Derm Flashcards
ID the epidermis, dermis, and hypodermis
ID the layer
Stratum corneum
Epidermis is derived from [embryonic structure]
Dermis is derived from [embryonic structure]
Hypodermis is derived from [embryonic structure]
Epidermis is derived from ectoderm
Dermis is derived from mesoderm
Hypodermis is derived from mesoderm
Name the layers of the epidermis from superficial to deep
Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Basement membrane
“Come let’s get sunburnt”
The stem cell layer of the epidermis is the _
The stem cell layer of the epidermis is the stratum basale
The [epidermis layer] is anuclear or “dead”
The stratum corneum is anuclear or “dead”
The antigen presenting immune cells of the skin are _
The antigen presenting immune cells of the skin are langerhan cells
Merkel cells of the skin are a type of [cell]
Merkel cells of the skin are a type of neuroendocrine cells
There are two layers of the dermis, the _ and _
There are two layers of the dermis, the papillary dermis and reticular dermis
ID the layers of the epidermis
Meissner corpuscles and immune cells are found in the [layer of the dermis]
Meissner corpuscles and immune cells are found in the papillary dermis
Sebaceous glands, apocrine glands, hair follicle roots, and ruffini corpuscles are found in the [dermis layer]
Sebaceous glands, apocrine glands, hair follicle roots, and ruffini corpuscles are found in the reticular layer
The tightest of all cellular junctions are the _
The tightest of all cellular junctions are the tight junctions
* We find these in the BBB and blood-testis barrier
* Also called zonula occludens
* They prevent water loss
_ are cellular junctions which allow for cellular electrochemical communication in locations like the cardiac myocytes
Gap junctions are cellular junctions which allow for cellular electrochemical communication in locations like the cardiac myocytes
[Cellular junctions] are the structural connectors between cells
Desmosomes are the structural connectors between cells
* Also called macula adherens
* They attach to keratin
[Cellular junctions] connect epithelial cells to the basement membrane
Hemidesmosomes connect epithelial cells to the basement membrane
[Cellular junctions] connect the actin cytoskeletons of adjacent cells
Adherens junctions connect the actin cytoskeletons of adjacent cells
* They are found between adjacent epithelial cells
Claudins and occludins compose [cellular junctions]
Claudins and occludins compose tight junctions
[Cellular junctions] are composed of cadherins
Adherens junction are composed of cadherins
* Cadherens
Desmoplakin, desmocollin, desmoglein make up [cellular junctions]
Desmoplakin, desmocollin, desmoglein make up desmosomes
Hemidesmosomes are made up of [cellular component]
Hemidesmosomes are made up of integrins
Gap junctions are made up of [cellular components]
Gap junctions are made up of connexons
Hyperkeratosis is _
Hyperkeratosis is increased thickness of the stratum corneum
* Ex: psoriasis, verrucae, calluses
_ is retention of nuclei within the stratum corneum
Parakeratosis is retention of nuclei within the stratum corneum
* Ex: psoriasis, actinic keratosis
_ is a classic example of hypergranulosis with rete ridge changes
Lichen planus is a classic example of hypergranulosis with rete ridge changes
* (And wickham striae)
* Recall that hypergranulosis means increased thickness of the granulosum layer
Spongiosis refers to _
Spongiosis refers to accumulation of fluid within the intercellular spaces
* Ex: atopic dermatitis, allergic contact dermatitis
Epidermal hyperplasia of the stratum spinosum is called _
Epidermal hyperplasia of the stratum spinosum is called acanthosis
* Ex: acanthosis nigricans, psoriasis
Acantholysis refers to _
Acantholysis refers to separation of cells in the epidermis without basement membrane involvement
* Affects desmoglein 1
* Nikolsky positive, tombstoning, floating keratinocytes
* Ex: pemphigus vulgaris, SSS
A macule is a _
A macule is a flat discoloration < 1 cm
* Ex: freckle, solar lentigo, tinea versicolor
A flat discoloration > 1 cm is called a _
A flat discoloration > 1 cm is called a patch
* ex: large congenital nevus, port wine stain
An elevated skin lesion < 1 cm is called _
An elevated skin lesion < 1 cm is called papule
* ex: acne, molluscum contagiosum
A plaque is a _
A plaque is an elevated skin lesion > 1 cm
* ex: psoriasis, BCC
_ is a fluid filled blister < 1 cm
Vesicle is a fluid filled blister < 1 cm
* Ex: varicella zoster, herpes simplex
A fluid filled blister > 1 cm is called _
A fluid filled blister > 1 cm is called bulla
* Ex: pemphigus vulgaris, bullous pemphigoid, burns
A pus filled vesicle is called a _
A pus filled vesicle is called a pustule
* Ex: acne, folliculitis
_ is a raised pink papule or plaque that is transient
Wheal is a raised pink papule or plaque that is transient
* Ex: allergic contact dermatitis, hives, bug bites
_ is a thickened stratum corneum that is dry, flaky, white/silver
Scale is a thickened stratum corneum that is dry, flaky, white/silver
* Ex: psoriasis, eczema, actinic keratosis, SCC
Crust refers to exudate or secretions that have dried; common in [infectious condition]
Crust refers to exudate or secretions that have dried; common in impetigo
_ are abrasions and trauma to skin via mechanical force
Excoriations are abrasions and trauma to skin via mechanical force
Lichenification is _
Lichenification is thickening of skin, accentuation of skin markings
* Often result of repeated excoriation
* Lichen simplex chronicus
Hematomas are [blanching/ non-blanching] blood collections
Hematomas are non-blanching blood collections
* Ex: petechiae, ecchymosis, purpura
Impetigo is a bacterial skin condition of the [layer]
Impetigo is a bacterial skin condition of the epidermis (superficial)
Two types of impetigo are _ and _
Two types of impetigo are superficial impetigo and bullous impetigo
“Honey-colored” crusted skin lesions are classic for [condition]
“Honey-colored” crusted skin lesions are classic for superficial impetigo
* Highly contagious
* Nikolsky negative
Superficial impetigo is most commonly caused by [bug(s)]
Superficial impetigo is most commonly caused by staph aureus or strep pyogenes
Bullous impetigo involves fluid-filled blisters that are nikolsky sign _
Bullous impetigo involves fluid-filled blisters that are nikolsky sign positive
Bullous impetigo is most commonly caused by [bug(s)]
Bullous impetigo is most commonly caused by staph aureus
* Exfoliative toxin cleaves desmoglein 1 –> stratum granulosum cleavage –> blisters
Complications of impetigo caused by strep pyogenes include _
Complications of impetigo caused by strep pyogenes include rheumatic fever and PSGN
Impetigo should be treated with [abx]
Impetigo should be treated with nafcillin (penicillinase resistant penicillin)
Sandpaper rash that begins on the neck and then moves to the trunk and extremities is classic for _
Sandpaper rash that begins on the neck and then moves to the trunk and extremities is classic for scarlet fever
* Group A strep
* Pastia lines (red lines in wrist/elbow)
* Strawberry tongue
_ is a bacterial infection of the deep dermal and subcutaneous tissue
Cellulitis is a bacterial infection of the deep dermal and subcutaneous tissue
* Either strep pyogenes or staph aureus
_ is a bacterial infection of the superficial dermis
Erysipelas is a bacterial infection of the superficial dermis
[Erysipelas/ Cellulitis] is a deeper skin infection
Cellulitis is a deeper skin infection
[Erysipelas/ Cellulitis] has more defined borders
Erysipelas has more defined borders
Cellulitis is classic in [regions]
Cellulitis is classic in lower extremities
* Streaking erythema towards lymph nodes
Erysipelas most common occurs in [regions]
Erysipelas most common occurs in lower extremities and face
Systemic symptoms [will/ will not] be present with cellulitis and erysipelas
Systemic symptoms will be present with cellulitis and erysipelas
Non-purulent cellulitis is caused by [bacteria]
Non-purulent cellulitis is caused by strep pyogenes
Purulent cellulitis is caused by [bacteria]
Purulent cellulitis is caused by staph aureus
Erysipelas is caused by [bacteria]
Erysipelas is caused by strep pyogenes
_ is a diffuse staphylococcal infection of the epidermis which is nikolsky sign positive
Staphylococcal scalded skin syndrome is a diffuse staphylococcal infection of the epidermis which is nikolsky sign positive
Staph scalded skin syndrome damage to the epidermis is mediated by _
Staph scalded skin syndrome damage to the epidermis is mediated by exfoliative exotoxin
* Cleaves desmoglein 1 –> stratum granulosum cleavage –> blisters
Staph scalded skin syndrome is more common in babies, children, or adults with [risk factor]
Staph scalded skin syndrome is more common in babies, children, or adults with renal insufficiency
* Kidneys can’t efficiently filter out the toxin
[SJS/ SSS] can have oral involvement
SJS can have oral involvement
* Versus SSS will have no mucosal involvement and will heal completely without scarring (only affects the epidermis)
An abscess is a collection of pus in the [skin layers]
An abscess is a collection of pus in the dermis and epidermis
An abscess is almost always caused by [bacteria]
An abscess is almost always caused by staph aureus
* May present as a fluctuant warm fluid collection with systemic symptoms
Necrotizing fasciitis is an infection of the _
Necrotizing fasciitis is an infection of the fascia
How will necrotizing fasciitis present?
- Crepitus from gas production by the bacteria
- Pain out of proportion on physical exam
- Bullae and purple discoloration of skin
Herpes viruses are [structure]
Herpes viruses are double stranded DNA viruses
Name some buzzwords for herpes infections
- Tzanck smear
- Multinucleated giant cells
- Intranuclear eosinophilic cowdry A inclusions
- “Dew drop on a rose petal”
Primary infection with varicella zoster virus is known as _ ; secondary infection is _
Primary infection with varicella zoster virus is known as chicken pox ; secondary infection is shingles
Shingles involves a prodrome of sx such as _ before the rash develops
Shingles involves a prodrome of sx such as fever, malaise, localized pain before the rash develops
* Prodrome is caused by cytokines
_ sign is when shingles involves the tip of the nose
Hutchinson sign is when shingles involves the tip of the nose
Ramsay Hunt syndrome is caused by VZV involvement of _
Ramsay Hunt syndrome is caused by VZV involvement of facial nerve
* Also called herpes zoster oticus
A child with chicken pox should not be given aspirin due to the risk of [complication]
A child with chicken pox should not be given aspirin due to the risk of Reye’s syndrome
Herpes simplex encephalitis primarily affects the [lobe]
Herpes simplex encephalitis primarily affects the temporal lobe –> language dysfunction, memory loss, behavioral changes
How will HSV 2 present?
HSV 2 presents with prodromal genital pain followed by ulcers and inguinal lymphadenopathy
Diagnosis?
HSV 1
[HSV-1, HSV-2, VZV] can be transmitted via airborne droplets
VZV can be transmitted via airborne droplets
HSV-1 goes dormant in the _
HSV-1 goes dormant in the trigeminal ganglia
HSV-2 goes dormant in the _
HSV-2 goes dormant in the sacral ganglia
VZV goes dormant in the _
VZV goes dormant in the dorsal root ganglia or trigeminal ganglia
The best means to prevent the spread of HSV-2 is _
The best means to prevent the spread of HSV-2 is consistent condom use
Continued pain after the shingles rash resolves is called _
Continued pain after the shingles rash resolves is called post herpetic neuralgia
Name the HSV-1 infections
Name the VZV diagnoses
Small painless papules with central umbilication describes _
Small painless papules with central umbilication describes molluscum contagiosum
Molluscum contagiosum papules will persist for [duration] but will spontaneously regress over time (no treatment needed)
Molluscum contagiosum papules will persist for 6-9 months but will spontaneously regress over time (no treatment needed)
Molluscum contagiosum is caused by [pathogen]
Molluscum contagiosum is caused by pox virus
* dsDNA virus
On histology, molluscum contagiosum will present with _
On histology, molluscum contagiosum will present with inclusion bodies called Henderson-Paterson bodies
* The virus replicates in the cytoplasm of cells and creates inclusion bodies filled with viral particles
How does this condition spread?
Skin to skin contact with an someone infected with molluscum contagiosum
Verrucae are caused by [virus] which causes the infection of the epidermis in children and immunocompromised adults
Verrucae are caused by HPV which causes the infection of the epidermis in children and immunocompromised adults
* The high risk HPV are 16, 18, 31, 33
E6 is an oncoprotein carried by HPV that [action]
E6 is an oncoprotein carried by HPV that inhibits p53
E7 is an oncoprotein carried by HPV that [action]
E7 is an oncoprotein carried by HPV that inhibits retinoblastoma
Histology of verrucae may reveal _ hyperplasia, hyperkeratosis, and [special cells]
Histology of verrucae may reveal epidermal hyperplasia, hyperkeratosis, and koilocytes
_ is the “common wart” that presents with a cauliflower texture most commonly on the hands
Verruca vulgaris is the “common wart” that presents with a cauliflower texture most commonly on the hands
Verruca vulgaris is caused by [HPV subtypes]
Verruca vulgaris is caused by HPV 2 and 4
Verruca plana are found on the [regions]
Verruca plana are found on the mouth and forehead
* These are flat warts
Verruca plana are caused by [HPV subtypes]
Verruca plana are caused by HPV 3 and 10
Warts that are found on the high pressure areas on sole of feet are called _
Warts that are found on the high pressure areas on sole of feet are called verruca plantaris
* Aka plantar warts
Plantar warts are caused by [HPV subtype]
Plantar warts are caused by HPV 1
Condylomata acuminata are sexually transmitted and caused by [HPV subtypes]
Condylomata acuminata are sexually transmitted and caused by HPV 6, 11
White plaques on the tongue that cannot be scraped off are suggestive of [diagnosis] which is mediated by [pathogens]
White plaques on the tongue that cannot be scraped off are suggestive of hairy leukoplakia which is mediated by EBV or HPV
* Squamous hyperplasia of oral mucosa
* Common in HIV patients
White plaques on the back of the tongue are more likely to be _ while white plaques on the lateral aspects are more likely to be _
White plaques on the back of the tongue are more likely to be thrush (candida) while white plaques on the lateral aspects are more likely to be hairy leukoplakia
Candida esophagitis occurs in HIV patients with [CD4 count]
Candida esophagitis occurs in HIV patients with CD4 < 100
At 20-25C, candida is in its _ form
At 20-25C, candida is in its pseudohyphae and budding yeast form
At 37C, candida is in its _ form
At 37C, candida is in its germ tube form
Treat oral candidiasis with _
vaginal candidiasis with _
esophageal candidiasis with _
Treat oral candidiasis with nystatin rinse
vaginal candidiasis with topical azole
esophageal candidiasis with IV fluconazole
[Immune cells] are important for fending off a mucocutaneous candidiasis infection
T cells are important for fending off a mucocutaneous candidiasis infection
* Therefore HIV patients are prone to mucocutaneous candidiasis due to T cell destruction
Candida albicans infection of the epidermis between the skin folds is called _ and should be treated with _
Candida albicans infection of the epidermis between the skin folds is called candidal intertrigo and should be treated with topical nystatin
* Skin folds and high moisture areas, common in obese, diabetic, immunocompromised
What does tinea corporis look like?
Tinea corporis is erythematous, raised, pruritic with central clearing
* There are sharp borders, no satellite lesions
Tinea corporis is caused by [pathogen]
Tinea corporis is caused by dermatophytes
* Trichophyton and microsporum
Tinea corporis can be diagnosed by _ where microscopy shows _
Tinea corporis can be diagnosed by KOH prep where microscopy shows segmented hyphae
Tinea corporis usually occurs in the context of _ ; therefore first choice in management is often _
Tinea corporis usually occurs in the context of high heat/moisture exposure ; therefore first choice in management is often better hygiene practices
* Also use topical azole or terbinafine
Tinea capitis often presents as itchy scalp, hair loss, and [systemic sign]
Tinea capitis often presents as itchy scalp, hair loss, and cervical lymphadenopathy
* Breakage of the hair
The dermatophyte that tends to affect the outer hair shaft (tinea capitis) is _
The dermatophyte that tends to affect the outer hair shaft (tinea capitis) is microsporum
* Ectothrix
The dermatophyte that tends to affect the inner hair shaft (tinea capitis) is _
The dermatophyte that tends to affect the inner hair shaft (tinea capitis) is trichophyton
* Endothrix
Tinea capitis is treated with [topical] or [oral medications]
Tinea capitis is treated with antifungal shampoo or oral griseofulvin
Itching, burning, scaling skin; diagnosis?
Tinea pedis
* Treat with topical azole or topical terbinafine
_ is a superficial fungal skin infection of the nail
Onychomycosis is a superficial fungal skin infection of the nail
* Treat with oral antifungal like terbinafine
Tinea versicolor is caused by [pathogen]
Tinea versicolor is caused by malassezia fungal species
KOH prep of tinea versicolor will reveal _
KOH prep of tinea versicolor will reveal spaghetti and meatball multiple branching hyphae and budding cells
Malassezia causes the degradation of _ which in turn produces _ which is damaging to [enzyme], leading to decreased pigmentation
Malassezia causes the degradation of lipids which in turn produces acid which is damaging to tyrosinase, leading to decreased pigmentation
Tinea versicolor is treated with _
Tinea versicolor is treated with selenium sulfide (topical shampoo)
[Tinea versicolor/ vitiligo] loves the face, neck, abdomen, while [tinea versicolor/ vitiligo] loves the extremities
Tinea versicolor loves the face, neck, abdomen, while vitiligo loves the extremities
Red painful papules and ulcers with pus, ascending lymphangitis is caused by [pathogen]
Red painful papules and ulcers with pus, ascending lymphangitis is caused by sporothrix schenckii
* Lives on vegetation; called rose gardener’s disease
“Cigar shaped fungus” =
“Cigar shaped fungus” = sporothricosis
Sporotrichosis is treated by _ or _
Sporotrichosis is treated by itraconazole or potassium iodide
Necrosis of the nares and palate, black eschar, and air-fluid levels with bony destruction on CT describe [infection]
Necrosis of the nares and palate, black eschar, and air-fluid levels with bony destruction on CT describe mucormycosis
Mucormycosis will present as [microbiology]
Mucormycosis will present as non-septate hyphae with wide angle branching (90 degree)
* Caused by mucor and rhizopus species
Mucormycosis is most common in [population]
Mucormycosis is most common in diabetics in DKA!
Mucormycosis must be treated with _ and _
Mucormycosis must be treated with amphotericin B and surgical debridement
Name the disease process
Pemphigus vulgaris
Name the disease process
Bullous pemphigoid
Name the disease process
Dermatitis Herpetiformis
[Flaccid bullae/ tense bullae] is classic in pemphigus vulgaris
Flaccid bullae is classic in pemphigus vulgaris
* Affects the desmosomes, more superficial
Pemphigus vulgaris is nikolsky sign _ and [does/ does not] have oral mucosal involvement
Pemphigus vulgaris is nikolsky sign positive and does have oral mucosal involvement
Histology of pemphigus vulgaris will show _
Histology of pemphigus vulgaris will show acantholysis, tombstoning, retigular IgG
* Attacks desmoglein 1 + 3
Tense bullae, nikolsky sign negative, linear IgG + C3 deposition describes _
Tense bullae, nikolsky sign negative, linear IgG + C3 deposition describes bullous pemphigoid
* No mucosal involvement
* Lysis between BM and epidermis (goes after hemidesmosomes)
Dermatitis herpetiformis usually affects [population]
Dermatitis herpetiformis usually affects celiacs (tissue transglutaminase)
* HLA-DQ2, HLA-DQ8
Name some clinical features of dermatitis herpetiformis
Name some clinical features of dermatitis herpetiformis:
* Pruritic papules, vesicles, bullae
* Dorsal hands, knees, elbows, buttocks
Which skin region is affected in dermatitis herpetiformis?
Dermis!
* Subepidermal inflammation
* Neutrophilic papillary microabscesses
* Granular IgA in dermal papillae
Erythema multiforme is a reactive skin response involving target lesions with a “dusky” center; commonly associated with _ or _ infection
Erythema multiforme is a reactive skin response involving target lesions with a “dusky” center; commonly associated with HSV-1 or mycoplasma pneumoniae infection
Erythema multiforme can be caused by drugs, including _ , _ , _
Erythema multiforme can be caused by drugs, including sulfas , beta-lactams , mycoplasma pneumoniae
Erythema nodosum is caused by inflammation of the _
Erythema nodosum is caused by inflammation of the subcutaneous fat
* Coccidiodomycosis, histoplasmosis, strep, leprosy, TB, sarcoidosis, IBD
Erythema migrans is associated with [category infections]
Erythema migrans is associated with tic infections
A good way to distinguish SJS from erythema multiforme is _
A good way to distinguish SJS from erythema multiforme is oral mucosal involvement
Bullae and skin peeling, nikolsky sign positive following drug exposure describes _
Bullae and skin peeling, nikolsky sign positive following drug exposure describes steven johnson syndrome (SJS)
Once SJS affects greater than 30% of the body surface area it is classified as _
Once SJS affects greater than 30% of the body surface area it is classified as toxic epidermal necrolysis (TEN)
Common drugs that cause SJS include…
Common drugs that cause SJS include…
* Lamotrigine
* Sulfas
* Penicillins
* Even mycoplasma pneumoniae infection
We treat SJS with _
We treat SJS with steroids
DRESS syndrome stands for _
DRESS syndrome stands for Drug Reaction with Eosinophilia and Systemic Symptoms
How does DRESS syndrome present?
Delayed hypersensitivity reaction involving morbilliform rash and fever after taking certain medications or following herpes viruses
The medications usually responsible for DRESS syndrome are remembered by _
The medications usually responsible for DRESS syndrome are remembered by ABCs
* Allopurinol
* AntiBiotics
* AntiConvulsants
* Sulfas
Transient pink, pruritic, raised, well-circumscribed wheals describe _ ; caused by [hypersensitivity reaction]
Transient pink, pruritic, raised, well-circumscribed wheals describe urticaria ; caused by type 1 HSR
* IgE mediate mast cell degranulation
* Involves superficial dermis spongiosis
Allergic contact dermatitis is classically a [type HSR]
Allergic contact dermatitis is classically a type IV HSR
* Langerhan cells –> T cells –> IFN-gamma
* Increased vascular permeability –> dermal and epidermal spongiosis –> desmosomal compromise
Describe the skin lesions caused by atopic dermatitis
Atopic dermatitis causes erythematous and pruritic weeping papules/ plaques
* The itch that rashes
Babies tend to have atopic dermatitis on [body regions] while adults have it on [regions]
Babies tend to have atopic dermatitis on face, scalp, torso, extensor surfaces while adults have it on flexor surfaces
Atopic dermatitis is a [T helper] response mediated by [cytokines]
Atopic dermatitis is a Th2 response mediated by IL-4 and IL-13
* Involves increase in serum IgE
* Mast cells and eosinophils involved
Mutations in _ gene may be involved in atopic dermatitis
Mutations in filaggrin gene may be involved in atopic dermatitis
Acne vulgaris involves the blockage of a pilosebaceous unit, called a _
Acne vulgaris involves the blockage of a pilosebaceous unit, called a comedone
* Also involves increased sebum production and poor keratinocyte desquamation (not shedding properly)
_ mediates the pro-inflammatory fatty acid production involved in acne vulgaris
C. acnes mediates the pro-inflammatory fatty acid production involved in acne vulgaris
* Sometimes patients are given a short course of doxy to kill bacteria
Hyperandrogenic states such as _ can lead to acne vulgaris
Hyperandrogenic states such as PCOS, anabolic steroids can lead to acne vulgaris
Painful draining sinus tracts with scarring describes [condition]
Painful draining sinus tracts with scarring describes hidradenitis suppurativa
Hidradenitis suppurativa is caused by occlusion of the _
Hidradenitis suppurativa is caused by occlusion of the apocrine glands
* Hormonal stimulation can lead to keratinocyte overgrowth causing occlusion
Hidradenitis suppurativa affects [body regions]
Hidradenitis suppurativa affects axilla, medial thighs, anogenital region
* Painful, draining pustules and cysts
* Eventually scarring and fibrosis
Risk factors of hidradenitis suppurativa include:
Risk factors of hidradenitis suppurativa include:
* Female
* Obesity
* AA
* FH
* Smoking
* Tight clothing
Painful erythematous pustules that arise after hot tub use or aquatic environment describes _
Painful erythematous pustules that arise after hot tub use or aquatic environment describes folliculitis
Folliculitis is most commonly caused by _ or _
Folliculitis is most commonly caused by staph aureus or pseudomonas
Folliculitis is usually self limited, however can progress to _ or _
Folliculitis is usually self limited, however can progress to abscess or cellulitis
Diagnosis?
Folliculitis
Diagnosis?
Pseudofolliculitis barbae
Pseudofolliculitis barbae is most common in [population] following [action]
Pseudofolliculitis barbae is most common in Black males following shaving
The pathophysiology behind pseudofolliculitis barbae is _
The pathophysiology behind pseudofolliculitis barbae is coiled hair shaft trapped beneath the skin –> local inflammation –> firm, hyperpigmented papules and pustules + erythema, pain, pruritis
Rosacea [does/ does not involve] comedones
Rosacea does not involve comedones
* Will see erythematous papules and pustules
* Flushing occurs in response to triggers
Name some common triggers of rosacea
- Heat
- Spicy foods
- Alcohol
- Stress
- Nicotine
_ involves plaques and papules related to hypergranulosis in regions of trauma commonly secondary to chronic Hepatitis C
Lichen planus involves plaques and papules related to hypergranulosis in regions of trauma commonly secondary to chronic Hepatitis C
* Also associated with vitiligo and ulcerative colitis
To remember the presentation of lichen planus, remember the _
To remember the presentation of lichen planus, remember the 6 P’s
* Pruritis
* Pink/Purple
* Planar
* Polygonal
* Papules
* Plaques
Common sites of involvement of lichen planus include the:
Common sites of involvement of lichen planus include the:
* Shins
* Ankles
* Wrists
* Genitalia
Often follows lines of minor trauma (Koebner phenomenon)
Oral mucosal involvement of lichen planus is called _
Oral mucosal involvement of lichen planus is called wickham striae
Lichen planus is [immune cell]- mediated and affects the [skin layer]
Lichen planus is T-cell (CD8+)- mediated and affects the dermal-epidermal junction (interface dermatitis)
* Histology shows hypergranulosis
* Saw tooth rete ridges
* Lymphocytic infiltrate
Rash with a christmas tree distribution =
Rash with a christmas tree distribution = pityriasis rosea
* Red/pink plaques with collarette scale
Pityriasis rosea often presents in [population] after _
Pityriasis rosea often presents in children or young adults after viral infection
* It can also be idiopathic
* But often there is a prodrome + herald patch (URI, fever)
Psoriasis is ultimately caused by _
Psoriasis is ultimately caused by overactivity of the stratum basale –> increasing keratinocytes
* Result of inflammatory state (TNF-alpha, IL-6, CRP, HLA B27)
Erythematous raised papules and plaques with a silvery scale on the extensor surfaces and scalp describes _
Erythematous raised papules and plaques with a silvery scale on the extensor surfaces and scalp describes psoriasis
Pin-point bleeding when picking at psoriasis scales is _ sign
Pin-point bleeding when picking at psoriasis scales is Auspitz sign
When a patient presents with psoriasis, check for other involvement of the _ and _
When a patient presents with psoriasis, check for other involvement of the nail beds (pitting) and joints
Psoriasis will present with [findings] on histology
Psoriasis will present with hyperkeratosis, parakeratosis, acanthosis on histology
* There will be thickening of the stratum spinosum, decreased stratum granulosum
[Benign skin lesion] is a precursor to squamous cell carcinoma
Actinic keratosis is a precursor to squamous cell carcinoma
* Presents as sandpaper white scale –> erythematous or brown papules
* Pre-cancerous; increased dysplasia increases SCC risk
Risk factors of actinic keratosis include _ and _
Risk factors of actinic keratosis include sun exposure and age
Actinic keratosis on histology reveals _
Actinic keratosis on histology reveals parakeratosis and hyperkeratosis
* Manage with freezing, topical 5-FU, or surgical excision
Squamous cell carcinoma usually presents on the face, ears, hands, and [upper/ lower lip]
Squamous cell carcinoma usually presents on the face, ears, hands, and lower lip
Squamous cell carcinoma risk factors include:
Squamous cell carcinoma risk factors include:
* Sun exposure
* Age
* Immunosuppression
* Chronic wounds
* Burns
* Arsenic
[SCC/ BCC] bleeds easily and is nonhealing
Squamous cell carcinoma bleeds easily and is nonhealing; it is painless
* Locally invasive, remove with surgical excision
Squamous cell carcinoma will show _ on histology
Squamous cell carcinoma will show onion skin keratin pearls on histology
* Additionally atypical nuclei
Basal cell carcinoma is common on the head, neck, hands, and [upper/ lower lip]
Basal cell carcinoma is common on the head, neck, hands, and upper lip
Basal cell carcinoma will present as _ on biopsy/histology
Basal cell carcinoma will present as palisading nuclei on biopsy/histology
Diagnosis?
Basal cell carcinoma
* Waxy, pink, pearly plaques
* Crusting, ulceration, scaling plaques
* Sometimes telangiectasias
_ is the most common skin cancer
Basal cell carcinoma is the most common skin cancer
_ is a dome shaped, core of keratin
Keratoacanthoma is a dome shaped, core of keratin
* Erythema + scale
* Rapidly growing
* Occur in the middle age and elderly
* May spontaneously regress
Diagnosis?
Keratoacanthoma: rapidly growing dome with a crater in the center of keratin
Diagnoses?
The malignant cells in melanoma are dervied from [embryonic structure]
The malignant cells in melanoma are dervied from neural crest cells
* Recall that the ncc derivatives are MOTEL PASS
* Melanocytes, odontoblasts, tracheal cartilage, enterochromafin like cells, laryngeal cartilage, parafollicular C cells, all ganglia and adrenal medulla, schwann cells, septum (aorticopulmonary)
Name the ABCDEs of melanoma
A- asymmetry
B- border
C- color
D- diameter (> 6 mm)
E- evolution
Name some risk factors for melanoma
Name some risk factors for melanoma:
* Family history
* Light skin
* Sun exposure
* Sunburn
* Dysplastic nevi
* Immunosuppression
* Genetics
Name the skin layer involved in melanoma: _
Name the skin layer involved in melanoma: stratum basale
Name (4) subtypes of melanoma
Name (4) subtypes of melanoma
1. Superficial spreading
2. Lentigo maligna
3. Nodular
4. Acral lentiginous
The most common subtype of melanoma is _
The most common subtype of melanoma is superficial spreading
_ is a melanoma subtype that has a long radial phase
Lentigo maligna is a melanoma subtype that has a long radial phase
* Spreads left to right (superficial)
_ melanoma has no radial phase and instead has deep penetration early
Nodular melanoma has no radial phase and instead has deep penetration early
_ melanoma has no relation to sun exposure and happens on dark skins on the palms and soles and under the fingernails
Acral lentiginous melanoma has no relation to sun exposure and happens on dark skins on the palms and soles and under the fingernails
_ is a genetic marker of neural crest cells which is positive in melanoma
S-100 is a genetic marker of neural crest cells which is positive in melanoma
_ mutations are common in melanoma; they allow uncontrolled cell proliferation; _ mutations affect a tumor suppressor
BRAF mutations are common in melanoma; they allow uncontrolled cell proliferation; CDKN2A mutations affect a tumor suppressor
Metastasis of melanoma is common to the _
Metastasis of melanoma is common to the lymph nodes, brain, bone, heart
The most important prognostic factor with melanoma is _
The most important prognostic factor with melanoma is depth of invasion/ Breslow thickness
Treatment of melanoma first begins with [biopsy] followed by [medication options]
Treatment of melanoma first begins with excisional biopsy with wide margins followed by BRAF inhibitors (vemurafenib), IL-2 (aldesleukin) or IFN-alpha
Describe the burn classification
_ are benign “red moles” that occur with old age
Cherry hemangiomas are benign “red moles” that occur with old age
_ are benign vascular tumors that occur in the first weeks of life and disappear at 5-8 years
Strawberry hemangiomas are benign vascular tumors that occur in the first weeks of life and disappear at 5-8 years
Bacillary angiomatosis must be treated with _
Bacillary angiomatosis must be treated with doxycycline
* Macrolides can be used for cat scratch fever but not strong enough for angiomatosis
Bacillary angiomatosis is associated with a _ infiltrate, while Kaposi sarcoma has a _ infiltrate
Bacillary angiomatosis is associated with a neutrophilic infiltrate, while Kaposi sarcoma has a lymphocytic infiltrate
Kaposi sarcoma is more common in [population] and it is caused by [infection]
Kaposi sarcoma is more common in eastern european males and it is caused by HHV-8
“Stuck on” appearance =
“Stuck on” appearance = seborrheic keratosis
* Benign hyperpigmented plaque/papule
* Common in increasing age
* Greasy appearance
The sudden appearance of multiple seborrheic keratosis lesions is a sign of possible _
The sudden appearance of multiple seborrheic keratosis lesions is a sign of possible GI adenocarcinoma
* Leser-Trelat sign
The mechanical barrier of the skin that regulates water loss:
The mechanical barrier of the skin that regulates water loss: stratum corneum
The mitotically active keratinocytes are found here:
The mitotically active keratinocytes are found here: stratum basale
* Think of melanoma in this layer
Intercellular junctions of the epidermis; think this layer:
Intercellular junctions of the epidermis; think this layer: stratum spinosum
Formation of the cornified cell envelop occurs in this layer:
Formation of the cornified cell envelop occurs in this layer: stratum granulosum
* Keratohyalin granules also found here
Melanocytes are found in the [layer]
Melanocytes are found in the basal layer of the epidermis
Abnormal premature keratinization is called _ ; squamous cell carcinoma is an example
Abnormal premature keratinization is called dyskeratosis ; squamous cell carcinoma is an example
Hand-foot-mouth disease is caused by [pathogen]
Hand-foot-mouth disease is caused by coxsackie or other enteroviruses
* Erythematous macules on the palms, soles, mouth vesicles
* Treatment is supportive
Erythema infectiosum is caused by [pathogen]
Erythema infectiosum is caused by parvovirus
* Slapped cheek
Parvovirus is a [type virus] that is spread by respiratory secretions and common in school aged kids; can cause hydrops fetalis in pregnancy
Parvovirus is a ssDNA virus that is spread by respiratory secretions and common in school aged kids; can cause hydrops fetalis in pregnancy
What is the timeline of the parvo B19 infection?
- Flu like symptoms
- 7-10 days later erythematous malar rash (slapped cheek)
- Few days after, diffuse reticular, lacy rash
A prodrome of a very high fever in a young child followed by diffuse macular to maculopapular rash after the fever resolves describes _ ; caused by [pathogen]
A prodrome of a very high fever in a young child followed by diffuse macular to maculopapular rash after the fever resolves describes Roseola ; caused by HHV6 & HHV7
A prodrome of fever, arthralgias, malaise followed by a herald patch and later multiple papules and plaques is most often caused by [pathogen]
A prodrome of fever, arthralgias, malaise followed by a herald patch and later multiple papules and plaques is most often caused by HHV6 or HHV7
Itching and small papules in the webspaces likely describes _
Itching and small papules in the webspaces likely describes scabies
* Sarcoptes scabiei
The pruritis mechanism for ectoparasites is _ mediated
The pruritis mechanism for ectoparasites is IgE mediated
Diagnosis?
Pityriasis versicolor
* Recall that it can be hyper or hypopigmented
Tinea pedis is most commonly caused by [specific dermatophyte]
Tinea pedis is most commonly caused by trichophyton
Erythema with overylying greasy yellow scale in the scalp, ears, eyebros, nasolabial folds, central chest, etc describes _
Erythema with overylying greasy yellow scale in the scalp, ears, eyebros, nasolabial folds, central chest, etc describes seborrheic dermatitis
* Think dandruff
* Common in areas of high sebum production
* Can cause post-inflammatory hypopigmentation
Seborrheic dermatitis is due to an inflammatory response to [pathogen]
Seborrheic dermatitis is due to an inflammatory response to Malassezia
* Treat with ketoconazole cream
What cell type mediates allergic contact dermatitis?
Th1
