Derm Flashcards
Dx any dermal malignancy
Bx
Never shave
Dx any dermal malignancy
Bx
Never shave
Who gets skin CA
More sun
Pale skin
Features of melanoma
Assymetry Borders irregular Colours not uniform Diameter >6mm Evolving
Worst prognostic sign of melanoma
Growing
Dx melanoma
Full thickness Bx
Rx melanoma
Surgical removal including a significant amount of normal skin
IFN injection for widespread
Where does melanoma metastasize to
Brain
Who gets squamous cell skin CA
Sun
Organ transplant
- Long term immunosuppresive meds
What does SCC look like
Ulcer that doesn’t heal and continues to grow
Management of SCC
Bx and remove
MCC skin CA
Basal cell carcinoma
What does BCC look like
Waxy lesion that is shiny like a pearl
Dx BCC
Shave and bx
Rx BCC
Mohs micrographic surgery
What is Mohs micrographic surgery
Removal of skin CA under dissecting microscope with immediate frozen section
Lose very small amount of NL tissue
What is Mohs micrographic surgery best for
Delicate areas like eyelid or ear
Who gets Kaposi (HHV8)
AIDS (via sexual contact, NOT IVDU)
Where does Kaposi manifest
Skin
GI
Lung
What doesn Kaposi look like
Reddish/Purple lesions
More vascular
Cuboidal epithelium
CD4 in Kaposi
Rx Kaposi
Rx AIDS w/ antiretrovirals (goes away when CD4 ↑)
Vincristine or IFN intralesional injection
Chemo w/ liposomal doxorubicin if all else fails
What is actinic keratosis
Premalignant
High intensity sun exposure
What can actinic keratosis convert to
SCC
What is Imiquimod used for
Actinic keratosis
Molluscum contagiosum
Condyloma acuminatum
What is Imiquimod used for
Actinic keratosis
Molluscum contagiosum
Condyloma acuminatum
Who gets skin CA
More sun
Pale skin
Features of melanoma
Assymetry Borders irregular Colours not uniform Diameter >6mm Evolving
Worst prognostic sign of melanoma
Growing
Dx melanoma
Full thickness Bx
Rx melanoma
Surgical removal including a significant amount of normal skin
IFN injection for widespread
Where does melanoma metastasize to
Brain
Who gets squamous cell skin CA
Sun
Organ transplant
- Long term immunosuppresive meds
What does SCC look like
Ulcer that doesn’t heal and continues to grow
Management of SCC
Bx and remove
MCC skin CA
Basal cell carcinoma
Rare AE of Tacrolimus and pimecrolimus
Develop lymphoma
Dx BCC
Shave and bx
Rx BCC
Mohs micrographic surgery
What is Mohs micrographic surgery
Removal of skin CA under dissecting microscope with immediate frozen section
Lose very small amount of NL tissue
What is Mohs micrographic surgery best for
Delicate areas like eyelid or ear
Who gets Kaposi (HHV8)
AIDS (via sexual contact, NOT IVDU)
Where does Kaposi manifest
Skin
GI
Lung
What doesn Kaposi look like
Reddish/Purple lesions
More vascular
Cuboidal epithelium
CD4 in Kaposi
Rx Kaposi
Rx AIDS w/ antiretrovirals (goes away when CD4 ↑)
Vincristine or IFN intralesional injection
Chemo w/ liposomal doxorubicin if all else fails
What is actinic keratosis
Premalignant
High intensity sun exposure
What can actinic keratosis convert to
SCC
How to remove actinic keratosis
Curettage Cryotherapy Laser Topical 5-fluorouracil Imiquimod
What is Imiquimod used for
Actinic keratosis
Molluscum contagiosum
Condyloma acuminatum
What is seborrheic keratoses
Liver spots on elderly, benign
“stuck on” appearance
Removed w/ cryotherapy, surgery, laser for cosmetic reasons
What is atopic dermatitis (Eczema) associated with
Overactivity of mast cells and immune system
What is in the Hx of a pt w/ eczema
Asthma
Allergic rhinitis
FHx of atopic disorders
Onset
MC presentation of eczema
Pruritis and scratching
Often on face
Pathogenesis of eczema
Pruritis and scratching
Scaly, rough areas of thickened skin
Superficial staph infections
Where does eczema usually manifest
Face, neck, behind knee
Skin care in eczema
Moisturize
Avoid bathing, soap, washcloths
Cotton instead of wool
What is elevated in atopic dermatitis
IgE
Medical therapy of eczema
Topical steroids Tacrolimus and pimecrolimus (less AE than steroids) Antihistamines ABX when impetigo occurs UV light (severe recalcitrant disease)
Antihistamines for mild eczema
Cetirizine
Fexofenadine
Loratidine
Antihistamines for severe eczema
Doxepine
Hydroxyzine
Diphenhydramine
Rare AE of Tacrolimus and pimecrolimus
Develop lymphoma
What causes psoriasis
Abs attacking epidermis
Presentation of psoriasis
Silver scaly plaques
NOT itchy
Extensor surfaces
Extensive disease associated with depression
Rx local psoriasis
Topical high potency steroids Vitamin A and D ointment - Calcipotriene Coal tar Pimecrolimus and tacrolimus on delicate areas
Steroids used in local psoriasis
Fluocinonide
Triamcinolone
Betamethasone
Clobetasol
Rx extensive psoriasis
UV light
Anti-TNF
MTX
Pityriasis rosea features
Idiopathic transient dermatitis
Herald patch that disseminates
Spares palms and soles
Rx symptomatic Pityriasis rosea
Steroids or UV
Differentiate Pityriasis rosea from secondary syphilis
Syphilis is VDRL or RPR positive in all cases
MCC contact dermatitis
Poison ivy
Rx w/ steroids
Features of seborrheic dermatitis
Hypersensitivity to dermal infection w/ noninvasive dermatophytes
Increased in AIDS and parkinson
Rx seborrheic dermatitis
Topical steroids AND antifungals
What drugs are pemphigus vilgaris associated with
ACEIs
Penicillamine
Phenobarbitol
PCN
Most accurate test for cellulitis
Inject sterile sale and aspirate for Cx
Staph > strep
Most accurate test for pemphigus vulgaris
Bx w/ auto-Abs
Rx pemphigus vulgaris
Systemic steroids
Azathioprine or mycophenolate
Rituximab or IVIG if refractory
Why is bullous pemphigoid less severe than pemphigus vulgaris
Bullae stay intact (less loss of fluid and infection)
Mouth not involved
Most accurate test for bullous pemphigoid
Bx w/ immunofluorescent stain
Best initial therapy for bullous pemphigoid
Prednisone
Wean off w/ azathioprine, cyclophosphamide, mycophenolate
Mild bullous pemphigoid responds to
Erythromycin
Dapsone
Nicotinamide
What does PCT usually affect
Backs of hands and face
What is in the Hx of a pt w/ PCT
Chronic liver disease (hep C, alcoholism)
Estrogen use
Fe overload (hemochromatosis)
Most accurate test for PCT
Increased uroporphyrins in 24hr urine collection
What is the defect in PCT
Deficiency of uroporphyrin decarboxylase
Rx PCT
Rx underlying cause (stop estrogen, stop alcohol)
Remove Fe w/ phlebotomy
Features of impetigo
“Honey coloured”
Weeping, crusting, oozing, draining skin
Causes of impetigo
Staph
Strep (group A beta hemolytic)
Erysipelas and impetigo can cause
Glomerulonephritis but not rheumatic fever
Rx mild impetigo
Topical
- Mupirocin
- Retapamulin
- Bacitracin
Rx severe impetigo
Oral
- Dicloxacillin
- Cephalexin
Rx impetigo due to community acquired MRSA
Doxy
Clinda
TMP/SMX
Why is erysipelas more severe than impetigo
Deeper in the skin
What causes erysipelas
Strep > staph
Presentation of erysipelas
Bright red hot swollen lesion on face
Leukocytosis
Treatment rule for erysipelas
Treat for staph and strep unless there is a definitive diagnosis
Rx mild erysipelas (same as for cellulitis, folliculitis, furuncles, carbuncles)
Diclox, cephalexin, cefadroxyl
PCN allergic: erythro, clarithro, clinda
MRSA: Doxy, clinda, TMP/SMX
Rx severe erysipelas (same as for cellulitis, folliculitis, furuncles, carbuncles)
Ox, clox, cefazolin
PCN allergic: Clinda, vanco
MRSA: vanco, linezolid, dapto, tige, ceftaroline
What does cellulitis look like
Warm, red, swollen, tender
Legs > arms
Most accurate test for cellulitis
Inject sterile sale and aspirate for Cx
Staph > strep
Features of folliculitis, furuncles, carbuncles
Folliculitis is small and mild hair follicle infection
Furuncle is small abscess
Carbuncle is collection of furuncles
Get around PCN rash in skin infections
Use cephalosporins
Get around PCN anaphylaxis in mild skin infections
Macrolides, clinda, doxy, TMP/SMX
Get around PCN anaphylaxis in severe skin infections
Vanco, linezolid, dapto, tige, ceftaroline
What is a severe skin infection
Fever
Chills
Bacteremia
Best initial test for fungal infection
KOH prep
Most accurate test for fungal infection
Fungal Cx
Best initial therapy for fungal infection (no hair or nail)
Topical antifungal agent
Best initial therapy for fungal infection with hair or nail involvement
Terbinafine
Itraconazole
What are topical antifungal agents
Clotirimazole Ketoconazole Miconazole Nystatin (candida only) Ciclopirox
AE ketoconazole
Antiandrogenic
Oral can cause gynecomastia
Best initial test/most accurate test for vaginal fungal disease
Same as oral
If presentation is clear then next best step is topical antifungal
Drug hypersensitivity presentation
Morbilliform rash
Erythema multiforme
SJS
TEN
Drugs that can cause any HS presentation
PCNs Sulfas Allopurinol Phenytoin Lamotrigine NSAIDs Rifampin Quinidine
Drugs that cause skin HS can also cause
Hemolysis
Interstitial nephritis
Drug induced thrombocytopenia
Causes of chronic urticaria
Pressure, cold, vibration
Rx urticaria
Antihistamines (non-sedating)
Sedating antihistamines are for anaphylaxis
Appearance of erythema multiforme
5cm is lyme
Appearance of SJS
Mucous membrane involvement
May lead to resp failure
Rx w/ IVIG
Appearance of TEN
Rash, mucous membrane involvement
Positive nikolsky sign
Rx w/ IVIG
What is “fixed” reaction
Drug HS only happens on one part of body
Aside from drugs, what is erythema multiforme associated with
Mycoplasma
HSV
What is staph scalded skin syndrome and toxic shock syndrome
Different severeties of a reaction to a staph surface toxin
Features of SSSS and TSS
Hypotension
Renal dysfunction
Liver dysfunction
CNS involvement
Rx SSSS and TSS
Supportive care Antistaph ABX (Ox, Naf, cefazolin) ABX do not reverse disease
Progression of acne rx
Benzoyl peroxide (topical ABX if ineffective)
ADD topical vit A
Oral ABX if fail
ADD oral vit A to oral ABX
Important to consider when administering vit A derivative in acne
Teratogenic so do a pregnancy test
