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Flashcards in Derm Deck (132)
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1
Q

Describe 10 questions of the dermatologic history

A
  1. Onset (primary lesion, timing)
  2. Pattern of spread
  3. Symptoms
  4. Treatments
  5. Medications & allergies
  6. PMH of skin, other
  7. FH for skin conditions
  8. Work/hobby contactants (including pets)
  9. Recent travel/exposures
  10. Sexual history
2
Q

Describe the 5 components of the dermatologic physical exam

A
  1. Type of lesion; primary/secondary/special
  2. Distribution
  3. Configuration
  4. Color
  5. Epidermal (surface change) or dermal (no surface change)
3
Q

What is the Koebner phenomenon?

A

Refers to skin lesions appearing on lines of trauma, e.g. psoriasis appearing at biopsy site or area of sunburn

4
Q

What is the Auspitz sign?

A

the appearance of punctate (pinpoint) bleeding spots when psoriasis scales are scraped off

5
Q

What is the id reaction?

A

In an id reaction, ERYTHEMATOUS VESICLES usually are seen on the lateral aspects of the fingers and the palms and are typically PRURITIC. This eruption of vesicles is usually sudden and classically occurs in response to an intense inflammatory process, especially FUNGAL infections (e.g. tinea pedis), taking place SOMEWHERE ELSE on the body. Treatment of the underlying infection results in resolution.

6
Q

What is the Nikolsky sign?

A

A clinical dermatological sign, when slight rubbing of the skin results in exfoliation of the outermost layer, forming a blister within minutes.

Nikolsky’s sign is almost always present in toxic epidermal necrolysis (TEN) and is associated with pemphigus vulgaris. It is useful in differentiating between pemphigus vulgaris (where it is present) and bullous pemphigoid (where it is absent).

7
Q

Describe the system for classifying skin phototypes.

A

I - white, very fair, red or blond, blue eyes, freckles
always burns, never tans

II - white, fair, red or blond, blue, hazel, or green eyes
usually burns, tans with difficulty

III - cream white, fair with any eye or hair color, very common
sometimes mild burn, gradually tan

IV - brown, typical Mediterranean caucasian skin
rarely burns, tans with ease

V - dark brown, mideastern skin types
very rarely burns, tans very easily

VI - black
never burns, tans very easily

8
Q

Name and describe the three stages of hair growth.

A

Anagen - growth; 85% of hair, rapidly dividing
average 3 years
beard, scalp - long anagen
eyebrows, pubic - short anagen

Catagen - regression; apoptosis-driven, 3% of hair
3 weeks

Telogen - resting; 10-15% of hairs
about 3 months
extremities, eyebrow, pubic/axillary - long telogen

9
Q

Differences between MSSA and MRSA cellulitis

Drugs to treat each

A

MRSA is a more effective colonizer; has higher rates of adverse outcomes and treatment failure; has higher cost of care

MRSA: Clindamycin, TMP-SMZ, Vancomycin

MSSA: Cephalexin, dicloxacillin

10
Q

Name the organism(s) associated with impetigo

A

S. aureus, GAS

11
Q

Name the organism(s) associated with erysipelas

A

GAS

12
Q

Name the organism(s) associated with cellulitis

A

S. aureus, GAS

13
Q

Name the organism(s) associated with erythrasma

A

Corynebacterium minutissimum

14
Q

Name the organism(s) associated with necrotizing fasciitis

A

GAS, S. aureus, Clostridium, polybacterial

15
Q

Name the organism(s) associated with pitted keratolysis

A

Kytococcus sedentarius

16
Q

Name the organism(s) associated with tinea capitis, barbae, corporis, unguium, cruris, pedis

A

tinea pedis: Trichophyton rubrum
tinea capitis: Trichophyton tonsurans
tinea corporis: T. rubrum; M. canis
tinea cruris: T. rubrum; T. mentagrophytes
tinea barbae: T. verrucosum; T. mentagrophytes
tinea unguium: T. rubrum; T. mentagrophytes

17
Q

Name the organism(s) associated with tinea versicolor

A

Malassezia (tinea versicolor is not a true tinea….more accurate name is pityriasis versicolor)

18
Q

Name the organism(s) associated with candidiasis

A

yeast, C. albicans

19
Q

Name the organism(s) associated with molluscum contagiosum

A

poxvirus

20
Q

Name the organism(s) associated with verrucae

A

HPV

21
Q

KOH - method and findings

A

scraping + slide + drop of KOH + microscope

looking for fungal hyphae; “spaghetti & meatballs”

22
Q

diascopy - purpose and technique

A

to check for blanching: clear slide + press against lesion and observe through slide

23
Q

viral culture - key points

A
  • Take a sample by rubbing a sterile swab on the lesion
    · Must include cells not just fluid from the blister
    · Optimal if removed during the acute (worse) phase
    · highly dependent on appropriate selection, collection, and handling of biological specimens.
    · When delays are expected, viral samples should be refrigerated at 4⁰C
24
Q

fungal culture - key points

A

May be done after a KOH prep
Results may take weeks
Limited application
Samples easily contaminated by bacteria

25
Q

acetowhitening

  • -purpose
  • -indications
  • -collection procedure
  • -clinical use
A

Purpose: to identify areas of squamous cell change

Indications: abnormal Pap or HPV test; abnormal cervix appearance; abnormal bleeding

Collection procedure: during colposcopy, apply acetic acid solution to cervical area of concern; biopsy areas of whitened cells (abnormal) and study histologically

Clinical use: diagnose cervical dysplasia, HPV

26
Q

Gram stain

  • -purpose
  • -procedure
  • -interpretation
A

Purpose: to differentiate between Gram-negative and Gram-positive bacteria; to visualize morphological bacterial features

Procedure:

  1. specimen on slide
  2. apply crystal violet, rinse
  3. apply iodine, rinse
  4. apply decolorant, rinse
  5. apply counterstain (safranin red), rinse

Interpretation: Gram-positive = dark purple or blue, Gram-negative = pink/red

27
Q
Wood's light
What are the clinical interpretations of interest?
Erythrasma
Pseudomonas
Tinea capitis
Tinea versicolor
Pigmented lesions of the epidermis
Pigmented lesions of the dermis
Vitiligo
False positives
A

Erythrasma: coral pink

Pseudomonas: green

Tinea capitis: T. tonsurans does not fluoresce; Microsporum fluoresces bright green

Tinea versicolor: orange-yellow

Pigmented lesions of the epidermis: accentuated

Pigmented lesions of the dermis: faded

Vitiligo: white

False positives: scale, soap, fibers, ointments, scars

28
Q

bacterial (wound) culture
Specimen must contain:
What are the indicative factors about the growth conditions in the lab?

A

Specimen must contain exudate and/or necrotic tissue!

Much can be learned from the medium on which growth takes place/doesn’t occur, as well as the oxygen availability

29
Q

herpes serology
Purpose
Indications

A

Purpose: Designed to detect an antibody response in serum samples after an exposure; To distinguish between two serotypes; HSV 1 (oral) and HSV 2 (genital); to enable targeted treatment with appropriate antivirals

Indications: PE findings e.g. vesicles, pustules, shallow ulcers with erythematous base; recent exposure; pregnant women

30
Q

Tzanck smear
Purpose
Technique
Findings

A

A Tzanck smear is a cytologic technique most often used in the diagnosis of herpesvirus infections (HSV or VZV). An early vesicle, not a pustule or crusted lesion, is unroofed, and the base of the lesion is scraped gently with a scalpel blade. The material is placed on a glass slide, air-dried, and stained with Giemsa or Wright’s stain. MULTINUCLEATED EPITHELIAL GIANT CELLS suggest the presence of HSV or VZV; culture or immunofluorescence, or genetic testing must be performed to identify the specific virus.

31
Q
melanoma
main risk factors?
what is the number one indicator of prognosis?
what is the ugly duckling sign?
what are 3 factors of assessment?
What is the ABCDE assessment?
A

Main risk factors: UVR; > 100 nevi; skin phototype I or II

The number one indicator of prognosis is thickness of lesion/tumor. Thicker is bad.

Ugly duckling sign: one mole stands out as different-looking amongst a field of moles

3 assessments: dermoscopy by an experienced clinician; excision with NARROW margins (to preserve tissue for later excisional surgery); histological assessment by an experienced dermatopathologist

ABCDE:
Asymmetry
Border
Color
Diameter
Elevation/Evolving
32
Q

Mohs micrographic surgery

  1. What are the benefits?
  2. What kind of cancer is it the most effective in curing?
  3. What other cancers is it used for?
A
  1. High cure rate with lowest cosmetic issues
  2. Highest cure rates for BCC; slightly less with SCC
  3. May be used for some melanoma as well
33
Q

What is the difference between eczema and dermatitis?

A

The terms eczema and dermatitis are used interchangeably, denoting a polymorphic inflammatory reaction pattern involving the epidermis and dermis. There are many etiologies and a wide range of clinical findings. Acute eczema/dermatitis is characterized by pruritus, erythema, and vesiculation; chronic eczema/dermatitis, by pruritus, xerosis, lichenification, hyperkeratosis, ± fissuring.

34
Q

Name 6 general treatments for psoriasis.

A
  1. emollients/keratolytics
  2. corticosteroids
  3. coal tar
  4. phototherapy
  5. methotrexate
  6. cyclosporine
35
Q

Name 5 adverse side effects of topical steroids.

A
  1. HPA suppression
  2. dermatitis
  3. hypopigmentation
  4. skin atrophy
  5. striae
36
Q

Describe asteatotic dermatitis

A

A common pruritic dermatitis that occurs especially in OLDER persons, in the winter in temperate climates—related to the low humidity of heated houses.
—The sites of predilection are the legs, arms, and hands but also the trunk.
—Dry, “cracked,” superficially fissured skin with slight scaling.
—The incessant pruritus can lead to LICHENIFICATION, which can even persist when the environmental conditions have been corrected.
—The disorder results from too frequent bathing in hot soapy baths or showers and/or in older persons living in rooms with a high environmental temperature and low relative humidity.

37
Q

What condition is described as “dew drops on a rose petal” presentation?

A

Herpes simplex (grouped vesicles on an erythematous base)

38
Q

What do you think if you hear “rodent ulceration”?

A

Basal cell carcinoma

39
Q

What do you think if you hear “umbilicated”?

A

molluscum contagiosum

40
Q

What is a classic diagnostic sign for warts?

A

black dots (thrombosed capillaries)

41
Q

What is a side effect risk of cryotherapy (e.g. liquid nitrogen)?

A

hypopigmentation, hyperpigmentation

42
Q

What are three treatments for warts?

A

freezing, salicylic acid, duct tape

43
Q

If you see comedones you know it’s _____

A

acne

44
Q

What are the TOPICAL treatments for acne?

A

benzoyl peroxide
retinoids
topical ABX
keratolytics/salicylic acid

45
Q

What are the SYSTEMIC treatments for acne?

A

oral antibiotics (doxycycline, minocycline)
isotretinoin
intralesional steroids
OCPs

46
Q

Differences between acne vulgaris and rosacea:
distribution
comedones

A

acne vulgaris: face/trunk
rosacea: cheeks/chin, forehead/nose

comedones: MUST have for acne vulgaris; do NOT have in rosacea

47
Q

How much mass is a fingertip unit?

A

1 FTU = 0.5 g

48
Q
Which is least drying? Which is most drying?
powder
cream
lotion
tincture
gel
ointment
A

LEAST DRYING (best for conditions like eczema): OINTMENT

CREAM is the next most emollient/least drying

LOTION

GELs can be drying (depends on alcohol content)

TINCTURES are drying (the purpose of a tincture is to dry)

POWDER

49
Q
Define
ointment
cream
lotion
gel
tincture
powder
A

ointment: homogeneous, greasy, semi-solid; no surfactant or detergent. E.g. Vaseline, triamcinolone

cream/lotion: These are emulsions with oils and water and include a surfactant so the two will mix together. They can contain preservatives, humectants and stabilizers as well (which can be irritants). They need to be rubbed in, and therefore can be drying. Cream is a more solid form, while a lotion is a more liquid form. The more liquid it is, the more drying it will be.

gel: Non-greasy mixtures of propylene glycol and water (can contain alcohol). They have a translucent appearance and are sticky.
Gels with alcohol are best for acute exudative lesions (poison ivy dermatitis)
Alcohol-free gels should be used for dry and scaling conditions.

tincture: plant or animal extract in alcohol
powder: powdered drug, or drug mixed with a delivery powder such as corn starch. Good for intertriginous areas to dry them (e.g. axilla, inguinal)

50
Q

What is the MOA of topical corticosteroids? How is potency determined?

A

MOA: anti-inflammatory, inhibit cell division, cause vasoconstriction

Potency is determined by ability to vasoconstrict

51
Q

What is the lowest potency topical corticosteroid?
What are the intermediate potency topical corticosteroids? (4)
What are the highest potency topical corticosteroids? (3)
What classes are the highest potency and the lowest potency?

A

lowest: hydrocortisone
intermediate: triamcinolone, fluocinolone, halcinonide, mometasone
highest: betamethasone, clobetasol, halobetasol

Class I is the highest potency; class VII is the lowest potency.

52
Q

What is tachyphylaxis?

A

Defined as the decrease in drug response when used over a prolonged period of time, tachyphylaxis is commonly observed during corticosteroid topical therapy. It is now thought that decreased adherence may be a contributing factor, rather than loss of corticosteroid receptor function. Increase in adherence may be achieved by asking patients to use it only on weekends (weekend therapy) or specific days of the week (pulse therapy).

53
Q

Name 5 factors that increase absorption of topical corticosteroids (or any topical drug).

A
  • -Thin skin location e.g. eyelids
  • -Wet skin
  • -Occlusion (e.g. plastic wrap, but includes intertriginous areas)
  • -Greasy ointment base
  • -Rubbing it in
54
Q
We already know that a fingertip unit is 0.5 g. 
How many grams of topical preparation are needed for a single application on:
face
scalp
arm
hand (both sides)
one side of trunk
one leg + foot
anogenital area
whole body
A

From Fitzpatrick table 214-1:

face: 1 g
scalp: 2 g
arm: 3 g
hand (both sides): 1 g
one side of trunk: 4 g
one leg + foot: 5 g
anogenital area: 1 g
whole body: 30 - 40 g

Or: 
1 g for face, hand, anogenital area
2 g for scalp
3 g for arm
4 g for one side of trunk
5 g for one leg + foot
30-40 g for whole body
55
Q
topical liquid nitrogen
indications
contraindications
3 techniques
adverse effects
A

indications: skin neoplasms
contraindications: lesions that require histopathology! cold intolerance, cold urticaria, lesions with indistinct borders, darkly pigmented melanomas

3 techniques: open spray, closed, dipstick

adverse effects: nerve damage, scarring, hypopigmentation, pain, alopecia

56
Q

Disorders for which to give highest potency topical corticosteroids: (5)

A
psoriasis
lichen simplex chronic
severe eczema
severe poison oak/ivy
alopecia areata
57
Q

Disorders for which to give medium potency topical steroids: (5)

A
atopic dermatitis
nummular eczema
asteatotic eczema
scabies (after scabicide)
contact dermatitis
58
Q

Disorders for which to give low potency topical steroids: (5)

A
diaper dermatitis
facial dermatitis
anal dermatitis
eyelid dermatitis
intertrigo
59
Q

If you see peau d’orange, what do you think of?

A

erysipelas

60
Q

Describe the staging of decubitus ulcers.

A

Stage I: nonblanchable erythema of intact skin

Stage II: partial thickness skin loss involving epidermis and may include dermis

Stage III: Full-thickness skin loss involving damage or necrosis of subcutaneous tissue that may extend to, but not through, underlying fascia

Stage IV: Full-thickness skin loss with extensive necrosis of or damage to muscle, bone, or supporting structures

61
Q

What do you think if you see pruritic, clear, “tapioca-like” vesicles along finger edges?

A

Dyshidrotic eczema

62
Q

Name 2 disorders you may use Burrow’s solution/dressing on.

A

Dyshidrotic eczema, contact dermatitis

63
Q

What is the allergic triad associated with atopic dermatitis?

A

asthma, eczema, allergic rhinitis

64
Q

Lichenification is a characteristic feature of _____

A

atopic dermatitis

65
Q

Dyshidrotic eczema topical glucocorticoid treatment:

A

high potency with plastic occlusive dressing for 1-2 weeks

66
Q

Describe nummular eczema and its treatments.

A

Well-demarcated coin-shaped plaques. Chronic plaques are dry, scaly, and lichenified. Topical steroids in the mid- to high-potency range are the mainstay of treatment. The calcineurin inhibitors, tacrolimus and pimecrolimus, and tar preparations are also effective.

67
Q

What is xerosis?

A

dry skin

68
Q

Solar lentigo

A

Circumscribed pigmented macules occurring singly or as multiple lesions and present on the skin surface exposed to UVR. Also known as sun-induced freckles, liver spots, senile lentigo.

69
Q

Miliaria

A

Miliaria results from disruption of sweat ductal integrity with consequent sweat secretion into layers of the epidermis. Ultraviolet light exposure, resident organisms on skin, and repeated sweating episodes are facilitating factors. Focal anhidrosis can occur and persist for several weeks, much longer than the miliaria in affected skin regions.

70
Q

Dermatoheliosis

A

photoaging

Persons with skin phototype I and II are most susceptible.

The skin is waxy, deeply wrinkled, and dry.

Higher risk of skin cancer is indicated.

71
Q

Polymorphous light eruption

A

Polymorphous light eruption is a term that describes a group of heterogeneous, idiopathic, acquired, acute recurrent eruptions characterized by DELAYED (within hours; lasts for 7-10 days) abnormal reactions to UVR.
Pruritis and paresthesias.

72
Q

Porphyrias (hetergeneous group of heme metabolism disorders)

A

Metabolic Photosensitivity
Chemical induced or genetic
Adult onset

  • “Fragile Skin” from painful erosions
  • Tense bullae on hands and feet based on sun exposure
  • Gradual onset
  • Urine sample: red/pink fluorescence of urine
73
Q

Folliculitis
most common organisms
treatment
variants

A

A pustule at a follicular opening represents folliculitis. Deeper follicular infections are called furuncles (single follicle) and carbuncles (multiple follicles). Staphylococci and streptococci are the most frequent pathogens.
Treatment consists of measures to remove follicular obstruction—either cool, wet compresses for 24 hours or keratolytics such as those used for acne. Topical or oral anti-staphylococcal antibiotics may be required.

74
Q

pseudomonas folliculitis

A

Also known as “hot tub” folliculitis; arises hours to days after bathing in inadequately disinfected warm water. Result is eruption of scattered small red itchy or tender bumps, some may be pustular. Bacteria often associated with is Pseudomonas aeruginosa. Tx: Mild cases resolve on their own; severe can be treated with systemic antibiotics against gram negative bacteria

75
Q

Pseudofolliculitis barbae

A

“Shaving bumps” or “razor rash”; a type of folliculitis; a foreign-body inflammatory reaction surrounding ingrown facial hair which results from shaving. Occurs more commonly in people with curly hair. Tx: let beard grow for 30 days to eliminate ingrown hairs. Use moisturizing shaving foam. Use a single blade razor when shaving resumed (double blade razor cut hairs too short, allowing them to grow in). Alternatively use electric shaver. Rx: Tetracycline or similar.

76
Q

Beau’s lines are associated with ____

Pitted nails are associated with ____

A

telogen effluvium

psoriasis

77
Q

4 differences between bullous pemphigoid and pemphigus vulgaris

A
  1. bullous pemphigoid is pruritic; p.v. is not
  2. bullous pemphigoid the bullae will be present; p.v. the bullae have all broken open and will not be present anymore
  3. bullous pemphigoid is not usually fatal; p.v. is serious and can be deadly
  4. bullous pemphigod = negative Nikolsky sign; p.v. = positive Nikolsky sign
78
Q

Hidradentitis suppurativa

A

A chronic, suppurative, often cicatricial disease of APOCRINE gland–bearing skin.
Involves the axillae, the anogenital region.
May be associated with severe nodulocystic acne and pilonidal sinuses (termed follicular occlusion syndrome).
MANY BLACK COMEDONES, some of which are paired, are a characteristic finding, associated with deep, exquisitely painful abscesses and old scars.

79
Q
Rosacea
appearance
distribution
how to differentiate from acne vulgaris
treatment
A

INCREASED CAPILLARY ACTIVITY

Persistent erythema, telangiectases, papules, pustules; rhinophyma

Commonly distributed symmetrically on the face (cheeks, chin, forehead, glabella and nose)

NO COMEDONES

tetracyclines

80
Q

Name 2 treatments for hyperhidrosis.

A
  1. Mild cases of axillary and palmar sweating are controlled via topical application of aluminum chloride.
  2. Iontophoresis
81
Q

Perioral dermatitis is strongly associated with ____.

Appearance:

Treatment:

A

Misuse/overuse of topical corticosteroids!

The primary lesions of perioral dermatitis are discrete and grouped erythematous papules, vesicles, and pustules. The lesions are often symmetric but may be unilateral and appear in the perioral, perinasal, and/or periocular regions.

If topical corticosteroids are being used, they should be discontinued. In most cases, effective therapy is oral tetracycline, doxycycline, or minocycline.

82
Q

Acne vulgaris treatments for mild, moderate, and severe:

A

Mild acne:
Topical antibiotics (clindamycin and erythromycin)
Benzoyl peroxide gels
Topical retinoids

Moderate acne:
Oral antibiotics are added to the above regimen, intralesional triamcinolone

Severe acne:
Systemic treatment with isotretinoin

83
Q

What is acne conglobata?

A

Severe cystic acne with more involvement of the trunk than the face. Coalescing nodules, cysts, abscesses, and ulceration; occurs also on buttocks.

84
Q

Renal transplant is associated with:

A

sebaceous hyperplasia

85
Q

10-15% of people using cyclosporine develop:

A

sebaceous hyperplasia

86
Q

What does sebaceous hyperplasia look like in newborns? In older people?

A

Newborns: Prominent white to yellow papules at the opening of pilosebaceous follicles without surrounding erythema—especially over the nose

Older adults: lesions are 1 to 3 mm in diameter and have both telangiectasia and central umbilication

87
Q

Stasis dermatitis is a finding of chronic ____ disease

A

venous

88
Q

What does stasis dermatitis look like?

Where does it typically occur?

A

It is characterized by erythema, scaling, pruritus, erosions, oozing, crusting, and occasional vesicles may occur during any stage of chronic venous insufficiency. Over time, lesions may lichenify.
It typically occurs in the medial supramalleolar region where microangiopathy is most intense.

89
Q

Describe the appearance of thrombocytopenic purpura.

Who gets it?

A

Thrombocytopenic purpura is characterized by cutaneous hemorrhages occurring in association with a reduced platelet count.
Hemorrhages are usually small (petechiae) but at times larger (ecchymoses).
Occur at sites of minor trauma/pressure (platelet count < 40,000/L) or spontaneously (platelet count < 10,000/L)

Acute idiopathic thrombocytopenic purpura mostly in children; drug-induced and autoimmune TP in adults.

90
Q

What is livedo reticularis?

A

purple lace-like pattern on lower extremities, sometimes seen in vasculitis

91
Q

If you see a herald patch and a christmas tree distribution, what is it?

A

Pityriasis rosea

92
Q
Pityriasis rosea
What causes it?
Who usually gets it?
What does it look like?
Treatment?
A

viral etiology (a herpesvirus?)

Most commonly affects young adults

Asymptomatic, Oval brown-colored plaques up to 2 cm in diameter sometimes accompanied with mild itching

Self-resolving

93
Q

Seborrheic dermatitis
appearance
treatment

A

“Greasy scale”. Dry scales with underlying erythema is found on scalp, face ( in a T distribution across the forehead and down the nasal bridge), chest, back, umbilicus, eyelids and body folds

Shampoos with zinc or selenium are used for scalp seborrhea. Tar shampoos can also be used of milder cases. Low-potency corticosteroid creams are applied in non-scalp areas and topical steroid-sparing alternatives are offered (protopic and elidel).

94
Q

What are the 4 P’s of lichen planus?

Treatment?

Typical age of onset?

A

Purple, pruritic, polygonal, papules

Treat with high potency topical steroids

Age 30-60

Can Koebnerize

95
Q

Icthyosis
Describe
Causes? Age of onset?
Treatment?

A

describes a group of hereditary disorders characterized by an excess accumulation of cutaneous scale, varying from very mild and asymptomatic to life threatening.

Usually genetic, so starts at birth

Hydration and lubrication of the skin

96
Q
Dermatofibroma
appearance
cause
Telltale sign
Treatment
A

3-10mm in diameter, domed but sometimes depressed.
Surface dull, shiny or scaly. Firm
Color: skin-colored, pink, brown, or dark chocolate brown.
Borders ill-defined.
Rarely tender.

Usually a reaction to an arthropod bite.

Dimple sign: squeeze on either side and the dermatofibroma inverts/becomes concave

Benign; no treatment necessary

97
Q

Seborrheic keratoses
appearance
treatment

A

Early: 1-3mm barely elevated papule, later a larger plaque.
With or without pigment.
Surface has greasy feel and a hand lens shows FINE STIPPLING (like a thimble)
Late: 1-6cm. Flat nodule
Brown, gray, black, skin-colored. Round or oval.
Plaque w/ warty surface and “stuck on” appearance. Greasy.
Hand lens shows HORN CYSTS – always seen with dermoscopy.

Curettage after slight freezing with cryospray allows histology

98
Q

Pyogenic granuloma

A

Rapidly developing vascular lesion usually following minor trauma that bleeds easily. Papule with a collar of hyperplastic epidermis at the base.

99
Q
Keratoacanthoma
Age of onset
Causes
Appearance & location
3 stages
Treatment
A

Age of onset > 40 years. M:F ratio 2:1.
HPV have been identified in KAs
UV Radiation and chemical carcinogens (pitch, tar)
Variant of squamous cell carcinoma, rapidly growing epithelial tumor. Usually spontaneous regression after 6-12 months w/ scarring.
No symptoms, but occasional tenderness and cosmetic disfigurement.
- sun exposed sites, usually solo but multiple can occur.
3 stages
1) Dome-shaped nodule with central keratotic plug. Firm but not hard. Skin-colored, slightly red, brown. Removal of keratotic plaque results in a crater.
2) Hyperkeratosis replaces most of nodule, thin peripheral tumor tissue.
3) Hyperkeratosis and keratinization replace entire tumor

Tx by excision in early stages because SCC & KA indistinguishable by clinical findings.
Multiple KAs: Systemic retinoids and methotrexate

100
Q
actinic keratosis
causes
signs & symptoms
treatment
strongest predictor of \_\_\_\_
A

Actinic Keratoses develop in response to prolonged exposure to UVR.

AK’s are small (0.2–0.6 cm) macules or papules—flesh-colored, pink, or slightly hyperpigmented—that feel like sandpaper and are tender when the finger is drawn over them
Physical Exam Findings- AK’s are found on sun-exposed areas of the body such as the face, dorsum of hand, neck, forearms.

Treatment methods include cryotherapy, curettage with or without electrosurgery, shave excision, topical agents, and photodynamic therapy

Strongest predictors of subsequent development of nonmelanoma skin cancer and melanoma!

101
Q

dysplastic nevi
describe
Link to skin cancer?

A

Majority of lesions will involute and disappear over time. Normally found in 10% of the Caucasian population.
Signs & Symptoms- Moles are large and >6mm in diameter. Ill-defined, irregular border and irregularly distributed pigmentation. Normally flat or flat with a centrally elevated center.

Patients with 50 or more nevi with one or more atypical moles and one mole at least 8 mm or larger, and patients with few to many definitely atypical moles have an increased risk of melanoma.

102
Q

What group of diseases is known for having a prodromal period? Describe the prodromal symptoms of the most painful & serious version of this group of diseases.

A

Herpesviruses often have prodromal periods.

Herpes zoster
Pain and paresthesia in the involved dermatome often precede the eruption by several days and vary from superficial itching, tingling, or burning to severe, deep, boring, or lancinating pain. The pain may be constant or intermittent and it is often accompanied by tenderness and hyperesthesia of the skin in the involved dermatome.

103
Q

Exanthematous/morbilliform drug reaction

Fixed drug reaction

Describe each; drugs with high probability of reaction

A

Exanthematous drug reaction is a cutaneous eruption that mimics measles.
Usually quite pruritic, disturbs sleep
Drugs with high probability of this reaction: penicillin, sulfas, NSAIDs

A fixed drug eruption (FDE) is an adverse cutaneous reaction to an ingested drug, characterized by the formation of a solitary (but at times multiple) erythematous patch or plaque.
If the patient is rechallenged with the offending drug, the FDE occurs repeatedly at the IDENTICAL skin site (i.e., fixed) within hours of ingestion.
Some high probability drugs: Tetracyclines, sulfas, metronidazole, food coloring

104
Q

Treatments for vitiligo

A

Want to repopulate melanocytes…

  1. UV therapy
  2. Corticosteroids
  3. Calcineurin inhibitor
  4. Psoralen (increases skin’s sensitivity to UVA - “PUVA” therapy - psoralen + UVA)
105
Q

Cause of vitiligo

A

Vitiligo is a multifactorial, polygenic disorder, with a complex pathogenesis that is not yet well understood. Of various theories of disease pathogenesis, the most accepted is that genetic and nongenetic factors interact to influence melanocyte function and survival, eventually leading to AUTOIMMUNE DESTRUCTION OF MELANOCYTES.

106
Q

Describe melasma

A

Macular hyperpigmentation of the face, the hue and intensity depending largely on the skin phototype of the patient. Light or dark brown or even black. Color is usually uniform but may be splotchy. Most often symmetric. Lesions have serrated, irregular, and geographic borders. Two-thirds on central part of the face: cheeks, forehead, nose, upper lip, and chin.

107
Q

Treatments for melasma

A

hydroquinone (skin whitener!)

azelaic acid

108
Q

What causes albinism?
What distinguishes albinism from other pigmentation disorders?
What is piebaldism?

A

Albinism is a recessive trait.

Ocular nystagmus and reduced visual acuity are important features of albinism that distinguish albinism from other congenital disorders of pigmentation.

In albinism there are melanocytes but they don’t function correctly. In other depigmentation disorders there is a lack of melanocytes.

Patients with piebaldism generally have depigmented patches on the ventral or lateral trunk and/or the mid-extremities, sparing the hands and feet. Poliosis (usually present as a white patch of hair) is a common feature.

109
Q

For which skin phototypes is postinflammatory hyperpigmentation a problem?

A

Postinflammatory epidermal melanin hyperpigmentation is a major problem for patients with skin phototypes IV, V, and VI.

110
Q
Describe postinflammatory hyperpigmentation.
What can cause it?
How long does it last?
Treatment?
Lesions?
A

This disfiguring pigmentation can develop with acne, psoriasis, lichen planus, atopic dermatitis, or contact dermatitis or after any type of trauma to the skin. It may persist for weeks to months but does respond to topical hydroquinone, which accelerates its disappearance. Lesions are characteristically limited to the site of the preceding inflammation and have indistinct, feathered borders.

111
Q

What do you think if you see an erythematous, scaly, plaque in a butterfly pattern across the face?

Cause of this disease?

A

Lupus erythematosus - autoimmune

112
Q

What is scleroderma?
What is the facies?
What other condition is almost always present?
What happens with the mouth?

A

Hardening of the skin and internal organs - autoimmune
Mask facies
Raynaud phenomenon
Microstomia

113
Q

Behcet’s syndrome
Cause
Treatment
Describe

A

Behcet’s syndrome is a disease that involves inflammation of the blood vessels. Doctors aren’t sure what causes Behcet’s. There is no cure. Treatment focuses on reducing pain and preventing serious problems.

Painful punched out ulcers erupt in a cyclic fashion in the oral cavity and/or genital mucous membranes. Orodynophagia and oral ulcers may persist/recur weeks to months before other symptoms appear.
Blindness, CNS abnormalities, and thrombosis or rupture of large vessels are the most serious complications

114
Q

Treatments for psoriasis
mild
moderate
severe

A

mild: topical emollients, glucocorticoides, vit D3
moderate: above + phototherapy
severe: above + systemic methotrexate, acitretin, cyclosporine

115
Q

Treatments for atopic dermatitis

A

For cutaneous hydration: warm soaks, occlusive emollients

Tar - antipruritic, anti-inflammatory

Phototherapy

Systemic: cyclosporine, methotrexate

116
Q

Describe the oral dosing for onychomycosis
drug
timing of dosing

A

Itraconazole

“pulse dosing” - 200 mg BID for 1 wk, then 3 weeks off; repeat once

117
Q

What is permethrin used for?

A

5% cream - scabies; leave on for 8-12 hours

1% cream - lice; leave on for 8 hours then rinse

118
Q

What is crotamiton used for?

A

10% cream/lotion - scabies; apply entire body

119
Q

What is lindane used for?

A

shampoo or lotion - lice

may be used for scabies but concerns about toxicity limit it to a single application

120
Q

What are allyamines used for?

A

Topical: tinea pedis, cruris, corporis, tinea versicolor, candidiasis.

Systemic: tinea pedis, cruris, corporis, onychomycosis

121
Q

How can you differentiate between milia and closed comedones?

A

Milia probably won’t have redness

122
Q

Which will blanch and which won’t?
petechiae
telangiectasia

A

petechiae: nonblanching
telangiectasia: blanch

123
Q

Name 3 drugs used to treat scabies.

A
  1. permethrin
  2. crotamiton
  3. lindane
124
Q

Name 2 drugs used to treat lice.

A
  1. permethrin

2. lindane

125
Q

Name 3 drugs used to treat seborrheic dermatitis.

A
  1. selenium sulfide (topical)
  2. ketoconazole
  3. pyrithione zinc shampoo
126
Q

Name 4 drugs used to treat dermatophyte infections.

A
  1. imidazoles - clotrimazole, miconazole, ketoconazole
  2. triazoles - fluconazole, itraconazole
  3. allyamines - terbinafine
  4. griseofulvin
127
Q

What are the differences between cellulitis and erysipelas?

A

Erysipelas: face; RAISED; well-demarcated; peau d’orange

Cellulitis: legs; not raised; poorly demarcated

128
Q

What is cantharidin used to treat?

A

Molluscum contagiosum; verrucae

129
Q

What is the difference in the distribution of irritant contact dermatitis and allergic contact dermatitis?

A

Irrititant contact dermatitis: stays limited to where the irritant contact occurred

Allergic contact dermatitis: may spread beyond where the irritant contact occurred

130
Q

What distinguishes dyshidrotic eczema from plain old atopic dermatitis?

A

Dyshidrotic eczema is a VESICULAR eczema of the fingers, hands, and toes.

131
Q

What skin condition is pre-cancerous (pre-SCC)?

A

Actinic keratosis

132
Q

What skin condition is indistinguishable visually from SCC and must be biopsied to differentiate?

A

keratoacanthoma