USMLE First Aid 2016 Dermatology – Flashcards

Unlock all answers in this set

Unlock answers
question
A 30-year-old non-smoker presents with bilateral puffiness and swelling of the fingers and joint pain. Cold exposure and stress cause episodes of blanching and cyanosis of the fingers. She is not on any medications.
answer
Scleroderma-CREST syndrome
question
This presents as a triad of autoimmunity, noninflammatory vasculopathy and collagen deposition with fibrosis commonly showing sclerotic, tight, puffy skin without wrinkles and finger pitting. Can show sclerosis of renal, pulmonary, CV and GI systems
answer
Scleroderma (systemic sclerosis)
question
This form of scleroderma involves widespread skin involvement with rapid progression, early visceral involvement associated with anti-Scl-70 Antibody:
answer
diffuse scleroderma
question
Anti-DNA topoisomerase I antibody:
answer
Anti-Scl-70 antibody
question
This scleroderma presents with limit skin involvement confined to fingers and face and is associated with CREST Syndrome and anti-centromere antibodies
answer
Limited scleroderma
question
What is CREST syndrome:
answer
-Calcinosis -Raynaud phenomenon -Esophageal dysmotility -Sclerodactyly -Telangiectasia
question
Decreased blood flow to skin due to small arteriolar vasospasm in response to cold or stress, color changes from white (ischemic) to blue (hypoxia) to red (reprofusion)
answer
Raynaud disease
question
This is secondary to a disease process like mixed CT disease, SLE or CREST showing digital ulceration color change at finger tips and can be treated with Ca channel blockers:
answer
Raynaud syndrome
question
3 layers of skin:
answer
-Epidermis -Dermis -Subcutaneous fat (hypodermis/subcutis)
question
5 layers of epidermis:
answer
-Stratum Corneum (keratin) -Stratum Lucidum -Stratum Granulosum -Stratum Spinosum (desmosomes) -Stratum Basale (stem cell site)
question
These prevent paracellular movement of solutes and are composed of claudins and occludins. they are the closest to the surface:
answer
Tight junction (zone occludes)
question
These are below the tight junctions and form "belt" connecting actin cytoskeletons of adjacent cells with CADherins (Ca-dependent adhesion proteins) -remember loss of E-cadherin promotes mets
answer
Adherens junction (Belt desmosome, zonula adherens) -contain actin filaments
question
These are structural support via intermediate filament interactions. Autoantibodies are directed here in pemphigus vulgarism:
answer
desmosome (spot desmosome, macula adherens) -contain desmoplakin and cytokeratin
question
These are channel proteins called connexons that permit electrical and chemical communication between cells:
answer
Gap junction -connexon with central channel
question
These maintain integrity of basolateral membrane by binding to collagen and laminin in the basement membrane:
answer
Integrins
question
These connect keratin in basal cells to underlying basement membrane. Autoantibodies to these are seen in bullous pemphigoid
answer
Hemidesmosome
question
A flat lesion with well circumscribed change in skin color <1cm (i.e. Freckle)
answer
Macule
question
These are macules >1cm (i.e. large birthmark or congenital nevus)
answer
Patch
question
These are elevated solid skin lesions <1cm (Ie mole-nevus or acne)
answer
Papule
question
These are papules >1cm (i.e. Psoriasis)
answer
Plaque
question
These are small fluid-containing blisters <1cm (i.e. chickenpox-varicella, shingles-zoster)
answer
Vesicle
question
These are large fluid-containing blisters >1cm (i.e. bullous pemphigoid)
answer
Bulla
question
These are pus containing vesicles (i.e. pustular psoriasis)
answer
Pustule
question
These are transient smith papule or plaque (i.e. Hives-urticaria)
answer
Wheal
question
These are flaking off stratum corneum (i.e. eczema, psoriasis, SCC)
answer
Scale
question
These are dry exudate (i.e. impetigo)
answer
Crust
question
This term describes increased thickness of the stratum corneum (i.e. in psoriasis or calluses)
answer
Hyperkeratosis
question
This term describes hyperkeratosis with retention of nuclei in stratum corneum (i.e. in psoriasis)
answer
Parakeratosis
question
This describes increased thickness of stratum granulosum seen in Lichen planus
answer
Hypergranulosis
question
This describes separation o epidermal cells (i.e. seen in Pemphigus vulgaris)
answer
Acantholysis
question
This describes epidermal hyperplasia (increase in spinosum layer) (i.e. in acanthuses nigricans)
answer
Acanthosis
question
This disorder describes normal melanocyte number with decrease melanin production due to deficiency in tyrosinase active or defective tyrosine transport, with an increase risk of skin cancer:
answer
Albinism
question
This shows hyper pigmentation associated with pregnancy (mask of pregnancy) or OCP use
answer
Melasma (chloasma)
question
This shows irregular areas of complete depigmentation caused by autoimmune destruction of melanocytes
answer
Vitiligo
question
What follicles are affected in acne:
answer
pilosebaceous
question
Obstruction of pilosebaceous follicles without inflammation is called:
answer
comedones
question
Pruritic eruption commonly on skin flexures associated with other atopic disease like asthma, allergic rhinitis, food allergies with elevated IgE in serum typically presenting on face in infancy and then antecubital fosssae
answer
-Atopic dermatitis (eczema)
question
This type IV hypersensitivity reaction follows exposure to an allergen, lesions occur at the site of contact (will see clear markings of contact)
answer
Allergic contact dermatis
question
This is a comm, benign finding on the skin, melanoma can arise in congenital atypical forms:
answer
Melanocytic nevus
question
What nevi are papular?
answer
Intradermal
question
What nevi are flat macules:
answer
junctional
question
This is composed of papulse and plaques with silvery scaling, especially on the knees and elbows.
answer
Psoriasis
question
These are the findings of what disease: ? stratum spinosum ? stratum granulosum preservation of the nuclei within the hyperkeratotic stratum corneum extension of the rete pegs into the basal layer neutrophils in the stratum corneum infiltration of T cells and dendritic cells in plaques
answer
Psoriasis
question
This sign is given if pinpoint bleeding spots from exposure of dermal papillae when psoriatic scales are scraped off
answer
Auspitz sign
question
This inflammatory facial skin disorder is characterized by erythematous papules and pustules but no comedones. May be associated with facial flushing in response to external stimuli (ETOH or heat or Demodex folliculorum (mite) presence)
answer
Rosacea
question
Which form of rosacea can cause rhinophyma (bulbous deformation of the nose)
answer
Phymatous
question
This describes Flat, greasy, pigmented squamous epithelial proliferation with Keratin-filled cysts (horn cysts) that looks stuck on. Lesionsare on the head, trunk and extremities commonly benign neoplasm of olde rpatients
answer
Seborrheic keratosis
question
This sudden appearance of multiple seborrheic keratoses indicating underlying malignancy (typically GI adenocarcinoma or lymphoid) is called what:
answer
Leser-Trelat sign
question
A 72-year-old male visits his dermatologist with several brown plaques on his neck, back, shoulders and arms. He says that the vast majority of the lesions appeared over the past month. Upon physical examination, the lesions appear greasy and coin-like and are of variable size. The appearance of this patient's lesions is associated with which of the following
answer
Leser-Trelat sign associated with internal malignancy
question
These are caused by HPV, they are soft, tan-colored cauliflower-like papules of epidermal hyperplasia, hyperkeratosis, koilocytosis
answer
Verrucae (warts)
question
Warts on genitals:
answer
Condyloma acuminatum
question
These are pruritic wheals that form after Type I hypersensitivity mast cell degranulation, characterized by superficial dermal edema and lymphatic channel dilation.
answer
Uritcaria (hives)
question
This is a rare blood vessel malignancy typically occurring in the head, neck and breast region of elderly pts on sun-exposed areas or associated with radiation therapy and chronic post mastectomy lymphedema. these are very aggressive and very difficult to resect
answer
Angiosarcoma
question
Vinyl chloride and arsenic are associated with what malignancies:
answer
Hepatic angiosarcoma
question
These benign capillary skin papules found in AIDs pts caused by bartonella henselae infection frequently mistaken for Kaposi, can differentiate by presence of neutrophilic infiltrate
answer
Bacillary angiomatosis
question
These are benign capillary hemangioma of the elderly that do not regress and are associated with increased age
answer
Cherry hemangioma
question
These cavernous lymphangioma of the neck are associated with Turner syndrome
answer
Cystic hygroma
question
This benign, painful, red-blue tumorr, commonly under fingernails arises from modified smooth muscle cells of thermoregulatory glomus body;
answer
glomus tumor
question
This endothelial malignancy most commonly of the skin but also the mouth, GI tract and respiratory tract is associated with HHV-8 and HIV is frequently mistaken for bacillary angiomatosis, but has lymphocytic infiltrate
answer
Kaposi sarcoma
question
This polypoid lobulated capillary hemangioma that can ulcerate and bleed is associated with pregnancy and trauma
answer
Pyogenic granuloma
question
Benign capillary hemangioma of infancy appears in the first few weeks of life, grows rapidly then regresses spontaneously by 5-8 years
answer
Strawberry hemangioma
question
This is a very superficial skin infection from Staph a or Strep P, is highly contagious with honey colored crusting
answer
Impedigo
question
This highly contagious superficial skin infection presents with bullae and is usually caused by staph a
answer
Bullous impetigo
question
This infection involves the upper dermis and superficial lymphatics, usually from Strep pyogenes, presents with well-defined demarcation between infected and normal skin
answer
Erysipelas
question
This acute, painful, spreading infection of deeper dermis and subcutaneous tissues, usually from strep p or staph a often starting with a break in skin from trauma or another infection
answer
cellulitis
question
This is a collection of pus from a walled-off infection within deeper layers of skin, typically from Staph a infection
answer
Abscess
question
This is a deeper tissue injury, usually from anaerobic bacteria or S pyogenes resulting in crepitus from methane and Co2 production "flesh-eating bacteria" causes bullae and purple color of the skin
answer
Necrotizing fasciitis
question
This exotoxin mediated infection destroys keratinocyte attachments in stratum granulosum only (intra-epdermal desmosomes) (vs toxic epidermal necrolysis which destroys epidermal-dermal jx) is characterized by fever and generalized erythematous rash with sloughing of the upper layers of the epidermis that heals completely
answer
Staph Scalded Skin Syndrome
question
This sign is dislodgement of intact superficial epidermis by a small force, indicating a plane of cleavage in the skin
answer
Nikolsky sign (seen in SSS)
question
Staph SSS typically affects what individuals:
answer
-Newborns and children -Adults with renal insufficiency
question
These are umbilicated papules from a poxvirus frequently seen in children but maybe sexually transmitted in adults
answer
Molluscum contagiosum
question
This presents with multiple crops of lesions in various stages from vesicles to crusts and can reactivate in a dermatomal distribution unless it is disseminated
answer
VZV varicella: chickenpox vs zoster: shingles
question
This precancerous irregular, white, painless plaque on lateral tongue that cannot be scraped off seen with EBV infection occurs in HIV pts or immunosuppressed so transplant.
answer
Hairy leukoplakia
question
This is a potentially fatal autoimmune skin disorder caused by IgG directed against desmoglein that forms flaccid intraepidermal bullae caused by acantholysis (keratinocytes in stratum spinosum) and oral mucosal involvement. Fluorescence reveals antibodies around epidermal cells in a reticular (net-like) pattern and is Nikolsky sign +
answer
Pemphigus vulgaris
question
This is less severe disorder involves IgG against hemidesmosomes in the basement membrane causing Tense blisters containing eosinophils affecting skin but sparing oral mucosa, nikolsky -, linear pattern at epidermal-dermal junction on Immunoflourescence
answer
Bullous pemphigoid
question
A 50-year-old female presents to her physician with vesicles and tense blisters across her chest, arms, and the back of her shoulders. Physical examination reveals that blistering is not present in her oral mucosa, and the epidermis does not separate upon light stroking of the skin. The patient most likely suffers from a hypersensitivity reaction located
answer
Bullous pemphigoid
question
This presents as pruritic papules, vesicles, and bullae on elbows with deposits of IgA at tips of dermal papillae often associated with Celia disease and can be treated with dapsone and gluten free diet:
answer
Dermatitis herpetiformis
question
This is associated with infection (mycoplasma pneumo or HSV), drugs (sulfa-drugs/beta lactams, phentoin), cancer, auto immune disease where pet presents with multiple type of lesions (macules, papules, vesicles, target lesions)
answer
Erythema multiforme
question
This is characterized by fever, bullae formation and necrosis, sloughing of the skin at dermal-epidermal junction, high mortality rate typically involving two mucous membranes (eyes and mouth) and may appear like erythema multiform. Associated with horrible adverse drug interaction
answer
Stevens-johnson syndrome
question
This is a more severe form of SJS with ;30% of body surface involved
answer
Toxic epidermal necrolysis (TEN)
question
This is described as epidermal hyperplasia causing symmetric, hyper pigmented thickening of skin, especially in axilla or on neck, and is highly associated with insulin resistance (diabetes, obesity, Cushing syndrome) or visceral malignancy (Gastric adenocarcinoma)
answer
Acanthosis nigricans
question
This premalignant lesion is caused by sun exposure, showing small/rough/erythematous or brownish papules or plaques with risk of Squamous cell carcinoma proportional to free of epithelial dysplasia
answer
Actinic keratosis
question
A 33-year-old archeologist was on a dig in Arizona. After returning home he developed flu-like symptoms with a nonproductive cough, mild chest pain, fever, and painful red nodules are his lower extremities. The are no infiltrates or effusions on CXR. A mild eosinophilia is noted on peripheral blood.
answer
Erythema nodosum
question
This painful inflammatory lesion of subcutaneous fat usually on anterior shins is often idiopathic but can be associated with underlying disease (sarcoid, coccidiodmycosis, histo, TB, Strep, leprosy, IBD) is a IV hypersensitivity reaction
answer
Erythema nodosum
question
This Pruritic, Purple, Polygonal, Plantar, Papules, and Plaques are associated with
answer
Lichen Planus
question
Mucosal involvement (white reticular lines) with lichen plans is called:
answer
Wickham striae
question
This skin disorder is associated with HCV and shows sawtooth infiltrate of lymphocytes at dermal-epidermal junction
answer
Lichen Planus
question
"Herald patch" followed days later by other scaly erythematous plaques often in a "christmas tree" distribution on the trunk showing multiple plaques with collarette scale that is self resolving in 6-8 weeks
answer
Pityriasis rosea -treat with sun exposure?
question
Acute cutaneous inflammatory reaction due to excessive UVB radiation causing DNA mutations and inducing apoptosis of keratinocytes. This can lead to impetigo, skin cancers (basal cell carcinoma, squamous cell carcinoma, melanoma)
answer
Sunburn -UVA are your tanning rays
question
The most common skin cancer:
answer
Basal cell carcinoma
question
This cancer is highly associated with sun-exposure is locally invasive, but rarely metastasizes. Shows pink, pearly nodules, commonly with telangiectaiass, rolled borders, central crusting or ulceration, and can appears non healing ulcers with infiltrative growth or as scaling plaques if superficial. They have "palisading" nuclei
answer
Basal cell Carcinoma
question
This is the second most common skin cancer
answer
Squamous cell carcinoma
question
This is associated with excessive exposure to the sun, immunosuppression and occasionally arsenic exposure that commonly appears above the neck and on hands. It is locally invasive, may spread to lymph nodes and will rarely metastasize. Ulcerative red lesions with frequent scales are characteristic and is associated with chronic draining sinuses:
answer
Squamous cell carcionma
question
This scaly plaque is a precursor to squamous cell carcinoma:
answer
Actinic keratosis
question
This is a variant of squamous cell carcinoma that grows rapidly in 4-6weeks and may regress spontaneously over months:
answer
Keratoacanthoma
question
This common skin tumor has significant risk of metastasis, is S-100+ and BRAF mut driven, associated with skin exposure so fair-skinned pts are at greater risk. Look for Asymmetry, Border irregularity, color variation, diameter ;6mm and Evolution over time
answer
Melanoma
question
4 types of Melanoma:
answer
-Superficial spreading -Nodular -Lentigo maligna -Acral lentiginous
question
What correlates with risk of metastasis for melanoma:
answer
Depth of invasion
question
Primary treatment for melanoma:
answer
Excision
question
Primary treatment for unresectable melanoma in BRAF V600E+ pts:
answer
Verumafenib (BRAF kinase inhibitor)
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New