Diseases Flashcards

1
Q

allergic contact dermatitis (ACD)

A

type IV delayed hypersensitivity: T cell mediated
Sx: pruritus
rash: eczematous, scaly edematous plaques with vesicles in area of exposure
Hx: daily skin care routine, all topical products, occupation/hobbies, regular and occasional exposure (lawn care products, animal shampoos)
Tx: avoid exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

irritant contact dermatitis (ICD)

A

inflammatory reaction in skin resulting from exposure that can cause an eruption in most people (non-immunologic)
host and environmental elements
NO previous exposure necessary
single application with severely toxic substance or repeated application of mildly irritating substances (soap, detergent)
sites: thinner skin: face, neck, scrotum, dorsal hands
risk factor: atopic dermatitis
Sx: erythema, chapped skin, dry, fissuring, pruritus, pain
severe Sx: edema, exudate, tender, bull within hours
Tx: avoid irritant, topical steroids, emollients to improve barrier
prevention: protective equipment, avoidance
need patch test in occupational cases to exclude allergic contact dermatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

atopic dermatitis (AD)

A

before age 5, clears by adolescence
loss of FILAGGRIN: Th2 immunity
mutlifactorial: genetics, skin barrier dysfunction, impaired immune response, environment
type I hypersensitivity triad: allergic rhinitis, bronchial asthma, AD
chronic, pruritic, inflammatory skin disease
Sx: pruritus, xerosis
ITCH that RASHES: erythematous papules that coalesce to plaques with weeping, crusting, or scaling
Tx: avoid trigger, anti-inflammatory therapy, skin care to compensate for genetically determined impaired barrier, emollients (petrolatum), topical steroids, tacrolimus, pimecrolimus, oral steroids, phototherapy in refractive cases, oral antibiotics if infected with staph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

dyshidrotic dermatits

A

firm vesicles of the palms, soles, lateral and medial fingers and toes
Sx: pruritus, burning, prickling sensation
associations: atopic dermatitis, contact dermatitis
NO disturbance of sweat gland function
may be related to stress, atopy, allergens (topical and ingested)
Tx: steroids (topical and systemic), topical calcineurin inhibitors, consider underlying allergen/irritant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Lichen simplex chronicus

A

chronic, intensely pruritic skin condition triggered by repeated rubbing and scratching
Sx: solitary, well-defined, pink to tan, thick and lichenified plaque
locations: lateral neck, scrotum/vulva, and dorsal foot
Tx: topical steroids and break habit of scratching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

acute dermatitis

A

appears vesicular or bullous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

chronic dermatitis

A

red, scaly and lichenified with fissures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

pruritus

A

itching

common in all types of dermatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

causes of contact dermatitis

A

most common: Rhus dermatitis: poinson ivy, oak, sumac (all contain urushiol)
other: nickel, rubber, fragrance, preservatives, formaldehyde, topical antibiotics, benzocaine, Vitamin E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two phases of allergic contact dermatitis?

A
  1. sensitization (induction): 10-14 days

2. elicitation (challenge): dermatitis within 12-48 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Rhus allerg

A

allergic contact dermatitis: poison ivy, sumac, oak
initial episode: rash 7-10 days after exposure
duration: up to 6 weeks
other episodes: within 2 days
duration: 10-21 days
Tx: topical steroids, antihistamine, oatmeal soak/ calamine lotion
severe: oral steroids for 2-3 weeks
prevention: avoid plants, wash objects exposed, apply barriers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

eyelid allergic contact dermatitis

A

causes: often from transfer from hands: nail polish, cosmetics, nickel
Sx: intensely pruritic
scaling red plaques greater on upper lids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

patch testing

A

determines which allergens a patient with allergic contact dermatitis reacts against
use ONLY when allergen is unclear
apply to back, remove in 2 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

latex allergy (2 types)

A

delayed hypersensitivity: allergic contact dermatitis on dorsal surface of hands
immediate hypersensitivity: immediate burning, stinging, itching with or without localized urticaria, may include disseminated urticaria, allergic rhinitis, anaphylaxis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

location of atopic dermatitis lesions by age

A
  1. infants and toddlers: eczematous plaques on cheeks, foreheads, scalp, extensor surfaces
  2. older children, adolescents: lichenified eczematous plaques in flexural areas of neck, elbows, wrists, ankles
  3. adults: lichenification in flexural regions and involvement of hands, wrists, ankles, feet, face (forehead and around eyes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

eczema herpeticum

A

severe herpes simplex virus infection in atopic dermatitis patient
severe cases require hospitalization
Tx: IV acyclovir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

nummular dermatitis/ discoid eczema

A

older
coin shaped, well demarcated plaques with scales and tiny vesicles
location: legs, dorsal hands, extensor surfaces
Sx: intensely pruritic, worse in winter (DRY SKIN)
Tx: topical steroids, topical tacrolimus or pimecrolimus, emollients, phototherapy
may be linked to impaired skin barrier function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

urticaria

A

rapid development of hives: evanescent, itchy swellings of skin
wheals last few hours before resolving, may have angioedema up to 72 hrs
*consider urticarial vasculitis if wheals last longer than > 24 hrs
HISTAMINE release and other cytokines: edema
can be allergic or non-allergic, with or with our identifiable cause
Prevent: antihistamines, leukotriene antagonists, H2 blockers
usually avoid steroids: risk of rebound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

causes of urticaria

A

acute ( 6 weeks): unknown, chronic infection, rheumatologic disorder, Ab to IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

angioedema

A

swelling of deep dermis and subcutaneous tissue
more frequent with food induced urticaria
typically face: lips, periorbital, hands, feet
also: tongue larynx, respiratory, GI: can cause anaphylaxis (wheezing, difficulty breathing, abdominal pain, dizzy, low BP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

hereditary angioedema

A

C1 inhibitor deficiency

recurrent episodes of edema, abdominal pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

angioedema without urticaria

A

often drug therapy related

angiotensin-converting enzyme inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

physical urticarias

A

not immunologic; physical cause

dermatographism, cold/heat ,delayed pressure , solar, aquagenic, cholinergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

cutaneous drug reactions

A

risk: increased age, female, concomitant viral infection (HIV, EBV)
common causes: antibiotics, anticonvulsants, NSAIDS
rash: morbilliform (maculopapular) or urticarial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

morbilliform drug reaction

A

type-IV hypersensitivity: cell-mediatedmorbilliform
MOST common
5-7 days after starting drug (even few days after drugs is discontinued)
penicillins, cephalosporins, sulfonamides
anticonvulsants
Tx: resolve spontaneously in one to two weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

urticarial drug reactions

A
immediate hypersensitivity: IgE mediated
requires prior exposure
penicillins, cephalosporins
aspirin
latex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

drug rash with eosinophilia and systemic systems (DRESS)

A

drug hypersensitivity syndrome
severe morbillifrom drug reaction with eosinophilia and systemic illness
onset: 2-6 weeks after exposure, facial edema, fever, lymphadenopathy, joint pain, liver
persists weeks to months after drug is stopped
cause: anticonvulsants, antibiotics (sulfonamides, minocycline, erythromycin)
Tx: long term with corticosteroids
mortality: 10% from fulminant hepatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

fixed drug eruption

A
well circumscribed, red brown plaque, may blister
heals with hyper pigmentation
same location with repeated exposure
location: genitals, lips, extremities
causes: sulfonamides, NSAIDS, laxatives
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

stevens-johnson syndrome/toxic epidermal necrolysis

A

life-threatening blistering skin and MUCOUS membranes
onset: 1-2 mo. starting drug
Sx: flu like, mucosal irritation, conjunctivitis, dysuria
rash: starts morbillifrom or dusky target lesions, painful or burning; skin peels full thickness
multisystem involvement
Tx: remove drug, supportive care in burn unit, IV immunoglobulin
high mortality
steroids increase mortality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

drugs associated with stevens-johnson syndrome

A

antibiotics: sulfonamides, penicillins, cephalosporin
anticonvulsants: phenobarbital, carbamazepine, lamotrigine
allopurinol, NSAIDS (oxican derivatives), nevirapine, abacavir, acetaminophen in children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the difference between stevens-johnson syndrome and toxic epidermal necrolysis?

A

less than 10% body area: SJS
10-15%: overlap
greater than 15%: TEN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

bullous pemphigoid

A

female, old
Ab to HEMIDESMOSOMES
target antigens: BP 180/230
Sx: very itchy urticarial rash, tense blisters (usually symmetric distribution) with/out surrounding erythema, mucous membrane involvement in a few
DIF: solid line with IgG and C3 at dermal-epidermal junction
Dx: skin biopsy for DIF
may or may not find Ab in blood
Tx: systemic steroids, immunosuppressants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

pemphigus vulgaris

A

50-60 yrs, men
Mediterranean, Ashkenazi Jew
Ab to DESMOSOMES
target antigen: desmoglein 1/3
Sx: erosion in mouth, painful erosions, if have blisters they break easy
location: head, chest, back, intertriginous areas (armpit, groin), extensive membrane involvement (mucosa, larynx, esophagus, conjunctiva)
Dx: skin biopsy: DIF; serum Ab
Tx: steroids, immunosuppressants, Rituximab
high fatality without Tx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

dermatitis herpetiformis

A
men, 30-40
autoimmune
CELIAC disease: enteric GLUTEN sensitivity 
EPIDERMAL TRANSGLUTAMINASE
IgA Ab to e-TG
Sx: GI, intensely itchy (may see blisters)
location: elbow, butt, knee, scalp, neck
Tx: gluten free diet, dapsone for itch
complication: lymphoma
35
Q

hemidesmosome

A

attach epidermis to BM

BULLOUS PEMPHIGOID

36
Q

mucous membrane pemphigoid

A

Ab to hemidesmosomes
scarring eye involvement, can lead to blindness; oral lesions
with/out skin lesions

37
Q

gestational pemphigoid (herpes gestationis)

A

Ab to hemidesmosomes
bullous pemphigoid in pregnant women (2nd trimester), can reoccur with successive pregnancies or oral contraceptives
associated with preterm labor or low weight for gestational age
regresses post partum

38
Q

pemphigus foliaceus

A

superficial pemphigus
Brazil
Ab to desmoglein 1
Sx: scale crust resembles corn flakes

39
Q

paraneoplastic pemphigus

A

pemphigus associated with malignancy

sever and recalcitrant mucosal involvement

40
Q

tissue transglutaminase (t-TG)

A

CELIAC

cross reacts with epidermal transglutaminase (e-TG)

41
Q

transglutaminases

A

cytoplasmic Ca dependent enzymes that catalyze crosslinks between glutamine and lysine
important in forming insoluble protein polymers: blood clots hair, skin

42
Q

BP 180 or BP 230

A

BULLOUS PEMPHIGOID

43
Q

desmosomes

A

attach keratinocytes to one another

PEMPHIGUS VULGARIS

44
Q

desmoglein 1 and 3

A

PEMPHIGUS VULGARIS

45
Q

epidermal transglutaminase (e-TG)

A

DERMATITIS HERPETIFORMIS

46
Q

purpura

A

non-blanchable, pink to purple macules/patches or papule causes by extravasated RBCs in skin or mucus membranes
blood under skin (press and don’t blanche)
causes: coagulation/clotting abnormalities, leaky or abnormal vessels, trauma

47
Q

macular/non-palpable purpura

A

generally non-inflammatory

48
Q

palpable purpura

A

sign of vasculitis

49
Q

petechiae

A

non-palapable purpura

small,

50
Q

ecchymosis

A

non-palpable purpura
larger area of purpura > 5 mm
may be painful or tender
abnormalities in COAGULATION: hyper or hypo

51
Q

multifactorial causes of purpura

A
  1. thrombocytopenia and infection/trauma/inflammation
  2. abnormal platelet and infection/trauma/inflammation
  3. infection
  4. anticoagulant and trauma (DIC, renal/hepatic dysfunction,Vit. K deficiency, anticoagulation drugs)
  5. poor dermal support and trauma (actinic damage, amyloid, steroid atrophy, scurvy, fragility syndromes)
52
Q

palpable purpura

A

associated with inflammation in blood vessels

hallmark of leukocytoclastic vasculitis

53
Q

vasculitis

A

affects skin primarily and visibly

can effect: kidneys, lungs, CNS, GI

54
Q

small vessel vasculitis

A

palpable purpura, blisters, less commonly hives
Henoch Schonlein purpura (IgA)
infection, drug reaction, autoimmune, malignancy related. idiopathic, hypersensitivity

55
Q

small/medium vessel vasculitis

A

ANCA associated: Churg-strauss, microscopic polyangiitis, Wegner’s granulomatosis
Cryoglobulinemic vasculitis

56
Q

medium vessel vasculitis

A

nodules, purpura, livedo reticularis/racemosa

polyarteritis nodosa

57
Q

large vessel vasculitis

A

less likely to affect skin

Giant cell arteritis, Takayasu arteritis, Behcet’s

58
Q

retiform purpura

A

NETLIKE pattern of ecchymosis
results from vascular ischemia due to underlying thrombotic disorder (acquired or congenital)
ill patient with fever with retiform purpura: INFECTION (meningococcemia is most worrisome)

59
Q

purpura fulminans

A

widespread retiform purpura

60
Q

psoriasis

A

20s, 50s
T cell mediated
familial
mucosal changes, geographic tongue
NAIL disease: oil spots, nail pitting, distal onycholysis, subungual debris
risk of: arthritis, obesity, DM, hyperlipidemia, HTN, CV disease
flares associated with: group A strep, drugs, stress
Tx: phototherapy, TNFa inhibitors, IL12/23 blocker, IL-17 blocker
topical: steorids, retinoids, vit. D, topical keratolytics, tar
NOT systemic steroids: risk of flare with discontinuing

61
Q

seborrheic dermatitis

A

inflammatory rxn to MALASSEZIA (Pityrosporum ovale) yeast that thrives on old producing skin: sebum production
erythematous or hypopigmented greasy scaling patches on scalp, hairline, eyebrows, eyelids, central face, nasolabial folds, external auditory canal or central chest
worse in HIV
Tx: low potency topical steroids, topical ketoconazole, topical pimecrolimus, antidandruff shampoo (ketoconazole, selenium sulfide, zinc pyrithione)

62
Q

pityriasis rosea

A

young 10-35 yrs
HHV6/7 possible
salmon, purple, brown or gray: herald patch first, second CHRISTMAS TREE trunk and extremities (follow tension lines)
Sx: none or flu-like
Tx: resolves on own in 5-8 wks
if it itches: OTC anti-itch lotion, topical steroid, antihistamine, oral erythromycin

63
Q

Lichen planus

A

middle-age
autoimmune rxn to antigens on lesional keratinocytes
idiopathic inflammatory disease of skin, hair, nails, mucous membranes
pruritic, purple, polygonal, flat topped papule with reticulated network of white lines (Wickham’s striae)
lesions koebnerize: FLEXOR wrists, forearms, dorsal hands, lower legs, pre sacral area, neck glans penis
associations: HEP C
Tx: topical/ intralesional corticosteroids

64
Q

plaque type psoriasis

A

MOST COMMON
well demarcated, erythematous plaques with adherent silver to while scale
scalp, extensor surfaces of extremities, periumbilical and sacral trunk

65
Q

guttate type psoriasis

A

second most common
young adults
multiple small drop shaped erythematous scaly plaques diffusely on body: mostly trunk
often preceded by streptococcal infections (PHARYNGITIS)
Tx: antibiotics if caused by strep

66
Q

pustular type psoriasis

A

superficial pustules localized on palm and soles or general

67
Q

inverse psoriasis

A

intertriginous areas

68
Q

erythrodermic psoriasis

A

diffuse erythroderma with fine scaling

69
Q

Koebner phenomenon

A

psoriasis at sites of trauma

70
Q

cradle cap

A

infantile seborrheic dermatitis

pink to yellow macule and patches with white greasy scales on scalp, face, diaper area

71
Q

inverse pityriasis rosea

A

confine to groin and axilla

72
Q

lichen planopilaris

A

follicular variant of lichen plans that causes scarring alopecia

73
Q

lichen planus clinical variants

A
  1. annular
  2. bullous
  3. hypertrophic
  4. inverse
  5. linear
  6. ulcerative
  7. vulvovaginal-gingival
  8. drug induced
  9. lichen planopilaris
    difficult to treat mucosal; hypertrophic needs high potency under occlusion or intralesional steroids
74
Q

drug induced lichen planus

A

photodistribution or indistinguishable from idiopathic

drugs: ACE inhibitors, thiazides, antimalarials, quinidine, gold

75
Q

sarcoptes scabiei (scabies)

A

direct contact or fomites
infestation to Sx: 3-4 wks (re-infestation only 1-2 days)
location: axillae, breasts, umbilicus, penis, scrotum, finger webs, wrists
head and scalp in infants, elderly, immunocompromised
Dx: skin scraping (mineral oil prep)
Sx: itching at NIGHT
Tx: two topical tx one week apart with Rx (permethrin cream, precipitated sulfur, oral ivermectin) neck down and leave overnight (include face and scalp for infants and elderly)
itch/lesions can persist for 2-4 wks after Tx
environment: wash clothing and linens, high heat dry, seal others in bad 3 days

76
Q

pediculosis (lice)

A

school age (any socioeconomic), less in AA
live eggs remain close to scalp (1cm): can estimate duration
spread: close contact, fomites
viable egg: tan/brown
hatched: white
Sx: itching, posterior cervical LAD, dermatitis at posterior neck
Dx: nits/lice (more likely to see nits, lice scurry away from light)
Tx: topical permethrin, re-treat in 7-9 days to kill newly hatched, nit comb
resistant: malathion
other: examine/treat household, wash bedding, clothing and dry on hot, brushes hot water for 10 min, plastic bad 3 days for non washables

77
Q

lyme disease

A

Borrelia spirochete, IXODES tick
NE US: MINNESOTA, WISCONSIN
ERYTHEMA MIGRANS
Tx: early doxycyline, amoxicillin, cefuroximine

78
Q

bed bugs

A

CIMEX LECTULARIUS feed at NIGHT
all populations
spread: travel
linear array bites: breakfast, lunch and dinner
edematous papules scattered over the body, some excoriated (can have no rxn)
resolve 1-2 weeks
Tx: for symptoms antihistamines, topical steroids
launder bed linens, vacuum furniture, exterminator

79
Q

risk factors for scabies

A
  1. women, children
  2. immunocompromised
  3. congregated facilities
80
Q

crusted scabies

A

hyperkeratotic
thick, scaly, white-gray plaques with minimal itching
scalp, face, back, buttocks, feet
fissures provide entry for bacteria; sepsis, death
immune suppressed or neurological impaired
Tx: oral ivermectin, topical permethrin
ISOLATE

81
Q

pediculus humanus var capitis

A

head lice

retroauricular and occipital scalp easiest to see nits

82
Q

pediculus humanus var. corpis

A

body lice
back, neck, shoulder, waist
nits and lice on clothing

83
Q

phthirus pubis

A

pubic or crab lice

lower abdomen, pubic area, thighs