10. Dermatology Flashcards
Enlarging nodule at site of burn injury with persistent pain and drainage is most likely what?
Squamous cell carcinoma - may arise within chronically wounded, scarred, or inflamed skin
Dentist with 4 week hx of scaly, pruritic rash on hands. Rash is d/t what?
Irritant contact dermatitis - possibly d/t frequent hand washing.
Nonimmunologically mediated but can resemble allergic contact dermatitis
Allergic contact dermatitis due to jewelry is most likely due to what metal?
Nickel - corrosion of metal alloys by electrolytes in sweat releases soluble metal ions that trigger a type IV sensitivity reaction.
Tx - low potency topical corticosteroid
What percent of patients with acute urticaria is idiopathic? What are other common causes?
50% idiopathic
Other causes: infections, NSAIDs, IgE mediated or direct mast cell activation.
Pruritic rash with a scaley, erythematous border and central clearing in a patient with diabetes. Dx?
Tinea - trichophyton rubrum is the most freqeunt cause.
Dx - KOH prep (segmented hyphae and arthrospores)
Differentiate rosacea rash from SLE rash
Both cause facial rash in similar distribution area
Rosacea - telangiectasias seen. Precipitated by hot drinks, ETOH, heat, emotion, and other causes of rapid body temp change. Includes nasolabial folds
SLE - darker, spares nasolabial folds, no affected by ETOH, accompanied by other manifestations of lupus
Firm, flesh-colored, dome-shaped, umbilicated papules characterizes what condition? Who is more at risk for this?
Molluscum contagiosum
Patients with impaired cellular immunity (eg HIV) are at risk for more severe, widespread disease
What is a benign neonatal rash characterized by blanching erythematous papules and/or pustules that resolves spontaneously within 2 weeks after birth?
Erythema toxicum neonatorum
What is initial management for inflammatory acne? In pts with mod to severe inflam acne, what should be given?
Initial: Topical retinoids, benzoyl peroxide
Topical abx first, then Oral abx given for severe inflam acne
What infection can be superimposedon atopic dermatitis that causes painful vesicles with an erythematous base that evolves into punched-out erosinos with hemorrhagic crusting?
Eczema herpeticum - HSV infx on top of atopic dermatitis
What is the best way to manage bullous pemphigoid (linear IgG and C3 deposits in the dermal-epidermal junction)
Confirm dx with skin bx and treat with Topical clobetasol (high-potency glucocorticoid).
Note; has inc incidence in those with malignancy or neuro disorders (eg Parkinsons, MS).
Differentiate a lipoma from an epidermal inclusion cyst
Lipoma: painless subq mass with normal epidermis. Soft to rubbery and irregular and do not typically regress and recur.
Epidermal inclusion cyst: benign nodule with squamous epithelium that produces keratin. Dome-shaped, firm, freely movable, with small central punctum. Can remain stable or gradually inc in size but may produce a cheesy white discharge
