Dermatology Flashcards
Where do the majority of infants have atopic dermatitis?
Infants will usually have it present over the extensor surfaces. Once in childhood it is commonly seen on flexor surfaces.
What do the lesions of dyshidrosis look like?
Patients present with pruritic vesicles over the fingers.
What is the treatment of choice for lichen simplex chronicus?
Stop scratching and apply topical steroids.
Lichen planus is associated with what infection?
Hepatitis C, however, routine screening is not recommended.
What are the four Ps of lichen planus?
- Pruritic
- Purple
- Polygonal
- Plaque like
What is the classic presentation of pityriasis rosea?
Patients will present with a herald patch (large single round lesion). Then, the patient will have lesions appearing over the back in a christmas tree pattern.
Psoriasis tends to improve during what season?
Improves during the summer and worsens in the winter.
Differentiate erythema multiforme minor from major.
The difference here is mucosal involvement.
Minor = no mucosa
Major = mucosa
What is the most common etiology responsible for erythema multiforme?
Herpes Simplex Virus
How does body surface area play apart in SJS vs TEN?
They are the same disease characterized by how much body surface is involved.
SJS = 30%
SJS/TEN overlap = 10%-30%
What is nikolski sign?
Seen in SJS or TEN. Gentle pressure to the patients skin will cause sloughing.
Patients with bullous pemphigoid are usually what age?
Patients are usually >60 years of age.
Clinical activity of bullous pemphigoid correlate with what lab?
It will correlate with BP180 levels.
What is the last step in management for acne vulgaris?
Oral isotretinoin.
What is the most common cause of androgen production in women?
PCOS
What type of birth control should be avoided in patients with acne?
Progestin only birth control will worsen acne.
Describe rhinophyma?
Seen in patients with phymatous rosacea. Most commonly seen in males and will present with tissue hypertrophy of the nose.
A patient is described to have a warty, hyperpigmented lesion, that appears stuck on. What is the most likely diagnosis?
This is classic for seborrheic keratosis.
What is first line treatment for scabies?
Permethrin 5% cream. Permethrin 1% is used for lice.
What is the major risk factor for developing basal cell carcinoma?
UV light is the major risk factor. Its also the major risk factor in squamous cell carcinoma and melanoma.
When evaluating the possibility of melanoma, what rule should you use?
Remember the ABCDE rule! Assymetry Border Color Diameter Evolution
What is the treatment of choice for onychomycosis of the toes?
Patients are treated with 12 weeks of terbinafine. If the hands are involved, treatment is for 6 weeks.
What is the etiology in acute and chronic paronychia?
Acute = staphylococcus areus and streptococcus pyogenes. Chronic = eczematous process/candida
Differentiate cellulitis vs erysipelas.
Cellulitis involves the deep dermis and subcutaneous fat and is caused by strep and staph. Erysipelas involves the upper dermis and caused by streptococcus.