Derm Flashcards
(50 cards)
1
Q
Dermatophytes infect what level of the skin?
A
Stratum corneum of epidermis
2
Q
KOH Prep
A
- dissolves keratin and leaves fungal elements
- will show presence of fungal hyphae (does not ID species)
3
Q
Wood’s Lamp
A
- 360 nm wavelength
- Greenish = tinea capitis (microsporum)
- Coral red = erythrasma (C. minutissimum)
- Yellow/gold = tinea versicolor (M. furfur)
- Green = pseudomonas
4
Q
Most common cause of tinea pedis?
A
Trichophyton rubrum
5
Q
Moccasin Tinea Pedis
A
- central clearing with peripheral scaling
- T. Rubrum most common organism
6
Q
Vesicular Tinea Pedis
A
- more aggressive
- sole or instep with clear fluid veicles
- T. Metagrophytes most common organism
7
Q
Id (dermatophytid) reaction
A
- associated with vesicular tinea
- allergic rash caused by an inflammatory tinea infection at a distant site
8
Q
Majocchi’s Granuloma
A
- dermatophyte invades dermis/subQ through hair follicle
- T. Rubrum most common organism
9
Q
Allylamine MOA
A
-inhibit fungal squalene epoxidase
10
Q
Azole MOA
A
-inhibit ergosterol synthesis
11
Q
Most common type of onychomycosis?
A
Distal subungual onycho
12
Q
Distal and lateral subungual onychomycosis
A
- most commonly involves T. Rubrum
- 90% of cases
13
Q
Superficial white onychomycosis
A
-T. Mentagrophytes is most common organism
14
Q
Proximal Subungual Onychomycosis
A
- Caused by T. Rubrum
- Correlation with HIV
15
Q
Best way to dx dermatitis?
A
Punch biopsy
16
Q
Atopic Dermatitis
A
- usually begins in infancy
- itch-scratch cycle
- serum IgE may be elevated (type I hypersensitivity rxn)
- Associated with allergic rhinitis and asthma
17
Q
Contact Dermatitis
A
- Irritant type caused by chemical irritant; non-immunologic; single exposure rxn
- Allergic type caused by allergen; type IV cell mediated hsn rxn; delayed type rxn
18
Q
Dyshydrotic Eczema
A
- AKA Pompholyx
- deep seated pruitic “tapioca” like vesicles (characteristic)
- soles of feet
19
Q
Nummular Eczema
A
- AKA Discoid eczema
- coin-shaped plaques (small papules/vesicles on erythematous base)
- common on lower legs during winter
20
Q
Lichen Simplex Chronicus
A
- Itch-scratch cycle causing circumscribed plaques with lichenification
- Minimal stimulus to skin elicits abnormal pruitic response (hyperexcitability)
21
Q
Seborrheic Dermatitis
A
- AKA cradle cap (infants) and Pityriasis sicca (dandruff)
- Erythema/scaling in areas where sebaceous glands most active (face, scalp, body folds, etc.)
22
Q
Types of Psoriasis based on morphology
A
- Plaque
- Guttate
- Pustular
- Inverse
- Erythrodermic
23
Q
Plaque Psoriasis
A
- most common variant
- extensor surfaces
- Koebner phenomenon: skin dz at sites of skin trauma
- Auspitz sign: pinpoint bleeding after removal of silvery scale
24
Q
Guttate Psoriasis
A
- drop-like
- acute appearance of multiple papule/plaques on proximal extremities and trunk
- *strong association with strep pharyngitis
25
Pustular Psoriasis
- pustules at various stages of development that resolve into hyperpigmented macules
- often limited to palms and soles (can be solitary patch)
26
Psoriatic Erythroderma
-generalized erythema and scaling covering almost entire skin surface
27
Inverse Psoriasis
-erythematous plaques along intertriginous areas
28
Acral/Palmoplantar Psoriasis
- very debilitating form of psoriasis, recalcitrant to therapy
- 80% of cases, hands and feet are ONLY sites involved
29
What are side effects of topical steroids?
- subcutaneous atrophy
- depigmentation (suppressed melanocytes)
- telangectasias
- striae
- tachyphylaxis
- Cushing's
30
Lichen Planus
- purple, polygonal, pruitic, papules
| - Wickham's striae
31
Seborrheic Keratoses
- most common benign cutaneous lesion
- waxy, "stuck on" appearance
- horn cyst (histo hallmark)
32
Keratoacanthoma
- smooth, dome-shaped, red papule with central keratin-filled crater
- typically rapid growth
33
Cutaneous Horn
- hard conical projection of keratin
| - in-situ or SCC often present at base of lesion -> always excise
34
Actinic Keratoses
- AKA solar keratosis
- premalignant lesion of keritinocyte (SCC potential)
- erythematous papule/plaque with coarse scale (sandpaper lesion)
35
Squamous Cell Carcinoma in situ
- AKA Bowens disease
- maculae/papule/plaque that may be scaling or hyperkeratotic
- confined to epidermis
36
SCC
- malignant tumor of keratinocytes
- increased mortality compared to BCC
- most common on sun exposed areas
37
Marjolin's Ulcer
- malignant degeneration to SCC in areas of chronic inflammation, infected, or traumatized skin
- commonly present in chronic wounds
38
BCC
- most common type of skin cancer
| - limited ability to metastasize
39
What does the prognosis of melanoma depend on?
Depth of invasion
40
Clinical presentation of melanoma
- Asymmetry of shape/color
- Border irregularity
- Color variation
- Diameter > 6 mm
- Evolving
41
Growth pattern of melanoma
- Initial radial growth phase: within epidermis, lateral growth, considered in-situ
- Vertical growth phase: growth into dermis with eventual metastasis
42
Melanoma In Situ
- confined to epidermis
| - every melanoma starts in-situ
43
Lentigo Maligna Melanoma
- least common type
| - slowest growing (radial growth lasts 20 years)
44
Superficial Spreading Melanoma
- most common type
| - slow growing (radial growth lasts months to 2 years)
45
Nodular Melanoma
- worst prognosis
| - essentially begins in the vertical growth phase
46
Acral Lentiginous Melanoma
- more common in darker skin patients
- presents on palms, soles, and nails
- radial growth lasts months to years
47
Subungual Acral Lentiginous Melanoma
- melanomas begin in the nail matrix
- present as longitudinal melanonychia
- Hutchinson's sign: spread of pigmentation to proximal or lateral nail fold
48
Amelanotic Melanoma
- forms from melanocytes void of pigment
| - erythematous papules/nodules
49
Clark's Level of Invasion
- Stage 1: epidermis (macule)
- Stage 2: part of the papillary dermis (small papule)
- Stage 3: entire papillary dermis (papule)
- Stage 4: reticular dermis (nodule)
- Stage 5: subcutaneous tissue
50
Breslow's Depth
- 4 mm: 50%
