Dermatology

list the layers of the epidermis, from outermost to inner most:

horny cell layer

granular layer

stratum spinosum

basal layer and melanocytes

what layer of the skin are fibroblasts located?

dermis

list the characteristics of melanocytes

have dendrites

different people have the same amount of melanocytes but different amounts of melanosomes

protects the cells from UV light.

what is the average area of skin in adults?

1\.6 m^2

what is the pH of the skin?

5\.5

what are the 3 glands in the skin?

eccrine gland, apocrine gland, sebaceous gland

what is synthesized in the skin?

vitamin D and various cytokines (IL-1, 3, 6, 8, INFalpha and beta)

what cytodifferentiation is keratinization?

cytodifferentiation of bsasal cells to stratum corneum (horny cell layer)

how many layers are there of dead keratinocytes in the horny cell layer?

10

in the granular cell layer, what is the characteristic of granules in the cells?

basophilic

which layer of the epidermis has well-developed desmosomes?

spinous cell layer (stratum spinosum)

what are the 2 types of melanin and what color are they?

eumelanin (black) and phomelanin (yellow)

what stimulates melanin synthesis?

ACTH, MSH, thyroid hormone, estrogen, UV ray, X ray

what white blood cell resides in the epidermis?

langerhans cells (they migrate to lymph nodes one they are exposed to an antigen)

what cell resides in the basal cell layer and responsible for sensing stimuli?

merkel cell

what does the eccrine glands secrete?

sweat

what part of the body has the highest density of eccrine glands?

palms and soles

what are the 2 types of secretory cells in the eccrine gland?

clear cells and dark cells

where are apocrine glands found?

axillae, areola, nipples, perianal region, external genitalia.

how does apocrine secretion gain odor?

when it is secretes it is odorless, but when it reacts with the bacteria on the skin, it gains an odor.

where does the apocrine excretory duct open up to?

hair follicle

what is decapsulation secretion?

when the substance is secreted from the “head” of the cells of the secretory gland. Apocrine glands undergo decapsulation.

what are the components of a hair follicle?

sebaceous gland, arrector pili muscle, hair bulge

what are the 3 phases of the hair cycle?

anagen (growth), catagen (transition), telogen (rest)

what sensations are sensed by the Meissner’s corpuscle?

light touch

what sensations are sensed by the Ruffini corpuscle?

sense and control of finger position and movement

what sensations are sensed by the Vater-pacinian corpuscle?

vibration and pressure

what sensations are sensed by the krause’s corpuscle?

cold temperature

what type of secretion is the sebaceous gland?

holocrine secretion

what type of secretion is eccrine glands?

merocrine secretion (exocytosis and diacrine)

what are the 3 stages of wound healing?

inflammation, tissue growth, remodelling

what is a decubitus ulcer?

Decubitus ulcers occur when there is prolonged pressure on specific areas of the body that are susceptible to friction and shear force injuries.

how is a decubitus ulcer rated?

DESIGN-P (depth, exudate, size, inflammation/infection, granulation tissue, necreotic tissue, pocket)

list examples of primary lesions

erhythema, telangiectasia, wheel, purpura, macule, papule, nodule, tumor, cyst, abscess, bulla, pustule

list examples of secondary lesions

erosion, ulcer, scale, crust, etc.

what is auspitz’s sign?"

pinpoint bleeding of the skin after scratching the skin off

what diseases are auspitz’s sign positive?

psoriasis

what is darier’s sign and what condition is darier’s sign positive?

2-5 mintues after rubbing or stroking a lesion, erythema and a wheel formation occurs. A sign of mastocytosis (urticaria pigmentosa) and malignancies

list 4 diseases that are Nikolsky’s sign positive

pemphigus vulgaris

staphylococcal scalded skin syndrome

stevens-johnson syndrome

toxic epidermal necrolysis

what skin test is useful for distinguishing between erythema and purpura?

diascopy (tumbler test)

drug lymphocyte stimulation test requires a blood sample. true or false?

true

what test should be done for a patient with polymorphous light eruption?

measurement of minimal erythema dose

atopic dermatitis shows an elevation of Ig ( )

E

what is the treatment of atopic dermatitis?

topical steroids

what disease is white dermographism seen?

atopic dermatitis

what type of hypersensitivity is allergic contact dermatitis?

type 4

neutrophilic dermatosis is associated with what diseases?

rheumatoid arthritis

myelodyplastic syndrome

ulcerative colitis

what are the clinical findings of sweet syndrome?

high fever, pain, tender plaque and nodules, leukocytosis

what are the side effects of systemic steroids?

weight gain, sleep disturbances, infection, peptic ulceration, osteoporosis

what is the pathogenesis of sweet syndrome?

dermal neutrophilic infiltration

what virus is reactivated in drug-induced hyperactivity syndrome?

HPV6

what are the treatments of psoriasis?

UV light, topical corticosteroids, cyclosporine, biologic agents

what are clinical findings of paoriasis?

nail pitting, arthritis, scales on the scalp

what disease is known for its christmas tree appearance?

pityriasis rosea gibert

what is the B-cell surface marker?

CD20

where are keloids most frequently seen?

chest, ear, shoulder

syphilis can cause baldness. true or false?

true

SLE patients present with a mask-like face. true or false?

false. butterly rash

what are the 5 types of psoriasis?

psoriasis vulgaris

guttate psoriasis

pustular psoriasis

psoriatic erythroderma

psoriatic arthritis

what is Kobner phenomenon?

when additional psoriasis occurs on non-lesional skin after injury on the site.

what are the causes of Lichen Planus?

drugs (antihypertensivee, antitubercular, cerebral excitometabolic)

hepatitis C

dental metals

how is Pityriasis rosea Gibert treated?

it heals spontaneously in 1-3 months, but topical steroids are also used.

what are the risk factors of palmoplantal pustulosis (PPP)

history of smoking, baccterial infection (tonsillitis), dental caries, dental metal allergies

what is the appearance of seborrheic keratosis?

sharply demarcated, grayish-brown to blackish-brown nodules, 1-2cm in diameter.

what is Leser-Trelat syndrome, and what is it a sign of?

seborrheic keratosis occuring rapidly in multiple itchy lesions on the whole body.

it can be a sign of internal malignancy

what is the most common site of keloids?

ear, shoulder, upper part of trunk

how are keratoacanthomas treated?

it heals spontaneously in several months.

what stain is used for epithelial tissue?

cytokeratin

what is the treatment of alopecia areata?

topical steroids and PUVA

what underlying health problems can cause alopecia?

endocrine abnormalities, infections (syphilis, leprosy, tinea capitis), collagen disease (SLE, DLE, SSc, morphea), trichotillomania.

what is the most common cause of erysipelas?

groups A (beta-hemolytic) streptococcal infections

what is the most common cause of impetigo contagiosa?

staphylococcus aureus and group a strep

what is the treatment of erysipelas?

penicillin or cephem antibiotics

what is the treatment of impetigo?

cephem antibiotics

what is the difference between furuncle and carbuncle?

furuncle only involved one hair follice. carbuncle spreads to multiple hair follicles

what are the 5 types of acne?

comedones, folliculitis, papules, pustules, superficial pus-filled cysts.

what sign is positive in staphylococcal scalded skin syndrome?

nikolsky’s sign

what are the most common types of tinea?

tinea pedis, tinea capitis, tinea corporis, tinea cruris, tinea unguium

what test is used to diagnose tinea?

KOH test

what can acanthosis nigricans be a sign of?

malignant tumor, especially stomach cancer

what types of diseases can clubbed finders indicate?

idiopathic pulmonary fibrosis, lung cancer, liver cirrhosis, cyanotic congenital heart disease, etc.

what can cause pruritis cutaneous?

underlying systemic disease (liver dysfunction, renal failure, diabetes mellitus, malignancy tumors)

describe the 6 types of eczema

atopic dermatitis (repeating eczema for more than 6 months, elevated IgE)

contact dermatitis (eczema is localized to the site of extrinsic stimulation by a foreign substance)

seborrheic dermatitis (erythematous lesions and yellowish scales where sebum is actively secreted, such as the scalp)

nummular/discoid eczema (round and large plaque on the lower leg)

stasis dermatitis (plaques on the lower thigh and varicose veins. caused by poor blood circulation due to obesity or sedentary lifestyle)

asteatotic eczema (skin dryness caused by decrease in sebum with aging or excess washing)

what are underlying associations of neutrophilic dermatosis?

myoproliferative diseases, autoimmune diseases, G-CSF usage, visceral malignancies

what is the cause of pemphigus vulgaris?

autoantibodies against Dsg3

what sign is positive in pemphigus vulgaris?

nikolsky’s sign

what is the cause of pemphigus foliaceus?

autoantibodies against Dsg1

list 5 diseases that show nikolsky’s sign

steven johnson syndrome

toxic epidermal ncrolysis

SSSS

pemphigus vulgaris

pemphigus folicaceus

what are the skin lesions of neurofibromatosis type 1?

cafe-au-leit spots

neurofibroma

what diseases are caused by antibodies against desmosomes?

pemphigus vulgaris and pemphigus folicaceus

what diseases are caused by antibodies against hemidesmosomes?

pemphigoid gestationis and bullous pemphigoid

what is dermatitis herpetiformis duhring caused by?

IgA depositions