SMB Week 2 Flashcards
Nevis typically appear during what age range?
In the first 3 decades of life
When do seborrheic keratoses typically appear?
During and after the 4th decade of life
A variant of SKs, these are small, hyper pigmented, sessile to filiform, smooth-surfaced papules appearing on the face and temples darker skin types.
Dermatosis Papulosa Nigra
Another name for skin tags
Acrochordons
Complication of removing SKs in darker skinned patients.
Dyspigmentation. Hyper pigmentation with curettage, hypo with liquid nitrogen.
What is the definitive treatment for an inflamed epidermal inclusion cyst?
I & D (but don’t excise due to risk of infection)
Where are melanocytes located?
- In the basal layer of the epidermis
- In the matrix portion of the hair bulb
What is an “epidermal melanin unit?”
A melanocyte together with the 36 keratinocytes it’s dendrites supply.
Two types of melanin:
- Eumelanin
- Pheomelanin
Melanin production is mediated by what enzyme?
Tyrosinase
Variations in skin color are due to what 3 things?
Number, size and aggregation of melanosomes
Which grouping of melanocytes is associated with darker skin, aggregated or non-aggregated?
Non-aggregated
Which form of contact dermatitis is concentration dependent?
Irritant contact dermatitis (ICD)
Which form of contact dermatitis involves papules prior to the formation of vesicles?
Allergic contact dermatitis (ACD)
Which form of contact dermatitis tends to have well-defined borders?
ICD
What are some of the features of chronic ICD?
- Mostly appears on hands
- Hyperkeratosis, scaling and fissures
- Ill-defined borders and lichenification
What type of eczema has “tapioca”-like vesicles?
Dishidrotic eczema
What does the phrase “crescendo reaction” refer to?
The worsening of an allergic reaction with repeated exposure to the antigen
What does the phrase “outside job” refer to when describing contact dermatitis?
Often linear, artificial patterns.
Autoantibodies seen in patients with atopic dermatitis
IgE
Some common triggers of atopic dermatitis
- Food
- Clothing
- Seasons (more common in winter)
- Emotional stress
Most common symptom of atopic dermatitis
Itching (it’s often described as “the itch that rashes”)
Type of vesicular eczema seen on the hands and feet
Dishidrotic eczema
Treatment for ICD
- Removal of irritant
- Wet dressings with Burow’s solution
- Topical glucocorticoids
Treatment for atopic dermatitis
- Hydroxyzine or oral antihistamine for itching
- Topical glucocorticoids
- Topical Mupirocin for 2-ary infection
Treatment for lichen simplex
- Topical glucocorticoids or tar preparations with occlusive dressing
- Unna boot
Treatment for nummular eczema
- Moisturizing cream
- Topical glucocorticoids
- Coal tar ointment
- UVB light therapy
Treatment for dishidrotic eczema
- Topical corticosteroids for small areas
- Prednisone for serious cases
Treatment for asteatotic dermatitis
- Medium potency glucocorticoids
- Emollients
- Avoid soapy baths
- Humidify room
What the average thickness of skin?
1.5 - 4 mm
What are some of the reasons for the increased incidence of non-melanoma skin cancer?
- Aging population
- Increased awareness
- Increased leisure time
Etiology of basal cell carcinoma
- Hedgehog pathway: loss of inhibition of cell growth
- P53 pathway: tumor suppressor genes inactivated
Etiology of squamous cell carcinoma
- P53 pathway: tumor suppressor genes inactivated
Most common cancer
Basal cell carcinoma
Typical appearance of basal cell carcinoma
- Waxy, pearly, papule
- May be umbilicated with crust
- Rolled border, telangiectasias
- Common on face and periorbital region
Dx of basal cell carcinoma
Biopsy
Typical appearance of squamous cell carcinoma
- Small, firm, skin-colored to pink papules or plaques
- Often crusty
- Common with transplant pts
- Common in areas of prior trauma (scars, burns, etc.)
Which type of skin cancer is least likely to metastasize?
BCC
Squamous cell carcinoma in situ is known as:
Bowen’s disease
Skin cancer common on lower legs of women
Bowen’s disease
Treatment for actinic keratoses
- Liquid nitrogen
- Topical chemotherapy (5-fluorouracil)
- Imiquimod (immunomodulator)
- Ingenol mebutate (plant substance that induces cell death)
- Lasers or CO2 resurfacing
Rare slow-growing tumor found in anogenital region. May arise from apocrine glands or keratinocytic stem cells.
Extra-mammary Paget’s disease
What is EMPD sometimes misdiagnoses as?
Eczema or similar disease
Tissue preserving surgical method for treating non-melanoma skin cancer:
Mohs Micrographic Surgery
Oral medication blocking hedgehog pathway, used to treat non-melanoma skin cancer
Vismodegib
Indications for Mohs micrographic surgery:
- Large size
- Facial location
- Aggressive histology
- Ill defined borders
- Immunosuppressed
Papulosquamous vs eczematous conditions:
Papulosquamous:
- Papules and plaques
- Little to no crust, erosion, vesicles
- Sharply demarcated
Eczematous:
- Plaques
- Erosions, crust, excoriations, vesicles
- Not well-demarcated
Things that can worsen psoriasis:
- Alcohol abuse
- Smoking
- Obesity
- Stress
- Strep throat
- Cold weather
- Medication changes
- Koebner
True or false: People with severe psoriasis are at an increased risk of MI
True
What makes someone a good candidate for systemic treatment of psoriasis?
- BSA > 5%
- Failure of local therapy or poor quality of life
- Vulnerable area involvement
- Concomitant arthritis
Topical treatments for psoriasis:
- Corticosteroids
- Calcineurin inhibitors
Systemic tx for psoriasis:
Older:
- Methotrexate, cyclosporine, acitretin, UV light therapy
Newer:
- Biologics
Etiology of pityriasis rosea:
HHV 6 and 7
Treatment for lichen planus
- Topical corticosteroids, IL steroids, tacrolimus
- Systemic steroids, acitrenin, antimalarials
Etiology of mycosis fungoides
Type of cutaneous T cell lymphoma
Etiology of lichen planus
Unknown. Probably autoimmune.
Sezary syndrome, seen with mycosis fungoides:
erythroderma, LAD, atypical lymphocytes in skin and blood
Dx of lichen planus
- epidermal hyperplasia
- band like lymphcytic infiltrate in dermis
Presents with violaceous, flat topped, polygonal papules, wickham striae, and can result in scarring alopecia and nail destruction.
Lichen planus
Treatment for pityriasis rosea
Self-limiting. Treat symptomatically with:
- antihistamines
- UVB
- topical steroids
Self-limiting disease that presents with a herald patch and a christmas tree distribution
Pityriasis rosea
Typical distribution of lichen planus
- Trunk and extremities (flexural wrists, ankles)
- Oral and genital
True or false: melanomas typically start from existing nevi.
False: only about half start from existing nevi.
Melanoma in situ:
- confined to epidermis
- tends to occur on face in older puts
Newer prognostic test for melanoma invasiveness
Sentinel node biopsy
Amelanotic melanoma
Melanoma that affects non-melanin producing melanocytes
ABCDE’s of melanoma
- Asymmetric
- Border
- Color
- Diameter (> 6mm)
- Evolution
Some risk factors for melanoma
- Red or blond hair
- 3 or more blistering sunburns before age 20
- 3 or more outdoor summer jobs before age 20
- Family Hx
- Hx of NMSC
The single most important factor in melanoma survival:
Depth of invasion
What’s the next most important factor in melanoma survival?
Ulceration
The most common skin cancer in whites:
BCC
The most common skin cancer in blacks:
SCC
In non-whites, melanoma arises most often in which areas?
Non-sun exposed areas
In whites, melanoma arises most often in which areas?
Sun-exposed areas
DRESS
Drug Rash with Eosinophilia and Systemic Symptoms:
- Later onset than most drug eruptions
- Facial edema, blisters
- Systemic Sx
- Tx with systemic or topical steroids
Common causes of fixed drug eruptions
- Tetracyclines
- Sulfa
- NSAIDS
- barbiturates
- phenylphthalein
Erythema Multiforme
- Target lesions on acral extremities, palms/soles
- Associated with HSV
- No giant multinucleated cells
- Acyclovir 400 mg bid prophylaxis
- Topical steroid Tx
Antibodies seen with pemphigus and pemphigoid
IgG
Histologically, the hallmark of blistering diseases like pemphigus and pemphigoid.
Acantholysis (loss of intercellular connections, i.e., the chicken wire)
True or false: Nikolsky’s sign is present in bullous pemphigoid
False: blisters do not spread with pressure
Age of onset for bullous pemphigoid:
Usually after age 60
Age of onset for pemphigus vulgaris
Usually in 50’s
Clinical presentation of pemphigus vulgaris as opposed to bullous pemphigoid:
BP: - Later onset (> age 60) - Less mucosal involvement (10%) - Bullae PV: - Mucosal involvement (usually starts in mouth) - May see erosions instead of bullae - Earlier onset (50's)
Tx for bullous pemphigoid and pemphigus vulgaris:
- Prednisone
- Azathioprine or mycophenolate
- Retuximab
- Methotrexate
- Abx for 2-ary infections
(not a complete list)
What mutation is seen in atopic dermatitis?
Filaggrin gene
Maintenance control of atopic dermatitis:
- Topical steroids 2x/week
- Steroids 2x/week + Calcineurin 3x/week
Pt education about calcineurin inhibitors:
- May cause burning/stinging
- Safe around eyes, mouth, genitals
- Works best on thin skin
- Use sunscreen (skin cancer risk)
Causative bacteria in acne:
propionibacterium acnes
Pt education for spironolactone for acne treatment:
- Will lower BP
- Diuretic
- Potassium sparing, so no potassium supplements
- Need to stay on it for 3 months for results
Topical treatments for rosacea:
- Azaleic acid
- Metrocream or gel
- Sodium sulfacetamide
Treatment of perioral dermatitis:
- Metrogel
- Clindamycin
- Doxycycline
- Protopic or Elidel
Mnemonic for therapy for bullous pemphigoid:
PT Doesn’t Do Mixed Martial Arts:
- Prednisone
- Tetracyclines
- Dapsone
- Dermatology consult
- Methotrexate
- Mycophenolate or Azathioprine
Mnemonic for therapy for pemphigus vulgaris:
MR. DAMP
- Methotrexate
- Rituximab
- Dermatology consult
- Azathioprine
- Mycophenolate
- Prednisone
Types of urticaria:
- Acute: IgE mediated Type 1 rxn
- Chronic: Auto IgG against Fce mast cell receptors
- Physical: pressure, solar, vibratory, cold, hot
- Others: direct mast cell binding by substances
Options for systemic Tx of atopic dermatitis:
- Immunosuppressants: Prednisone, Azathioprine/Mycophenolate, Cyclosporine, FK=506 (Tacrolimus)
- Immunomodulators: Methotrexate, interferon gamma
- Anti-inflammatory drugs: antihistamines, leukotriene inhibitors, anti-IgE
True or false: Atopic dermatitis is an IgE mediated condition
False: It’s a skin disease with allergies, not an allergic skin disease.
Potency classes for topical steroids are based on what?
The ability to vasoconstrict.
General principles for topical steroid application:
- Start with more potent and move to less
- bid application is sufficient
- Use non-fluorinated on face and intertrigenous areas
- High potency over thick skin (knees, elbows, feet)
- Low potency over thin skin (face, axilla, groin)
