Advanced Pathophysiology Exam Study Guide
Chapter 46: Structure, Function, and Disorder of the integumentary
Skin: is the largest organ and covers the entire body. Accessory structures of hair, nails,
and glands. Primary function is to protect the body. Barrier against microorganisms,
ultraviolet radiation, loss of body fluids, and the stress of mechanical forces. Regulates
body temperature. Involved in the production of vitamin D. The skin Protects, excrete
(sweet glands), and absorb.
Tinea Carporis (ringworm) is a fungal infection,= . Circular (round or oval) lesion with
erythema and scaling patches. Contact with kittens and puppies is consider a common
source of tinea corporis. Human-Human transmission.
1. Differentiate between the epidermis, dermis, and subcutaneous layers
Epidermis: Is the defensive barrier that continually renews itself
by shedding the superficial layer of stratum corneum. Is the
outmost layer of the skin. It has 3 additional types of protective
cells:
Melanocytes: located near the base of the epidermis.
Synthesize & secrete the melanin with exposure to UV light in
response to melanocyte stimulating hormone (MSH). Melanin
provides a protective shield against ultraviolet radiation and
determines skin color.
Langerhans cells: dermal dendritic cell that initiates immune
response by presenting antigen to T cells. Migrate to the dermis
from the bone marrow to provide protection against
environmental antigens.
Merkel cells: touch receptors. Associated with touch receptors and function when
stimulated by deformation of the epidermis.
Dermis: contains hair follicles, sebaceous glands, sweat glands, blood vessels, lymphatic
vessels and nerves. Composed of 3 types of connective tissue: collagen, elastin, reticulum,
& a gel-like ground substance. Cells of the dermis include: fibroblasts (secretes connective
tissue matrix), mast cells (release histamine & play a role in hypersensitivity reaction),
macrophages & hystiocytes.
Subcutaneous: consist of fat cells or adipocytes.
2. Given a case study identify the type of skin lesion presented
Primary skin lesions: Macule, papule, patch, plaque wheal, nodule tumor, vesicle, bulla,
pustule, cyst and telangiectasia.
Macule: A flat circumscribed area that is a change in the color of
the skin; less than 1 cm in diameter. Ex freckles, flat moles
(nevi), petechiae, measles, scarlet fever
Nevus is aggregation of melanocytes, begin from ages 3-5.
Always warrant being removed
Patch: a flat non palpable irregular-shaped macule more than 1cm in diameter. Ex vitiligo,
Mongolian spots, port wine stain, café-au-lait spots
, Papule: small, solid, elevated lesion,
circumcised area less than 1cm in diameter. Ex
Wart, elevated moles, lichen planus
Plaque: elevated firm and rough lesion with flat top surface greater
than 1cm in diameter. Ex Psoriasis, seborrheici and actinic keratoses
(shown in pic below)
Wheal: elevated irregular shaped area of cutaneous edema, solid,
transient variable diameter. Ex Insect bites, urticaria, allergic reaction
(hives)
Nodule: Palpable, solid, round lesion, deeper in dermis than a papule 1-2 cm in diameter.
Ex erythema nodosum, lipomas
Nodules
Vesicle: Elevated,
circumscribed that contains fluids, superficial, does
not extend into dermis, filled with serous fluid, less
than 1cm in diameter. Ex Varicella (chickenpox),
herpes zoster (shingles), herpes simplex: Bulla: is
vesicle greater than 1 cm in diameter
Pustule: elevated, superficial lesion, similar to a vesicle but filled with purulent fluid
(pus). Ex impetigo, acne
Cyst: sac that contains liquid or semisolid material such as fluid,
cells, and cell products.
Secondary skin lesions: are a result of primary lesions. Scale, lichenification, keloid,
scar, excoriation, fissure, erosion, ulcer and atrophy.
Scale: Heaped-up keratinized cells; flaky skin; irregular share;
thick or thin; dry or oily; variation in size. Abnormal shedding or
accumulation of stratum corneum in the form of the perceptible
flakes is called scaling. Psoriasis
Lichenification: thickening of the skin together
with accentuation of the skin. Results from
repeated rubbing, itching or skin irritation and
frequently develop in persons with atopic eczema.
Usually in the extremities
, Erosion: moist, circumscribed, usually depressed lesion,
resulting from loss of all or a portion of the viable epidermis. Ex.
Rupture of a vesicle or bulla or chemical injury.
Scar: when an ulceration has taken place. It develops so as to reflect a pattern of healing
characteristic of that area of skin. May be hypertrophic (keloid: excess of collagen
formation, elevated skin lesion, rounded, firm, irregular, claw like margin,
extended beyond the original site of origin) or atrophic
Ulcer: depressed lesion in which in which the epidermis and at least the
upper, papillary dermis have been destroyed. Always heal with scarring.
Stages:
I. Nonblanchable erythema of intact skin
II. Partial-thickness skin loss involving epidermis or dermis
III. Full-thickness skin loss involving damage or loss of subcutaneous tissue
IV. Full-thickness skin loss with damage to muscle, bone, or supporting structures
Unstageable if wound bed covered with eschar
Atrophy: thinning of the skin surface and loss of skin markings. Ex aged skin, striae, thin
facial skin in elderly
Crust: result when serum, blood or purulent exudates dries on the skin surface,
may be thin, delicate and fragile. Ex impetigo.
Impetigo: Honey crust sores around the nose, mouth and lips, but can be
spread to other areas of the body by fingers, clothing and towels. Is a
bacterial infection
Pathophysiology: Intact skin is usually resistant to colonization or infection by
S aureus or GABHS. Immunosuppression by medications (systemic
corticosteroids, oral retinoids, chemotherapy), systemic diseases (HIV infection,
diabetes mellitus), intravenous drug abuse, and dialysis encourages bacterial growth.
Clinical Manifestations: Classic signs and symptoms of impetigo involve red sores
that quickly rupture, ooze for a few days and then form a yellowish-brown crust.
Education: Keeping the skin clean is the best way to keep it healthy. Treat cuts,
scrapes, insect bites and other wounds right away by washing the affected areas.
Urticaria, allergic reactions: elevated irregular-shaped area of cutaneous edema; solid
& transient with a variable diameter.
3. Given a case study identify the type of dermatitis presented
Contact Dermatitis Atopic Dermatitis
Allergic contact dermatitis has nothing to do • Atopic dermatitis is a pruritic
with the "allergic antibody" but it is an immune dermatitis that occurs more
mediated skin rash at the site of contact with a commonly in individuals with
chemical allergen. either a personal or family history
An example of this type of rash would be the of "hay fever", asthma or eczema.
rash with poison ivy or the skin reaction to the • This is associated with the
nickel metal in costume jewelry in an "allergic" presence of the "allergic" antibody
Chapter 46: Structure, Function, and Disorder of the integumentary
Skin: is the largest organ and covers the entire body. Accessory structures of hair, nails,
and glands. Primary function is to protect the body. Barrier against microorganisms,
ultraviolet radiation, loss of body fluids, and the stress of mechanical forces. Regulates
body temperature. Involved in the production of vitamin D. The skin Protects, excrete
(sweet glands), and absorb.
Tinea Carporis (ringworm) is a fungal infection,= . Circular (round or oval) lesion with
erythema and scaling patches. Contact with kittens and puppies is consider a common
source of tinea corporis. Human-Human transmission.
1. Differentiate between the epidermis, dermis, and subcutaneous layers
Epidermis: Is the defensive barrier that continually renews itself
by shedding the superficial layer of stratum corneum. Is the
outmost layer of the skin. It has 3 additional types of protective
cells:
Melanocytes: located near the base of the epidermis.
Synthesize & secrete the melanin with exposure to UV light in
response to melanocyte stimulating hormone (MSH). Melanin
provides a protective shield against ultraviolet radiation and
determines skin color.
Langerhans cells: dermal dendritic cell that initiates immune
response by presenting antigen to T cells. Migrate to the dermis
from the bone marrow to provide protection against
environmental antigens.
Merkel cells: touch receptors. Associated with touch receptors and function when
stimulated by deformation of the epidermis.
Dermis: contains hair follicles, sebaceous glands, sweat glands, blood vessels, lymphatic
vessels and nerves. Composed of 3 types of connective tissue: collagen, elastin, reticulum,
& a gel-like ground substance. Cells of the dermis include: fibroblasts (secretes connective
tissue matrix), mast cells (release histamine & play a role in hypersensitivity reaction),
macrophages & hystiocytes.
Subcutaneous: consist of fat cells or adipocytes.
2. Given a case study identify the type of skin lesion presented
Primary skin lesions: Macule, papule, patch, plaque wheal, nodule tumor, vesicle, bulla,
pustule, cyst and telangiectasia.
Macule: A flat circumscribed area that is a change in the color of
the skin; less than 1 cm in diameter. Ex freckles, flat moles
(nevi), petechiae, measles, scarlet fever
Nevus is aggregation of melanocytes, begin from ages 3-5.
Always warrant being removed
Patch: a flat non palpable irregular-shaped macule more than 1cm in diameter. Ex vitiligo,
Mongolian spots, port wine stain, café-au-lait spots
, Papule: small, solid, elevated lesion,
circumcised area less than 1cm in diameter. Ex
Wart, elevated moles, lichen planus
Plaque: elevated firm and rough lesion with flat top surface greater
than 1cm in diameter. Ex Psoriasis, seborrheici and actinic keratoses
(shown in pic below)
Wheal: elevated irregular shaped area of cutaneous edema, solid,
transient variable diameter. Ex Insect bites, urticaria, allergic reaction
(hives)
Nodule: Palpable, solid, round lesion, deeper in dermis than a papule 1-2 cm in diameter.
Ex erythema nodosum, lipomas
Nodules
Vesicle: Elevated,
circumscribed that contains fluids, superficial, does
not extend into dermis, filled with serous fluid, less
than 1cm in diameter. Ex Varicella (chickenpox),
herpes zoster (shingles), herpes simplex: Bulla: is
vesicle greater than 1 cm in diameter
Pustule: elevated, superficial lesion, similar to a vesicle but filled with purulent fluid
(pus). Ex impetigo, acne
Cyst: sac that contains liquid or semisolid material such as fluid,
cells, and cell products.
Secondary skin lesions: are a result of primary lesions. Scale, lichenification, keloid,
scar, excoriation, fissure, erosion, ulcer and atrophy.
Scale: Heaped-up keratinized cells; flaky skin; irregular share;
thick or thin; dry or oily; variation in size. Abnormal shedding or
accumulation of stratum corneum in the form of the perceptible
flakes is called scaling. Psoriasis
Lichenification: thickening of the skin together
with accentuation of the skin. Results from
repeated rubbing, itching or skin irritation and
frequently develop in persons with atopic eczema.
Usually in the extremities
, Erosion: moist, circumscribed, usually depressed lesion,
resulting from loss of all or a portion of the viable epidermis. Ex.
Rupture of a vesicle or bulla or chemical injury.
Scar: when an ulceration has taken place. It develops so as to reflect a pattern of healing
characteristic of that area of skin. May be hypertrophic (keloid: excess of collagen
formation, elevated skin lesion, rounded, firm, irregular, claw like margin,
extended beyond the original site of origin) or atrophic
Ulcer: depressed lesion in which in which the epidermis and at least the
upper, papillary dermis have been destroyed. Always heal with scarring.
Stages:
I. Nonblanchable erythema of intact skin
II. Partial-thickness skin loss involving epidermis or dermis
III. Full-thickness skin loss involving damage or loss of subcutaneous tissue
IV. Full-thickness skin loss with damage to muscle, bone, or supporting structures
Unstageable if wound bed covered with eschar
Atrophy: thinning of the skin surface and loss of skin markings. Ex aged skin, striae, thin
facial skin in elderly
Crust: result when serum, blood or purulent exudates dries on the skin surface,
may be thin, delicate and fragile. Ex impetigo.
Impetigo: Honey crust sores around the nose, mouth and lips, but can be
spread to other areas of the body by fingers, clothing and towels. Is a
bacterial infection
Pathophysiology: Intact skin is usually resistant to colonization or infection by
S aureus or GABHS. Immunosuppression by medications (systemic
corticosteroids, oral retinoids, chemotherapy), systemic diseases (HIV infection,
diabetes mellitus), intravenous drug abuse, and dialysis encourages bacterial growth.
Clinical Manifestations: Classic signs and symptoms of impetigo involve red sores
that quickly rupture, ooze for a few days and then form a yellowish-brown crust.
Education: Keeping the skin clean is the best way to keep it healthy. Treat cuts,
scrapes, insect bites and other wounds right away by washing the affected areas.
Urticaria, allergic reactions: elevated irregular-shaped area of cutaneous edema; solid
& transient with a variable diameter.
3. Given a case study identify the type of dermatitis presented
Contact Dermatitis Atopic Dermatitis
Allergic contact dermatitis has nothing to do • Atopic dermatitis is a pruritic
with the "allergic antibody" but it is an immune dermatitis that occurs more
mediated skin rash at the site of contact with a commonly in individuals with
chemical allergen. either a personal or family history
An example of this type of rash would be the of "hay fever", asthma or eczema.
rash with poison ivy or the skin reaction to the • This is associated with the
nickel metal in costume jewelry in an "allergic" presence of the "allergic" antibody
