Dermatology Flashcards
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What rare condition can acanthosis Nigricans be a warning sign of?
Gastric adenocarcinoma
What characterizes acne vulgaris?
Open comedones (black heads)
Closed comedones (white heads)
Papules
Pustules
Nodules
Cysts
What are the grades of acne vulgaris?
Grade 1: mild acne (comedones) —> open comedones or blackheads
Grade 2: moderate acne —> greater numbers with occasional papules and pustules
Grade 3: severe acne —> large numbers and pronounced inflammation. Risk of scarring high
Grade 4: cystic acne —> large angry blemishes on face and jawline, can also affect neck arms, shoulders, and back
Closed comedones have ______ blockage
Complete
Treatment of acne vulgaris
Topical retinoids
Cystic acne: tetracyclines then oral retinoids (isotretinoin)
Side effects of isotretinoin?
Dry lips
Liver damage
Increased triglycerides/cholesterol, pregnancy category X
What must you obtain with isotretinoin use?
Pregnancy test
Description of actinic keratosis?
Flesh colored, pink or yellow-brown
sand paper feel
Occurs on sun-exposed surfaces
What is actinic keratosis a precursor to?
Squamous cell carcinoma`=
Treatment of actinic keratosis
Observation
Cryosurgery
5-FU cream
Electrodessication
Imiquimod
Usually removed as precaution
Tinea capitis
Hair loss due to fungal infection of the scalp
What is alopecia areata?
Oval-shaped, well-demarcated hair loss
Usually autoimmune attack against hair follicles
Onset prior to 30 yo
What is traction alopecia?
Hair loss due to pulling force to hair
What is telegenic effluvium?
Thinning or shedding of hair from early entry of hair into telegenic phase
Preceded by psychological or physically stressful event 6-16 weeks prior to hair loss
Growing hairs convert to resting
Appearance of basal cell carcinoma
White waxy lump or brown scaly patch
Raised pearly and rolled borders
Telangiectasias
Central ulcer on sun-exposed areas, such as face and neck
Treatment of basal cell carcinoma
Fluorouracil
Imiquimod
Photodynamic therapy
Surgical excision with clear margins
What is bulbous pemphigoid?
Rare
Chronic acquired autoimmune subdermal blistering skin disorder
Caused by linear deposition of autoantibodies against hemidesmosomes in epidermal-dermal junction
How does bulbous pemphigoid compare to pemphigus vulgaris?
Does not affect mucous membranes
Negative nikolsky sign
More tense, less fragile, and deeper than pemphigus vulgaris
Characteristics of bullous pemphigoid
Large bullae and crusts
Located on axillae, thighs, groin, and abdomen
How is bullous pemphigoid diagnosed?
Skin biopsy with direct immunofluorescence exam showing deposition of IgG and C3 basement membrane
Treatment of bullous pemphigoid
Corticosteroids
What is cellulitis
Acute bacterial skin infection of dermis and subcutaneous tissue
Characteristics of cellulitis
Pain
Erythema
Warmth
Swelling
Margins flat and no well demarcated
Causes of cellulitis in adults
Staphylococcus
Streptococcus
Causes of cellulitis in children
H. Influenza
Strep pneumoniae
Treatment of cellulitis
Mild with MSSA: cephalexin or dicloxacillin
MRSA
Bactrim
Clindamycin
Doxycycline
IV vancomycin or linezolid
Characteristics of condyloma acuminatum
Soft
Skin colored
Fleshy
What types of HPV causes >90% of genital warts
6 and 11
What types of HPV are associated with cervical cancer?
16
18
31
33
35
What subtypes of HPV does the gardasil 9 vaccine protect against?
6, 11, 16, 18, 31, 33, 45, 52, 58
The CDC recommends gardasil-9 starting at what age
11 (can be started at 9)
When do patients need to get only a 2 dose series for HPV?
9-14 years of age
How is condyloma acuminatum diagnosed?
Clinical evaluation
Colposcopy
Anoscopy
Treatment of condyloma acuminatum
Imiquimod
Podofilox
Cryotherapy
Surgery
TCA
Characteristics of contact dermatitis
Well-demarcated erythema
Erosions
Vesicles
What can cause allergic dermatitis?
Type 4 hypersensitivity
Nickel
Poison ivy
What can cause irritant contact dermatitis
Cleaners
Solvents
Detergents
Urine
Feces
Treatment of contact dermatitis
Avoid offending agent
Burrow’s solution
Topical steroids
Zinc oxide
Characteristics of atopic dermatitis
Pruritic
Eczematous lesions
Lichenification
Common on flexor creases
Infant-face and scalp
Adolescent- flexural surfaces
What causes atopic dermatitis
IgE type 1 hypersensitivity
Treatment of atopic dermatitis
Topical corticosteroids and emollients
Topical calcineurin inhibitor
What is nummular eczema?
Coin-shaped/disc-shaped
Treatment of nummular eczema
High or ultra-high potency topical corticosteroids
Characteristics of seborrheic dermatitis
Erythematous
Yellowish greasy scales
Crusted lesions
Infants: scalp (cradle cap)
Adults/adolescents: face, chest, scalp
Treatment of seborrheic dermatitis
Ketoconazole shampoo
Presentation of perioral dermatitis
Young women
Papulopustular
Plaques
Scales around mouth
Treatment of perioral dermatitis
Topical metronidazole
Avoid steroids
What is a drug eruptions
Cutaneous reaction to administration of drug usually within last 6 weeks
Range from mild eruption that resolve when agent removed to severe skin damage with organ involvement
Diagnosis of drug eruptions
Clinical
Treatment of drug eruptions
Monitor for cardiovascular collapse (anaphylaxis)
DRESS (drug rash with eosinophilia and systemic symptoms)
SJS/TEN (extensive bullous reaction/generalized erythroderma)
Withdraw offending agent
If anaphylaxis or widespread urticaria —> epinephrine .2-.5 mg and prednisone to prevent recurrence
Antihistamines
Characteristics of dyshidrosis
Pruritic vesicular eruption
Clear, deep seated vesicles without erythema
On lateral aspects of fingers, central palm, and plantar surfaces
Resembles tapioca pudding
Treatment of dyshidrosis
Petroleum jelly
Moisturizer
Cold compresses
Topical steroids
Characteristics of erysipelas
Well-demarcated, raised, superficial
Lymphatic involvement
Redness and pain
Fevers and chills
What is the most common cause of erysipelas?
Group A strep: strep pyogenes
Treatment of mild erysipelas
Penicillin G
What is erythema multiforme?
Acute, self-limited
Type IV hypersensitivity reaction
Associated with HSV (MC), medications (sulfa drugs) and triggers
Skin lesions associated with erythema multiforme
Extremities (hands, feet, mucosa)
Target-like rash
Raised, blacking, lack of itchiness
What causes erythema infectiosum? (Fifth disease)
Parvovirus B19
Characteristics of erythema infectiosum
Slapped cheek rash on face
Lacy reticular rash on extremities that spares palms and soles
Resolves in 2-3 weeks
Treatment of erythema infectiosum
Supportive
Anti inflammatories
What causes hand foot and mouth disease
Coxsackievirus type A
Characteristics of hand-foot-and mouth disease
Sores in mouth, rash on hands, feet, mouth, and buttocks
Usually clears on own in 10 days
Treatment of hand-foot-and mouth disease
Supportive, anti-inflammatory
Characteristics of measles
4 C’s: cough, coryza, conjunctivitis, and ccephalocaudal spread
Morbilliform - maculopapular, brick red rash on face
Begins at hairline then progresses to palms and soles last
Lasts 7 days
Koplik spots (small red spots on buccal mucosa with blue0white-pale center) precede rash by 24-48 hours
Characteristics of rubella (German measles)
“3 day rash” pink light red spotted maculopapular rash
First on face
Spreads to trunk and extremities
Generalized in 24 hours and lasts 3 days
Posterior cervical and posterior auricular lymphadenopathy
Does not darken or coalesce
How is rubella related to pregnancy
Congenital syndrome
Deafness
TTP
Mental retardation
What causes roseola
Herpesvirus 6 or 7
Characteristics of roseola
Starts on trunk and spreads to face
High fever for 3-5 days, then rose pink maculopapular blanchable rash on trunk/back and face
Characteristics of folliculitis
Papules and pustules
Erythematous, painful but may burn
Common cause of folliculitis
S. Aureus
Pseudomonas in hot tubs
Treatment of folliculitis
Mupirocin ointment and topical benzoyl peroxide
If more extensive: dicloxacillin and cephalexin
If MRSA: bactrim, clindamycin, or doxycycline
What is hidradenitis suppurativa?
Chronic follicular occlusive disease
Recurrent inflammatory nodules, abscesses, sinus tracts, and complex scar formation
Characteristics of hidradenitis suppurativa
Pea to marble sized nodules under skin that can be painful and enlarge and drain pus
Armpits, groin, and buttocks (where skin rubs together)
Treatment of hidradenitis suppurativa
Intralesional triamcinolone
Oral and topical abx
Hygiene
Warm soaks
Sometimes surgery
Characteristics of impetigo
Red sores around nose and mouth
Sores rupture and ooze forming yellow brown crust
“Honey colored” and wheeping
Most common cause of impetigo
S. Aureus
Treatment of impetigo
Mupirocin
Dicloxacillin
Cephalexin
Complication of impetigo
Poststreptococcal glomerulonephritis
Characteristics of kaposi sarcoma
Lesions in skin, lymph nodes, internal organs, and mucous membranes lining mouth, nose, and throat
Purple, red, or brown skin blotches common sign
Tumors may develop in other areas of the body
What is kaposi sarcoma associated with
Human herpesvirus 8 and is AIDS-defining cancer
Treatment of kaposi sarcoma
Radiation or chemotherapy
Rarely, surgery
Characteristics of lice
Pruritic scalp, body, or groin
Nits: small white specs on hair shaft
Diagnosis of lice
Observation of lice and nits
Nits = ovoid, grayish-white eggs
Treatment of lice
Launder fomites such as sheets in hot water (>131 F or 55 C)
Permethrin topical with wet combing
Capitis: shampoo towel-dried hair and wash after 10 mins then repeat in 9 days
pubis/body lice: entire body then washed off after 8-12 hours —> screen for STIs and abstain from sexual contact
Eyelash: ophthalmic grade petroleum jelly BID x 10 days
Lindane = older treatment that can’t be used on infants, children, and elderly due to neurotoxicity
Children can return to school after first application
Resistant cases: oral ivermectin
Treat all family members
What is lichen planus
Chronic papulosquamous inflammatory dermatosis of unknown etiology, possibly autoimmune
Appearance of lichen planus
Purplish
Itchy
Flat topped
Lacy white patches sometimes with painful sores on mucous membranes
5 Ps: purple, papule, polygonal, pruritis, planar
What is wickham striae?
Whitish lines visible in the papules of lichen planus and other dermatoses
Treatment of lichen planus
Topical steroids
What is lichen simplex chronicus
Chronic dermatitis due to chronic repeated rubbing or scratching of skin
Skin thickened with accentuated lines
Characteristics of lichen simplex chronicus
Thick, leathery, brownish skin
Treatment of lichen simplex chronicus
Break itch scratch cycle with anti-histamines and occlusive dressing
What is a lipoma?
Fatty tumor that is generally slow growing and usually harmless
Characteristics of lipoma/epithelial inclusion cyst?
Just under skin and move easily when pressure applied
Common in neck, shoulder, back, abdomen, arms, and thighs
If fast growing: suspect another diagnosis
Treatment of lipoma/epithelial epidermal cyst
Generally not necessary
If bothersome, painful, or growing surgical excision or liposuction
What is an epidermal inclusion cyst?
Epidermis cyst due to implantation of epidermal elements in the dermis
Presentation of epidermal inclusion cysts
Solitary, soft, well defined
Mucin-filled lesions
Painless
Smooth surface and small opening called puncture
Benign
Treatment of epidermal inclusion cyst
Close observation
Surgical management if necessary
What is a melanoma
Pigmented lesion with irregular border, irregular surface, or irregular coloration
Melanocytes become cancerous
Characteristics of melanoma
New, unusual growth
Change in existing mole
Asymmetrical, unevenly pigmented with nodule and irregular border
Asymmetry
Border irregular
Color variability
Diameter increasing or >6
Evolving (change in size, shape, or color)
What is prognosis of melanoma most strongly associated with?
Depth of invasion
