolves into an erythematous, painful, and edematous mass and drains through many
openings?
a. Erysipelas c. Carbuncles
b. Furuncles d. Boils

Answer 17

ANS: C
The term, carbuncle, is used to identify a collection of infected hair follicles occurring
most often on the back of the neck, the upper back, and the lateral thighs. The lesion
begins in the subcutaneous tissue and lower dermis as a firm mass that evolves into an
erythematous, painful, and swollen mass and drains through many openings.

Question 18

Chickenpox (varicella) may be followed years later by which disorder?

a. Erysipelas c. Warts (Verrucae)
b. Cytomegalovirus d. Herpes zoster

Answer 18

ANS: D
The same herpesvirus—varicella zoster virus (VZV)—causes both herpes zoster (shingles)
and varicella (chickenpox). Varicella is the primary infection, followed years later by
herpes zoster, particularly among those who are immunosuppressed. These statements are
not true of any of the other options.

Question 19

What type of skin infection is tinea corporis (ringworm)?

a. Nematode c. Viral
b. Fungal d. Bacterial

Answer 19

ANS: B
Tinea corporis is a fungal infection of the skin. This selection is the only option that
accurately identifies the nature of the infection.

Question 20

Cutaneous vasculitis develops from the deposit of _________________.

a. Immune complexes
b. Immunoglobulin E (IgE)
c. Complement proteins
d. T lymphocytes

Answer 20

ANS: A
Cutaneous vasculitis involves the deposit of immune complexes, initiating an uncontrolled
inflammatory response and causing the lesions that are often polymorphic.

Question 21

Which skin lesion is mediated by the immunoglobulin E (IgE)–stimulated release of
histamine, bradykinin, or kallikrein from mast cells?
a. Dermatitis c. Urticaria
b. Scleroderma d. Cutaneous vasculitis

Answer 21

ANS: C
Only urticaria is mediated by the IgE-stimulated release of histamine, bradykinin, or
kallikrein from mast cells or basophils, or both, which causes the endothelial cells of skin
blood vessels to contract.

Question 22

Scleroderma is associated with _________________.

a. X-linked recessive gene c. Virus
b. X-linked dominant gene d. Autoantibodies

Answer 22

ANS: D
Scleroderma means sclerosis of the skin and is associated with immune dysregulation and
several autoantibodies. This selection is the only option associated with scleroderma.

Question 23

What name is given to a benign proliferation of basal cells that produces smooth or warty
elevated lesions on the chest, back, and face that are tan or waxy, yellow, flesh-colored, or
dark brown to black?

a. Basal keratosis c. Keratoacanthoma
b. Seborrheic keratosis d. Actinic keratosis

Answer 23

ANS: B
Seborrheic keratosis is a benign proliferation of cutaneous basal cells that produces
smooth or warty elevated lesions. The pathogenetic origin is unknown. Seborrheic
keratosis usually occurs in older people as multiple lesions on the chest, back, and face.
The color varies from tan to waxy, yellow, flesh-colored, or dark brown to black. No other
option exhibits these characteristics.

Question 24

Lesions that usually have depressed centers with rolled borders and are frequently located
on the face and neck characterize which malignancy?
a. Squamous cell carcinoma
b. Kaposi sarcoma
c. Malignant melanoma
d. Basal cell carcinoma

Answer 24

ANS: D
Of the available options, only basal cell carcinoma has depressed centers with rolled
borders. Lesions are most often observed on people who live in regions with intense
sunlight and on those areas of the skin most exposed—namely, the face and neck.

Question 25

The alteration of which gene is associated with basal cell carcinoma?

a. myc c. src
b. TP53 d. Ras

Answer 25

ANS: B
Basal cell carcinoma arises as a consequence of ultraviolet-associated mutation in only the
TP53 tumor-suppressor gene leading to the loss of keratinocyte repair functions and
apoptosis resistance of DNA-damaged cells.

Question 26

Bowen disease is a form of which type of cancer?

a. Kaposi sarcoma
b. Malignant melanoma
c. Basal cell carcinoma
d. Squamous cell carcinoma

Answer 26

ANS: D
Squamous cell carcinoma (SCC) is a tumor of the epidermis and the second most
common human cancer. Two types are characterized: (1) in situ (Bowen disease) and (2)
invasive. Bowen disease is not a form of any of the other options.

Question 27

A small (less than 1 cm) lesion with regular edges and bristlelike hairs with a color change
that can range from skin tones to light brown characterize which form of nevus?
a. Junctional c. Intradermal
b. Epidermal d. Compound

Answer 27

ANS: C
Only intradermal nevus is characterized by a small (less than 1 cm) lesion with regular
edges and bristlelike hairs with a color change that can range from skin tones to light
brown.

Question 28

Which cell is thought to be the progenitor cell of Kaposi sarcoma?

a. Endothelial c. Melanocyte
b. Keratinocyte d. Exothelial

Answer 28

ANS: A
Only the endothelial cell is thought to be the progenitor of Kaposi sarcoma, but the
specific origin is elusive.

Question 29

Which intervention is included in the treatment of frostbite?

a. Applying local, dry heat
b. Rubbing or massaging the area
c. Immersing in warm water
d. Leaving the area uncovered

Answer 29

ANS: C
Immersion in a warm-water bath (40 to 42 C [104 to 107.6 F]) until frozen tissue is
thawed is the best treatment for frostbite. Rubbing or massaging the area would damage
the traumatized cells. The remaining options have no therapeutic value for frostbite.

Question 30

What is the purpose of administering ibuprofen to individuals being treated for frostbite?

a. Treating fever
b. Preventing plate aggregation
c. Reducing pain
d. Inhibiting prostaglandins

Answer 30

ANS: D
Ibuprophen is used to inhibit prostaglandins. Although ibuprofen may be administered for
the other reasons stated, those applications are not related to the treatment of frostbite.

Question 31

What is the medical term for a fungal infection of the nail plate?

a. Paronychia c. Tinea corporis
b. Onychomycosis d. Tinea capitis

Answer 31

ANS: B
Onychomycosis is the only term used to identify a fungal or dermatophyte infection of the
nail plate that occurs in 2% to 18% of the population.

Question 32

What term is used to identify an inflamed hair root?

a. Tinea c. Furuncle
b. Verruca d. Erysipelas

Answer 32

ANS: C
A furuncle, or “boil,” is used to identify an inflammation of the hair follicles (root) that
may develop from a preceding folliculitis and spread through the follicular wall into the
surrounding dermis.