Path-Brs-Skin

Front 1

eczematous dermatitis
-et?
-morph?

Back 1

-pruritic inflamm dz

ETIOLOGY:

1. Infxn

2. Chemicals= contact dermatitis
-Type 4 hypersens: Th lymphs & Langerhans cells (macs)

3. Atophy (allergy)
-ppl w/Type 1 hypersens (bronchial asthma, hay fever) are at higher risk even tho it's Type 4 hypersens


MORPHOLOGY:
1. Acute
*spongiosis w/vesicles

2. Chronic
*acanthosis
*hyperkeratosis


3. Subacute
*b/w acute and chronic:
-less spongiosis & vesiculation as acute
-less acanthosis & hyperkeratosis than chronic

Front 2

lichen simplex chronicus

Back 2

AKA Neurodermatitis
-inflammatory

-psychogenic origin ("Neuro")
-clinically indistinguishable from eczematous dermatitits, but results solely from excessive scratching w/no bio cause of itchiness

Front 3

psoriasis (jeff)

Back 3

-chronic inflammatory dz

-non-pruritic (not itchy)
-well-demarcated patches & plaques
-silvery scales
-lesions on extensor surfaces of elbows and knees, and scalp and sacral area
*characteristic parakeratosis

-maybe autoimmune etiology, assoc w/severe Rh arthritis (another autoimm dz): "psoriatic arthritis"

Front 4

macule

Back 4

flat, non-palpable lesion of a diff color than surrounding skin

<1 cm diameter

Front 5

patch

Back 5

~macule but >1cm diameter

(macule=flat, non-palpable lesion of diff color than surrounding skin)

Front 6

papule

Back 6

elevated, palpable lesion

<1 cm diameter

Front 7

patch

Back 7

~papule but >1cm diameter

(papule=elevated palpable lesion)

Front 8

vesicle

Back 8

fluid-containing blister

<0.5 cm diameter (vs. bulla)

Front 9

bulla

Back 9

fluid-containing blister

>=0.5 cm diameter (vs vesicle)

Front 10

pustule

Back 10

blister containing pus

Front 11

crust

Back 11

dried exudate from vesicle, bulla, or pustule

(vesicle & bulla are blisters that contain fluid,
pustules are blisters that contain pus)

Front 12

hyperkeratosis

Back 12

incr thickness of stratum corneum

Front 13

parakeratosis

Back 13

hyperkeratosis + retention of nuclei of keratinocytes

(hyperkeratosis=incr thickness of stratum corneum)

Front 14

acanthosis

Back 14

thickening of epidermis

Front 15

spongiosis

Back 15

epidermal intracellular edema + widening of intercellular spaces

Front 16

acantholysis

Back 16

separation of epidermal cells from each other
==>cells appear to float in ECF

Front 17

lichenificaton

Back 17

accentuation of skin markings by scratching

Front 18

varicella

Back 18

-fever + generalized vesicular eruption (vesicle=fluid filled bister, <0.5cm diam)
-latent in DRG; can appear in dermatome (shingles AKA herpes zoster) later in life

Front 19

pemphigus vulgaris

Back 19

-life-threatening (mneum: "it's so VULGAR that it's life-threatening)
-autoimmune destruction of desmosomes (epidermal INTERcellular cement substance), spares basal layer
==>acantholysis (separation of epidermal cells; cells just float in ECF)

-first lesions occur in oral mucosa, then spreads to skin
==>lesions rupture
==>large denuded surfaces subject to secondary infxn

-immunofluorescence throughout epidermis

Front 20

bullous pemphigoid

Back 20

("pemphigoid"==>similar to PEMPHIGUS vulgaris)

-like pemphigus vulgaris, but much less severe/dangerous
-autoimmune destruction of hemidesmosomes=epidermal BM (vs. desmosomes--pemphigus vulgaris)
-spares oral mucosa (vs. pemphigus vulgaris)

-linear band of immunoflorescence across BM (vs. pemphigus vulgaris: immunoflourescence throughout entire epideermis)

Front 21

dermatitis herpetiformis

Back 21

-pruritic blistering D/O
-lesions on extensor surfaces of elbows/knees, scalp, sacral, upper back
*assoc w/celiac sprue (anti-gluten/gliadin Ig)
-IgA deposits at tips of dermal papillae

Front 22

erythema multiforme

Back 22

-"target lesion" (looks like bulls eye)
-"multiforme"==>MULTIPLE types of lesions (macules, papules, vesicles)
-assoc w/:
~hypersensitivity to coexistent infectious agents/drugs
~CT d/o
~malignancy