Back to the Basics LMCC Preparation Dermatology Jim Walker Assoc. Clinical Prof. Medicine Dermatology
Websites Ottawa U Dermatology Block Slides http://www.med.uottawa.ca/curriculum/dermato.htm UBC Dermatology Undergraduate Problem Based Learning Modules http://www.derm.ubc.ca/teaching Good Quiz site & Resource – Johns Hopkins Univ. http://dermatlas.med.jhmi.edu/derm/ eMedicine Textbook http://www.emedicine.com/derm/index.shtml Medline http://www.ncbi.nlm.nih.gov/pubmed University of Iowa Dept of Dermatology http://tray.dermatololgy/uiowa.edu/home.html Dermatology Online Atlas http://dermis.multimedica.de/ * Please do not use images without attribution or permission!
Morphology Living gross pathology of skin, hair nails and visible mucosae Review basic lesions, the nouns (papules, ulcers etc.) Add the adjectives (size, shape, colour, texture, etc.) Consider distribution, symmetry and pattern Visual literacy: simple descriptions→complex interpretations (you see, but do you observe?) Excellent lighting Position patient Look all over (skin, mucosa, hair, nails) Observe and think
Dermatopathology Pathology – high degree of clinical pathological correlation Assess depth of lesion in skin
Bacterial Skin Disease Barrier – dry, tough, acidic, Ig in sweat, epidermal turnover every 28 days Normal Flora: Gm+, yeasts, anaerobes, Gm-
Bacterial Skin Diseases Impetigo Bullous and non-bullous Folliculitis/furuncle Erysipelas/cellulitis Necrotizing Fasciitis Toxin diseases: SSSS, Scarlet fever, toxic shocks Superantigen: Staph. aureus in atopic derm. Pseudomonas: warm, moist, alkaline
Impetigenization (bullous) of pre-existing dermatosis
Impetigenized Atopic (Non-bullous) Staph. > strep.
Erysipelas -Strep. pyogenes -Dermal infection -Asymmetrical, sharp demarcation -Spreading -Septic patient Treatment Oral – amoxacillin 500 QID x 14 days IV – if severe or recurrent, or co-morbidities
Cellulitis – haemorrhagic -usually Strep. pyogenes -deep dermal and sub- cutaneous Treat – as for erysipelas, but cover for Staph.
Necrotizing Fasciitis -Pain out of proportion to apparent lesion -Strep or multi-bacterial deep infection -Emergency debridement and multiple IV antibiotics
Meningococcal septicaemia Petechiae Purpura Necrosis Treatment -blood cultures -immediate IV antibiotics -lumbar puncture -support for gram negative endotoxic shock
Meningococcal Disease Septicemia vs meningitis - 40-70% vs 10% mortality Peaks: infancy to 5 years - Second peak age 15 Infection and Endotoxin and DIC cause damage Rash subtle at first - Erythema→purpura →necrosis - Search for petechiae / purpura - “any febrile child with a petechial rash should be considered to have meningococcal septicemia, and treatment should be commenced without waiting for further confirmation.”
SSSS primary Staph. infection conjunctivitis
Staph. Scalded Skin Syndrome SSSS – same child, back, sterile blisters -epidermolytic toxin mediated disease
31 yr. gay male admitted for biopsy of lymph node for expected lymphoma. Rash noted, dermatology consulted. Widespread papular eruption with adenopathy.
Soles of same patient. Your diagnosis?
Secondary syphilis -a systemic disease -order STS and treponemal tests -LP? Treatment -Benzathine penicillin 2.4 million units IM -Herxheimer reaction -follow STS -report disease -contact tracing -check for other venereal diseases
Secondary syphilis Condylomata lata
Viral Skin Disease DNA – tend to proliferate on skin RNA – tend to be erythemas/exanthems Exanthem – epidermal/skin Enanthem - mucosal
Definitions Exanthem(s) = Exanthema(ta), (Greek) A bursting out (ex) in flowers (anthema) Any dermatosis that erupts or “flowers” quickly Only the erythemas are numbered Includes papular, vesicular, pustular eruptions
Classic Exanthems Erythemas of Childhood 1 Rubeola - Measles 2 Scarlet Fever 3 Rubella – German Measles 4 Kawasaki disease 5 Erythema Infectiosum 6 Roseola Infantum - Exanthem Subitum
Human Herpes Virus 1 HSV-1 2 HSV-2 3 VZV 4 EBV 5 CMV 6 Roseola 7 ? 7 ? 8 Kaposi’s Sarcoma
Measles – morbilliform erythema Red measles = rubeola Koplick’s spots in oral mucosa, early
Rubella with post auricular nodes (German measles)
Erythema infectiosum = Parvo virus B19 = slapped cheek syndrome
Erythema infectiosum Reticulate erythema on arms Treatment – supportive Systemic -arthritis in adults -hydrops fetalis -anaemia
Toxic erythema -viral -scarlet fever drug acute collagen vascular disease
Herpes simplex, recurrent, post pneumococcal pneumonia
HSV 2, genital
Herpes virus – Tzanck smear – multinucleated giant cells
Eczema herpeticum HSV in atopic dermatitis
Herpes zoster = recurrence of Varicella Zoster virus
Herpes virus, treatment Acyclovir, famciclovir, valacyclovir Must treat early (72 hours) Front end load dose Shortens course and reduces severity Does not eliminate virus
MC in Atopic
Post herpetic Erythema Multiforme
Herald plaque - pityriasis rosea annular, NOT fungus Cause unclear, probably infectious (HHV7)
Pityriasis rosea Diagnosis -symmetrical discrete oval salmon-coloured papules and plaques, collarette scales Treatment -UVL -erythromycin 250 QID, early -hydrocortisone cream if itchy -lasts 6-12 weeks, no scars
Common (vulgar) warts
Plantar Wart -dermatoglyphics -micro-haemorrhage -lateral tenderness -demarcation -dermatoglyphics -micro-haemorrhage -lateral tenderness
Mosaic plantar warts
(Plantar) Wart, Treatment Summary Respect natural history First do no harm Cryotherapy Caustics: salicylic acid, lactic acid, cantharadine Other chemicals: imiquimod, fluorouracil Immunotherapy: DPCP Surgery: curette only, no desiccation, no excision No radiation
HIV – primary exanthem This rash not a problem. It’s the permissive effect of immune suppression that allows other infections and tumors to kill
Primary HIV Infection Lapins et al BJD 1996, 22 consecutive men HIV Exposure Acute illness 11–28 days, Seroconvert in 2–3wks Fever 22, pharyngitis21, adenopathy21, Exanthem day 1-5 of illness Upper trunk and neck, discrete non-confluent red macules and maculopapules in 17 / 22 Enanthem of palatal erosions in 8 / 22
Fungal Skin Infections Superficial and Deep Superficial Tinea plus location Tinea = dermatophyte Lives on keratin (non-viable) Tinea versicolour is misnomer = dimorphic yeast Hair and nail infections must be treated systemically (terbinafine, griseofulvin)
Tinea capitis – Trichophyton tonsurans
Id reaction from Tinea capitis
Lymphadenopathy with tinea capitis
Kerion – tinea capitis, not bacterial infection
Tinea pedis - interdigital
Tinea pedis – moccasin pattern
Tinea manuum – 1 hand, 2 feet
Tinea incognito – topical steroids
Tinea incognito from topical steroids
Tinea faciei
Onychomycosis = tinea unguium
Tinea – source of recurrent infection
Yeast infection
Tinea - Management Diagnosis Treatment Scrape KOH Fungal culture – 3 weeks Treatment Topical – azoles: clotrimazole, ketoconazole cream BID x 2-3 weeks, terbinafine cream similar Oral – must use for hair and nails. Terbinafine 250 mg. OD for 4-12 weeks for adult
Deep fungal infections – invade viable tissue N.A. Blastomycosis
Blastomycosis
Blastomycosis
Deep Fungal Infections Management Diagnosis Tissue culture Skin biopsy with special stains Treatment Amphotericin B, IV -if multi-organ infection Itraconazole, po -if minimal disease in healthy patient
Break Time
Eczema A morphological diagnosis based on observations of the inflammatory pattern in the skin Eczema is not an etiologic diagnosis Eczema is a subgroup of dermatitis Etiology: exogenous vs endogenous Acute signs: erythema, edema, edematous papules, vesicles, erosions, crusting, secondary pyoderma Chronic signs: lichenification, scales, fissures, dyspigmentation Borders usually ill-defined
Atopic Dermatitis endogenous To make a diagnosis of atopic dermatitis (Hanifin) - must have 3 or more major features: 1) pruritus 2) typical morphology and distribution flexural lichenification facial and extensor involvement in infants and children 3) chronic or relapsing dermatitis 4) personal family history of atopy Plus 3 or more minor features:
Endogenous - Pompholyx of Palms, sago vesicles, acute phase
Chronic palmar eczema, fissures and scale
Atopic dermatitis Anti-cubital lichenification Black skin
Atopic dermatitis – anticubital lichenification with impetigenization
Severe lichenification – ankles, chronic phase
Exogenous - allergic contact dermatitis, poison ivy, acute signs
Rhus radicans The rash The plant
Patch testing, to diagnose cause of allergic contact dermatitis
Impetigenized eczema – what is the cause?
Diagnosis = Scabies infant Eczema caused by infestation
Scabies Burrows, sole
Scabies Burrows - finger
Scabetic nodules in infant
Scabetic nodules, adult scrotum
Eczema - Treatment Remove or treat the cause General measures Topical Optimise the environment for healing Compress if moist, hydrate if dry Topical Corticosteroids: hydrocortisone, betamethasone, clobetasol BID max. frequency Ointments, creams, gels, lotions Systemic Prednisone: define endpoint, always warn of osteonecrosis Phototherapy
Scabies - treatment Permethrin 5% cream or lotion neck to toes overnight Treat all close contacts whether itchy or not Wash clothes and bed-sheets Set aside gloves for 10 days Nodules may persist few months May use topical steroid after mites dead
Psoriasis T-cell disease, Th1 inflammatory pattern Morphology Symmetry (endogenous) Plaque: sharply demarcated plaque with coarse scale across whole lesion. Guttate: drop-like or papular variant of plaque psoriasis Pustular (sterile) and erythrodermic forms are more inflammatory and unstable Erythrodermic – involves > 90% skin
Erythemato-squamous Diseases differential diagnosis Psoriasis Seborrheic dermatitis Pityriasis versicolour Pityriasis rosea Dermatophyte Parapsoriasis and Mycosis fungoides Pityriasis rubra pilaris Secondary Syphilis Chronic Dermatitis
Psoriasis plaques – symmetry, sharp demarcation, coarse scale across lesion
psoriasis normal skin
Psoriasis – trunk partially treated
Psoriasis – annular not ringworm
Psoriasis – guttate (drop-like or papular)
Guttate Psoriasis
Psoriasis on black skin
Psoriasis - flexural
Psoriasis - scalp
Psoriasis – toes and nails, NOT fungus, culture if in doubt
Psoriasis – palms – pustular (sterile)
Pustular Psoriasis – widespread, unstable patient and disease
Pustular psoriasis
Psoriasis -Treatment Consider exacerbating factors: stress, drugs, infection Consider stability of disease (pustular and erythrodermic) Koebner = isomorphic phenomenon Three Pillars of therapy Topical – creams, ointments, lotions, baths Scalp, extensors, flexures Steroids Calcipotriene Salicylic acid Tar Systemic –Pills and Injections Methotrexate, Acitretin, Cyclosporin, Biologicals Ultraviolet Radiation UVB –broad and narrow band, UVA, PUVA
Acne Etiology: heredity, hormones, drugs, ?diet Sebum – encourages growth of P. acnes Propionibacterium acnes – inflammation, initiates comedones Morphology “Noninflammatory” – comedones, open and closed Inflammatory – papule, pustule, nodule, abscess (“cyst”), scars...ulcers Microcomedo is probably the primary lesion
Androgens Sebum Comedogenesis Proprionibacterium acnes Diet Psychological Topicals Antibiotics Anti-androgens Isotretinoin Physical Exacerbating factors Rosacea Perioral dermatitis
Acne – lesion morphology
Acne – scarring Isotretinoin use -teratogen, not mutagen -depression real but rare -1 mg/kg/day x 4-5 months -beta-HCG, lipids, ALT -double contraception -record discussion
Acne abscess vs. cyst
Acne scars – pits and box-cars
Acne – severe Treatment -erythromycin -prednisone -isotretinoin – low dose and increase slowly
Ulcerative acne
Acne - Treatment Psychological impact General measures: avoid picking, not due to poor hygeine Mechanical –rubbing clothes and equipment Chemical – oils, chlorinated hydrocarbons Diet - glycemic index?, milk? Drugs that flare acne Lithium, anabolic steroids, catabolic steroids, dilantin, halogens, EGFRI’s Topicals Benzoyl peroxide 5% aq. gel, once daily, (bleach) Retinoids – comedonal acne, tretinoin cream or gel nightly, adapalene, tazarotene are 2nd generation retinoids Antibiotics – consider issue of resistance Oral Antibiotics: Tetra 500 BID, minocycline, erythromycin, clindamycin, trimethoprim – X 3 months Hormones in females Isotretinoin – (Accutane, Clarus) – only disease remitting agent
Hidradenitis suppurativa - axilla
Perioral dermatitis
Perioral Dermatitis Treatment Don’t be fooled by name, it’s acne not eczema Stop topical steroids Metronidazole 1% topical cream or gel, or topical antibiotic (erythro, clinda) Tetracycline 500 bid x 6-8 weeks Sun protection Reduce flare factors – fluoride in toothpaste
Rosacea – rhinophyma, papules and pustule
Rosacea Diagnosis Erythema and telangectasias Papulopustular Sebaceous hyperplastic Symmetrical – usually Central facial Ill-defined No significant scale Treatment -sun protect -reduce flare factors -stop topical steroids -Metronidazole cr. 1% nightly -Tetracycline 500 BID -surgery for rhinophyma -laser or IPL for telangectasia
Pruritus Itchy dermatoses eczematous dermatitis scabies and insect bites urticaria dermatitis herpetiformis lichen planus bullous pemphigoid psoriasis – sometimes
Systemic causes of Pruritus “itch without rash” chronic renal failure cholestasis Polycythemia pregnancy thyroid dysfunction malignancy - Hodgkins H.I.V. ovarian hormones separate itch nerves. ,unmyelinated slow C fibres
Mediators of Pruritus Histamine (H)-(from mast cell via various receptors)- itch mediated at H1 receptor substance P, tryptase opioid peptides-central or peripheral cytokines-IL-2,IF…. Prostaglandin E, serotonin
Drug reactions Acute onset Cephalo-caudal spread Antibiotics, anticonvulsants, NSAID’s Accurate history critical – graph drugs vs date Treatment stop offending drugs supportive care
Toxic Epidermal Necrolysis – Chinese herbal medication
Skin Cancer BCCa, SCCa, Melanoma include over 98% of skin cancers you will see Sunlight, UVB>UVA is major carcinogen
Cystic BCCa - Forehead
Basal Cell Carcinoma - Eyelid
Neglected BCCa - forehead
Superficial Multicentric BCCa Red plaque, sharp demarcation, irregular border
Keratoacanthoma pattern SCCa – sun damaged neck
Atypical Mole Rule out melanoma Biopsy -excise, conservative -incise -shave -excise, conservative -incise -punch
Melanoma – back, superficial spreading Melanoma-Canada 2008 (estimated) -4600 cases -910 deaths Asymmetry Border Colour Diameter Evolution Melanoma – back, superficial spreading
Melanoma - Prognosis Depth of invasion = Breslow thickness Most important for stage 1-2 melanoma Measured from granular layer of epidermis to deepest malignant cell, with ocular micrometer Regional Lymph-node Mets – stage 3 Distant Mets – stage 4
Melanoma – sole, amelanotic
Melanoma – Thumb, acral lentigenous
Cutaneous T-Cell Lymphoma = Mycosis Fungoides
Skin Cancer – Risk Factors Ultraviolet radiation UVB – 290 - 320 nm UVA – 320 – 400 nm Other Controllable Ionizing radiation Arsenic Tobacco Tar HPV Immune-suppression (permissive) HIV, Drugs
Skin Cancer - Treatment Biopsy if in doubt match method to depth (shave, punch, incision, excision) Curettage (BCCa, SCCa small, not Melanoma) may precede with shave excision electrodesiccation Surgical Excision Closure: fusiform, flap, graft Margin Control Ill-defined, critical real-estate, recurrent, aggressive Mohs’, frozen section Radiotherapy Other: chemotherapy (imiquimod), PDT
Mohs’ micrographic surgery