MIDTERM Flashcards
How many days does it take to form EPIDERMIS
28 days
What two layers form the DERMIS
Where do Meissners and Pacinian Corpuscles belong?
Papillary Layer = thin upper (Meissners)
Reticular = THICK lower (Pacinian)
Name the three phases of hair growth
Anagen = growth phase (2-6yrs)
Catagen = transition (2-3 weeks)
Telogen = resting (3mo)
What phae is hair colored in?
Anagen Phase = growth phase
EUMELANIN=
black/brown hair
Pheomelanin
BLONDE
Erythromelanin
RED
Longitudinal band of brown/black pigment stretching from matrix to nail folds
MELANONYCHIA
Hutchinson’s sign
small, discrete erythematous scaling papules on the trunk and extremities, some of which coalesce
GLUTTATE PSORIASIS
irregular and asymmetric hyperpigmented patch with striking variegation of pigmentation
MELANOMA
Primary Skin Lesions
: flat, < 1 cm
: flat >1 cm
Macule: flat, < 1 cm
Patch: flat >1 cm
Primary Skin Lesions
: Elevated < 1 cm
: Elevated > 1 cm
Papule: Elevated < 1 cm
Plaque: Elevated > 1 cm
Primary Skin Lesions
: Large palpable mass > 1 cm
: Fixed large nodule > 2 cm
Nodule: Large palpable mass > 1 cm
Tumor: Fixed large nodule > 2 cm
Secondary Skin Lesions
Do erosions scar?
Loss of epidermis
heals WITHOUT scarring
Secondary Skin lesion
Loss of tissue leading to exposure of dermis/ fat
Does it scar?
ULCER
heals with scarring
red macule due to vasodilation
blanches under pressure ( essentially vasoconstricting
it so redness stops )
ERYTHEMA
Extravasation of RBCs
* does not blanch under pressure ( RBCs are out so pressing won’t make a difference )
PURPURA
Dilated vessel i.e. spider angiomas
Telangiectasia
Thickening of stratum corneum d/t to keratinocyte proliferation
Lichenification
Yellow Red papule from fat deposition
XANTHOMA
Itchy, evanescent Hypopigmented papule/plaque d/t edema
from dermis associated with allergies
WHEAL
What is a good screening tool for susceptibility to skin cancer?
Fitzpatrick Skin Types
What happens after 15 min of sun exposure w/o sunscreen
Always -> never
Fitzpatrick Skin Types
Type I: Always burn, never tan
Type II: Usually burns, sometimes tans Type III: Sometimes burns
Type IV: Rarely burns
Type V: Very rarely burns
Type VI: Never burns, always tans
(Always Burns –> Never Burns)
(Never Tan –> Always Tan)
dead, protective layer of epidermis
Stratum corneum
layer of epidermis present in thick skin dead cells
Stratum lucidum
Are there blood vessels in the epidermis?
NO
merocrine, tubular glands that help with thermoregulation
SWEAT GLANDS
* Eccrine – found everywhere
* Apocrine – found in axila, pubic, perianal area
HOLOCRINE, associated with hair follices, nerve endings, smooth muscle
SEBACEOUS Glands
transepidermal water loss → Ca2+ gradient loss →
lamellar body ( lipid-containing) secretion → cytokine secretion, inflammation and keratinocyte proliferation
What are the two barriers to UV radiation?
Melanin and Protein Lipid Barrier in the stratum corneum
defects in lipid metabolism or the protein components of the stratum corneum are accompained by skin barrier defects
ICHTHYOSIS
Acute and Chronic eczema result in vesicular lesions that lead to ulcerations and erosions that become easily colonized and infected
Eczema with spongiosis
desquamative inflammatory dermatoses make the skin barrier function less effective
lymphocytic infiltrate with vasculitis
URTICARIA
bacterial infection
ulceration and acute inflammation
IMPETIGO
In desquamative, inflammatory dematosis, is the skin barrier intact and fully functional?
NO
What dermatological condition demonstrates HORNCYSTS?
Seborrheic keratosis
What dermatological condition results from bacterial infection?
IMPETIGO
If munroe’s microabscess is seen on a pathologiclal specimen slide, what dematological condition is present?
PSORIASIS
vitiligo, tinea, moles, freckles, sunspots, lentigenes are examples of
Macules and Patches
Acne, boils, candida, chickenpox, impetigo are examples of
PUSTULES
Small patch of BULGING skin filled with PUS
nodule with a central punctum
cheesy, yellow, keratin material
lined by flat epidermal cells, has a granular layer surrounding keratin
Epidermal Inclusion Cysts
rapid build up of epidermal cells especially over the knees and elbows
SILVERY SCALING
Histopath: Parakeratosis = cell nuclei within stratum corneum
THERE IS NO GRANULAR LAYER
CD8 is in the DERMIS / CD4 is in EPIDERMIS
PSORIASIS
Thick skin, increased keratin (stratum corneum) layer
Plantar (SOLES of Feet)
VITAMIN DEFICIENCIES (E, A, D)
Hyperkeratosis
benign neoplasms of melanocytes
grows as nests of melanocytes at the dermal-epidermal junction can extend into dermis
FLAT macule or RAISED Papule, usually < 6mm
NEVI
Dysplastic nevus is a precursor
MELANOMA
Antibodies against desmogelin 3 is seen in what bullous disease?
Pemphigus Vulgaris
Antibodies against hemidesmosmes is seen in which bullous disease?
Bullous phemphigod
If Nikolsky’s sign is positive, what bulloys disease?
Pemphigus Vulgaris
Pemphigus Vulgaris vs Bullous Phemphigoid Immunofluorescence appearance
Pemphigus Vulgaris – FISH NET
Bullous Phemigoid – LINEAR PATTERN
Autoimmune bullous disease of IgA at the tips of dermal papillae
Consists of: pruritic vesicles and bullae grouped together bullae-> filled with watery fluid, PMN’s, and eosinophils
Dermatitis Herpetiformis
What skin disease is associated with celiac disease and resolves with a gluten free diet?
Immunofluorescence: granular deposits w/in the dermal papillae
Dermatis Herpetiformis
multisystem blood vessel diseaes
* Affects: mostly men in the 4th and 5th decade of life
* Associated with Hep B in some patients
* Skin: may show gangrene, nodules purpura, rashes, ulcers, livedo reticularis
Most often on legs
Polyarteritis Nodosa Vasculitis
Hypersensitivity reaction of dermal blood vessels
* Characterized by: targeted rash and bullae of skin and mucous membranes
* Associated with herpes simplex, penicillin, SLE, steven johnson syndrome
vascular interface dermatitis w lymphocytes along dermo epiderm junction
Erythema Multiforme
What are Nevi, can they extend into the dermis?
Benign neoplasms of melanocytes
YES
What is acantholysis?
Seen in pemphigus vulgaris, seperation of the stratum spinosum keratinocytes. BM is connected, Nikolsky’s sign happen on skin and oral mucosae
What is the antibody formed in bullous pemphigod?
In celiac disease, what is the immunoglobulin?
It is also used diagnostic immunofloruensce
Anti-hemidesmosomes
IgA
Which has a histopathology that demonstrates vaculoar interface dermatitis with lymphocytes along the dermo epidermal junction?
erythema multiforme
What vasculitis shows rashes, ulcers, subQ nodules and livido reticularis?
It is likely in a 40 yo male with Heb B
PAN
Polyarteritis Nodosa
Patient presents with oral lesions and blisters that easily rupture. Immunofluorescence depicted with image on left. What does this patient most likely have?
Pemphigus vulgaris
immunofluorescence = FISH NET
A 45 year old patient presents with red lesions on the lower legs shown in picture. He also has a fever and endorses night sweats. What is this condition associated with in some patients?
HEP B
Polyartertis Nodosa Vasculitis
What Fitzpatrick Skin Type is the following person: usually burns, sometimes tans?
Type II
What are the four infection sites of Strep pyogenes and what do we see
Corneum – IMPETIGO
Epidermis – Ecthyma
Dermis – Erysipelas
Cellulitis – FAT
Patient comes in with painless, prurutic vesicular rash. When the fluid dries it forms a honey colored thick crust. What do you suspect?
IMPETIGO
What protein inhibits osponization and phagocytosis seen in strep impetigo?
M PROTEIN
Patient presents with “fiery red patch” rash you suspect ERYSIPELAS. What is a predisposing factor to this?
LYMPH OBSTRUCTION
Bacterial cause of cellulitis, infects skin abrasions upon contact with contaminated raw meat and fish
Erysipelothrix rhusiopathiae
What Induces pro-inflammatory cytokine production and Activates endothelia (rash and inflammation)
Streptococcal Pyrogenic Exotoxin B (SpeB)
What toxins damage mammalian cells, resulting in cell lysis and release of lysosomal enzymes
Streptolysin O and S
Two mechanisms involved in Necrotizing Fasciitis
Streptodornases and Hyaluronidase
Newborn presents as febrile, erythematous lesions around mouth, nose and neck. + Nikolsky sign
Staph Scalded Skin Syndrome
What toxin is involved in Staph Scalded Skin Syndrome
Exfoliative Toxin A and B
What staphylococcus virulence factors are responsible for folliculitis, furnucles and carbuncles?
Adhesins/Teichoic Acid
Capsules and Protein A
Toxins
Another major cause of folliculitis: grows in adequately chlorinated warm water (hot tubs)
Pseudomonas Aeruginosa
Another major cause of folliculitis: itchy acne-like eruption on the upper back, upper arms, chest, neck, chin and face
Malassezia furfur
How does VZV infect the skin epithelia when it is in the Lymph node?
VIREMIA to liver ans spleen via T cells and monocytes –> skin –> local nerve
What virulence factor is responsible for viral dissemintation of varicella zoster virus?
VZV glycoprotein C
binds to chemokine and then to chemokine receptor triggering enhanced recruitment and migratory action of monocytes, dendritic
cells, and T cells
Name the VIRUS
ssDNA naked virus
Transmission = inhalation of contaminated resp dropplets
Patients no longer contagious once the rash has appeared – due to immune response
PARVOVIRUS B19
Child presents to urgent care with cold like sympotoms, fever, headache and facial rash
Rash develops a lacy, reticular pattern
FIFTH DISEASE
erythema infectiosum
Which type of hypersensitivity reaction is seen in Fifth disease?
Parvovirus B19
Type 3
What virus and what disease?
Patient presents with blister-like painful lesions in the mouth (herpangina) & skin rash
Oral and pharyngeal ulcers and vesicular rash of palms of hands + soles of feet
Coxsackievirus
Hand Foot Mouth Disease
Patient presents with fever, cough, coryza, conjunctivitis, koplik spots, rash, diffuse blotchy erythematous maculopapular rash
Leukopenia and Serum Vit. A is DEC
Vaccine: MMR
MEASLES (RUBEOLA)
complication = subacute sclerosing panencephalitis
Patient presents with Postauricular/occipital lymphadenopathy ( usually before rash)
Forschheimer spots on mucosa (pinpoint, red/purpule macules on uvula)
If congenital – Blueberry Muffin Rash + sensorineural deafness/cataract
Rubella GERMAN MEASLES
patient presents with vesicles that look like dew drops on a rose petal
Vesicular rash in crops
Giant cells on Tzanck Smear
Varicella (Chickenpox)
reactivation as shingles
Patient has a high fever for 3-5 days and then rash breaks out once fever subsides
non-pruritic blanching erythematous maculopapular rash starts on trunk –> spreads to out to face and extremities
Roseola Infantum
HHV 6
Little 6 yo Rosy has a Rash
complication - seizures
Patient presents with skin colored pearly papules with central umbilication
Molluscum bodies (keratinocytes + eosinophilic cytoplasmic inclusion bodies)
Molluscum contagiousm
Kissing Disease
Fatigue * distinct in children* , exudative pharyngitis, lymphadenopathy ( posterior cervical ) , hepatosplenomegaly,
Infectious Mononucleosis
EBV (HHV4)
Patient presents with clustered vesicles on an erythematous base and eroded bullae that can leave scars
“Cold sore”/”Fever blister”
** Multinucleated Giant cells on Tzanck smear**
HSV
Vesicular/ulcerative rash around the mouth
Could also present with herpetic whitlow ( vesicular lesions )
Herpetic Gingivostomatitis
Round papules with rough edges ( warts ) that can occur anywhere, often hands
HPV 2 and 4
Verruca Vulgaris
Condyloma Acuminata (HPV 6/11) – genital warts
This infection is seen in contact lens wearers – dont wash with tap water
Chronic Granulomatous Dermatitis
Acanthamoeba Infection
Infection caused by sandfly bite
Visceral:
Mucocutaneous
DERMAL: hypopigmented macules –> diffuse nodular lesions
Leishmaniasis
infection due to skin penetration by freshwater snails causing dematitis
Swimmer’s Itch
Katayama Fever, Pruritic Rash
Schistosmiasis
Infection die to larvae from soil penetrates human skin –> serpiginous tunnel
Ground Itch
Ancylostomiasis
Mosquito vector transmits tiny larvae with bite in human
Adult worm may form in subcutaneous nodules and subconjunctival nodules
Dirofilariasis
infection due to drinking contaminated water (water flea = cyclops)
Worm migrates to skin – blisters on legs and feet
Dracunculosis
infection due to bite of black fly (simulium) on subcutaneous tissue forming painless skin nodules affecting eyes
Dermatitis and Keratoconjunctivitis – river blindness
Onchocerciasis
infection via bite from Mango Fly (Chrysops) –> eye –> subconjunctivia
Calabar Swelling of eye
Loiasis
Loa Loa = filarial nematode
infection due to ingestion of undercooked pork – enters mucosa of intestines (striated muscle, heart, brain)
Myalgia
Tx: Albendazole
Trichinellosis
Human Lice infestation
Pediculosis
Pediculosis ciliaris ->conjunctivitis -keratitis
Complication - impetigo
skin infection caused by fly larvae (maggots) of dermatobia hominis (human bot fly)
Furnucular , Wound and Migratory depending on species
MYIASIS
Chiggers – Scrub itch
agent = harvest mite – bite thin areas of skin
severly prutitic papules or vesicles
Trombidiosis
What is the causative agent?
Patient presents with a visibly lumpy jaw; oral/fascial abscesses that that drain through sinus tracts with yellow sulfur granules
Ac+inomyces israelli
Bacterial Infection
What is the causative agent
Pt. said they were scratched by a cat and now presents with bacillary angiomatosis
Tx: Erythromycin or Doxyclcline
BartoNellosis
What is the causative agent?
Pt. is a butcher recently handling contaminated raw fish and meat. Presents with violaceous lesions with raised margins b.w fingers and spares
TX: Penicillin
ERYSIPELOID
(Erysipelothrix rhusiopathiae)
What disease?
Patient was recently in contact with infected horses, now has ulcerated nodule with regional lymphadenopathy
GLANDERS
What disease?
Child comes in petechiae on his extremities, which is progressing to ecchymotic
Tx: ICV penicillin or ceftriaxone
Meningococcemia
What disease?
Pt. presents with 1-3 mm pits on plantar surface of feet
Tx: Topical erythromycin, clindamycin, or benozyl peroxide
Pitted Keratolysis
Kytococus Sedentarius
What disease?
Patient presents with erythematous macules or papules and fever. Was possibliy in contact wiith rats and or contaminated food.
Rat bite Fever (Haverhill fever)
Streptobacillus moniliformis
What disease
Patient presents with hypertrophic plaques on nares
Histopath shows MIKULICZ cells
Rhinoscleroma
(Klebsiella pneumoniae)
S. aureus produces what?– which can produce bullous or exfoilative skin lesions?
TSS, Staph. scaled skin syndrome, bullous impetigo, scarlet fever
EXOTOXINS
Enanthem vs. Exathem
Enanthem = rash INSIDE body : strawberry tongue/exudative pharynigitis
Exanthem = diffuse erythematous rash with sandpaper texture that starts on head and neck.spreads, circumoral pallow and pastiass lines
What disease
Patient has yellowish brown concretions on axillary hair shafts
Trichomycosis Axillaris
(Corynebacterium tenuis)
Patient presents with solitary lesion and has no sensory loss
Leprosy
(Mycobacterium leprae)
Pt. comes in with bright pink, painful nodules on UE/LE and face
Type 2 Erythema Nodosum leprosum
Tx = Thalomide
Hematogenous spread of mycobacteria from fulminant tuberculosis of the lung or meninges
exposure to contaminated surgical instruments
Miliary tuberculosis of the skin
Swimming pool
Begins as a small papule at the site of inoculation and evolves into a nodule or granulomatous plaque
Tx: Minocycline
Pool/Aquarium Granuloma
Exposure to humidity, moisture, warmth, and increased CO2 tension
sharply demarcated hyper/hypopigmented macules with slight scaling on neck, shoulders, chest, back, and abdomen
Histo: spaghetti/meatball → turns into hyphae and spore ), + Woods lamp
Pityriasis/tinea versicolor
(Malassezia)
black ,firm, adherent concretions
white, soft, nonadherent small concretion.
Both found on scalp, beard, moustache, and beard areas.
Tinea piedras
arthroconidia invade interior of hair shaft
black dots are remnants of brittle hair broken at the surface of the scalp
Endothrix - Black Dot Ringworm
chronic infection of the scalp - begins during childhood
Yellowish cup shaped crusts made up of hyphae and keratinous debris
FAVUS (t. schoenleinii)
dermatophyte infection of the nails
* AIDS Marker *
Onychomycosis
Tinea Ungium
How do you treat tinea?
With antifungals only NOT systemic steroids
Gardening, farming, being florist ( organism lives in soil )
fixed cutaneous = lesion without lymphatic spread, occurs with prior exposure vs. lymphocutaneous = subcutaneous macules and papules that follow the shape/flow of lymph vessels, ulceration with lymphatic spread usually on hand, forearm, and leg
“Cigar bodies/ asteroid bodies
Sporotrichosis ( from sporothrix schenckii
found in Tropic of Cancer
Penetrating wound in the foot
Presents as : Subcutaneous abscesses
Mycetoma/ madura foot
from soil saprophytes, decaying vegetation / Found in tropics/subtropics
Cauliflower-like tumors that can conjoin, irregular verrucous plaques, annular nodules with central clearing
Histo:“Copper pennies
Chromoblastomycosis/ Verrucous dermatitis
associated with bottlenose dolphins
** Painless keloids**, nodules, ulcers, and verrucous lesions on face and UE
Biopsy: “Chain of coins”/ “brass knuckles”
Lacaziosis/Keloid Blastomycosis/Lobo’s Disease
Exposure to soil with bat, bird, and/or chicken droppings
Cutaneous manifestations in AIDS = general macules, papules, nodules, ulcers, that are molluscum-like
Primary cutaneous ( rare )= chancre with lymphadenopathy
Histoplasmosis/Cave Disease
Symptoms: Acts like virus causing resp disease/ cough/ fever & causes chronic pulmonary symptoms that mimic pneumonia
Gilchrist’s Disease: primary cutaneous manifestation
Blastomycosis ( from Blastomyces dermatitidis
found in Southern California, Arizona, New Mexico, SW Texas
Asymptomatic, self-limited resp infection or pulmonary manifestation with flu-like symptoms
Cutaneous ( rare )= chancre-like lesion with lymphadenitis
Disseminated cocci ( rare ) = papules, pustules, nodules on face, scalp, neck
Coccidioidomycosis/ San Joaquin Valley Fever
from Coccidioides immitis
found in Brazil
Skin symptoms: Papules, vesicles, crusty granulomatous lesions
Biopsy: “Mariner’s Wheel” ( large thick round cells with buddings attached to mother
Paracoccidioidomycosis ( from Paracoccidioides brasiliensis
found in SE Asia
Skin symptoms:** Molloscum-like**, mucocutaneous lesions Biopsy: Intra/extracellular oval/round yeast shaped
Penicilliosis ( from Penicillium marneffei)
encapsulated and found in pigeon droppings
Primary cutaneous = sentinel of disseminated disease ( to the CNS, bone, skin, lungs )
Cutaneous symptoms ( 10-15% of HIV patients )= nodules, papules ulcers, cellulitis, molluscum-like on head, neck ,mouth, and nose
Cryptococcosis ( Cryptococcus neoformans, gatti )
MOST COMMON FUNGAL OPPORTUNISTIC INFECTION
increased risk if impaired epithelial cell barrier, systemic illnesses, catheters, heat, and humidity *
Skin symptoms: Thrush ( tongue ),perleche, vulvovaginitis/balanitis, folliculitis, onychomycosis
Cutaneous: papulonecrotic eschars and purpura
Biopsy: budding yeast with pseudohyphae
Candidiasis ( from Candida albicans
2nd MC cause of opportunistic infection, found in leaves, grain soil
Starts in lungs usually
Cutaneous manifestations = Usually due to trauma; erythematous macules, papules, and plaques → turn into hemorrhagic bullae and ulcerations with central necrotic eschar
Aspergillosis
caused by acholoric algae in stagnant water
Skin symptoms: Papules, plaques, vesicles, cellulitis, eczematoid dermatitis, verrucous nodules. 1⁄3 of cases also causes olecranon bursitis
Protothecosis ( from prototheca wickerhamii )
3 Pathogenesis of ACNE
- Keratinocyte proliferation
- Excessive sebum production
- Cutibacterium acnes
gram positive non motile rod found deep within the sebaceous follicle
CUTIBACTERIUM ACNES
this acne treatment:
normalization of follicular keratinization and corneocyte cohesion which aids in the expulsion and existing comedones and prevents formation of new ones
Have anti-inflammatory properties
RETINOIDS
acne treatment
potent bacteriocidal agent that reduces P. acnes within the follicle
Benzoyl Peroxide
naturally occurring dicarboxylic acid that inhibits protein synthesis of P. acne
- Also aids in reversing the hyperkeratosis or the hair follicles, thus decreasing microcomedo formation
AZELAIC ACID
bacteriostatic agent that inhibits folic acid synthesis by competing with para-aminobenzoic acid
Dapsone
What drug can cause blue pigmentation of teeth and nails?
MINOCYCLINE
analog of Vitamin A; oral therapy effective to induce long-term remission of acne; dosing = 0.5-2 mg BID; should get 120-150 mg/kg over their treatment course
Can cause teratogenicity and toxicity:
Isotretinoin
tumors contains FXIIIa positive dermal dendritic cells
appear at firm tan brown papiles – often flat
Benign Fibrous Histiocytoma = Dermatofibroma
hyperplasia and tendency of fibroblasts to surround collagen bundles
Pathogenesis: Molecular Hallmark
- Translocation: gene encoding for collagen 1A1 (COL1A1) and platelet-derived growth factor-beta (PDGFB)
- Resulting Rearrangement: Juxtaposition of COL1A1 promoter sequences and the coding region of PDGFB
- Overexpression and increased secretion of PDGFB: drives tumor cell growth through autocrine loop
Dermatofibrosarcoma protuberans
Tumor consists of flesh-colored fibrotic nodule on sectioning. Lesions often infiltrates the subcutis in a manner reminiscent of “swiss chess” to adicionades. Characteristic storiform (swirling) alignment of the spindled cells is apparent
Dermatofibrosarcoma protuberans
Intracellular accumulation of cholesterol within macrophages
Foamy cell clusters: subepithelial connective tissue of skin; tendons
Depositions of yellowish cholesterol rich material
Xanthomas
Associated condition: cholestasis
local dilation of a structure vs permanent dilation of preexisting small vessels
Ectasis v. Telangiectasia
spider telan. = arrays of dilated subcut. arteries- blanch w press
Mutation: TGF-beta signaling pathway genes
–> dilated capilaries and veins - present at birth
Hereditary Hemorrhagic Telangiectasia = Osler-Weber-Rendu disease
common tumors
Increased number of normal and abnormal vessels filled with blood
3 types: capillary, juvenile, cavernous
Hemangiomas
Most common type of hemangioma
* made up of thin-walled capillaries with scant stroma
* occur in skin, subcut. tissue, mucous membranes
CAPILLARY Hemangioma
Strawberry type hemangiomas of the newborn
Fade by 1-3 years of age and completely regress by age 7 in most cases
Juvenile Hemangioma
What type of hemangioma
- Rapidly growing red lesion of skin, gingiva, and/or oral mucosa
- Bleed easily and ulcerate
- Develop after trauma
Cavernous Hemangioma – Pyogenic Granulomas
Two types of angiosarcomas
associated with carcinogenic exposure
Malignant Tumor
Organ associated and cutaneous form
This type of angiosarcoma begins as multiple deceptively small nodules that become
asymptomatic red papules
- Color: fleshy masses of red-tan to gray-white tissue
- Margins blur surrounding structures
- Central areas of necrosis and hemorrhage
Cutaneous Angiosarcomas
T cell lymphoma that presents in skin → Lymphoma - Characteristics:
- Erythematous plaques early in disease
- Appear on trunk, extremities, face, and scalp - Size of nodules correlates with spread
Mycosis Fungoides/Sezary Syndrome
Pathology of what disease has Pautrier’s Microabscess
Sezary Syndrome
a group of idiopathic disorders:
Letterer-Siwe disease
Hand Schuller Christian Syndrome
Localized Eosinophilic Granuloma
Langerhans Cell Histiocytosis
this disease occurs before age 2/ocasionally adults
* Cutaneous lesions resembling a seborrheic eruption - infiltrates of LCs; front/back of the trunk, scalp - Hepatosplenomegaly
* Lymphadenopathy
* Pulmonary lesions
Letterer-Siwe disease
(Multifocal Multisystem)
Langerhans Cell Histiocytosis
2nd MC tumor of sun-exposed sites in older people
- Higher incidence in M > F
- Premalignant condition: Actinic keratosis
- Invasive/metastasize
Path: UV induced DNA damage to squamous cells defect in p53/RAS
Squamous Cell Carcinoma
Most common invasive cancer in human
- rarely metastasizes
- Incidence: increase in immunosuppression, increase in xeroderma pigmentosum
Present as pearly papules
Basal Cell Carcinoma
Do basal cell carcinomas occur on mucosal surfaces?
NO – arise from the epidermis or follicular epithelium
pathogenesis of basal cell carcinomas is due to mutations in what?
mutations in p53
What is the morphological progression of melanocytic nevi ?
Junctional –> Compound –> Intradermal
What’s unique about Intradermal Nevi
Undergo maturation = NEUROTIZATION
- Fusiform cells
What type of NEVUS?
- non-nesting/dermal infiltration/fibrosis
- heavily pigmented
CLINCALLY CONFUSED WITH MELANOMA
BLUE NEVUS
What type of NEVUS?
- fascicular growth pattern
- plump and fusiform cells with pink-blue cytoplasm
clinically confused with hemangiomas
SPITZ NEVUS
MRA Drug
MEK inhibitor indicated for melanoma with BRAF mutations
TRAMETINIB
MRA Drug
BRAF protein kinase inhibitor
Dabrafenib
What type of basal cell carcinoma presentation?
flush with skin, erythematous , scaly +/- shallow ulcer or crusting
Superficial Basal Cell Carcinoma
What type of basal cell carcinoma presentation?
“enlarging scar”, white/yellow plaque with poorly defined borders more aggressive growth , induration ( thickening/hardening of skin )
Morpheaform Basal Cell Carcinoma
Surgical excision of what size lesion margins have shown 5 year cure rates exceeding 95%
4-5mm margins
When is it most appropriate to use electrodesiccation and curettage?
low risk superficial or nodular BCCs on the trunk or extremities
tumor suppressor gene on chrom 9
PTCH1
Merkel Cell Cancer is linked to what virus?
more aggresive than melanoma
Polyomavirus
Merkel cell Carcinoma – 90% involve 3 factors
AEIOU
Asymoptomatic
Expanding rapidly
immunosuppresive
older patients > 70 yo
UV exposure
appearance of sqamous cell carcinoma
actinic keratosis =
scaly plaque
squamous cell carcinoma mainly affects what areas?
ears, lips, temples, upper face and dorsum of hands
clinical presentation of SCC
Variant that grows rapidly ( 4-6 weeks ) and then spontaneously resolves =
KERATOACANTHOMA
clinical presentation of SCC
Ulcerating variant of SCC predisposed by chronic unstable burns/scars & draining osteomyelitis. Can metastasize rapidly after resection.
Marjolin’s Ulcer
TNM Staging
T1 < 1mm
T2 = 1.01-2 mm
T3= 2.01-4 mm
T4 > 4 mm
a= no ulcerations b= ulcerations
TNM staging
N0= no lymphatic metastases
N1= 1 lymph node involved
a= micrometastases
b= macrometastases N2
a= 2 lymph nodes involved
b= 3 lymph nodes involved N3= 4+ positive nodes
M= Distant metastases
M0= no distant metastases
M1=
a= metastases to distant skin, subcutaneous, and LN sites with normal LDH (LDH= sign of tissue damage ) b= lung metastases with normal LDH
c= metastases to other visceral sites with normal LDH or any metastases with
elevated LDH
TNM staging
N0= no lymphatic metastases
N1= 1 lymph node involved
a= micrometastases
b= macrometastases N2
a= 2 lymph nodes involved
b= 3 lymph nodes involved N3= 4+ positive nodes
M= Distant metastases
M0= no distant metastases
M1=
a= metastases to distant skin, subcutaneous, and LN sites with normal LDH (LDH= sign of tissue damage ) b= lung metastases with normal LDH
c= metastases to other visceral sites with normal LDH or any metastases with
elevated LDH
“itching condition”
T-cell mediated inflammatory disease
main issue = proliferation of keratinocytes
PSORIASIS
Keratinocyte injury/infection → increase of proinflammatory cells ( i.e. APCs ) that activate
T cells → T-cell mediated: CD4+ Th17 and Th1 cells & CD8+ T cells secrete growth
factors that cause keratinocyte hyperproliferation → leads to the formation of lesions
Histopath of Papulosquamous Rash:
Acanthosis = epidermal thickening
Increased epidermal cell degeneration ( leading to decreased epidermal thickening) above areas
of elongated dermal papillae
- Neutrophil aggregation in superficial epidermis
PSORAIAS
Auspitz’s sign
Clinical feature of psoriasis
pinpoint bleeding when scale is removed
6P’s describe this skin disorder
Pruritic, purple, polygonal, planar papules, and plaques
Lichen Planus
Pathology of what skin disorder?
autoimmune disorder results from CD8+ T cell mediated cytotoxic triggered against antigens in the basal keratinocyte cells and the dermo-epidermal junction –:> INFLAMMATION and necrosis
LICHEN PLANUS
Clincal presentation of which skin disorder?
Wickham Striae = papules have whites dots or lines
Melanin from damaged keratinocytes gives the lesions black color
Lymphocytes infiltrate dermoepidermal junction
Zigzag Contour
Civatte bodies/Colloid bodies = annucleate, necrotic basal cells seen in inflammed paillary dermis
Lichen Planus
known as balanitis xerotica obliterans (BXO) when it affects the penis
lichen sclerosis
Erythematous, scaly plaques with hyperpigmentation. Can lead to scarring, dyspigmentation, and alopecia if scalp is involved
Etilology = sun exposure, smoking, MHC-II/HLA-8, DR3, DR2 genetic associations
Histopath = epidermal atrophy, effacement of rete ridges, hyperparakeratosis, follicular kertoti plugging and basement membrane thickening with vacuolar interface change
Discoid Lupus erythematous (DLE)
Oval shaped erythematous, very pruritic, plaques/lesions with well-defined borders that occur on **upper and lower extremities **(drying of skins → causes lesions to recur at previously involved sites ) with scaling, oozing, and crusting
Nunmular Eczema = coin shaped eczema
exanthematas skin disease characterized by diffuse, scaling papules in T-shirt distribution after a viral prodrome
seen in young pateitns esp. women
Etiology = drug induced reactions
Pityriasis rosea
skin disorder primarily affects areas with sebaceous glands
- craddle cap in infants
- caused by a rxn to pityrosporum yeast on the skin
Seborrheic dermatitisi
ruffled sock appearance
loose anagen (cuticle folded back)
trichotillosis
habitual pulling and plucking of hairs
minoxidil and finasteride can be used in treatment of what?>
Alopecia