Triggers of Dishydrosis
Sweating, emotional stress, warm weather, metals
Pruritus "tapioca pudding" tense vesicles on palms, soles and fingers
Management of Dishydrosis
Topical steroids (high strength)- ointments preferred
What is atopic dermatitis linked with?
Hay fever, allergy, allergic rhinitis, asthma, & other atopic dx
Altered immune reaction in genetically susceptible population when exposed to triggers --> T-cell mediated immune activation with increase in IgE production
Triggers of atopic dermatitis?
heat, perspiration, allergens, and contact irritants
What is the hallmark clinical manifestation of atopic dermatitis?
Pruritus- "itch-scratch cycle"
Tiny, erythematous, edematous ill-defined blisters --> dries/crusts over and scales. MC in flexor creases (anticubital & popliteal folds)
Sharply defined coin-shaped lesions on dorsal hand, feet extensor surface
Management of atopic dermatitis
High strength topical steroids & antihistamines for itching
Skin thickening in patients with eczema secondary to repetitive rubbing/scratching
Lichen simplex chronicus
Scaly, well-demarcated rough plaques with exaggerated skin lines
Lichen simplex chronicus
Management of LSC?
Topical steroids (high strength) and avoid scratching
Where does lichen planus develop?
Flexor surfaces of extremities, mucous membranes on skin mouth, scalp, genitals, or nails
In which disease do you see lichen planus more often?
What are the 5 P's for lichen planus?
Purple, polygonal, planar, pruritic papules with fine scales
What type of lesions can be seen in the oral mucosa with lichen planus?
Lacy lesions (Wickham striae)
Management of lichen planus?
Topical steroid ointment and antihistamines
Herald patch (solitary salmon-colored macule) on trunk --> general exanthem 1-2 weeks later with smaller, round/oval salmon-colored papules with white circular (collarette) scaling along cleavage lines. VERY PRURITIC
What rash pattern is seen with Pityriasis rosea?
Management for Pityriasis rosea
What is the pathophysiology of psoriasis?
Keratin hyperplasia (proliferating cells in the stratum basale and stratum spinosum due to T-cell activation & cytokine release). Leads to epidermal thickening and continuous turnover of the dermis
Plaques seen in Psoriasis?
- MC type
- raised dark red plaques/papules with thick silver/white scales
- found on extensor surfaces and scalp
- Nail pitting in 25%
What signs/phenomenon are seen with Psoriasis?
Auspitz sigmn and Koebner's phenomenon
Clinical manifestations of Pustular psoriasis?
Deep, yellow non-infected pustules --> red macules on palms/soles
Clinical manifestations of Guttate psoriasis?
- small, erythematous papules with fine scales, discrete lesions, and confluent plaques
What inflammatory condition is seen with psoriasis?
Sx of psoriatic arthritis?
- Stiffness >30mins relived with activity
- Sausage digits
- X-ray: pencil in cup deformity
Management of psoriasis?
- Topical steroids, tar-based anthralin, Vit. D analnogs & retinoid
- UBV light therapy , immune agents
Occurs in areas of high sebaceous glands over secretion (scalp, face, eyebrows, body folds)
What do you have a hypersensitivity too in seborrheic dermatitis?
What does seborrheic dermatitis present as in infants?
Erythematous plaques with fine white scales common on the scalp (dandruff)
Management of seborrheic dermatitis?
Selenium sulfide, sodium sulfacetamide, ketoconazole (shampoo or cream), steroids, zinc pyrithione
Type I HSN (IgE) reaction of dermis or SQ tissues
Triggers of Urticaria (Hives)?
- insect bites
What is the pathophys of Urticaria (Hives)?
Mast cells release histamine causing vasodilation of venules --> edema of dermis and SQ tissues
Blanchable, edematous pink papules, wheals, or plaques that are oval, linear, or irregular
What is Darier's sign?
Localized urticaria appearing where skin is rubbed (histamine induced)
What is the tx of choice for Urticaria (Hives)?
Acute, self-limiting type IV HSN rxn most common in adults 20-40 y/o
What infections are assoicated with erythema multiforme?
- HSV most common
- s. pneumo
What meds are associated with erythema multiforme?
- sulfa drugs
What type of lesion is pathognomonic of erythema multiforme?
TARGET (iris) lesions
Dull, "dusty-violet" red, purpuric macule/vesicle or bullae in center surrounded by pale edematous rim & peropheral halo. Patient often FEBRILE
What are the guidelines for erythema multiforme minor?
- target lesions distributed acrally
- no mucosal membrane lesions
What are the guidelines for erythema multiforme major?
- target lesions with involvement of >1 mucous membranes (oral, genital, ocular mucosa)
- <10% BSA acrally --> centrally
- no epidermal detachment
Management of erythema multiforme?
- Symptomatic: discontinue drug causing rash
- can also use steroid mouthwashes for oral lesions
What most commonly causes SJS and TEN?
Drug eruptions esp. Sulfa and antioconvulsant meds and infections like Mycoplasma, HSV, HIV, malignancy
What % of sloughing of BSA is seen in SJS and TEN?
- SJS: <10%
- TEN: >30%
What sign is positive in SJS and TEN?
Nikolsky sign: pushing a blister causes further separation of the dermis
What are the clinical manifestations of SJS and TEN?
- Fever & URI sx
- Widespread blisters begin on trunk/face
- erythematous/pruritic macules >1 mucous membrane with epidermal detachment
Management of SJS and TEN?
treat like severe burns
4 main pathophysiologic factors of acne vulgarus
- Increased sebum production: MC due to puberty (increased androgens)
- Clogged sebaceous glands
- Propionibacterium acne overgrowth in blocked pores
- Inflammatory response
Clinical manifestations of acne vulgaris?
- Inflammatory papules or pustules
- Nodular or cystic acne --> often heals with scarring
What is an open comedone?
Blackhead --> due to incomplete blockage
What is a closed comedone?
Whitehead --> complete blockage
What is seen in mild acne?
Comedones w or w/o small amounts of papules or pustules
What is seen in moderate acne?
Comedones with larger amounts of papules and/or pustules
What is seen in severe acne?
Nodular or cystic acne
What is the management for mild acne?
- topical retinoids
- benzyl peroxide
- topical abx
What is the management for moderate acne?
Same as mild acne but can add oral abx like doxy or minocycline and spironolactone (anti-androgen agent)
What is the management for severe acne?
What are the side effects of Isotretinoins?
- Highly teratogenic
- psych side effects
- increased triglycerides/cholesterol
- MUST obtain 2 pregnancy tests prior to starting & monthly while on it
What is considered "adult acne"?
Triggers of Rosacea?
- increased temperature
- hot drinks
- hot/cold weather
- hot baths
- spicy foods
Acne-like rash with erythema, facial flushing, telangiectasia, skin coarsening, papulopustules with burning/stinging
What distinguishes rosacea from acne?
Absence of comedones
What is first line treatment for rosacea?
Topical metronidazole and clonidine may be used for flushing
Lifestyle modifications for rosacea?
- avoid toners
- astringent menthols
What population is actinic keratosis most commonly seen in?
fair-skinned elderly with prolonged sun exposure
What is actinic keratosis a premalignant condition to?
squamous cell carcinoma
Dry, rough, scaly "sandpaper" skin lesions or edematous, hyperkeratotic plaques
How do you diagnose actinic keratosis?
epidermal/dermal cells with large hyper chromatic nuclei
Management of actinic keratosis?
- Surgical: cryotherapy or dermabrasion
- medical: 5FU or imiquimod
What is the pathophysiology of vitiligo?
Autoimmune destruction of melanocytes that leads to skin depigmentation
Irregular macules & patches of total depigmentation
Management of vitiligo?
- Systemic phototherapy (may aid in repigmentation)
- laser therapy (effective on limited areas)
What is the most common benign skin tumor that is seen in fair-skinned elderly with prolonged sun exposure?
Small papule/plaque velvety warty lesion with "greasy/stuck on appearance"
varied colors: flesh-colored, brown, black, grey
Management of seborrheic keratosis?
Benign= NO TREATMENT NEEDED! :)
Can use cryotherapy for cosmetic reasons
Most common type of skin cancer in the US
Basal cell carcinoma
Where is basal cell carcinoma most commonly seen?
Fair-skinned with prolonged sun expsoure and xeroderma
Locally invasive but very low incidence of metastasis
Basal cell carcinoma
Flat, firm area with small, raised, translucent/pearly/waxy papule with central ulceration & raised, rolled borders
MC on face/nose/trunk
Often friable (bleeds easily)
Basal cell carcinoma
How do you dx basal cell carcinoma?
Punch or shave biopsy
What is the tx of choice for basal cell carcinoma?
2nd MC skin cancer
Squamous cell carcinoma
What often preceeds squamous cell carcinoma?
- Actinic keratosis
- HPV infection
- Sun/envrio exposure
- Xeroderma pigmentosum
Where on the body is SCC most commonly found?
Lips, hands, neck & head
Pathophysiology of SCC?
Malignancy pf keratinocytes of skin/mucous membranes: hyperkeratosis & ulceration
What is Bowen's disease?
SCC in situ --> slow growing
Red, elevated nodule with white scaly or crusted bloody margins
Squamous cell carcinoma
How do you dx SCC?
Biopsy: epidermal & dermal cells with large, pleomorphic, hyperchromatic nuclei
Tx of choice for SCC?
What % of cases of malignant melanoma are associated with UV radiation?
Agressive with high METS potential
In which population is malignant melanoma most commonly seen?
Caucasian patient with light hair/eye color
Also pt's with Xeroderma pigmentosum
"ABCDE" of malignant melanoma
- Borders: irregular
- Color: variation (dark blue, black)
- Diameter: >6mm
- Evolution (suspect in a lesion with recent/rapid change in appearance)
What is the most important prognostic factor for METS in malignant melanoma?
What is the MC skin cancer death?
How do you dx malignant melanoma?
Full-thickness wide excisional bx with LN biopsy
Management of malignant melanoma?
Excision (lymph node bx or dissection)
What is the MC neoplasm seen in HIV/immunocompromised?
Connective tissue cancer caused by HHV-8
Macular, popular, nodule, plaque-like brown/pink/red or violaceous lesions
Management for Kaposi sarcoma?
Highly contagious superficial vesiculopustular skin infection primarily on exposed surface of face and extremities
Usually multiple lesions
Risk factors of impetigo?
- warm, humid conditions
- poor personal hygeine
Where does impetigo most often occur?
@ sites of superficial skin trauma (eg insect bites)
What is nonbullous impetigo?
- Impetigo contagiosa: vesicles, pustules
- characteristic "honey-colored crusts"
- MC type!
What is the MC and 2nd MC cause of nonbullous impetigo?
1st: S. aureus
What is bullous impetigo?
Vesicles form large bullae (rapidly) --> rupture --> thin "varnish like crusts"
What is the MC cause of bullous impetigo?
Is bullous impetigo common?
NO, but usually seen in newborn/young children
What is ecthyma impetigo?
Ulcerative pyoderma caused by GABHS (heals with scarring)
What is the DOC for impetigo?
What tx is used for extensive impetigo dx?
Systemic abx (Cephalexin, Dicloxacillin)
What is cellulitis?
Acute, spreading superficial infection of dermal, subcutaneous tissues
What bacterias cause cellulitis?
S. aureus and group A strep
H. influenza/S. pneumonia in children
How does cellulitis usually occur?
Break in the skin
Local manifestations of cellulitis?
macular erythema (margins flat, not sharply dermarcated), swelling, warmth, and tenderness
Tx for cellulitis?
Abx for 7-10 days: Cephalexin or Dicloxacillin
Systemic manifestations of cellulitis?
Fever, chills, +/- tender lymphadenopathy, +/- lymphangitis (erythematous streaking), myalgias
vesicles, bullae, hemorrhage, and necrosis may form
What abx should you use for cellulitis caused by a cat bite? :)
Augmentin for Pasteurella multocida