Ch 19 Pathoma - Skin Pathology

Question 1

Skin functions as a barrier against ___ and ___. Epidermis is comprised of ___ primarily. Dermis consists of these 4 things.

Answer 1

environmental insult; fluid loss; keratinocytes; CT, nerve endings, blood/lymphatic vessels, adnexal structures (hair shafts, sweat glands, sebaceous glands)

Question 2

Name the 3 layers of skin

Answer 2

epidermis, dermis, and subcutaneous fat (hypodermic, subcutis)

Question 3

Name the 5 layers of epidermis from surface to base and any defining characteristic.

Answer 3

Stratum: corneum (keratin/anucleate); lucidum (only seen in thick skin - palms and soles); granulosum (granules in keratinocytes); spinosum (desmosomes btwn keratinocytes); basalis (regenerative stem cell layer) (Come Lets Get Sun Burnt)

Question 4

Which inflammatory dermatoses can be defined as an pruritic, erythematous, oozing rash with vesicles and edema?

Answer 4

Atopic (eczematous) dermatitis AND contact dermatitis

Question 5

Atopic (____) dermatitis is a pruritic, erythematous, oozing rash with ___ and ___. It often involves the ___ and ___ surfaces. It is a type __ hypersensitivity reaction associated with ___ and ___.

Answer 5

eczematous; vesicles; edema; face; flexor; 1; asthma; allergic rhinitis

Question 6

Contact dermatitis is a ___, ___, and ___ rash with vesicles and edema. It arises upon exposure to ___. Name 3 types. Tx involves ___ and ___ if needed.

Answer 6

pruritic, erythematous, oozing; allergens; poison ivy/nickel jewelry (type IV hypersens); irritant chemicals (detergents); drugs (penicillin); removal of offending agent; topical glucocorticoids (steroids can also be used for eczema)

Question 7

Acne vulgaris are ___ (whiteheads/blackheads), ____ (pimples), and ____, extremely common, especially in ____.

Answer 7

comedones; pustules; nodules; adolescents

Question 8

Acne vulgaris is due to chronic inflammation of ___ and associated ___. There is a hormone associated increase in ___ production and excess ___ production block follicles, forming comedones. ___ infection produces ___ that break down ___, releasing pro inflammatory ___. Result is pustule or nodule formation

Answer 8

hair follicles; sebaceous glands; sebum (sebaceous glands have androgen receptors); keratin; Propionibacterium acnes; lipases; sebum; fatty acids

Question 9

Treatment for acne vulgaris include ___ (antimicrobial) and ___ (e.g. isotretinoin), which reduce ___ production.

Answer 9

benzoyl peroxide; vitamin A derivatives; keratin

Question 10

____ is well-circumscribed, salmon colored plaques with silvery scale, usually on ___ surfaces and the ___. ___ of nails may also be present. It is due to ____.

Answer 10

Psoriasis; extensor; scalp; pitting; excessive keratinocyte proliferation

Question 11

Psoriasis has a possible ___ etiology and is often associated with HLA-__. Lesions often arise in areas of ___ (environmental trigger). Treatment involves these 3 things.

Answer 11

autoimmune; C; trauma; corticosteroids; UV light with psoralen (P UVA); immune-modulating therapy

Question 12

Name the 4 histological markers of psoriasis.

Answer 12

1) acanthosis (epidermal hyperplasia); 2) parakeratosis (hyperkeratosis with retention of keratinocyte nuclei in the stratum corneum); 3) Munro microabcesses (collections of neutrophils in the stratum corneum); 4) thinning of the epidermis above elongated dermal papillae (results in bleeding when scale is picked off - Auspitz sign)

Question 13

___ is pruritic, planar, polygonal, purple papules, often with reticular white lines on their surface (____), which commonly involves ___, ___, and ___.

Answer 13

Lichen planus; Wickham striae; wrists, elbows, oral mucosa (oral involvement manifests as Wickham striae)

Question 14

In lichen planus, histology shows ___ of the ____ with a ___ appearance. Etiology is ___, and it is often associated with chronic ___ infection.

Answer 14

inflammation; dermal-epidermal junction; sawtooth; unknown; hep C virus

Question 15

Name the 5 P’s of lichen planus

Answer 15

pruritic, planar, polygonal, purple papules

Question 16

____ is the autoimmune destruction of desmosomes between keratinocytes. It is due to Ig__ antibody against ___ (type __ hypersensitivity reaction). It presents as __ and __ bullae.

Answer 16

Pemphigus vulgaris; IgG; desmoglein; 2; skin; oral mucosa

Question 17

In pemphigus vulgaris, there is ___ (separation) of stratum ___ keratinocytes (normally connected by ___) resulting in supra/sub-basal blisters. Basal layer cells remain attached to BM via ___, and have a ___ appearance. The bullae are thick/thin walled and do/do not rupture easily (__ sign).

Answer 17

acantholysis; spinosum; desmosomes; supra; hemidesmosomes; tombstone; thin; do; Nikolsky (the thin walled bullae rupture easily leading to shallow erosions with dry crust)

Question 18

How does the immunofluorescence that highlight IgG differ in pemphigus vulgaris vs bullous pemphigoid?

Answer 18

PV: highlights IgG surrounding keratinocytes in a fish net pattern BP: highlights IgG along basement membrane in a linear pattern

Question 19

Bullous pemphigoid is the autoimmune destruction of ___ between basal cells and underlying basement membrane. It is due to Ig__ antibody against ___ components (___) of the BM.

Answer 19

hemidesmosomes; IgG; hemidesmosomes; BP180;

Question 20

Bullous pemphigoid presents as supra/sub-epidermal blisters of the skin, usually in ___. ___ is spared, which helps tell the difference between BP and pemphigus vulgaris. Basal cell layer is attached/detached from the BM. Tense bullae do/do not rupture easily.

Answer 20

sub; elderly; oral mucosa; detached; do (clinically milder than pemphigus vulgaris)

Question 21

___ is the autoimmune deposition of IgA at the tips of dermal papillae. It presents as pruritic ___ and __ that are grouped (___). Strong association with __ disease, so it resolves with ___ diet.

Answer 21

Dermatitis herpetiformis; vesicles; bullae; herpetiform; celiac; gluten-free (IgA against gluten cross reacts with reticulin fibers that attach the BM to the dermis)

Question 22

____ is a hypersensitivity reaction characterized by targetoid rash and bullae. Targetoid appearance is due to ___ surrounded by ___.

Answer 22

Erythema multiforme; central epidermal necrosis; erythema

Question 23

Erythema multiforme is most commonly associated with ___. Name 4 other associations.

Answer 23

HSV infection; mycoplasma infxn, drugs (penicillin and sulfonamides), autoimmune disease (SLE), and malignancy

Question 24

Erythema multiforme with oral mucosa/lip involvement and fever is called ____. ____ is a severe form of it characterized by diffuse sloughing of skin, resembling a large ___. Most often due to ____.

Answer 24

Stevens-Johnson Syndrome (SJS); toxic epidermal necrolysis; burn; adverse drug reaction

Question 25

___ is a benign squamous proliferation. It is a common epithelial tumor in ____. It presents as raised, bicolored plaques on extremities or face, and often has a coin-like waxy ‘___’ appearance. It is characterized by ___ on histology

Answer 25

Seborrheic keratosis; elderly; stuck-on; keratin pseudocysts

Question 26

Leser-Trélat sign is the sudden onset of multiple ___ and suggests underlying ___.

Answer 26

seborrheic keratoses; carcinoma of the GI tract (likely a paraneoplastic syndrome)

Question 27

Acanthosis Nigricans is ___ with ___ of the skin (‘__‘-like skin), which often involves the ___ or ___. It is associated with ___ or ___

Answer 27

epidermal hyperplasia; darkening; velvet; axilla; groin; insulin resistance (type 2 DM); malignancy (gastric carcinoma)

Question 28

____ is a malignant proliferation of basal cells of the epidermis. Risk factors stem from UV_-induced DNA damage and include these 3 things. Treatment is ___. Metastasis is common/rare.

Answer 28

basal cell carcinoma; B; prolonged sun exposure; albinism; xeroderma pigmentosum (AR defect in nucleotide excision repair); surgical excision; rare

Question 29

What is the most common cutaneous malignancy?

Answer 29

basal cell carcinoma

Question 30

Basal cell carcinoma presents as an elevated ___ with a central, ulcerated crater surrounded by ___. Describe the 3 P’s. Histology shows ___ of basal cells with ___.

Answer 30

nodule; dilated vessels (telangiectatic); pink, pearl-like papule; nodules; peripheral palisading

Question 31

Classically which lip are basal cell carcinoma and squamous cell carcinoma found on respectively?

Answer 31

top, bottom (it’s a bunch of BS)

Question 32

Squamous cell carcinoma is the malignant proliferation of squamous cells characterized by formation of ___. Risk factors stem from ___ damage and include these 3 things. Name 3 additional risk factors.

Answer 32

keratin pearls; UVB-induced DNA; prolonged sun exposure; albinism; xeroderma pigmentosum; immunosuppressive therapy; arsenic exposure; chronic inflammation (e.g. scar from burn or draining sinus tract)

Question 33

Squamous cell carcinoma presents as ___, ___ mass, usually on the ___. Treatment is ___. Metastasis is common/rare.

Answer 33

ulcerated; nodular; face; excision; uncommon

Question 34

____ is a precursor lesion of SCC and presents as a hyperkeratotic, scaly plaque, often on the face, back or neck.

Answer 34

actinic keratosis

Question 35

___ is a well differentiated SCC that develops rapidly and regresses spontaneously. It presents as a __-shaped tumor filled with ___.

Answer 35

keratoacanthoma; cup; keratin debris

Question 36

Melanocytes are responsible for skin ____ and are found at the ___ layer of epidermis. They are derived from ___. They synthesize ___ in ___ using ___ as a precursor. They then pass the ___ to keratinocytes.

Answer 36

skin pigmentation; basal; neural crest; melanin; melanosomes (specialized organelles); tyrosine; melanosomes

Question 37

___ is localized loss of skin pigmentation due to autoimmune destruction of melanocytes.

Answer 37

vitiligo

Question 38

____ is a congenital lack of pigmentation. It is due to an enzyme defect (usually ___) that impairs __ production. Can involve the eyes (___ form) or both eyes and skin (___ form). There is an increased risk of these 3 cancers due to reduced protection against UVB.

Answer 38

Albinism; tyrosinase; melanin; ocular; oculocutaneous; SCC, basal cell carcinoma, melanoma

Question 39

A freckle (___) is a small, tan to brown ____, that darkens when exposed to ___. It is due to an increased number of ___ not increased ___.

Answer 39

ephelis; macule; sunlight; melanosomes; melanocytes

Question 40

___ is a mask-like hyper pigmentation of the cheeks, associated with __ and ___.

Answer 40

Melasma; pregnancy; oral contraceptives

Question 41

___ is a benign neoplasm of melanocytes. A congenital one is often associated with ___. Acquired ones arise later in life.

Answer 41

Nevus (mole)

Question 42

An acquired nevus begins as nests of melanocytes at the ____. It is the most common mole in ___. It then grows by extension into the ____ (___ nevus). The ___ component is eventually lost resulting in an ___ nevus, which is the most common mole in ___.

Answer 42

dermal-epidermal junction; children; dermis; compound; intradermal nevus; adults

Question 43

A nevus is characterized by a flat ___ or raised ___ with symmetry/asymmetry, sharp/irregular border, evenly distributed color, and small diameter (less than__ mm). ___ nevus is a precursor to melanoma

Answer 43

macule; papule; symmetry; sharp; 6; dysplastic

Question 44

Melanoma is a malignant neoplasm of ___. Risk factors are based on UVB-induced DNA damage from these 3 factors. An additional risk factor is ___ (autosomal dominant disorder characterized by formation of ___ that may progress to melanoma)

Answer 44

melanocytes; prolonged exposure to sunlight; albinism; xeroderma pigmentosum; dysplasti nevus syndrome; dysplastic nevi

Question 45

Melanoma presents as a mole-like growth with ABCDE.

Answer 45

Asymmetry; Borders are irregular; Color is not uniform; Diameter greater than 6mm; Evolution over time

Question 46

Melanoma is characterized by two growth phases. ___ growth horizontally along the ___ and ___ (increased/low risk of mets); ___ growth into the ___ (increased/low risk of mets). Depth of extension (____) is the most impt prognostic factor in predicting mets.

Answer 46

Radial; epidermis; superficial dermis; low; Vertical; deep dermis; Breslow thickness

Question 47

Name 4 variants of melanoma and anything characteristic

Answer 47

1) Superficial spreading (most common; dominant early radial growth - good prognosis); 2) lentigo maligna melanoma (lentiginous proliferation [radial growth], good prognosis); 3) Nodular (early vertical growth, poor prognosis); 4) Acral lentiginous (arises on palms or soles, often in dark skinned; not related to UV)

Question 48

Which variant of melanoma is not related to UV?

Answer 48

Acral lentiginous

Question 49

Impetigo is a superficial/deep bacterial/viral skin infection most often due to ___ or ___. It commonly presents in adults/children. It presents as erythematous ___ that progress to ___, that can rupture resulting in erosions and dry, crusted, ___-colored serum. Usually located on the ___.

Answer 49

superficial; bacterial; S aureus; S pyogenes; children; macule; pustule; honey; face

Question 50

Cellulitis is a superficial/deep infection, usually due to ___ or ___. It presents as a red, tender, swollen rash with ___. Name 3 risk factors of cellulitis.

Answer 50

deep (dermal and subq); S aureus; S pyogenes; fever; recent surgery, trauma, or insect bite

Question 51

Cellulitis can progress to ___ where you see ___ of subcutaneous tissues due to infection with ___ ‘flesh eating’ bacteria. Production of ___ leads to crepitus and it’s a surgical emergency

Answer 51

necrotizing fasciitis; necrosis; anaerobic; CO2

Question 52

Staphylococcal scalded skin syndrome causes sloughing of skin with ___ and ___. Leads to significant skin loss. It is due to ___ infection. ___ toxins result in epidermolysis of the ____.

Answer 52

erythematous rash; fever; S aureus; Exofliative A and B; stratum granulosum

Question 53

How do you histologically distinguish between toxic epidermal necrolysis (SJS) and staphylococcal scalded skin syndrome?

Answer 53

By the level of skin separation TEN: dermal-epidermal junction (deeper) SSSS: at stratum granulosum

Question 54

___ are flesh colored papules with a rough surface. Due to ___ infection of keratinocytes. Characterized by ___. __ and __ are common locations.

Answer 54

Verucca (wart); HPV; koilocytic change; hands and feet

Question 55

____ is firm, pink, umbilicate papules due to ___. Affected keratinocytes show cytoplasmic inclusions (aka ___). Most often arises in adults/children. Also seen in ___ and ___ individuals

Answer 55

Molluscum contagiosum; poxvirus; molluscum bodies; children; sexually active; immunocompromised

Question 56

What skin disorder is seen here and what is the identifying characterisitc?

Answer 56

Pemphigus vulgaris (separation of the stratum spinosum keratinocytes due to autoimmune disorder that attacks desomosomes); tombstone appearance

Question 57

What skin disorder is this? And what is it due to?

Answer 57

Bullous pemphigoid; autoimmune destruction of hemidesmosomes

(bascal cell layer detaches from basement membrane)

Question 58

What is seen here? What is the defining feature?

Answer 58

Basal cell carcinoma; basal cells with peripheral palisading