Dermatology Flashcards
What is included in the atopic disease triad?
- Eczema
- Allergic rhinitis
- Asthma
Usually starts in childhood
Altered immune reaction in genetically susceptible people when exposed to certain triggers - causes an increase in IgE production
Atopic dermatitis (Eczema)
Triggers for Atopic dermatitis (Eczema)
Heat
Perspiration
Allergens
Contact irritants (wool, nickel, food)
Hallmark of atopic dermatitis (eczema)
pruritus!
Erythematous, ill-defined blisters/papules/plaques that later dries, crusts over and scales
Atopic dermatitis (eczema)
Atopic dermatitis (eczema) is most commonly found:
Flexor Creases
Antecubital fold and popliteal folds
Special characteristic of atopic dermatitis (eczema)
Dermatographism - localized development of hives when the skin is stroked
Sharply defined discoid/coin shaped lesions found on the dorsum of the hands, feet, and extensor surfaces (knees, elbows)
Nummular Eczema
Atopic dermatitis
Management of atopic dermatitis (eczema)
- Topical corticosteroids, antihistamines for itching
2. Topical calcineurin inhibitors (Tacrolimus, Pimecrolimus) are alternatives for steroids
Seborrheic dermatitis may be due to a hypersensitivity to:
Malassezia furfur
Seborrheic dermatitis is most commonly seen in:
Adult men
Seborrheic dermatitis occurs most common in areas of:
High sebaceous gland over secretion - scalp, face, eyebrows, body folds
Erythematous plaques with fine white scales seen on infants heads
Cradle Cap - Seborrheic Dermatitis
Erythematous plaques with fine white scales seen on the scalp, eyelids, beard/mustache, etc.
Seborrheic dermatitis
Management of seborrheic dermatitis
Topical: selenium sulfide, sodium sulfacetamide, ketoconazole (shampoo or cream)
Systemic: oral antifungals - itraconazole, fluconazole, ketoconazole, terbinafine
Triggers for dyshidrosis
Sweating
Emotional stress
Warm and humid weather
Metals (ex. nickel)
Pruritic “tapioca-like” tense vesicles on the soles, palms, and fingers
Dyshidrosis
Management of dyshidrosis
Topical steroids - ointment preferred
Cold compresses
Skin thickening in pts with eczema secondary to repetitive rubbing/scratching
Lichen simplex chronicus
Scaly, well-demarcated, rough hyperkeratotic plaques with exaggerated skin lines
Lichen simplex chronicus
Management of lichen simplex chronicus
Avoid scratching!
Topical steroids (high strength)
Antihistamines
Occlusive dressings
Has an increased incidence with Hepatitis C
Lichen planus
The 5 P’s of lichen Planus
Purple, polygonal, planar, pruritic papules
Lichen planus most commonly seen on:
Flexor surfaces, skin, mouth, scalp, genitals, nails and mucous membranes
Koebner’s Phenomenon
New lesions at site of trauma
Seen in psoriasis and lichen planus
Fine white lines on the skin lesions or on the oral mucosa - nail dystrophy
Wickham Striae
Seen in lichen planus
Management of lichen planus
Topical corticosteroids
Antihistamines for pruritus
Rash will usually spontaneously resolve in 8-12 mo
Urticaria and angioedema are _____ mediated and usually occur immediately after offending drug/trigger is taken
IgE
Erythema multiforme is a __________ reaction that is usually delayed and cell mediated
Morbilliform
Most common type of drug reaction/skin eruption
Exanthematous / Morbilliform Rash
Generalized distribution of “bright-red” macules and papules that coalesce to form plaques - typically begins 2-14 days after medication initiation
Drug eruption
Exanthematous/Morbilliform Rash
2nd most common type of drug eruption
Urticaria
3rd most common type of drug eruption
Erythema multiforme
Most common type of drug eruption
Exanthematous/morbilliform
Most common offending drugs with urticaria
Antibiotics and NSAIDs
Management of drug induced exanthematous/morbilliform rash
Oral antihistamines
Management of drug induced urticaria / angioedema
Systemic corticosteroids, antihistamines
Management of drug induced erythema multiforme
Symptomatic therapy
Topical steroids, oral antihistamines
Associated with Human Herpes Virus 7
Pityriasis Rosea
This rash can mimic syphilis, so an RPR should be ordered if the pt is sexually active
Pityriasis Rosea
Solitary salmon-colored macule on the trunk, followed by general exanthem 1-2 weeks later
Herald Patch
Pityriasis Rosea
Very pruritic salmon-colored papules with collarette scaling along cleavage lines in a christmas tree pattern
Pityriasis Rosea
Management for pityriasis rosea
None needed
PO antihistamines, topical corticosteroids as needed
Can use UVB phototherapy if severe and started early
Keratin hyperplasia due to T cell activation leads to greater epidermal thickness and increased epidermis turnover
Psoriasis
Raised, dark-red plaques/papules seen with thick silver/white scales
Psoriasis
Plaque Psoriasis is most common seen on the:
Extensor surfaces
Elbows, knees, scalp, nape of neck
25% of plaque psoriasis also have:
Nail pitting
Yellow-brown discoloration until the nail (oil spot)
Punctate bleeding with removal of plaque/scale
Auspitz sign
Seen with psoriasis and actinic keratosis
Deep, yellow non-infected pustules that evolve into red macules on palms/soles
Pustular psoriasis
Erythematous rash that lacks scales, seen in body folds (groin, gluteal fold, axilla)
Inverse psoriasis
Inflammatory arthritis that includes joint stiffness > 30 minutes relieved with activity. May also have “sausage digits”
Psoriatic arthritis
Radiograph deformity seen with psoriatic arthritis
Pencil in cup deformity
Management for psoriasis
Topical steroids first line
Moderate-severe: phototherapy
Systemic treatment: Methotrexate
Most common cause of erythema multiforme
Secondary to herpes simplex infection
Multiple target-like lesions that spares the mucosa
Erythema Multiforme Minor
Multiple target-like lesions that includes mucosal involvement
Erythema Multiforme Major
Treatment of erythema multiforme
Typically resolves after 2 weeks
Can give topical steroids and antihistamines
Most common medications causing SJS and TEN
Allopurinol Sulfonamides Lamotrigine NSAIDs Anticonvulsants
SJS affects _______% of body surface area
< 10%
TEN affects _______% of body surface area
> 30%
Prodrome of fever, malaise, myalgias followed by lesions on face and trunk. Bullous and vesicle formation begins days after
SJS/TEN
Gentle pressure to the skin causes sloughing
Nikolsky Sign
Seen in SJS/TEN
Main cause of death with SJS/TEN
Sepsis and shock secondary to infection
Treatment for SJS/TEN
Admit to hospital, preferably to burn unit
Supportive care is mainstay
Chronic widespread autoimmune blistering skin disease primarily of the ELDERLY
Bullous pemphigoid
Bullous pemphigoid will have ________ of Nikolsky sign
Absence
Bullous pemphigoid is caused by an ______ autoimmune attack on the epithelial basement membrane
Type II HSN
IgG
Management of bullous pemphigoid
Systemic corticosteroids
Antihistamines
Azathioprine (immunosuppressant)
4 main pathophysiologic factors for acne vulgaris:
- Increased sebum production
- Clogged sebaceous glands
- P. acne overgrowth
- Inflammatory response
Small, non inflammatory bumps from clogged pores
Comedones
Acne vulgaris
Treatment for mild acne
Topical retinoids
Benzoyl peroxide
Topical abx (Clindamycin)
OCPs
Treatment of rmoderate acne
Oral abx (Doxy, Minocycline, Erythromycin, Clindamycin)
Treatment of severe (nodular/cystic) acne
Isotretinoin
S/E of isotretinoin
Highly teratogenic
Hepatitis, increased triglycerides/cholesterol, psych side effects
What must be done before prescribing isotretinoin?
Highly teratogenic
Obtain at least 2 pregnancy tests prior to initiation and monthly
Must be on 2 forms of contraception
Symptoms due to increased capillary permeability and increased vasomotor instability with lesion formation
Rosacea
Triggers for Rosacea
EtOH Hot/cold temperature Hot drinks Hot baths Spicy foods
Acne-like rash, erythema, facial flushing, telangiectasia
Rosacea
Absence of comedones distinguishes it from acne
Rosaceae
Treatment for rosacea
Metronidazole first line
Topical abx
Can do oral abx if severe
Lifestyle modifications for rosacea
Sunscreen, avoid toners, camphor and triggers
Most commonly seen in fair-skinned elderly with prolonged sun exposure
Actinic keratosis
Seborrheic keratosis
Premalignant condition to squamous cell carcinoma
Actinic keratosis
Most common premalignant skin condition
Actinic keratosis
Dry, rough, scaly “sandpaper” skin lesion or erythematous, hyperkaratotic
Actinic keratosis
May present with a projection (horn) on the skin
Actinic keratosis
Diagnosis of actinic keratosis
Punch or shave biopsy
Management of actinic keratosis
Observation, surgical
Topical 5-fluorouracil, imiquimod
Most common benign skin tumor
Seborrheic keratosis
Small papule/plaque velvety warty lesions with a greasy/stuck on appearance
Seborrheic keratosis
Intense itching, especially in the occipital area, papular urticaria may been seen
Lice
White oval-shaped egg capsules at the base of the hair shafts
Nits
Lice
Management of lice
Permethrin topical drug of choice
Safe in children > 2 y/o
If lice in hair: permethrin shampoo (leave on 10 min)
If pubis/body: permethrin lotion at least 8-10 hours
Second line management of lice and S/E
Lindane
Neurotoxic - headaches, seizures
Do not use after showering
Instructions for mom with children with lice
Bedding/clothing should be laundered in hot water with detergents and dried in hot drier for 20 minutes.
Toys that cannot be washed should be placed in airtight plastic bags x 14 days
Scabies cannot survive off the human body for _____ days
> 4
Intensely pruritic papules, vesicles and linear burrows
Scabies
Commonly found in the intertriginous zones including web spaces between fingers/toes and scalp
Scabies
Increased intensity of rash at night
Scabies
Diagnosis of scabies
Clinical diagnosis
Can scrape burrows with mineral oil to identify mites or eggs under microscopy
Treatment of scabies
Permethrin topical
Apply topically from neck to soles of feet for 8-14 hours before showering
Repeat application after 1 week is recommended
Second line tx for scabies
Linedane (cheaper)
Do not use after bath/shower
May cause seizures
Teratogenic, not used in breastfeeding women or children < 2 y/o
Instructions for scabies
All clothing, bedding, should be placed in plastic bag at least 72 hours then washed and dried using heat
Spider bite with local burning and erythema, will have an erythematous margin around the ischemic center, or a “red halo”
Brown Recluse spider bites
Spider bite after 24-72 hours that will have hemorrhagic bullae that undergoes eschar formation
Brown recluse spider bite
Management of brown recluse spider bite
- Local wound care - clean area with soap and water, apply cold packs to bite site
- Pain control - NSAIDs, opiates
- Dermal necrosis - debridement
Spider bite that may cause muscle pain, spasms and rigidity. Muscle pain most commonly affects the extremities, back and abdomen
Black widow spider bites
Classic appearance is a blanched circular patch with a surrounding red perimeter and central punctum (target lesion)
Black widow spider bitet
Management of black widow spider bite
- Wound care and pain control
- Opioids +/- muscle relaxants if severe
- Antivenom used if not responsive to other medications
Major risk factor for basal cell carcinoma
Exposure to UV light
Pearly papule with a telangiectatic vessel that typically occurs on face
Basal cell carcinoma
Diagnosis of basal cell carcinoma
Shave biopsy
Basal cell carcinoma where papule ulcerates
Rodent ulcer
Treatment of basal cell carcinoma
Rarely metastasize
Removal
Connective tissue cancer caused by Human Herpes Virus 8
Kaposi Sarcoma
Cancer most commonly seen in immunosuppressed pts or HIV
Kaposi Sarcoma
Macular, papular, nodular, plaque like brown/pink/red violaceous lesions
Kaposi Sarcoma
Management of Kaposi Sarcoma
HAART therapy
Radiation therapy for local dz
Most dangerous form of skin cancer, as it has high risk for metastasis
Melanoma
ABCDE rule of melanomas
Asymmetry Border irregularity Color variation Diameter > 6 mm Evolving shape, size, or color
Diagnosis of melanoma
Excisional biopsy with 1-3 mm of the surrounding skin and part of subcutaneous fat
Treatment of melanoma
Surgical removal
Adjunctive tx with interferon alpha can prolong survival in high risk groups
Non-scarring immune-mediated hair loss targeting the anagen hair follicles
Alopecia Areata
Alopecia areata is commonly associated with other _________ disorders
Autoimmune
Thyroid, Addison’s disease
Smooth discrete circular patches of complete hair loss that develops over a period of weeks
Alopecia Areata
Short hairs broken off a few mm from the scalp at the margins of the patches with tapering near the proximal hair shaft
Exclamation point hairs
Alopecia Areata
Management of alopecia areata
Local - intralesional corticosteroids
Extensive - topical corticosteroids
Progressive loss of the terminal hairs on the scalp in a characteristic distribution
Androgenetic alopecia
___________ is the key androgen leading to androgenetic alopecia
Dihydrotestosterone
Treatment of androgenetic alopecia
- Minoxidil (best if used early)
- Oral Finasteride
S/E: decreased libido, sexual or ejaculatory dysfunction
Nail infection by various fungi, occurs most commonly on the great toes
Onychomycosis
Management of onychomycosis
Itraconazole and terbinafine
However, associated with hepatotoxicity and drug interactions
Infection of the nail margin
Paronychia
Paronychia most commonly occurs after __________
Skin trauma
Biting nails, cuticle damage
Most common organism in paronychia
Staph aureus
GABHS
Candida if slow growing
Closed-space infection of the fingertip pulp - progression of a paronychia
Felon
Management of paronychia
Warm soaks
Antibiotics (Cephalexin)
Incision and drainage if needed
HPV infects keratinized skin, causing excessive proliferation and retention of the stratum corneum causing papula formation
Condyloma acuminatum
Genital warts
Condyloma acuminatum
Tiny, painless, papules evolve into soft, fleshy, cauliflower-like lesions
Condyloma acuminatum
Management of condyloma acuminatum
Most warts resolve spontaneously within 2 years if immunocompetent
Chemical, salicylic acid, cryotherapy, laser and podophyllin
Exanthem with prodrome of high fever for 3-5 days, which resolves before onset of a rose pink, maculopapular blanchable rash on the trunk/back progressing to the face
Roseola Infantum
Sixth disease
Only childhood exanthem that starts on the trunk
Roseola infantum
Sixth disease
Management of roseola infantum (sixth disease)
Supportive
Anti Inflammatories
Antipyretics (to prevent febrile seizures)
Oral exanthem with vesicular lesions with erythematous halos in the oral cavity leading to vesicular, macular or maculopapular lesions on the distal extremities (often includes palms and soles)
Hand Foot & Mouth Disease
Coxsackie A Virus
Management of hand foot and mouth disease
Supportive
Antipyretics
Topical lidocaine
Rashes that affect palms/soles
HF and M
RMSF
Syphilis (secondary)
Janeway lesions (endocarditis)
What causes mumps?
Paramyxovirus
Low grade fever, myalgias, headache, parotid gland pain and swelling
Mumps
Management of mumps
Supportive
Anti-inflammatories
Symptoms usually last 7-10 days
Complications of mumps
Orchitis in males
Acute pancreatitis in children
URI prodrome with high fever and 3 C’s - cough, conjunctivitis, and coryza (stuffy nose)
Rubeola (Measles)
Small red spots in buccal mucosa with pale blue/white center
Koplik Spots
Rubeola (Measles)
Morbilliform (maculopapular) brick-red rash on face beginning at hairline, moving to extremities that darkens and coalesces
Rubeola (Measles)
Rash usually lasts 7 days, fading from top to bottom. Fever often concurrent with rash
Rubeola (Measles)
Low grade fever, cough, anorexia, lymphadenopathy (posterior, cervical, posterior auricular). Pink, light-red spotted maculopapular rash on face and extremities
Rubella (German Measles)
3 day rash
Rubella (German Measles)
Small red macules or petechiae on soft palate
Forchheimer Spots
Rubella (German Measles)
Compared to rubeola, spreads more rapidly and does not darken or coalesce
Rubella (German Measles)
Diagnosis of rubella (german measles)
Clinical
Rubella-specific IgM antibody via enzyme immunoassay
Management of Rubella
Anti-inflammatories
Supportive
Rubella (german measles) is teratogenic, especially:
In the first trimester
Can lead to sensorineural deafness, TTP (blueberry muffin rash), mental retardation, heart defects
Erythema infectiosum (fifth disease) is caused by:
Parvovirus B19
Stuff nose, fever followed by a slapped cheek rash on face with circumoral pallor
Erythema infectiosum (fifth disease)
Lacy reticular rash on the extremities (especially upper) that spares the palms and soles
Erythema infectiosum (fifth disease)
Diagnosis for erythema infectiosum (fifth disease)
Serologies
Management of erythema infectiosum (fifth disease)
Supportive
Anti-inflammatories
Have to be aware of erythema infectiosum (fifth disease), because it may cause aplastic crisis in pts with:
Sickle cell disease OR
G6PD deficiency
Clusters of vesicles on an erythematous base, dew drops on a rose petal in different stages (macules, papules, vesicles, pustules, and crusted lesions). Usually pruritic.
Varicella (chicken pox)
Management of varicella (chicken pox)
Symptomatic treatment
Molluscum contagiosum is due to:
Poxviridae family (benign viral infxn)
Single or multiple dome-shaped, flesh-colored to pearly-white, waxy papules with central umbilication
Molluscum contagiosum
Treatment for molluscum contagiosum
No treatment needed in most cases
May do: curettage, cryotherapy, imiquimod, topical retinoids if severe
HPV infects keratinized skin, causing excessive proliferation and retention of the stratum corneum - papule formation
Verrucae (warts)
Firm, hyperkeratotic papules between 1-10 mm with red-brown punctuations. Thrombosed capillaries are pathognomonic
Common and plantar warts (verrucae)
Numerous, small, discrete, flesh-colored papules measuring 1-5 mm in diameter. Flat
Flat warts (verrucae)
Management of verrucae (warts)
Most resolve spontaneously within 2 years if immunocompetent
May use OTC salicylic acid and plasters
Can do cryotherapy (liquid nitrogen), etc.
Most common etiologies of erysipelas/cellulitis
Streptococci (GABHS)
Staph aureus
Infection of the skin that presents with erythema, edema, warmth and tenderness
Cellulitis / Erysipelas
______ involves deeper dermis and subcutaneous fat
Cellulitis
_______ involves only upper dermis
Erysipelas
Raised with clear line of demarcation between infected and uninfected tissue
Erysipelas
Treatment for cellulitis
- elevate area and keep skin hydrated
- those with drainage should be treated for MRSA (clindamycin, TMP/SMX or doxy)
- Those without drainage should be treated for MSSA (clindamycin, cephalexin, dicloxacillin)
Treatment for erysipelas
Those with mild infxn can be treated with penicillin, macrolide, cephalexin or clindamycin
Improvement should be noted after 3 days of treatment
Highly contagious superficial vesiculopustular skin infection that typically occurs at site of superficial skin trauma
Impetigo
Impetigo occurs primarily on exposed surfaces of the:
Face and extremities
Risk factors for impetigo
Warm
Humid conditions
Poor personal hygiene
Vesicles, pustules that have a characteristic honey colored crust
Nonbullous impetigo
Most common causes of impetigo
Staph aureus
Vesicles form large bullae (rapidly), which rupture and leave thin “varnish-like crusts”, fever and diarrhea also
Bullous impetigo
Management of impetigo
- Mupirocin (Bactroban) topical drug of choice TID x 10 days
- Wash area gently with soap and water
Management of impetigo if extensive disease or systemic symptoms (fever)
Systemic abx - cephalexin
Dicloxacillin, clindamycin, ertyrhomycin, azithromycin
Velvety hyperpigmented lesions found on neck and axilla that is usually associated with insulin resistance
Acanthosis Nigricans
Management of acanthosis nigricans
Screen for diabetes
Treat underlying cause
Topical retinoids, vitamin D analogs, and hydroquinone can be used for cosmetic purposes
Chronic abscess of apocrine sweat glands or sebaceous cysts with tract formation. Red tender inflammatory nodules/abscesses
Hidradenitis suppurativa
Most common areas of hidradenitis suppurativa
Axilla, groin, under breasts or anogenital areas
Management of hidradenitis suppurativa
- Mild: topical clindamycin
- Deep, recurrent infxns: punch debridement
- Painful abscess - I and D
- surgical excision
- watch obesity (common cause)
Subcutaneous benign tumor of adipose tissue. Soft, symmetric, painless, easily mobile, palpable mass in the subcutaneous tissue
Lipoma
Mobile masses of fibrous tissue and keratinous (cottage cheese like) substance
Sebaceous cyst
Management of sebaceous cyst
No tx needed
Abx and I and D if becomes infected
Cosmetic removal
Hypermelanosis (hyperpigmentation) of sun exposed areas of the skin
Melasma
Melasma usually seen on:
Face and neck
Diagnosis of melasma
Wood’s Lamp - appearance unchanged under black light
Management of melasma
SUNSCREEN Topical bleachers (hydroquinone, topical retinoids, azelaic acid)
Tender abscess with drainage on or near the gluteal cleft near the midline of the coccyx or sacrum with small midline pits
Pilonidal disease
Management of pilonidal disease
I and D
May surgical remove tracts if recurrent
Skin intact, superficial, nonblanchable redness that does not dissipate after pressure is relieved
Stage I pressure ulcer
Epidermal damage extending into dermis. Shallow ulcer that resembles a blister or abrasion
Stage II pressure ulcer
Full thickness of the skin and may extend into the subcutaneous layer
Stage III pressure ulcer
Deepest, extends beyond the fascia into the muscle, tendon or bone
Stage IV pressure ulcer
Purple area of discolored skin
Suspected deep tissue injury
Ulcer covered with slough or eschar, making depth undetermined
Unstageable pressure ulcer
Management of pressure ulcers
- Optimize nutritional status, offer pain control
- Wet to dry dressings, hydrogels
- May need surgical debridement for stages III and IV
Type I HSN (IgE) or complement-mediated edematous reaction of the dermis and/or SQ tissues
Urticaria
Mast cells release histamine causing vasodilation of venules and edema of dermis and SQ tissue
Urticaria
Blanchable, edematous pink papules, wheals or plaques (oval, linear or irregular)
Urticaria
Localized urticaria where the skin is rubbed (urticaria pigmentosa)
Darier’s sign
Management of urticaria
Oral antihistamines treatment of choice
Autoimmune destruction of melanocytes leading to skin depigmentation
Vitiligo
Irregular discrete macules and patches of total depigmentation. Commonly involves the dorsum of the hands, axilla, face, fingers, body folds and genitalia
Vitiligo
Management of vitiligo
- Localized: topical corticosteroids
2. Disseminated: systemic phototherapy
Superficial hair follicle infection with singular or clusters of small papules or pustules with surrounding erythema
Folliculitis
Most common organism for folliculitis
Staph aureus
Treatment for folliculitis
- Topical Mupirocin, clindamycin, erythromycin
Annual, scaling lesions and broken hair shafts. Inflamed plaques with multipel pustules with scarring and alopecia
Tinea capitis (fungal) Ringworm
Treatment for tinea capitis
PO griseofulvin
Terbinafine, itraconazole
Pruritic, scaly eruption rash between toes
Tinea pedis (athlete’s foot)
Management for tinea pedis
Topical antifungals
PO griseofulvin if uneffective
Diffusely red rash on the groin or on the scrotum
Tinea cruris (jock itch)
Management of tinea cruris
Topical antifungal
PO griseofulvin in ineffective
Erythematous plaques (circular rash with clear center and defined borders), scaling, cracking and vesicles
Tinea corporis
Management of tinea corporis
Topical antifungal
PO griseofulvin if ineffective
Diagnosis of fungal infections
KOH smear
Wood’s lamp
Overgrowth of the yeast Malassezia furfur
Tinea versicolor
Diagnosis of tinea versicolor
KOH prep from skin scraping - spaghetti and meatball appearance
Wood’s lamp - yellow green fluorescence
Management of tinea versicolor
Topical antifungals - selenium sulfide, sodium sulfacetamide, zinc pyrithione, azoles
PO itraconazole or fluconazole if widespread