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Lauren Waskowicz

Primary Lesion Secondary Lesion
Flat: Macule (<5mm) versus patch (>4mm)
Raised: Papule (<5mm) versus plaque (>4mm)
Fluid Filled: Vesicle (<5mm) versus Bullae (>4mm) versus Pustule (pus-filled)
Nodule - firm, thicker, deeper, 1 and 2 cm in diameter. {br> Non Blanching: Petechial (<4mm) versus purpura (4-10mm)
Excoriations: “Excavations” dug into skin secondary to scratching
Lichenification: Roughing of the skin with accentuation of skin markings
Scale: Flakes of stratum corneum
Crust: Rough surface, dried serum, blood, bacteria, and cellular debris
Ulceration: Loss of epidermis and dermis
Erosion: Loss of the epidermis

Corticosteroids: General Principles

  • Main side effects ➔ skin atrophy
  • Face and intertriginous areas ➔ low potency steroids ONLY
  • High potency steroids should be limited to 3 weeks of use
  • Optimal absorption if applied after bathing (hydration promotes steroid penetration)
  • Ointments - most potent due to occlusive effect, good for thick, hyperkeratotic lesions and areas of smooth, NON-hairy skin. Avoid hairy and intertriginous areas (can cause skin maceration and folliculitis)
  • Creams - more cosmetically appearing and well tolerated. Less potent than ointments
  • Lotions - useful in hairy and intertriginous areas. Less potent than creams
Low Potency Medium Potency High Potency Very High Potency
Desonide 0.05% (cream, lotion, ointment) Triamcinolone (Kenalog) 0.025% (ointment, cream) Triamcinolone (Kenalog) 0.1% (ointment, cream) Betamethasone dipropionate 0.05% (ointment, cream, lotion)
Hydrocortisone acetate (OTC) Hydrocortisone valerate 0.2% (ointment, cream) Triamcinolone (Kenalog) 0.5% (ointment, cream) Clobetasol 0.05% (cream, ointment, lotion, gel, foam)

Common Rashes

Condition (link to pictures) Description/Symptoms Management
Morbilliform Drug Rash
(Link to Pictures)
- Erythematous macules ➔ confluent papules
- Trunk ➔ extremities, symmetric
- Most common precipitants = antibiotics (beta-lactam antibiotics, sulfa drugs), allopurinol, AEDs, NSAIDs
- Sx: Pruritus, low grade fever
- Discontinue offending agent
- Topical Corticosteroids, wet wraps
- Antihistamines
- If eosinophilia, kidney/liver dysfunction, mucous membrane lesions or painful/dusky lesions, consider alternative diagnosis (DRESS, AGEP, SJS/TEN)
Erythema Multiforme
(Link to Pictures)
- Abrupt onset of papular “target” lesions in symmetrical acrofacial sites, +/-mucosal involvement
- Usually precipitated by HSV
- Sx: Lesions can be painful, pruritic or swollen
- Systemic symptoms likely attributed to inciting infection (HSV, CMV, EBV, flu, COVID etc)
- Oral antihistamines and/or topical steroids for itch
- Treat precipitating infections (HSV tx does not alter course of single episode, can help prevent future inf)
- Stop offending medications
- If recurrent, derm referral for prolonged antiviral course
(Link to Pictures)
- Reactivation of VZV leading to blistering, painful rash in dermatomal distribution
- Rash can last 3-4 weeks
- Sx: Painful pustular lesions with systemic symptoms including fever, headache and lymphadenopathy
- Best treatment is prevention (shingles vaccine in adults >50)
- Valacyclovir 1000 mg TID if symptoms started w/in 72 hours and patient has new lesions) for 7 days OR acyclovir 800 mg 5x daily for 7 days
- Can be complicated by post-herpetic neuralgia, manage w/ early antiviral treatment, topical capsaicin, TCAs, gabapentin/pregabalin
Seborrheic Dermatitis
(Link to Pictures)
- Inflammatory response to malassezia yeasts
- Characterized by erythematous w/ yellowish and greasy scale of scalp, face, upper trunk, intertriginous areas
- Can be associated with HIV, parkinson's disease and use of neuroleptic medications
- Chronic, relapsing (mildest form = dandruff)
- Sx: Usually non-pruritic
- Mild symptoms + isolated to scalp (i.e. dandruff) ➔ antifungal shampoo (Rx: ketoconazole 2%, OTC: selenium sulfide 2.5%)
- Moderate/severe symptoms w/ scale, inflammation and pruritus of the scalp➔ antifungal shampoo + 2 week high potency topical corticosteroid followed by 2x weekly use of high potency topical steroids
*Tinea Pedis ('athlete's foot')
(Link to Pictures)

Tinea Corporis ('body ringworm')
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Tinea Capitis ('scalp ringworm')
(Link to Pictures)

Tinea Cruris ('jock itch')
(Link to Pictures)

Onychomycosis ('fungal nail infection')
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- Presentation depends on location
- Pedis: itchy erosions/scales between toes, hyperkeratosis/scale covering soles/sides of feet, vesiculobullous blisters of inner aspect of foot
- Corporis: solitary circular red patch with raised scaly leading edge, forms ring-shape with hypopigmentation
- Capitis: partial hair loss, +/- erythema, +/- pustular lesions
- Curis: erythematous bilateral but asymmetrical rash with raised border and central clearing
- Onychomycosis
- Perform KOH preparation if possible to confirm diagnosis
- Sx: Can be itchy and erythematous or asymptomatic
- Treat all sources of tinea to prevent re-infection.
- Nystatin IS NOT effective treatment
- Pedis/Corporis/Cruris: if localized infection ok for topical antifungals (clotrimazole 1% BID until clinical resolution 1-4 weeks)
- Capitis: Oral griseofulvin (500-1000 mg daily for 4-6 weeks) or oral terbinafine (250 mg once daily for 4 to 6 weeks)
- Onychomycosis: Oral terbinafine (250 mg once daily for 6 weeks (fingernail) or 12 weeks (toenail)), topical therapy (efinaconazole, amorolfine, ciclopirox)
(Link to Pictures)
- Inflammation of the skin around a finger or toenail
- Can be associated with felon (painful abscess at the base of the toe/nail) or herpetic whitlow (viral cutaneous infection caused by HSV)
- Usually due to staph/strep or pseudomonas
- Sx: Pain at the site of the infection, can develop systemic infection leading to fever/chills/myalgias
- If no abscess formation, can manage with soaking affected digit in warm water and antiseptics (chlorhexidine soaks TID) with mupirocin applied after soaking
- If abscess present ➔ I& D culture
- Antibiotics indicated if symptoms not improving after I&D or systemic symptoms (dicloxacillin 250-500 mg QID, cephalexin 500 mg QID) for 5 day duration
- If risk factors for MRSA ➔ Bactrim 1-2 DS tablets BID
- If oral flora present ➔ augmentin 875/125 mg BID
(Link to Pictures)
- Present as clusters of 2-3 mm umbilicated clear or hemorrhagic vesicles persisting for 5-10 days usually preceded by localized tingling/burning
- Type 1 most commonly associated with oral lesions, Type 2 w/ genital lesions
- Diagnose with viral culture of swab from vesicle or serologic testing (may be positive and not causing symptoms)
- Sx: Lesions are painful, can be associated with mild malaise and fever
- No cure, following initial infection immunity develops but does not prevent against further attacks
- Tx w/ topical therapy for mild infections
- For initial infection: Valacyclovir 500 mg BID 3-5 d, acyclovir 200 mg 5x/d for 5 days
- For recurrent infections: oral valacyclovir 500 mg BID for 3 days or 1 g daily for 5 days OR Acyclovir 800 mg BID for 5 days
- For suppressive therapy: oral valacyclovir 500 mg or 1 g daily

- Balanitis
(Link to Pictures)

(Link to Pictures)
- Balanitis: inflammatory versus infectious condition of the glans penis. Most commonly infectious cause (candida versus dermatophytosis)
- Sx: penile soreness, dysuria, itchiness, bleeding and erythema of the glans
- Candidal balanitis associated with white, curd-like exudate

- Intertrigo: erythematous/macerated plaques with peripheral scaling, often associated with superficial satellite papules or pustules
- Affects skin below breasts or under abdomen, armpits, groin and web spaces between fingers/toes
- Balanitis: attention to genital hygiene with retraction of foreskin and cleansing for prevention/therapy
- Clotrimazole cream BID for 7-14 days

- Intertrigo: Prevention with moisture-free skin, can use talcum powder to assist in intertriginous areas
- Topical antifungal agents (clotrimazole 1% cream BID for 4 weeks, 1% ointment BID for 2 weeks)
- Oral fluconazole or itraconazole for severe, generalized and/or refractory cases
Pityriasis versicolor
(Link to Pictures)

Pityriasis Rosacea
(Link to Pictures)
- Pityriasis versicolor: Superficial fungal skin infection caused by Malassezia
- Hypo/hyperpigmented or erythematous macules/patches or thin plaques most common on upper trunk, upper extremities
-Sx: usually asymptomatic

- Pityriasis rosacea: Self-limiting rash (6-10 weeks) characterized by large circular/oval “herald patch” found on chest/abdomen or back followed by small scaly oval red patches on back and chest (sometimes described in Christmas tree pattern)
- Sx: vary from mild to severe itching. ⅔ of patients have flu-like symptoms prior to rash onset
- Pityriasis versicolor: Topical antifungal treatment with ketoconazole 2% shampoo (Daily for 3 days), selenium sulfide 2.25% shampoo or terbinafine 1% cream

- Pityriasis rosacea: Self-limiting disease therefore treatment is symptom management
- Apply daily moisturizing creams, avoid drying soaps
- Can trial medium potency topical steroids and oral antihistamines
Atopic Dermatitis (Eczema)
(Link to Pictures)
- Lesions are pruritic, erythematous, +/- weeping/exudative, +/- blistering. Can become lichenified and scaly with fissuring over time.
- Most commonly occurs on neck, hands and flexural surfaces in adults
- Associated with atopic triad (asthma, eczema, and allergies)
- Avoid triggers (fabrics, chemicals, humidity, and dryness, foods)
- Daily skin hydration w/ emollients ointments > creams (take into consideration patient tolerability)
- Topical corticosteroids: Mild disease - hydrocortisone 2.5% BID until 3-5 d after skin clearance. Moderate disease - triamcinolone 0.1% or 0.025% Clobetasol cream for up to two weeks followed by mild steroids
- Skin and face folds treatment: Desonide 0.05% OR topical calcineurin inhibitors (tacrolimus 0.1% BID, discontinue when symptoms cleared)
(Link to Pictures)
- Clearly defined red and scaly plaques, symmetrically distributed
- Most common locations are scalp, elbows, knees
- Sx: Pruritus is common but mostly mild, treating can lead to hyper/hypopigmented plaques that fade over time
- Limited disease ➔topical corticosteroids and emollients - Scalp/external ear canal: potent corticosteroids - clobetasol propionate 0.05% BID until lesions clear
- Face/intertriginous: low-potency OTC hydrocortisone 1% or prescription-strength 2.5% BID until lesions clear
- Thick plaques on extensor surfaces: clobetasol propionate 0.05% BID until lesions clear
- Moderate to Severe ➔ Phototherapy + topical steroids/emollients, before systemic agents (e.g. MTX)
(Link to Pictures)
- Open and closed comedones, noninflammatory versus inflamed papules/pustule
- Severe cases involve nodules, pseudocysts with scarring
- Mild acne: daily topical retinoid (tretinoin) + benzoyl peroxide (if papulopustular lesions present)
- Moderate/severe: Isotretinoin (cumulative dose of 120-150 mg/kg)
- If isotretinoin is contraindicated, consider oral doxy (100 mg daily for 3-4 m) OR OCP OR spironolactone (25 to 50 mg/day in 1 to 2 divided doses, titrate based on response/tolerability)
Allergic Contact Dermatitis
(Link to Pictures)
- Type of eczema caused by allergic reaction to allergen (type IV hypersensitivity), usually 48-72 hrs after exposure
- Symptoms include erythematous, indurated pruritic plaques, +/- edema, +/- blistering, +/- scale
- Consider triggers such as nickel, fragrances/perfumes, work exposures, poison ivy
- Determine allergen, if not identified easily, can have comprehensive patch testing
- Acute/localized rash on hands/feet or nonflexural areas ➔ high potency topical corticosteroids BID until resolution (up to 4 weeks) then taper over 2 weeks
- Acute/localized rash on face/flexural areas ➔ medium/low potency topical steroids BID for 1-2 weeks then taper over 2 weeks OR topical tacrolimus 0.1% until resolution then taper
Stasis Dermatitis
(Link to Pictures)
- Caused by venous hypertension resulting from dysfunction of venous valves, obstruction to venous flow
- Sx: include edema, inflammatory skin changes, pruritus, tenderness, ulceration, varicosity and hyperpigmentation (hemosiderin deposition)
- Compression therapy with bandaging systems or stockings, elevation of legs, regular exercise other than standing
- Emollient (petroleum jelly) application for dryness/pruritus
- Acute disease w/ erythema, pruritus, vesiculation, and oozing ➔ consider high/mid-potency topical corticosteroids BID for 1-2 weeks
- Referral to vascular if persistent symptoms
(Link to Pictures)
- Chronic inflammatory condition affecting central face, usually appears between 30-60 yo
- Persistent facial redness, telangiectasia, thickening of skin and possible development of inflammatory papules/pustules.
- Pathophysiology multifactorial, includes genetic susceptibility, immune dysregulation, neurocutaneous triggers (sunlight, temperature, exercise, spicy foods, alcohol, stress, tobacco)
- Learn/avoid triggers (alcohol, tobacco),use gentle skin care products, and sun protection
- Consider pharmacological intervention with topical brimonidine, laser or intense pulsed light therapy
- If complicated by papular/pustular disease, consider topical metronidazole 0.75% gel for mild disease, and oral tetracycline/doxycycline for moderate to severe disease