Chapter 19 - Skin Flashcards
What type of cells secrete melanin and filter UV light?
melanocytes
outer most layer of skin that contains keratin
epidermis
middle layer of skin that contain glands, blood vessels, and receptors
dermis
deepest later of skin that has oil glands, hair follicles, and a layer of fat?
hypodermis
bottom layer of the epidermis that has the cells that weather proof the skin? (keratinocytes)
stratum basale
what is the turnover of the epidermis layer of skin?
28 days
what is pruritis?
itchy skin
what is exanthem?
rash
what virus causes chickenpox and shingles
varicella zoster virus
symptoms of chickenpox/shingles
painful vesicles on skin
what is the main cause of warts?
100 different strains of HPV
are warts contagious?
yes - via direct contact
what is impetigo
bacterial lesion of skin that is fluid-filled and itchy
main cause of impetigo
bacteria - streptococci or staphylococcus
treatment for impetigo
antibiotics
predisposing factors of impetigo
stress in the host
dermatophytosis
fungal infection of skin, nails, and hair in which the fungus eats the keratin
where is dermatophytosis located? (which layer of skin?)
epidermis
tinea corporis
ringworm (fungal infection)
tinea capitis
fungal infection on head
tinea unguium
fungal infection of nails (thick, soft, discolored)
tinea pedis
athlete’s feet (fungal infection)
signs/symptoms of tinea
red, raised, scaly, itchy lesions on skin
is tinea contagious?
yes - thrives in warm, moist areas and injured skin is more vulnerable
what is acne characterized by the presence of?
comedones (blackheads and whiteheads)
cause of acne
hair follicles and gland ducts plugged with lipids and keratin (oil)
Bacteria then enters
Ruptures
Inflammation
treatment for acne
topical/oral antibiotics
topical/oral retinoids (vitamin A)
corticosteroids
dermatitis
inflammation of dermis
4 causes of dermatitis
-atopic (allergy - eczema)
-contact (poison ivy)
-seborrheic (sebaceous glands)
-psoriasis (dysfunctional immune system)
atopic dermatitis is also known as?
eczema
what is eczema most influenced by?
environmental factors
eczema is most common in people have other manifestations of?
atopy (allergy)
will eczema spread?
no - but does come with severe itching
psoriasis
chronic inflammatory disease where immune system isn’t functioning right
psoriasis is characterized by?
thick areas of skin with silver-colored scales
treatment for psoriasis
anti-inflammatory ointment
UVB light
immunosuppressants
vitiligo
patches of area with zero melanin
albinism
absolutely no melanin in body, no pigment
freckle
increased sensitivity of melanocytes
lentigo
hyperplasia (increase number) of melanocytes in an area that causes hyperpigmentation
melanocytic nevi
moles (benign tumors of melanocytes)
what are moles causes by?
benign proliferation of melanocytes
can moles become malignant?
yes but most are harmless
ABCDE
asymmetry
border
color
diameter
evolving
what is the most common type of skin cancer?
basal cell carcinoma
what is the most dangerous, but less common type of skin cancer?
melanoma
main risk factor for basal cell carcinoma?
sun exposure
if a basal cell carcinoma is allowed to grow it can..
interfere with function (affect nerves)
what is a neoplasm of melanocytes?
melanoma
why is melanoma so dangerous?
it metastasizes early and doesn’t respond well to chemotherapy
melanoma is more common with …
blistering sunburns compared to cumulative exposures
is melanoma only in the skin?
no, it can be other areas like the eye
alopecia
abnormal hair loss
alopecia areata
autoimmune disease resulting in patchy hair loss
senescent alopecia
hair loss due to old age
androgenetic alopecia
male pattern baldness from hormones or genetic predisposition
photoaging
changes in skin over time
what is photoaging characterized by?
wrinkles, sagging, telangiectasia, rough texture, and irregular hyperpigmentation
main cause of extrinsic/photoaging?
ultraviolet radiation
two types of UVR
UVA and UVB
what layer does UVA light penetrate to?
dermis (2nd layer) – also promotes photoaging and tanning
what layer does UVB light penetrate to?
epidermis (usually from sunburn - promotes photocarcinogenesis)
the majority of skin-related changes are due to alterations in which layer of skin?
dermis
etiology of age-related changed in skin (3)
-decrease # and function of fibroblasts
-degradation of elastin and collagen
-decreased density of cells and blood vessels
1st degree burn
damages to epidermis (light sunburn)
2nd degree burn
damage to dermis (severe sunburn and chemical burn)
3rd degree burn
damage to hypodermis (severe burns, but least painful)
skin loss/damage results in –
fluid loss and infection (requires care in burn unit)
