Dermatology Flashcards
Review sunscreen guidelines.
Apply SPF 30 while outside either every 2 hours and with every water exposure
True or false: fluocinonide 0.05% is a low-medium potency steroid.
False
It is a high-potency steroid.
Compared to seborrheic keratosis, actinic keratosis looks more ____________.
scaly and dry
Seborrheic keratosis looks like a benign mole that is stuck on. Actinic keratosis can be like a raised faint red area (the “felt-more-than-seen” phenotype) or a dry scaly appearance.
When should you biopsy a suspected actinic keratosis lesion?
Any signs of potential transformation to squamous cell carcinoma:
- Size greater than 1 cm
- Tenderness
- Rapid growth
What are three ways to treat actinic keratosis lesions?
- Cryotherapy
- Imiquimod
- Fluorouracil
What lifestyle interventions help treat acne?
- Using water-based makeup for women
- Use a pH-neutral cleaner with warm water twice daily. Use gentle scrubbing to avoid aggravating acne.
What is the technical term for shaving rash?
Pseudofolliculitis barbae
What can decrease the risk of pseudofolliculitis barbae?
Pseudofolliculitis barbae results from hair curling into the skin, either the interfollicular space or within the follicle. By using a single-blade razor you cut the hair less deep which helps. Straight razors cut the hair not at an angle with also helps. Warm compresses prior to shaving also help. The man may need to discontinue shaving to allow the skin to heal.
Review the recommended treatment for localized and widespread actinic keratosis.
Localized lesions should be treated with topical cryotherapy and widespread lesions should be treated with 5-fluorouracil or imiquimod.
Review the characteristics of lichen planus.
The P’s:
- Papular
- Purple
- Pruritic
- Polygonal
Lichen planus in the mouth shows up as __________.
whitish lines on an erythematous base (Wickham striae)
You need to do __________ to diagnose lichen planus.
biopsy
Salicylic acid takes how long to work on verruca vulgaris?
2-3 weeks
True or false: erysipelas rarely has bullae.
False
Bullae, a well-demarcated erythema, and a peau d’orange appearance are all characteristic of erysipelas.
The two most common sites of erysipelas are __________.
face and leg
What facial finding suggests erysipelas rather than cellulitis?
Ear involvement (called Millan sign)
Erythema multiforme is most associated with _________ and ___________.
infections (HSV, Mycoplasma); malignancy
The _________ sign is when you put gentle pressure on the lesion and it sloughs off.
Nikolsky
True or false: SJS/TEN usually affects the hands and feet.
False
It usually spares the hands and feet.
TEN covers _________ skin than SJS.
more
When you see a patient with suspected SJS/TEN, use the ___________ tool to help predict their prognosis.
SCORETEN
Generalized pustules after starting a med could be what rash?
Acute exanthematous pustulosis
DRESS rarely involves the _________ surfaces.
mucosal
Scaling red skin that covers almost all the body is ___________.
scleroderma
Scleroderma is associated with what disease?
Cutaneous T-cell lymphoma
True or false: Pityriasis rosea is typically not pruritic.
False
It usually is pruritic.
Explain the pathophysiology of pityriasis rosea.
It’s not totally known what causes it, but it is thought to be a post-viral infection. It resolves in 8-12 weeks.
Sudden photosensitivity should make you think of what?
Lupus
Medication side effects (tetracyclines)
How long after starting a new medicine does DRESS usually start to develop?
Usually 2-4 weeks, but it can take up to 16 weeks
What genetic syndrome presents with an unusual amount of epidermoid cysts?
Gardner syndrome
Eczema (atopic dermatitis) generally affects the _________ surfaces.
flexural
Atopic dermatitis can cause accentuation of the lines under the eyes called __________ lines.
Dennie-Morgan lines
The difference between vesicles and bullae is _________.
size
Bullae are greater than 1 cm.
The difference between are erosion and an ulcer is ___________.
depth
Erosion goes into the epidermis. Ulcer goes into the subcutaneous tissue.
Rash appearing after a fever is classic for what diagnosis?
Roseola (aka Sixth Disease) from HHV6
When is chickenpox contagious?
2 days before and 5 days after the exanthem starts
HSP is now called?
Immunoglobulia A vasculitis (IGAV)
A patch is the larger (>1 cm) version of a _____________.
macule
True or false: crust means dead skin layers.
False
Dead skin layers is scale. Crust implies that some drainage has dried on the skin (e.g., impetigo).
The only steroid that comes in a 1 lb tub is _____________.
triamcinolone
The ________ layer of the skin appears shiny.
dermis
What is AGEP?
Acute Generalized Exanthematous Pustulosis
This is a diffuse erythema studded with nonfollicular sterile pustules. Usually, it appears after starting an antimicrobial agent (ampicillin, amoxicillin, metronidazole, and terbinafine).
How should you manage AGEP?
Stop the drug that caused it and admit
Staphylococcal scalded skin syndrome usually results after what type of Staph infection?
Perinasal impetigo
SSSS causes desquamation in what areas?
Intertriginous
Pityriasis rosea usually follows the __________ lines.
Langer
How much (in grams) ointment does it take to cover the body of an adult?
30 g
What infectious lab should be checked in patients with erythema nodosum?
ASO (provided they have a history of potential strep infection)
What is unique about graphite foreign bodies?
If not removed through excision (of surrounding tissues, too), then the graphite will likely lead to a tattoo.
Review the BSA of SJS, SJS/TEN, and TEN. .
SJS: < 10%
SJS/TEN: 10%-30%
TEN: > 30%
The circular telangiectasias seen on those with liver disease are also called _______________.
spider nevi
These are red, maculopapular rings that do not blanch.
A “targetoid lesion w/ central necrosis” is what rash?
E. multiforme
Erythema migrans is which infection?
Lyme disease
What is Brodie sign?
An area of blackness that can indicate necrotizing fasciitis
Gummas (erosive, ulcerating lesions) are associated with what disease?
Tertiary syphilis
__________ is thought to be the most mild form of SJS/TEN.
Erythema multiforme
Review the stages of pressure ulcer by structure exposed.
I: non-blanching erythema
II: dermis eroded but no fat visible
III: fat exposed but no muscle, tendon, or bone exposed
IV: muscle, tendon, or bone exposed
True or false: pemphigus vulgaris usually does not involve the mucous membranes.
False
Bullous pemphigoid usually does not involve the mucous membranes. Vulgaris usually does.
What is the pathophysiology of SJS/TEN?
Cytotoxic T-cell destruction of keratinocytes
Fixed drug eruptions tend to appear how?
Violaceous, pruritic macules that may have bullae
SJS after a cough?
MIRM: Mycoplasma-induced rash and mucositis
True or false: crusted shingles lesions are not contagious.
True
The progression goes erythematous papules/vesicles -> hemorrhagic papules/vesicles -> crusted lesions. The crusted lesions are the first non-contagious lesions.
What are the causes of erythema nodosum?
Infection:
- S pyogenes (most common)
- Mycoplasma
- Chlamydia
Autoimmune diseases:
- Sarcoid
- IBD
- SLE
Meds;
- Sula
- Peniicillin
- OCPs
- Phenytoin
Neoplasm:
- Lymphoma
Idiopathic
What are the lesions called in scabies?
Burrows
What is the mechanism of heat rash?
Sweat glands get blocked and rupture under pressure.
Both Parvovirus and HHV6 present with rash after a fever. How are they different?
Parvo starts on the face and then descends. HHV6 starts on the trunk.
How long is a typical course of clotrimazole for tinea?
4 weeks, and instruct the patient to continue it 1 week after resolution of the rash
Topical steroids and topical _______________ are the first-line treatments for atopic dermatitis.
calcineurin inhibitors (like topical tacrolimus)
How is infantile eczema different from childhood and adult eczema?
Infantile eczema is most often on the face and extensor surfaces, whereas childhood and adult eczema is on the flexural surfaces and wrists.
What is the most common type of skin cancer?
BCC
Describe the two ways the rash from disseminated N. gonorrhea presents.
Necrotic center with erythematous base
Purulent center with erythematous base
True or false: SSSS usually spares the mucous membranes.
True
What is papular acrodermatitis?
Also called Gianotti-Crosti syndrome, papular acrodermatitis is a post-viral rash that usually affects children younger than 5. It presents with flat-topped papules that are erythematous. It is associated with HBV, EBV.
Why should you not try to remove an inflamed epidermal cyst?
The wall is more friable when infected/inflamed, so full removal is unlikely.
Which sites are most common for fixed drug eruption?
Hands
Feet
Genitals
True or false: fixed drug eruptions are always painless.
False
They can be painless or present with burning or pruritus.
Exposure to which heavy metal increases risk for SCC?
Arsenic
“ArSKINic”
True or false: those with bullous pemphigoid should receive doxycycline.
True
Lupus pernio (violaceous rash on the cheeks and nose) are often seen in what rheumatologic disorder?
Sarcoidosis
What is the treatment for bullous pemphigoid?
Prednisone
