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67 Cards in this Set
- Front
- Back
Tumors of Dermis
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Benign Fibrous Histiocytoma (Dermatofibroma)
-Dermatofibrosarcoma Protuberans (DFSP) |
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Dermatofibroma
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Benign indolent neoplasms of dermal fibroblasts and histiocytes
Usually seen in adults, typically on legs (where antecedent trauma may occur) Tan-bown, firm papule (sometimes tender) Lateral compression (i.e. squeezing will cause central dimpling) |
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Dermatofibroma Histology:
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Nonencapsulated proliferation of spindle-shaped fibroblasts in dermis
May have numerous blood vessels and hemosiderin deposition (from prior trauma) |
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Dermatofibrosarcoma Protuberans (DSFP)
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Well-differentiated slow growing fibrosarcoma that is locally aggressive but rarely metastasizes
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Dermatofibrosarcoma Protuberans (DSFP) histology
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Cellular neoplasm composed of radially oriented growth of fibroblasts with a storiform pattern, mitoses are present
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Skin tumors derived from “cutaneous immigrants”
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Mast cells -> Mastocytosis
Histiocytes--> Histiocytosis Lymphocytes -> Lymphoma |
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Mastocytosis
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Increase in the number of mast cells mast cell degranulation releasing histamine and heparin causing symptoms of:
a. Pruritis, flushing, rhinorrhea, dermal edema and erythema b. Rubbing lesional skin makes a wheal (Darier’s sign), dermatographism |
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A form of mastocytosis that is localized to the skin with round to oval red-brown papules and plaques
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Urticaria Pigmentosa
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Urticaria Pigmentosa prognosis
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Generally favorable prognosis occurring mainly in infants and children
- 10% of cases may proceed to systemic mastocytosis (usually adults) and has poorer prognosis |
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MASTOCYTOSIS Giemsa stain highlights
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the granules within mast cells
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Mycosis Fungoides (MF) or Cutaneous T Cell Lymphoma (CTCL)
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Lymphoproliferative disorder that arises in the skin that eventually disseminates to lymph nodes and viscera
Usually affects patients >40 y/o |
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Mycosis Fungoides (MF) or Cutaneous T Cell Lymphoma (CTCL) lymphocytes affected become
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Atypical lymphocytes with cerebriform nuclei (Sezary-Lutner cells) that are CD4 + (helper T cells)
Express T cell receptor (TCR) gene rearrangement and lose T cell antigens |
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Mycosis Fungoides(CTCL) has 3 stages
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1. Patch stage
2. Plaque stage 3. Tumor stage |
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Mycosis Fungoides Patch stage:
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Erythematous, scaling patches that may itch severely
-May remain at this stage for several years |
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Mycosis Fungoides Biopsy (Bx) for patch stage shows
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lymphocytic epidermotropism (lymphocytes within epidermis) but diagnostic cells are not always present -> need to follow up with sequential bxs over time to make definitive dx (diagnosis)
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Mycosis Fungoides(patch stage) common in
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butt
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Mycosis FungidesLymphocytic epidermotropism
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lymphocytes going upward into the epidermis
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Mycosis Fungoides Pautrier’s
Microabscess |
cluster of atypical lymphocytes within epidermis
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Mycosis Fungoides . Tumor Stage:
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Reddish brown nodules that ulcerate
Lymph node and visceral involvement occur in up to 70% of cases Overall 5 year survival rate is less than 10% |
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Sezary’s Syndrome May be regarded as
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leukemic form of Mycosis Fungoides
Erythroderma is generalized Sezary cells are present in the blood |
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Sezary Syndrome can present in the face as
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Lionine facies
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Inflammatory Dermatoses
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Urticaria
Eczema |
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Urticaria
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Hives
Hereditary Angioneurotic Edema |
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Eczema
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Atopic dermatitis
Seborrheic dermatitis Allergic contact Drug related Photosensitvity |
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Urticaria (Hives)
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Hypersensitive (IgE) response to an antigen
IgE dependent degranulation of mast cells leading to pruritic,edematous wheals |
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Urticaria (Hives) May be due to
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antigenic exposure: pollen, foods, drugs, insect venom
May be due to nonantigenic stimulation: cold, heat, pressure, etc. |
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Several types of acute eczema (i.e. allergic contact, atopic, drug related, etc) that all have the same histology:
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Fluid accumulation in epidermis-> intercellular edema or spongiosis->intraepidermal vesicles
- Dermal edema with maybe eosinophils, lymphocytes -Overlying parakeratosis and sometimes serum crust |
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Types of Eczema
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Allergic contact dermatitis
Atopic dermatitis Seborrheic dermatitis Drug-induced dermatitis Photo-induced dermatitis |
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Allergic Contact Dermatitis
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Delayed hypersensitivity (i.e. poison ivy, rubber, perfume, nickel jewelry etc.)
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Allergic Contact Dermatitis Onset and pattern of rash distribution can be very helpful in
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detecting the offending agent
Detailed history important, including : Use of certain hygiene products,detergent,etc Contact with certain garments and shoes Occupational/environmental exposure |
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Seborrheic Dermatitis
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Common, red, scaly, itchy rash
Seen in areas of oil production: scalp, sides of nose, eyebrows, behind ears, mid-chest “Comes and goes” May be seasonally aggravated, especially in northern climates |
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Erythema Multiforme (E.M.)
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Self-limited hypersensitivity (cell mediated CD8 cytotoxic injury)
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Erythema Multiforme (E.M.) due to:
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Drugs (i.e. sulfamide, dilantin, barbituate, penecillin)
Infection (i.e.herpes, mycoplasma, ) Or idiopathic in 50% cases |
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Erythema Multiforme (E.M.) histological characteristic
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bull’s eye targetoid, vesiculo-bullous lesions
typically involve extremeties (especially palms and soles) |
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E.M. Major (or Steve’s Johnson Syndrome)
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Severe form of E.M. with mucous membrane involvement
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Erythema Multiforme Toxic Epidermal Necrosis (TEN)
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characterized by epithelial necrosis and sloughing of skin (analogous to burns)
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Erthythema Multiforme E.M. Minor histology:
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Focal basal keratinocyte degeneration (due to CD8 toxic injury) with eventual blistering
-Minimal perivascular lymphocytic infiltrates |
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T.E.N. histology:
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Necrosis involving full thickness of epidermis
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Panniculitis
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Inflammation of subcutaneous fat
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Panniculitis types
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Erythema Nodosum
b.) Erythema Induratum (Nodular vasculitis |
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Most common form of panniculitis
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Erythema Nodosum
Painful, tender nodules on lower anterior legs 3x more common on females Age of onset ~ 15-30 y/o |
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Erythema Nodosum Etiologic agents
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Infection (strep, herpes,fungal,etc)
Drugs (oral contraceptives, sulfonamides) Immune associated (ulcerative colitis, sarcoidosis, etc) |
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Erythema Nodosum Histology:
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Inflammation (occasional giant cells) and fibrotic thickening of fat septa
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Chronic, pruritic skin disorder with silvery, scaling, salmon pink papules and plaques in a characteristic distribution:
Elbows, knees, lumbo-sacral area, glans penis, palms and soles |
Psoriasis
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psoriasis demonstrate
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New lesions develop at sites of trauma (Koebner’s phenomenom=phenomenon may result from either a linear exposure or irritation)
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Psoriasis Acute onset
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Pustular Psoriasis
(Von Zumbusch Syndrome) with fever, arthritis and pustular lesions can be life threatening |
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Psoriasis Histology
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Parakeratotic and hyperkeratosis
Acanthosis Thinning of epidermis where it overlies dermal papilla Stratum granulosum is thinned or absent |
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Psoriasis Histology shows Munro’s abscesses
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- aggregates of neutrophils in epidermis
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Psoriasis Auspitz sign”
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removal of skin scale -> see tiny droplets of blood from the dilated blood vessels in dermal papillae
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Nail changes in Psoriasis
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Oil drop sign Pitting Onychodystrophy
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Lichen Planus
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Multiple, symmetrically distributed, Pruritic, Polygonal Papules -> Plaques
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Lichen Planus Distributed on
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wrist, shins, lumbar region, scalp alopecia
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Lichen Planus May have mucosal involvement:
buccal mucosa, tongue, lip Often highlighted by |
a network of white lines i.e. Wickman’s striae
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Serious autoimmune disease involving connective tissue and blood vessels
Exacerbated by sun (photosensitivity) Can be drug induced |
Lupus Erythematosus
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Systemic - acute Lupus Erythematosus may show a
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macular butterfly” rash
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Discoid Lupus Erythematosus
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Usually occurs in sun exposed areas
Sharply marginated scaly, atrophic, red plaques Scalp -> patches of alopecia |
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Histology of Discoid Lupus Erythematosus
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Lymphocytic infiltrates along D-E junction, around blood vessels and hair adnexae
Basal cell hydropic degeneration(vacuolization) Epidermal atrophy with follicular plugging Thickening of basement membrane |
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Lupus Erythematosus Pathogenesis
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Immune complex mediated and cell mediated injury
Serology circulating autoantibodies (i.e. antiDNA), rheumatoid factor |
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Lupus Erythematosus Immunofluorescence
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granular band of
Ig and complement along the D-E junction (“Lupus Band” test) |
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Infectious Entities
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Verruca (wart)
Molluscum contagiosum Impetigo Superficial fungal infection Arthrpod related infections |
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Verruca (wart)
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Benign epithelial hyperplasia manifesed by papules and plaques
Caused by Human Papilloma Virus (HPV) |
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Verruca (wart) Histology:
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Hyperplastic, papillated epidermis with koilocytotic (viral) changes shown by :
Irregular nuclei surrounded by cytoplasmic halo Prominent basophilc granules in cytoplasm |
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Molluscum Contagiosum
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Discrete, umbilicated, pearly white papules may occir in neck, trunk, anogenital area, eyelids
caused by pox virus |
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Impetigo
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Strep or Staph skin infection
Usually seen in babies, young children or sick adults Sites: face, hands, trunk, intertriginous areas |
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Impetigo Histology:
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Subcorneal pustules with
gram + cocci and neutrophils |
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Superficial Fungal Infection Dermatophytosis – Tinea
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Caused by dermatophytes ( fungi that thrive only in nonviable keratinzed tissue (i.e. stratum corneum, nails, hair)
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Scabies
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Contagious, pruritic infection caused by sarcoptes scabei (female mite) burrows in stratum corneum lays eggs and fecal matter
Involves interdigital skin (webs between digits), genital skin |