skin disorders Flashcards
psoriasis. what is it, histo, and treatment
uncontrolled kerationcyte proliferation w very high turnover rate. erythematous plaques with silver scale. pitting of nails, psoriatic arthritis. in histology there us acanthosis (thickening of epidermis) w neutrophils. therapy includes corticosteriods, vitamin a and d, uv light, immunsupressants, tnf-a blockage
eczema
erythematous (red) and pruritic (itchy) rash with scale or crust. Histolgically -spongiosis and exocytosis. to treat-moisturize to restore epidermal barrier. cortiocosteriods, eliminate allergens
- atopic dermatitis- heritable, associated with asthma, allergic rhinitis (inflammation in nose) and urticaria (hives) esp in flexutres
- contact dermatitis- allergy via irritant
- numular- coin shape
- dyshidrotic- sides of fingernails and plantar surface
- seborrheic dermatitis- scalp, eyebrows, nose, ears. malassezzia yeast
- xerotic- common in elderly, less sebum due to less hormone. (remember that sebeccus glands increase scretion with hormones)
- linchen simplex chonicus and prurigo nodularis-chronic lichenification
- pellagra- vitamin b3 deficiency. photosensitive distribution and gi and neurological. (3 D’s- dermatitis, diarrhea and dementia )
Lichen Planus : what is it, histo, and treatment
prurtitic (iitchy), purple, polygonal, polymorphous papules
common on wrists and have lacy white oral lesions
associated with prior hep C infection sometimes
Histo- band like lymphocytic infiltrate at dermal-epidermal junction
therapy- cortiocosteriods, metronidazole
cutaneous lupus erythematosus: what is it, histo, and treatment
systemic lupus- multisystem disease with photosenstivity, butterfly rash (malar erythema). antinucleor antibodies
Discord lupus- discoid lesions. circular with red periphery, scale, papules.
Histo- vacuolization of basal layer (bubbly)
treatment-photoprotection, cortiocosteriods, immunsupressants, antimalarials.
verruca (warts) what is it, histo, and treatment
verruca vulgaris- common wart
verruca plana-flat ward-shaving
plantar warts- ususally pounded in
condyloma accuminatum- genital, std, hpv
histo- epidermal hyperplasia w viral change
treatment- cyro w liquid N2, topical salicylic acid (destroys infected tissue )
molluscum contagiosum: what is it, histo, and treatment
slightly translucent papules with keratotic center (center has kreatinocytes).
histo- molluscum bodies, cytoplasmic includions caused by mc virus
therapy- cryo, cantheridin (painless blistering agent) , chlorhexidine soap to stop spread
herpres what is it, histo, and treatment
simplex- lips type 1 and genital type 2. vesicles that cluster and recurrent at same site. can secondarily infect plaque or atopic dermatitis such as kaposi varicelliform eruption
varicella- aka chicken pox, vesicle on red base .
zoster- reactivation of varcella, dermatomal, painful even after lesions gone (post herpetic neuralgia) aka shingles
viruses can cross placenta
histo-viral nuclei change (glass cytoplasm, marginization of chromatin) epithlilal giant cells
therapy- antovirals, isolation or contact avoidance. varicella vaccine for children zoster vaccine for adults
viral exanthems : what is it, histo, and treatment
- measles- rubeola virus. pulmunary, gi, and neurological symptoms.
- german measles- rubella. resolves in three days
- scarlet fever- due to strep toxin.
—all three have diffuse fine red papular eruption with fever - fifth disease (erythema infectiosum ) parvovirus b19. bright red like cheek slap. with lace like reticular redness spreading down. dont feel sick resolves in a week’
histo- perivascular lymphocytes
therapy- vaccines, strep treated by antibiotics
pityrasis rosea
large patch (2-10cm) precedes smaller salmon scaling plaques with christmas tree pattern.
spring and dall. no definite virus proven,
lasts 2 months then resolves
histo- epidermal spongiosis
therapy-cortiosteriods for itching. maybe UV light treatment and erythromyosin
acne : what is it, histo, and treatment
driven by androgen- sebum, bacteria, plugged bores.
Clinical
a. Open comedones (blackheads – keratin and sebum, not dirt); mild acne.
b. Closed comedones (whiteheads); mild acne.
c. Erythematous papules and pustules; moderate acne.
d. Cysts, nodules, and scars; severe acne.
III. Acne vulgaris – teenagers and young adults.
IV. Rosacea – older adults.
V. Perioral Dermatitis – younger women; perioral sparing.
VI. Histology – follicular plugging with keratin and follicular
inflammation.
VII. Principles of Therapy – kill bacteria (Propionibacterium acnes)
with antimicrobials; exfoliate keratin to open pores (benzoyl
peroxide; salicylic acid; retinoids); avoid scarring with oral
retinoid, isotretinoin (teratogenic and highly regulated).
folliculitis
Inflammation of hair follicle, usually due to infection.
II. Pustules (small whiteheads), furuncles (deeper pustules, also
involve sebaceous gland), carbuncles (multiple furuncles), or
abscess (large cavity filled with neutrophils (pus).
III. Staph and Strep bacteria most commonly.
IV. Methicillin Resistant Staph Aureus (MRSA) sometimes present.V. Histology – neutrophilic collections within hair follicle or larger
cavity in the case of an abscess.
VI. Principles of Therapy – topical mupirocin; systemic antibiotics if severe; abscesses must be incised, drained, and cultured with
antibiotic sensitivity profile.
impetigo
Most common in children, but secondary impetiginization can
occur with any break in the skin (e.g. impetiginized eczema).
II. Staph and Strep bacteria.
III. Honey colored crusting, clinically.
IV. Histology – subcorneal neutrophils with bacterial colonies.
V. Principles of Therapy – topical mupirocin; systemic antibiotics ifsevere.
cellulitis
Broad erythema, edema, heat, tenderness.
II. Staph and Strep bacteria most commonly. Group A strep
secretes hyaluranidase which facilitates spread.
III. Superficial cases termed erysipelas.
IV. Severe cases can lead to ascending lymphangitis (red streak
extending proximally up an extremity).
V. Severe cases can lead to deeper necrotizing fasciitis: Strep A
bacteria; expanding erythematous plaques; progresses rapidly over the course of hours, life threatening.
VI. Histology – Edema with neutrophils extending through dermis. VII. Principles of therapy – systemic antibiotics; hospitalization for
severe cases; surgical intervention for necrotizing fasciitis
(fasciotomy for decompression)
