Special Pops Lecture 8: General Dermatology

Macules

flat, reddened lesions that can be differentiated by color

Papules

solid, elevated lesions that are small (<1 cm in diameter)

Nodules

solid, round, ellipsodial lesions that can extend into the dermis

How can we differentiate a papule from a nodule?

depth of skin - nodules can get into the dermis

Blister

vesicles and bullae

Vesicle

lesion that contains clear fluids

Bullae

vesicles larger than 0.5 cm in diameter

Plaque

Large, slightly elevated lesion with flat surface, often topped by scale

Wheal

rounded or flat topped elevation that is red and itchy

What are the risk factors for developing skin reactions?

Prior drug reactions

On multiple drugs

Repeated use of the same drug

Current viral illness

Higher levels of drug in serum

Topical ROA

Genetics

Comorbidities

What are the two types of drug induced skin reactions?

Allergic

Irritant

Allergic skin reaction

delayed systemic reaction that has an immune response from the host

Irritant skin reaction

fast onset and localized skin reaction

What systemic drugs typically cause ADRs?

Allopurinol

Sulfonamides

Anticonvulsants

Dapsone

Penicillins

Maculopapular skin reaction

afebrile patient with erythematous macules and papules that may itch across the whole body

How long does it take for a maculopapular rash to develop?

7-10 days

What is the most commonly encountered skin reaction?

Maculopapular skin reactions

How long does it take for maculopapular rashes to resolve?

7-14 days after D/C

What drugs commonly cause a maculopapular skin reaction?

Penicillins

Cephalosporins

Sulfonamides

Angioedema

edema of the SQ or submucosal tissues that are typically in the face but can spread to the GI tract

What drugs commonly cause angioedema?

ACEi/ARBs

Penicillin

NSAIDs

MAbs

Contrast media

Urticaria

IgE mediated allergic reaction that appears as itchy wheals with central blanching

- may be a precursor to anaphylaxis

How long does urticaria last?

Starts within minutes and resolves within 24 hours

What drugs commonly cause urticaria?

Penicillins

Aspirin

Sulfonamide

Contrast media

Opiates

Latex

MAbs

Drug Reaction with Eosinophilis and Systemic Symptoms (DRESS)

exanthematous eruption AND eosinophilia, fever, lymphadenopathy, and multiorgan involvement

How long does DRESS last?

develops in 1-4 weeks and can take weeks/months to resolve

What drugs commonly cause DRESS?

Allopurinol

Sulfonamides

Dapsone

Serum Sickness-Like Reaction

urticarial eruptions PLUS fever, rash, and arthralgias with NO IMMUNE INVOLVEMENT

What is the onset time of serum-sickness like reactions?

1-3 weeks

What drugs commonly cause serum-sickness like reactions?

Antibiotics

Fixed drug eruptions

pruritis, red, raised lesion that may blister and evolve into a plaque at the same location where the drug is given

How long does a fixed drug eruption last?

appears in minutes to days and resolves within days BUT leaves behind hyperpigmented skin for months

What drugs typically cause fixed drug eruptions?

Tetracyclines

Barbiturates

Sulfonamides

Codeine

Acetaminophen

NSAIDs

Metronidazole

Stevens-Johnson's Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)

allergic blistering eruption (SJS) that can eventually slough off (TEN) and be life threatening

What is the difference between SJS and TEN?

Body surface area: TEN > SJS

What are the complications of SJS/TEN?

Fluid loss

Kidney failure

Corneal ulcerations

Infections

Erosive vulvovaginitis

What drugs commonly cause SJS/TEN?

Sulfonamides

Penicillins

NSAIDs

Allopurinol

How long does SJS/TEN take to arise?

7-14 days

Acneiform reactions

pustular eruptions that appear in 1-3 weeks

What drugs commonly cause acneiform drug reactions?

Corticosteroids

Androgenic hormones

Isoniazid

Lithium

Acute Generalized Exanthematous Pustulosis (AGEP)

acute pustular eruption PLUS fever and diffuse erythema that can appear within days

What drugs commonly cause AGEP?

Beta lactams

Macrolides

Calcium channel blockers

Phototoxic Photosensitivity Rection

rapid onset of a burning sensation that is similar to a severe sunburn - ONLY on sun-exposed skin

What drugs commonly cause phototoxic reactions?

Amiodarone

Tetracyclines

Sulfonamides

Photoallergic photosensitivity reaction

rash that transforms UVA light into allergens and includes non-sun exposed skin 24-72 hours after exposure

What drugs commonly cause photoallergic reactions?

Sulfonamides

Sulfonylureas

Thiazides

NSAIDs

Chloroquine

Carbamazepine

What is the management for skin ADRs?

Stopping the offending agent

Supportive/symptomatic treatment

Cystic acne

a cyst of connective tissue that forms due to infection of sebaceous glands that requires aggressive treatment

What are the types of cystic acne?

Acne conglobata

Ance fulminans

Pyoderma faciale

Acne conglobata

a chronic, highly inflammatory form of cystic acne in which involved areas contain a mixture of double comedones, two blackheads that communicate under the skin, papules, pustules, communicating cysts, abscesses, and draining sinus tracts

Acne Fulminans

rare, ulcerative form of necrotic acne

Pyoderma faciale

cystic acne that remains confined to the face fo adult women

What are the treatment options for cystic acne?

Oral and topical antibiotics

Kenalog injections into cysts

Isotretinoin

Psoriasis

A noncontagious inflammatory skin disease characterized by recurring reddish patches covered with silvery scales caused by uncontrolled T cell replication

What are the topical treatment options for psoriasis?

Calcipotriol

Calcitriol

Calcipotriene

Steroids

Anthralin

Tazarotene

What are the systemic treatment options for psoriasis?

Acitretin

Cyclosporine

Methotrexate

Alefacept

Efalizumab

Eczema

noninfectious, inflammatory skin disease characterized by redness, blisters, scabs, and itching

What are the treatment options for eczema?

Hydration

Topical steroids

Phototherapy

Antihistamines

Pimecrolimus cream

Tacrolimus cream

MOA of topical steroids

anti-inflammatory, anti-proliferative, immunosuppressive