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Flashcards in Misc skin conditions Deck (62)
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1
Q

How common is psoriasis? Do genetics and location play a factor?

A
  • affects 1-9% of the pop: more prevalent the further away from the equator
  • equal incidences in M:F
  • hereditary: up to 40% of pts have first degree relative with psoriasis or psoriatic arthritis
2
Q

PP of psoriasis?

A
  • normal cell turnover in epidermis takes about 27 days
  • cell turnover in psoriasis is reduced to 4 days
  • massive increase in number of cells produced and normal cell keratinization doesn’t take place
  • subdermal blood vessel dilation also seen (contributes to eryrthema)
  • kertatinocytes have shortened cell cycle time of 1.5 days compared to 13 days
  • autoimmune component: T lympchocytes and dendritic cells, mult T cells are present in psoriatic lesions, therapies that suppress T cells are very effective
3
Q

Psoriasis RFs?

A
  • family hx
  • strep infection can trigger guttate psoriasis
  • meds: BB, lithium, anti-malaria
  • smoking, obesity, and alcohol are assoc
  • Vit D deficiency? (greater distance away from equator)
4
Q

Presentation of psoriasis?

A
- bimodal age distribution:
early 30-39 yrs
late 50-69 yrs
- can also occur in kids but less common than in adults
- may be gradual onset or sudden
- pruritis is common
- hx of improvement with sun exposure
5
Q

Assoc conditions of psoriasis?

A
  • psoriatic arthritis
  • CV disease, malignancy, DM, metabolic syndrome, HTN, IBD, serious infections
  • ocular involvement: swollen lids, conjunctivitis, xerosis, uveitis (think autoimmine)
6
Q

Types of psoriasis?

A
  • plaque
  • inverse
  • guttate
  • erythrodermic
  • pustular
  • nails
7
Q

Characteristics of plaque psoriasis?

A
  • MC
  • 75-80% of cases
  • slow-forming
  • stable
  • usually well defined and symmetrical
  • typically appears on knees, scalp, elbows, lower back, and can affect nails
    diff from eczema - b/c psoriasis on extensor sides, more scales
8
Q

Plaque psoriasis presentation?

A
  • salmon pink papules and plaques, sharply marginated with marked silvery-white scaling
  • scales are losse and easily removed by scratching
  • removal of scales results in small blood droplets (Auspitz sign)
  • plaque at sites of former skin injury (koebner’s phenomenon)
  • plaques turn to powder if manipulated, have odor
9
Q

Etiologies of koebner’s phenomenon?

A
  • psoriasis plaques that form at site of skin injury
  • up to 50% of pts may experience this
  • occurs 1-2 wks after injury
    may occur from:
  • bug bites
  • bruises and scrapes
  • poison ivy or poison oak
  • burns, chemical and sunburn
  • constant pressure and rubbing, vaccinations, skin blemishes, herpes, chickenpox, acupuncture
10
Q

Distribution of psoriatic lesions?

A
  • often symmetrical
  • favors elbows, knees, scalp and intertriginous areas
  • uncommon on the face
  • single lesion or lesions localized to one area or can be over the entire body
11
Q

What is inverse psoriasis?

A
  • sharply demarcated plaques
  • found in axilla, groin, naval, submammary region, palms, scalp, and soles
  • no scales like plaque psoriasis
  • more common in overwt pts
  • diff to distinguish from candidiasis w/o bx (look for satellite lesions, KOH)
12
Q

What is Guttate psoriasis?

A
  • AKA: eruptive psoriasis: has an abrupt onset
  • characteristically occurs in young adults and kids: strong assoc b/t recent strep infection (usually pharyngitis) in preceeding 2-3 wks
  • mult small teardrop shaped erythematous papules on arms, trunk
  • scattered diffusely on proximal extremtities
  • usually self limiting in a few weeks to months
13
Q

What is erythrodremic psoriasis?

A
  • most generalized: often affects most or all of body’s surface
  • erythema and scaling from head to toe: skin looks burnt, sheds in sheets
  • inflammatory
  • least common
  • severe itching and pain as skin reddens and sheds
  • HIGH RISK of SYSTEMIC INFECTION and electrolyte imbalances
  • need inpt management
14
Q

What is pustular psoriasis?

A
  • can be generalized
  • severe form with life threatening complications
  • acute onset of widespread erythema, scaling and sheets of superficial pustules with erosions characterizes the most severe variant
  • can be assoc with malaise, fever, diarrhea, leukocytosis, and hypocalcemia
  • a milder form may just affect the fingers
15
Q

What are the most common precipitating factors for erythrodermic and pustular psoriasis?

A
  • acute withdrawal of systemic corticosteroids

- can occur in those with other forms of psoriasis but also occurs in pts w/o psoriasis

16
Q

What is nail psoriasis closely assoc to?

A
  • psoriatic arthritis
  • may appear b/f onset of cutaneous psoriasis
  • nails have pitted appearance, may lift up (onycholysis - oil drop sign)
17
Q

Have to distinguish nail psoriasis with subungual hyperkeratosis from what?

A
  • from fungal infection

- do KOH

18
Q

General tx guidelines for plaque psoriasis?

A

tx:
exacerbating factors
use both systemic and topical therapy

19
Q

What are some drugs that may exacerbate psoriasis?

Soln to this?

A
  • BBs, NSAIDs, lithium, ACEI, digoxin
  • consider switching med if possible
  • combo therapy for tx is the trend to minimize SEs
20
Q

What are diff types of topical therapies used for plaque psoriasis?

A
  • emollients
  • steroids
  • Vit D analogues
  • topical retinoids
  • Calcineurin inhibitors
  • coal tar preps
  • phototherapy: UVA, UVB
21
Q

Use of emollients for tx of psoriasis?

A
  • useful in all cases as adjunct
  • hydrate stratum corneum
  • decrease water evalp.
  • soften the scales of the plaques
  • some available agents:
    Eucerin
    Lubriderm
    moisturel
  • lubricating creams are applied 2x daily after bathing, while skin is still damp.
22
Q

Use of topical steroids as tx for psoriasis? How long should they stay on these? Diff preps?

A
  • 1st line agent!!
  • can be cont. as long as pt has thick active lesions (not worried about long term use causing damage to skin b/c of high turnover rate)
  • back off on frequency and strength once better under control
  • for thick plaques on extensor surfaces - can use potent preps (betamethasone 0.05% or clobetasol propionate 0.05%)
  • often used in conjunction with topical vit D analog, topcial retinoid or UVB therapy
23
Q

Use of vit D analogues? Ex?

A

Calcipotriol (Dovonex):

  • causes immune modulation
  • used in mild to mod plaque psoriasis
  • SEs include hypercalcemia and hypercalciuria when topical doses exceed 100g/wk
  • too irritating for face or groin
  • may be used as monotherapy with steroids for breakthrough or just a few days a week
24
Q

use of Vit A derivatives (retinoids) in psoriasis tx?

A

Tazarotene (Tazorac):

  • modulates differentiation and proliferation of epithelial tissue and exerts some degree of anti-inflammatory and immunological activity
  • may cause skin irritation
  • effective with little systemic absorption
25
Q

Use of Calcineurin inhibitors? What areas are these good to use on?

A

Tacrolimus (Protopic)
Pimecrolimus (Elidel)
- inhibits T-lymphocyte activation by binding to intracellular protein, FKBP-12 and complexes with calcineurin dependent proteins to inhibit calcineurin phosphatase activity
- good to use on intertriginous areas and the face where steroid use should be limited
- not generally used as mono therapy as steroids are most effective

26
Q

Use of coal tar preps for psoriasis tx? Downside?

A
  • when used alone only as effective as mild-mildpotency topical steroids
  • primarily used as add on therapy
  • also tends to enhance the effects of UVB therapy
  • tar shampoos benefical for scalp lesions in combo with topical steroid solns
  • OTC
  • use is limited by staining of clothes and odor
27
Q

Use of phototherapy in Psoriasis?

A
  • has antiproliferative effects by slowing keratinization and anti-inflammatory effects by inducing apoptosis of pathogenic T cells
  • UV radiation will accelerate photodamage and risk of skin cancer
  • UVB
  • PUVA: UVA radiation admin. with psoralen bath or oral dose (photosensitizing drug)
28
Q

Systemic therapy for psoriasis?

A
  • for severe cases resistant to topical tx
  • methotrexate
  • acetretin (systemic retinoid): psoriatane
  • systemic calcineurin inhibitor: cyclosporine
  • biologic agents: infliximab (remicade)
  • other immune suppressants: Hydroxyurea, azathiprine
29
Q

What is urticaria?

A
  • hives
  • immune mediated skin eruption of well-circumscribed wheals on an erythematous base
  • IgE mediated
30
Q

What is angioedema?

A
  • hypersensitivity rxn involving the deep layers of skin (fluid influx)
  • swelling of the lips, eyelids, palms, soles, genitalia
  • 50% urticaria+angioedema
  • 40% urticaria alone
  • 10% angioedema alone
31
Q

PP of urticaria and angioedema?

A
  • allergen - leads to IgE ab attached to mast cell - sudden releas of immunologic mediatiors - lead to inflammation
  • idiopathic chronic urticaria thought to be caused by autoimmune process
  • principle mediator released by mast cell is histamine
32
Q

Presentation of urticaria?

A
  • characteristic edematous, erythematous, well-circumscribed blanching wheals
  • these can range from a few mm to several cm
  • serpinginous borders
  • lesions may persist for 12-24 hrs but most resolve sooner than this
33
Q

Presentation of food and drug induced urticaria?

A
  • attacks tend to be brief
  • usually don’t cause chronic urticaria
  • may be accompanied by angioedema
34
Q

What is dermatiographism?

A
  • gentle stroking of the skin produces immediate wheal and flare response
35
Q

What is pressure urticaria?

A
  • pressure to skin at right angle results in red swelling after latent period of up to 4 hrs
36
Q

What is cold urticaria?

A
  • eruptions w/in minutes following application of cold
37
Q

What is cholinergic urticaria?

A
  • punctuate hive triggered by exercise or hot shower
38
Q

What is aquagenic urticaria?

A
  • hives after contact with water
39
Q

What is solar urticaria?

A
  • hives develop following exposure to UV light
40
Q

Possible urticaria assocns?

A
  • autoimmune disease: may describe idiopathic cases of chronic urticaria
  • infectious disease: sxs tend to occur in prodromal phase of hepatitis B, some pts with chronic idiopathic urticaria had resolution of sxs following tx for H. pylori
41
Q

Key to eval of urticaria and angioedema?

A
  • thorough hx
  • goal is to ID a specific cause or precipitant
  • Have pt keep diary
42
Q

Management of urticaria and angioedema?

A
  • avoidance of etiologic agent if ID
  • avoidance of substances that may aggravate:
    ASA, NSAIDs, ETOH, ACEI
43
Q

Use of antihistamines and steroids in sx tx of urticaria and angioedema?

A

antihistamines:

  • sedating and/or nonsedating H1-blockers (benadryl, allegra)
  • refractory cases: H2 blockers (ranitidine), 15% of receptors in cutaneous vasculature are H2 receptors
  • doxepin (sinequan) is TCA with some H1 and H2 blocking activity

steroids - generally reserved for a trial of max dose of antihistamines

44
Q

When is subq epi used?

A
  • for severe attacks (anaphylaxis like rxns)
45
Q

% of pts that are free of urticaric lesions in a yr?

A
  • half of pts with urticaria alone and 25% with urticaria assoc with angioedema are free of lesions w/in 1 yr
46
Q

What should you look into with a pt that has urticaria and has h&p suggestive of other diseases?

A
  • H. Pylori and thyroid disease
47
Q

What is Vitiligo? Where do lesions occur?

A
  • onset usually early in life (20-30yo)
  • lesions occur primarily on face, upper trunk, finger tips, hands, arm pits, genitalia, bony prominences and perioral region
  • hair may be white in involved areas
48
Q

PP of vitiligo?

A
  • autoimmine mechanism with formation of abs to melanocytes
  • often occurs in contrext of other autoimmune conditions such as pernicious anemia and Hashiomoto’s thyroiditis
  • not life threatening but can emotionally affect the pt
49
Q

Tx of vitiligo?

A
- repigmentation can be achieved to variable degrees with:
topical steroids 
tacrolimus
psoralens
UVA, UVB
surgical skin grafting
- long process, reqrs pt commitment
- may need pysch support
50
Q

What is pemphigus? Mortality rate?

A
  • rare, chronic, potentially fatal disease of the mucous membranes and skin
  • intraepidermal blistering secondary to an autoimmune process
  • mortality rate as high as 5%
51
Q

Characteristics of pemphigus?

A
  • blistering rash
  • flaccid bullae that often begin in oropharynx and then spread to involve scalp, face, chest, axillae, and groin
  • bullae are tender and painful
  • have nikolsky sign (top skin layer pulls away from bottom layer when rubbed)
  • skin bx reqd for dx
52
Q

Tx of pemphigus?

A
  • recognize and refer
  • may reqr hospital admission for severe disease
  • tx with systemic corticosteroids and immunosuppressives
53
Q

What is bullous pemphigoid? May be triggered by? How common is it? MC presentation?

A
  • chronic, subepidermal blistering autoimmune disease
  • may possibly be triggered by a drug rxn or infection
  • almost exclusively in elderly pop (older than 60)
  • 2x as common as pemphigus
  • MC presentation is widespread blistering eruption
  • increased mortality
54
Q

Characteristics of bullous pemphigoid? Tx?

A
  • assoc urticarial plaques
  • blisters are tense and fluid filled
  • skin bx reqd

tx:

  • recognize and refer
  • 1st line topical high dose (preferred) or oral steroids
  • may reqr immunosuppressants
55
Q

Epidermoid cysts are aka? Characteristics?

A

AKA: sebaceous cyst, infundibular cyst, epidermal cyst

  • MC cutaneous cyst
  • derived from epidermis or epithelium
  • becomes filled with keratin and lipid rich debris
  • rupture is common, may result in painful inflammatory mass
  • may become secondarily infected if ruptures b/c communicates with skin
56
Q

What is a dermatofibroma?

A
  • very common, button like dermal nodule
  • lesion may be tender
  • benign but can be confused with dangerous lesions
57
Q

What are lipomas? What is familial lipoma syndrome?

A
  • benign subq tumors
  • soft, rounded, and movable against the overlying skin
  • composed of fat cells that have the same morphology as normal fat cells
  • some individuals have familial lipoma syndrome, an autosomal dominant trait appearing in early adulthood where an individual may have hundreds of lipomas
58
Q
  • plaques with silver scaling are characteristic of?
A
  • psoriasis
59
Q

Most common type of psoriasis?

A
  • plaque psoriasis
60
Q

Relationship of urticaria and angioedema?

A
  • you will commonly see urticaria w/o angioedema

- but you rarely see angioedema w/o urticaria

61
Q

See frightening bullae with positive nikoksky’s sign w/o hx of trauma or burn - what is it most likely? What should you do?

A

pemphigus

- call derm immediately

62
Q

subq vs epidermal characteristics?

A
  • if mass is epidermal (usually a cyst), it is going to feel more fixed
  • if subq - generally mobile