Dermatology For Boards (And Real Life)

Rita Khodosh, MD, PhD Department of Dermatology UC San Francisco Question

A 32-year-old farmer comes to your office because of an upper respiratory infection. While he is there he points out a lesion on his forearm that he first noted approximately 1 year ago. It is a 1-cm asymmetric nodule with an irregular border and variations in color from black to blue. The patient says that it itches and has been enlarging for the past 2 months. He says he is so busy that he is not sure when he can return to have it taken care of.

Suspicious Pigmented Lesion Question In such cases the best approach would be to

. perform a punch biopsy and have the patient return if the biopsy indicates pathology . perform a shave biopsy, with a recheck in 2 months for signs of recurrence . use electrocautery to destroy the lesion and the surrounding tissue . perform an elliptical excision as soon as possible . freeze the site with liquid nitrogen Melanoma

• Destruction (cryotherapy, electrodessication, currettage) is NEVER appropriate • Best way to biopsy a suspicious pigmented lesion is an EXCISIONAL BIOPSY (elliptical, punch, or saucerization) • To properly stage and plan treatment of a Melanoma one needs to know it’s greatest DEPTH

Melanoma Margins Melanoma Sentinel Lymph Node Biopsy

Sentinel Lymph Node Biopsy is offered for melanomas : • >1mm Breslow Depth • <1mm with ulceration, increased mitotic rate and certain adverse features Melanoma Biopsy Real Life Melanoma Biopsy Real Life • Sometimes, a partial biopsy is okay… • Don’t let the perfect be the enemy of the good enough • If you are not comfortable performing a biopsy, make sure the patient is seen without delay by a provider who is (Dermatology, ENT, Plastics, General surgery, etc) Question

A 72-year-old white farmer presents to your office with an enlarging raised lesion on the dorsum of his hand. It appears to be arising from an area of actinic keratosis.

Erythematous scaly papule on dorsal hand Question

Due to its location you suspect which one of the following? A) Basal cell carcinoma B) Keratoacanthoma C) Malignant melanoma D) Psoriatic plaque E) Squamous cell carcinoma

Cutaneous Squamous Cell Carcinoma

• Most associated with chronic sun exposure (cumulative effect) • Scalp, face, dorsal hands, neck • Other risk factors for development of SCC: - burn - chronic ulcer - radiation - HPV (anogenital) - immunosuppression Cutaneous Squamous Cell Carcinoma

Higher risk for recurrence and metastasis include: • Size >2cm • Depth (>4cm) • Perineural invasion (Painful lesion) • Immunosuppression • Location on the ear, lip, anogenital

Keratoacanthoma

• A type of SCC? • Rapid growth • Nodule with keratinous core • Can involute on its own • Usually treated • Excision is best

Question

You note a skin lesion on the nose of a 70- year-old male painter during a visit for a routine upper respiratory infection. He tells you that the lesion "sometimes bleeds a little." It is a raised, smooth, pale, pearly, shiny papule with prominent telangiectasia evident across its surface.

Shiny papule with prominent telangiectasia Question

This lesion is most likely

A) a spider angioma B) a basal cell carcinoma C) an atypical melanoma D) actinic keratosis E) sebaceous hyperplasia

Basal Cell Carcinoma

• Most common type of skin cancer • Sun-exposed areas (face, neck) • Fair skin, sunburn history • Rarely metastasize, some can be locally invasive and aggressive • Diagnosed with shave or punch biopsy (punch if you are worried about more infiltrative BCC) BCC Treatment

• Face (especially mid face)—Mohs procedure • Excision • Electrodessication and Curettage (not on face or neck, not for infiltrative BCC) • Imiquimod or 5FU (Superficial BCC) • Radiation if cannot tolerate surgery (usually elderly patients) • Vismodegib--hedgehog pathway inhibitor (metastatic or inoperable BCC) Question

Which one of the following statements is consistent with current U.S. Preventive Services Task Force recommendations for skin cancer screening for the adult general population with no history of premalignant or malignant lesions?

Skin Cancer Screening

A) Whole-body examination should be conducted by a primary care provider every 3 years B) Whole-body patient self-examination should be performed every 6 months C) Benefits from screening have been established only for high-risk patients D) The evidence is currently insufficient to determine whether early detection reduces mortality and morbidity from skin cancer E) The harms of detection and early treatment outweigh the benefits

Skin Cancer Screening

• The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of visual skin examination by a clinician to screen for skin cancer in adults I screen • patients with history of skin cancer • patients with fair skin over 50 (especially men) who have evidence of significant sun damage or patients with other risk factors for NMSC • patient with increased melanoma risk

UV radiation causes melanoma What about indoor tanning? Question

A 55 year old white female presents with redness at the scar from a lumpectomy performed for stage I cancer of her right breast 4 months ago. The patient has completed radiation treatments to the breast. She is afebrile and there is no axillary adenopathy. There is no wound drainage, crepitance, or bullous lesions.

Question

Which one of the following organisms would be the most likely cause of cellulitis in this patient?

A) Non group A Streptococcus B) Pneumococcus (Strep pneumoniae) C) Clostridium perfringens D) Escherichia coli E) Pasteurella multocida

Causes of Cellulitis

• Beta-hemolytic Streptococci (most often Group A) • Staph Aureus • Non-purulent cellulitis—cover for Strep and MSSA (Cephalexin) • Purulent cellulitis—cover for MRSA (Bactrim DS, Doxycycline, Clindamycin) and culture • Abscess—INCISION AND DRAINAGE Unless complicated (cellulitis, immunocompromised, fever, etc) Other Staph and Strep infections

Impetigo • S. aureus more common • Beta-hemolytic Strep less • Localized cases can be treated with mupriocin • More generalized with oral antibiotics (Cephalexin or Dicloxacillin) for 7 days • Culture (if MRSA, tx with doxycycline, clinda or trimethoprim-sulfamethoxazole)

Other Staph Infections Acute Paronychia • No abscess—warm soaks and topical mupirocin • Abscess—drainage, soaks and mupirocin • Culture • Oral anti-staph antibiotics for 7 days for more severe cases

Chronic Paronychia

- Eczematous process - Minimize irritation and damage - Treat with topical steroids first - Candidal infection is secondary

Not to be confused with Herpetic Whitlow

• Grouped vesicles on an erythematous base • HSV 1 or 2 infection of finger from oral inoculation (most often in children, healthcare workers) • Painful, can have fever and regional lymphadenopathy • DFA or viral culture to confirm • Do not need to treat, self-limited Herpes Zoster Reactivation of latent VZV Treatment of Herpes Zoster

• Antiviral therapy with acyclovir, valacyclovir, famciclovir • Best when given within first 72 hours • Treat after 72 hrs if still getting new lesions, immunosuppressed, pregnant • Treat pain! • Warn about contact with pregnant women, unvaccinated babies, immunocompromised • Treat with antivirals AND call ophthalmology if Herpes Zoster Ophthalmicus Question

Imiquimod (Aldara) is approved by the FDA for treatment of which one of the following conditions? A) External anogenital warts B) Plantar warts C) Flat warts D) Periungual warts E) Molluscum contagiosum

External anogenital warts Imiquimod

• A toll-like receptor-7 agonist • Enhances both the innate and acquired immune response • FDA approved for treatment of external anogenital warts • Sometimes used for other types of warts (flat warts > verruca vulgaris), but it does not work as well • Sometimes used for Molluscum, but cantharidin and cryotherapy work better

Question

• An otherwise healthy 37-year-old male presents to your office with a 2-week history of redness and slight irritation in his groin. On examination a tender erythematous plaque with mild scaling is seen in his right crural fold. The area fluoresces coral-red under a Wood’s light.

Question

Which one of the following would be the most appropriate treatment at this time? A) Amoxicillin B) Erythromycin C) Ketoconazole D) Nystatin (Mycostatin) E) Triamcinolone (Kenalog)

Erythrasma Erythrasma

• Erythrasma is caused by C. minutissimum, a component of the normal skin flora • Overgrowth in stratum corneum occurs under conditions of occlusion and moisture • Topical erythromycin and clindamycin are first line • Oral clarithromycin or erythromycin for extensive disease • Topical imidazole antifungals (econazole) also work

Other Groin Rashes

Candida • Moist • beefy red • Satellite pustules • Keep area dry • Nystatin • Imidazole antifungals

Other Groin Rashes Tinea Cruris • Scaly plaque • Serpiginous scaly border - Topical Imidazoles or Allylamines (Terbinafine) - Oral Terbinafine for extensive tinea corporis

Question

A 69-year-old female sees you for an annual examination. She asks you to look at her toes, and you note a fungal infection in five toenails. She says the condition is painful and limits her ability to complete her morning walks. She asks for treatment that will allow her to resume her daily walks as soon as possible. Her only other medical problem is allergic rhinitis which is well controlled.

Onychomycosis Question

Which one of the following would be the most appropriate treatment for this patient? A) Oral griseofulvin ultramicrosize (Gris-PEG) daily for 12 weeks B) Oral terbinafine (Lamisil) daily for 12 weeks C) Topical terbinafine (Lamisil AT) daily for 12 weeks D) Topical ciclopirox (Penlac Nail Lacquer) daily for 12 weeks E) Toe nail removal

Onychomycosis

• Dermatophyte infection most common—tinea unguium • Candida and non-dermatophyte mold (Fusariam, Aspergillus, others) • Diagnosis: PAS—most sensitive, Culture--only about 50% sensitivity • Treatment not necessary if asymptomatic • Treat if recurrent cellulitis (diabetics), pain, immunosuppression, patient preference

Onychomycosis Treatment

• Not that effective • Treat for presumed dermatophyte infection while waiting for culture results • Oral Terbinafine 250mg daily for 12 weeks • Cure rate about 70%, but only 35% at 5 years • Itraconazole, same cure rate, more side effects • Topicals: Efinaconazole, Tavaborole, Ciclopirox (cure rates 25%, 18%, 7% respectively) Erythema Migrans 7-14 days after tick bite Lyme Disease

- Caused by Borrelia spirochete transmitted by bite of Ixodes deer tick - In early Lyme disease serologic testing is likely to be negative - Diagnosis should be made based on the clinical picture (EM lesion or lesions, non- specific viral symptoms, and history of living in or travel to an endemic area Treatment: - Doxycycline 100mg BID for 10-21 days or - Amoxicillin 500mg po BID for 14-21 days

Secondary Syphilis

Treponemal test (FTA-ABS) to screen and non-treponemal test (RPR) to confirm Treat with Penicillin G Scabies Scabies

• Erythematous papules, pustules, burrows • Likes hands, skin folds, groin, less on head • Very itchy • SCRAPE IT • Treat all family members • Permethrin cream x 2 • Ivermectin PO if crusted

Question

Which one of the following would be considered first-line therapy for mild to moderately severe psoriasis confined to the elbows and knees? A) Phototherapy using ultraviolet B light B) Methotrexate C) Etretinate (Tegison) D) Betamethasone dipropionate (Diprolene)

Psoriasis

Well-defined, erythematous plaques with silvery scale

Psoriasis Treatment

• LOCALIZED DISEASE—TOPICAL TREATMENT • Topical steroids (Clobetasol) • Topical retinoids (Tazorac) • Topical Vitamin D derivatives (Calcipotriene) • Tar • Combinations of topical treatments are more effective • Intralesional Steroids • NB UVB (more generalized disease) Psoriasis Psoriasis Treatment

• Generalized disease, arthritis—systemic treatment • Methotrexate • Acitretin, Cyclosporin (less often) • Apremilast—Otezla (oral PDE4 inhibitor) • Biologics: - TNF alpha inhibitors (Adalimumab-Humira) - IL 12/23 inhibitor (Ustekinumab-Stelara) - IL 17 inhibitors (Secukinumab-Cosentyx)

Psoriasis Real Life • Psoriasis patients have systemic inflammation • Co-morbidities: obesity, diabetes, cardiovascular disease • More severe psoriasis--higher risk of co- morbidities • Counsel patients about diet, exercise, treat co- morbidities • TNF alpha inhibitors may be more effective at reducing cardiovascular risk than Methotrexate Question While vacationing, a 27-year-old white male was exposed to poison ivy. Between 48 and 72 hours after exposure he developed a pruritic, erythematous, papulovesicular eruption on his arms and neck. He was given oral methylprednisolone (Medrol Dosepak), starting with 24 mg/day and tapered by 4 mg/day over 6 days. His condition began to improve, but on day 6 he noted a dramatic exacerbation of the eruption with intense pruritus, erythema, and vesiculation, involving extensive areas of his arms, neck, and face.

Allergic Contact Dermatitis Poison Oak Question

The most appropriate management at this time would be to A) prescribe a superpotent topical corticosteroid B) repeat the oral methylprednisolone treatment C) begin diphenhydramine (Benadryl), 4 times a day D) begin high-dose oral prednisone and taper over 2 weeks E) discontinue all medications and recommend cool compresses

Allergic Contact Dermatitis to Urushiol in Poison Oak (Ivy or Sumac) • Type IV hypersensitivity reaction • Localized eruptions can be treated with potent or superpotent topical steroids (clobetasol) • Oral prednisone is given for more extensive eruptions • Needs to be started at a high dose (60mg) and tapered slowly over 2-3 weeks • If tapered too quickly, patient will flare • Antibiotics if secondarily infected (Staph)

Eczema/Atopic dermatitis Eczema/Atopic dermatitis

• Itchy erythematous scaly papules and plaques • Patients with atopy (allergic rhinitis, asthma, FH) • Problem with epidermal barrier and immune dysregulation • Treatment MUST address both!

Eczema Treatment

• Emollients, gentle skin care, avoidance of irritants and topical allergens • Topical steroids 1st line • Topical calcineurin inhibitors • Do not use antibiotics unless impetiginized • Treat pruritus (sedating antihistamines) • Phototherapy • Immunosuppressive agents for severe cases • No evidence that dietary restriction is useful

Question

Patients presenting with erythema multiforme often have a prodromal history of A) egg allergy B) recent immunization C) herpes simplex infection D) thennal trauma E) streptococcal infection

Erythema Multiforme Erythema Multiforme

• Target lesions (three zones: dark dusky center, pale ring of edema, erythematous halo) • Can be atypical, with just 2 or 1 zone • Hypersensitivity reaction to • Infections (most commonly HSV, Mycoplasma pneumoniae, many others) • Drugs are a less common cause (NSAIDs, Antibiotics, Anticonvulsants, others) • If recurrent, treat with suppressive HSV therapy Erythema Multiforme due to Mycoplasma pneumoniae infection

Check mycoplasma serologies (IgM, IgG) Treat infection with azythromycin or doxycycline Stevens Johnson Syndrome (SJS) & Toxic Epidermal Necrolysis (TEN) Stevens Johnson Syndrome (SJS) & Toxic Epidermal Necrolysis (TEN) • Severe mucocutaneous reaction usually caused by a medication • Starts with fever, flu-like symptoms, mucosal pain • Mortality up to 30%, higher in adults • Allopurinol • Aromatic anticonvulsants (phenobarbetal) • Antibacterial sulfonamides (Bactrim) • Lamotrigine • STOP the MEDICATION and call a derm and a burn center Question A 20-year-old female college tennis player presents with painful anterior lower leg lesions. You note several 2- to 3- cm deep, tender, warm lesions over both shins. The patient denies specific trauma or increased exercise. The most significant etiology to be considered in this case is A) papular urticaria B) early rheumatoid arthritis C) shin splints D) superficial thrombophlebitis E) oral contraceptive use

Erythema Nodosum Erythema Nodosum

• Panniculitis • Delayed-type hypersensitivity reaction to: • Infection (Streptococcal most common) • Drugs (OCPs, antibiotics) • IBD • Pregnancy

Erythema Nodosum Treatment

• Self-resolving, but takes several weeks • Treat underlying condition • Supportive treatment • Leg elevation • Rest • NSAIDs • If severe, can consider short course of low- dose prednisone (20mg 7-10 days)

Acne

Acne • Assess severity • Mild to moderate—topical therapy (retinoids, Benzoyl Peroxide, clindamycin) • Moderate—course of antibiotics (Doxy, Keflex, Bactrim), limit to 6 months. Hormonal treatments for women (OCP, spironolactone) • Severe (nodulocustic/scarring)—Isotretinoin (teratogen, otherwise quite safe) Urticaria Pruritic lesions last < 24hours Urticaria

• Acute urticaria < 6 weeks • Chronic urticaria > 6 week • Triggers - Foods—acute - Medications and Infections - Over 50% of chronic urticaria is idiopathic • Treat with anti-histamines (non-sedating up to 4 times the daily dose) • Do not use prednisone, especially for chronic

Question A 30-year-old white male presents with a polymorphous skin rash consisting of grouped vesicles,urticarial wheals, and papular lesions distributed symmetrically over the elbows, knees, and buttocks. A skin biopsy shows IgA deposition and a diagnosis of dermatitis herpetiformis is made. The mainstay of therapy is A) dapsone B) prednisone C) cephalosporins D) methotrexate E) tetracycline

Dermatitis Herpetiformis Dermatitis Herpetiformis

• Associated with gluten sensitivity—celiac disease • ELISA for IgA tissue transglutaminase antibodies and IgA epidermal transglutaminase antibodies Treatment • Strict gluten-free diet works slowly • Dapsone works quickly, can later be discontinued

Question

A 25-year-old female has an annular rash on the dorsal surface of both hands. The rash does not respond to initial treatment with an antifungal medication, and a biopsy reveals granuloma annulare. Which one of the following would be the most appropriate advice for this patient?

A) Allow the rash to resolve without further treatment B) Cover the rash because it is contagious C) Treat the rash with systemic corticosteroids D) Treat the rash with a stronger antifungal medication

Granuloma Annulare Granuloma Annulare

• Non-scaly erythematous annular papules and plaques on dorsal hands, elbows, feet, knees • A benign, reactive condition, can self resolve • Treatments included superpotent topical steroids, intralesional steroids, phototherapy • Systemic treatment, such as plaquenil or dapsone, is offered for disseminated, symptomatic GA that does not respond to phototherapy Question

A 50-year-old female presents with a 3-week history of a moderately pruritic rash, characterized by flat- topped violaceous papules 3–4 mm in size. The lesions are located primarily on the volar wrists and forearms, lower legs, and dorsa of both feet. Ten days after the rash first appeared she went to the emergency department and was treated for “possible scabies,” but the treatment has made little or no difference.

Question

Which one of the following treatments is indicated at this time? A) Clobetasol (Cormax, Temovate) 0.05% ointment B) Permethrin 5% cream C) Tacrolimus (Protopic) 0.1% ointment D) Triamcinolone 0.1% cream

Lichen Planus

• 5 P’s: pruritic, purple, planar (flat-topped), polygonal papules • Wickham striae • wrists/ankles classic • Oral/genital involvement • Can be erosive • Etiology unknown • ?Associated with Hep C?

Lichen Planus

• Benign condition, erosive disease (oral/genital) requires more aggressive treatment • Potent or superpotent topicals steroids (fluocinonide, clobetasol) are first line tx • Topical calcineurin inhibitors can be used (tacrolimus) • Other tx: phototherapy, oral prednisone course, oral retinoids (acitretin), MTX, plaquenil Alopecia Scarring vs Non-Scarring

Non-scarring Alopecia Areata Scarring Discoid lupus Alopecia

Non-scarring Scarring - Androgenetic - Discoid lupus (pattern) - Lichen planopilaris - Alopecia areata - Folliculitis decalvans - Syphilis - Sarcoidosis - Trichotillomania - Traction-late

Question

A 5-year-old African-American child has been experiencing scalp pruritus for several months, along with hair loss in a “moth- eaten” pattern. Small block dots can be seen within the larger alopecic patches. A potassium hydroxide (KOH) reparation shows occasional branching hyphae and multiple spores.

Tinea Capitis Tinea Capitis

• Moth-eaten pattern alopecia in a child • Erythema • Scale • Black Dots (hairs broken off at skin surface) • Boggy induration (Kerion)

Question

Which one of the following is the preferred treatment?

A) Topical ketoconazole (Nizoral) B) Topical minoxidil (Rogaine) C) Oral griseofulvin (Fulvicin) D) Oral hydroxyzine (Atarax) E) Psoralen-ultraviolet A (PUVA) therapy

Tinea Capitis Diagnosis • KOH preparation (scrape area of scale) hyphae and spores

• Culture (scrape area of scale and pluck hairs with roots) • Culture will differentiate between Microsporum Species and Trichophyton species (M. Canis and T. Tonsurans) Tinea Capitis Treatment • Long Course (4-6 weeks or more) • Griseofulvin 20-25 mg/kg divided bid x 6-12 weeks (give with ice cream of other fatty food) • Works best against Microsporum Species • Lamisil (Terbinafine) 5mg/kg/d x 4 wks • Works best against Trichophyton Species • Itraconazole has a worse side effect profile, do not use first line for skin/nail infections

Kerion Kerion

• Inflammatory reaction to tinea infection • Can lead to scarring • Not a bacterial infection—does not require antiobiotics • We often add low-dose prednisone to treat inflammation and to minimize scarring

Question • A 62-year-old female presents with painful lesions at both corners of her mouth characterized by redness, scaling, and deep cracks. The cracks sometimes bleed when she opens her mouth. She has treated them with bacitracin/neomycin/polymyxin B ointment (Neosporin) but says it has not helped. • Which one of the following would be most appropriate at this point? • A) A biopsy of the lesions • B) An anticandidal medication • C) Bacitracin • D) Vitamin B12

Angular Cheilitis Angular Cheilitis

• More common in elderly people • Ill-fitting dentures • Dry mouth • Poor oral hygiene • Complicated by candidal or staph infection • Barrier creams (zinc or vaseline) • Treat infection • Minimize exacerbating factors • Can check for B12 or iron deficiency