integumentary system
epidermis, dermis, and subcutaneous tissue
Skin
largest visible organ, consisting of 16% of body weight
Function of skin
1. Temperature Control
2. Barrier Protection
3. Secretion and absorption
4. Vitamin D production
5. Immunological Surveillance
6. Mirror for internal disease
7. indicator of general health
Temperature Control and Regulation (too cool)
temperature sensors send information about body temperature to the hypothalamus --> information to sweat glands and blood vessels--> sweat glands excrete sweat onto the surface of skin--> as sweat evaporates--> body cools -->blood vessels dilate and heat
Hypothalamus
temperature-regulating center in the brain
Temperature Control and Regulation (too heat up)
skin sends information to the hypothalamus to heat--> erector muscles of skin contract--> raising small hairs on skin (traps air and provides insulation that reduces heat loss)--> shivering occurs (increase metabolic rate and raise temperature)--> superfi
Barrier Protection
protect the body from injury and infection (physical, chemical, and environmental hazards)
-stratum corneum stop antigens from entering the body and keep the body waterproof
Excretion
-volume of sweat
removes water, heat, salt, carbon dioxide, ammonia, and urea from the body
Absorption
fat-soluble substances (vitamin A, D, E ,K) penetrate the skin
-oxygen, carbon dioxide and other gases
Vitamin D production
interaction of UV light with the skin is a major factor in Vitamin D synthesis
-chemical 7-dehydrocholesterol converts to cholecalciferol
Vitamin D precursor
cholecalciferol
immunological surveillance
skin surface enzymes, acids, waxy sebum, work together to repel pathogens that try to enter the body via skin
-help of keratinocytes and Langerhans's cells
Keratinocytes
surface layer epidermal cells-- regulate the immunological response and secrete inflammatory mediators
Langerhans cells
detect foreign antigens that penetrated the epidermis and present antigens to the lymphocytes that take part in the adaptive immunological response
Mirror for internal disease
Urticaria, wheals, blisters, bullae, etc., make its appearance of the skin that will show an immune response that is actively occurring below skins surface
Indicator of general health
changes in color of the skin and nail beds, etc. reflect circulation and may indicate disease
Ecchymosis
bruising
Billrubin
increase of this can change skin color and eyes to yellow
Cyanotic
Bluish skin color due to lack of Oxygen
erythema
redness of the skin
beta-carotene
an orange vegetable pigment that the body can change into the active form of vitamin a, one of the antioxidant nutrients
Assessment/physical exam of skin
-entire skin surface is examined
-lesions are visualized and palpated to determine color; size; texture; consistency; presence of scales; inflammation and edmema
Atrophy
thinning and loss of skin layers
Bulla
large blisters (0.5 cm)
Crust
dried yellowish or yellow-brown exudate on skin
Erythema
reddened skin: area balances with pressure
Excoriation
scratch that breaks skin surface
Fissure
cracks in skin that breaks through keratin
Induration
hardening or thickening of the skin
Keloid
irregular, elevated scar tissue formed by excessive collagen growth during wound healing
Lichenification:
hardening or thickening of the skin with markings; develops from repeated trauma; scratching
Macule
defined, flat area of altered pigmentation
Nodule
solid lump larger than 0.5 cm
Papule
raised, well-defined lesion, smaller 0.5 cm
Plaque
raised, flat-topped lesion, larger than 2 cm
Purpura
purplish lesion caused by free blood cells in the skin; does not blanch and may be nodular
Pustule
papule filled with pus
Scale
fragment of dry skin
Scar
permanent replacement of normal skin with connective tissue
Telangiectasia
fine, irregular, red lines produced by dilation of the capillaries
Ulcer
loss of epidermal and dermal tissue
Vesicle (blister)
blister smaller than 0.5 cm
Wheals/urticaria
transient pink, itchy, elevated papules that evolve into irregular red maculopapular patches
Albinism
genetic disorder, deprives skin, hair, eyes of pigment
-leaves person with diminished vision and extreme sensitivity to light and UV rays
-pale skin, yellow hair, very light or pink eyes
-lack pigment melanin
Vitiligo
acquired skin condition characterized by abnormalities in the production of melanin
-presents as discolored patches on the skin
-face, neck, axillae, and extremities
-depigmented, itchy, and easily burned when exposed to sun or UV rays
-cause and no treat
Melasma
-cholasma
-dark macules on the face
-more common in brown-skinned woman who use oral contraceptives
-skin damage can cause
Lentigos
Age spots
Appear on fair, sun damaged areas on the skin
-Hands, forearms, and face
Elastosis
skin aging- more prominent in sun damaged skin
Xerosis
dry skin
-caused by dehydration of stratum corneum, changes to sebaceous glands, decreased sweat and flattening of epidermal ridges, which reduce the ability of fluids to move between skin's layers
Pruritis
itching
-associated with rash or bite
-manifestation can be a sign of systemic illness, liver failure or psychogenic origin
Acanthosis nigricans
thickening and darkening of skin near axillary region, A/w Diabetes Type II and gastric carcinoma
male pattern baldness
-genetic
-occur at any age
-influenced by male hormones
-front, sides and crown of head
Female pattern baldness
less common
-entire head
hirsutism
-male pattern growth, seen in women with increased androgenic hormones
Alopecia Areata
-Sudden loss of hair in one area
-Can be caused by scalp ringworm
Chemo radiation
can result to hair loss
-after cessation of treatment hair usually returns
Clubbed fingernails
Exhibit Schamroth sign: obliteration of the diamond shape space at the proximal end of the nail when the distal phalangeal bones are opposed
Pitting
-associated with psoriasis
-caused by chronic illnesses
-shallow or deep holes
Beau's lines
Visible depressions running across the width of the natural nail plate
-due to chronic illness
-trauma or Raynaud's syndrome
Koilonchyia
Spooning of nails
-Thyroid or liver disorders
-Cardiovascular disease or iron deficiency
Paronychia
fold seal between nail plate and surrounding tissue is broken, bacteria and fungi can invade the tissue
-Pain, erythema, and swelling
-Abscess is commonly present
s. aureas
Main cause of nail diseases
Bacterial (s. aureaus) or fungal infections (canida)
Onychomycosis
Term for fungal or yeast infection that involves the proximal and lateral nail folds
-Discoloration of the nail; darker--degree of discoloration dictates depth of the infection
onycholysis
Invasion may be deep enough to cause nail plate to separate from nailbed
Hyperhidrosis
Excessive sweat production
-Palms, soles, axilla
Trauma, physiological, pathological, or endocrine factors
-febrile disease, hyperthyroidism and diabetes
Anhidrosis
Decreased sweat production
-Head injuries, tumors, occlusions of the sweat ducts, degeneration of peripheral sympathetic fibers, atrophy caused by burns or radiotherapy, and use of anticholinergic drugs
-not uncommon for babies
Hidradenitis suppurativa
Disorder of apocrine sweat glands (axilla and groin)
-Plugging or clogging of gland opening onto skin
-Obesity and poor hygiene (causes) will make glandular swelling worse
Disorders of Sweat Glands
Hyperhidrosis
Anhidrosis
Hidradenitis suppurativa
Disorders of Nails
-Clubbed Fingernails
-Pitting/ Beau's lines
-Koilonychia
-Paronychia
Onychomycosis
Disorders of Sebaceous Glands
-Acne vulgaris
-Comedones
-Acne rosacea
Acne vulgaris
-common multifactored inflammatory disorder
-Lesions are inflammatory papules, pustules, nodules, noninflammatory open or closed comedones and cysts
-Common on exposed areas: face, back and chest
Follicle open
black head
Follicle Closed
white head
Acne rosacea
-middle-aged adults: appears as erythematous papules and pustules
-Occurs usually with inappropriate vasodilation, appear in middle thirds of the face but may extend to forehead and chin
-Inflammatory process affects the nose, it produces unsightly, irrev
Disorders of the hair
-Male and Female Pattern Baldness
-Alopecia Areata
-chemo/radiation
-Hirsutism
Disorder of the skin
Elastosis
xerosis
Pruritus
Acanthosis nigricans
Disorders of skin color
-albinism
-vitiligo
-melasma
-lentigos
Hemangiomas
-benign tumors of blood vessels
-develop at birth or infancy
birthmark and developmental conditions affecting the skin
Hemangioma
-spider vein
-portwine stains
-strawberry hemangioma
-mongolian spot
portwine stain
permanent blood vessel abnormalities
-affecting 0.5%
-at birth pink patches
-ages, birthmark darkens and becomes larger
strawberry hemangioma
enlarged blood vessels that grow rapidly after birth and resolve by 6 years of age
spider veins
enlarged blood vessels that grow with age
magnolian spot
benign darkened area of skin commonly on back of buttocks
-Nevi
-Actinic Keratosis
-Lentigos
precancerous skin lesions
actinic keratosis
a precancerous skin growth that occurs on sun-damaged skin
-present as scaly, patchy, rough and red plaques
Lentigos
premalignant skin lesion, usually appear as brown spots on sun-exposed areas
Nevi
moles
-most common benign skin lesion
-present as papules and nodules and vary in size
should be periodically asses as these can undergo cancerous changes
premalignant skin lesions
Melignant melanoma
a. The most aggressive & life-threatening form of skin cancer
b. Develops in the melanocytes, and spreads quickly.
c. Usually flat or slightly raised in appearance (black or brown, but can be pink, red, purple blue, white)
d. Cure rates depend upon time o
Three types of skin cancer
basal cell carcinoma, squamous cell carcinoma, melanoma
any change in size, color, border or appearance of nevus can indicate
malignant melanoma
dysplastic nevus can be considered a
premalignant stage of melanoma
-Any change in size, color, border, or appearance of a nevus can indicate malignant melanoma.
Most common type of cancer
skin cancer
Stage 0 of Melanoma
melanoma is confined to the epidermis (top layer of skin)
Stage 1-2 of Melanoma
melanoma is confined to the skin, but has increasing thickness and the skin may be intact or ulcerated (top layer of skin is absent)
Stage 3 melanoma
has spread to nearby lymph node and is found in increasing amounts within one or more lymph nodes
Stage 4 melanoma
spread to internal organs, beyond the closest lymph nodes to other lymph nodes, or areas of skin far from original tumor
ABCDE Characteristics of Malignant Melanoma
A: Asymmetry: one half that is unlike the other
B: Border: an irregular, scalloped, or poorly defined border
C: Color: varied from one area to another; shades of tan, brown, and black; sometimes white, red, or blue
D: Diameter: usually greater than 6 mm,
Change in a mole
common warning sign of melanoma
-shape, color, diameter
-mole becomes painful or begins to bleed or itch
basal cell carcinoma
most common form of skin cancer
-rarely metastasize to other parts of the body
-can grow deeply and invade surrounding tissue
-most common on face
-main cause: UV radiation from the sun
-most typical age: after 50
squamous cell carcinoma
most common cause by UV rays
-increase with age
-damage accumulates, increasing risk
-signs/symptoms: red crusted scaly patch of skin
-nonhealing ulcer or firm red nodule
two types of fungi
mold and yeast
yeast
Candida albicans
-single celled fungus
Dermatophytes (tinea, ringworm)
superficial fungi
-live on keratinized tissue of skin, hair and nails and secrete digestive enzymes that cause skin scaling, nail disintegration, and broken hair
Viral Skin disease
Verrucae (warts)
plantar warts
genital warts
Verrucae (warts)
benign lesions of the skin caused by the HPV
Warts are caused by
HPV; transmitted by touch
-round, rough, and gray-colored lesions that can occur anywhere in the body
genital warts (condylomata acuminata)
HPV- target mucous membrane of the external genitalia and anus
HPV infection can cause
cervical, anal, or oropharyngeal cancers or resolve without consequences
Herpes Simplex Virus (HSV)
HSV-1 (above the waist)
HSV-2 (below the waist)
-remains dormant in neurons
-can be activated by stress
HSV symptoms
Tingling/Itching sensation episodic multiple painful vesicular eruptions (blisterlike rash)
Varicella-Zoster Virus (VZV)
1. causes chickenpox-- and herpes zoster (shingles)
Lesions>macule >vesicle> crusts over Herpes Zoster
-remains dormant>reactivates as shingles in adults
Arachnid Bites
mites, ticks, and spiders
-can cause different skin disorders
Scabies
-mite bites
-associated with malnutrition, poverty, and sexual promiscuity
-skin to skin contact
Tick Bites
spirochete bacteria, Borrelia burgdorferi
-deer and squirrels
-forested areas
-ticks>bite humans > cause Borrelia infection >lyme disease
Spider Bites
-common
symptoms: pain, redness, itching, swelling, small puncture wounds
Bed bugs
Cimex lectularius
-lack of clean mattresses or bedding
-homeless people at greater risk
-itchy skin
-red wheals arranged in linear patterns
Pediculosis
Lice
-associated with lack of cleanliness
-Lice attach to skin, biting and sucking blood. -They can live on clothing for up to a month
Symptoms of Pediculosis
-produce reddened macules, inflammation, hyperpigmentation, and parallel scratch marks
Pediculosis Pubis
pubic lice infestation
Treatment of Lice
finding the lice or lice eggs, called nits, in the clothing, bed linen, or the hair of the person who has been bitten
-requires the destruction of lice with special soaps, shampoos, and rinses.
-Fine combs are used to determine if there are nits in hairy
Mosquito bite
-Malaria
-zika virus
Symptom of spider bites
local itching
rash and burning
systemic symptoms: sweating, nausea, and vomiting
Hymenoptera Bites and Stings
bees, wasps, and fleas
-local inflammation
-irritation, swelling and itching
-can cause anaphylaxis
-
Bee and wasp stings
painful and swelling and itching persist for about week
-treatment: removal of stinger, ice the area
Pulicosis
flea bites
-small brown lesions
-hemorrhagic puncture surrounded by red, urticarial patch
-zigzag pattern
-waist and legs
-often found in sets of three
Decubitus Ulcers
Pressure ulcers
-bed sores
-most common in skin ulcers
-produce blisters, followed by a reddish-blue discoloration, and finally skin breakdown and tissue ulceration which created opportunities for infection
-prevention: change of position and range of mot
Stasis Ulcers
Affect the lower legs and feet and are caused by poor blood return through the veins
Risk factors:
-obesity
-pregnancy
-family history
-old age
-blood clotting
-valves in legs become blocked, blood flow back to the heart is compromised
-as pressure rises,
Tattooing
- if tools and environment are not sanitary, infection, hepatitis B, C or HIV can be transmitted
-MRSA
-develop granulomas and contract dermatitis
-tattoo removal is used by lasers to break down the tattoo
Pattern of injuries
injuries, usually bruises and fractures, in various stages of healing
-indicate physical abuse
-history of injury is not consistent with its appearance and severity
-report to authority
Atopic Dermatitis
eczema
-most common dermatitis
infantile
-vesicle formation, oozing, crusting with excoriation that begins on the cheeks and spreads to scalp, arms, trunk, and legs
adult
-dry, linchenified lesions that are either hypopigmented or hyperpigmented
(antecubi
Contact Dermatitis
dermatitis-represents delayed hypersensitivity to materials such as metals, chemicals, drugs, and poison ivy
-An allergic skin reaction that usually occurs days after the skin contact with the allergen
seborrheic dermatitis
inflammation of the skin caused by excessive secretions of the sebaceous glands
-Lesions are red, usually on the face and scalp, and yield yellow to yellow-brown scales, or dandruff
Lesions appear - greasy, inflamed, and itchy
Psoriasis
genetic, chronic thickening of the epidermis that presents as overlying silver-white scales covering red, circumscribed, thickened plaques
Psoriasis pathophysiology
T-cell mediated autoimmune disorder to unknown antigen
Acute Urticaria
hives
-elevated, pink or red, itchy blotches or plaques varying in size
-wheals, appear suddenly on the skin and blanch with pressure
-accompanied with angiodema
Angiodema
swelling around the face
Cause of Acute Urticaria
release of histamines from the granules of mast cells
Chronic Urticaria
an autoimmune disorder, but extensive laboratory workups usually fail to identify a causal agent
-It may manifest an underlying disease, certain cancers, collagen diseases, or hepatitis B
scleroderma
autoimmune disorder
-systemic disease
-occurs mostly in woman
-affects connective tissue and blood vessels
-alters skins appearance and flexibility and restricts movement
-affects internal organs and cause cardia problems
lupus erythematosus
can be systemic or localized
discoid lupus erythematosus
DLE
-skin disease
-middle aged woman
-appearing on exposed areas of the skin
-seen on face
-red, plaque like, asymmetric, butterfly-pattern lesion over the nose and cheeks
-skin biopsy reveal excess IgM
-random hair loss
-urticaria and Raynaud's phenomeno
systemic lupus erythematosus
SLE
-multisystem autoimmune disease characterized by autoantibodies, particularly antinuclear antibodies (ANA's)
-chronic disease
-fever, skin rash, joint inflammation, and damage to the kidney's lungs, and serosal membranes
Etiology/Risk Factors of SLE
Genetic predisposition ad environmental, hormonal, and immunological elements
-chromosomes 1 and 6 most documented linkage
-Epstein Barr Virus (EBV) increase risk
-African Americans
-UV makes it worse
-estrogen linked
-during menses or pregnancy
Pathophysiology of SLE
Antinuclear antibodies (ANAs) affect DNA, RNA within the cell nuclei
Form complexes in connective tissue of blood vessels, lymphatic vessels and other tissues, complement is activated
Trigger inflammatory response and tissue damage
Target areas are kidney
Raynaud's phenomenon
common with SLE:
a peripheral arterial occlusive disease in which intermittent attacks are triggered by cold or stress
Erythema multiforme
acute hypersensitivity disorder of the skin and muscous membranes that is associated with allergic or toxin reactions to drugs or microorganisms
-HSV most common
Ebstein-Barr virus, HIV, Hepatitis C, and Coxsackie
trigger EM
Pathophysiology of Erythema Multiforme
immune complex formation and deposits of complement C3, IgM, and fibrinogen develop around superficial dermal vessels, basement membranes, and keratinocytes
Symptoms of Erythema Multforme
no prenominal symptoms
-rash of sharply demarcated pruritic, red and pink macules appear
-macules evolved to papules then to large red plaques
Steven-Johnson Syndrome
toxic epidermal necrolysis
-genetic predisposition HLA-B1502
-rare and serious disorder of the skin and mucous membranes usually triggered by infection or drug
-HIV infection
-family history
-herpes
-pneumonia
-herpes
-HIV
-hepatitis A
-bacterial skin inf
Symptoms of Stevens-Johnson Syndrome
flu-like symptoms
-fever, red, painful, red rash that evolves to blisters
-bullae and sloughing of skin
-mouth, eyes, nose and genital areas
-
Complication of Stevens-Johnson Syndrome
-toxic epidermal necrosis
-wide spread exfoliation
-respiratory failure
cellulitis
-sepsis
-shock