skin Flashcards
What characterizes Icthyosis Vulgaris?
Mild hyperkeratosis and reduced or absent keratohyaline granules in the epidermis.
It is an AD disorder or keratinization
Why does scaly skin develop in Icythyosis Vulgaris?
Increased cohesiveness of the stratum corneum
What defect is noted in Icythoiss Vulgaris
small defective keratohyaline granjules are in the stratum granulosum
Who is likely to be seen with Lentigo maligna melanoma?
Fair-skinned, elderly, whites, outdooor workers-those exposed to the sun (withouth acute episodes of sunburn_
What is characteristic of Lentigo maligna melanoma?
- It occurs in areas of body exposed to sun
- it is a large, pigmented macule that occurs on sun-damaged skin
Descrive 3 clinical findings in a patient with Kaposi Sarcoma
- Capillary Hemangioma
2 highly cellular and vascular spaces
Epidermolysis Bullosa is characterized by what feature?
tendency to form blisters at sistes of minor trauma. Blisters are almost always noticed at birth or shortly after
What mutations are often affiliated with Epidermolysis Bullosa?
Mutations of genes encoding the cytokeratin IF
What is expected to be found in the immunoflourescence microscopy of both Pemphigus Vulgaris and Bullous Pemphigoid ?
Immunoglobulin deposits (IgG antibodies against desmosomes and hemidesmosomes respectively)
IgG surrounding keratinocytes has a fish net pattern in pemphigus vulgaris
Bullous Pemphigoid should show linear deposition of C3 and IgG along the epidermal basement membrane zone.. Basement membrane proteins, BPAG1 &2 are the two targets of complement-fixing igG antibodies.
Which proteolytic enzyme may be the dominant factor in dyshesion seen in pemphigus vulgaris?
Plasmin. Plasminogen activator is released after immune complex formation which further augments dyshesion
What does a BCC tumor consist of?
Basophilic epithelial cells with narrow rims of cytoplasm that attach to the epidermis and protrude the subjacent papillary dermis.
What are some features of Erythema Nodosum?
- Self-limiting non-suppurative, tender nodules over the extensor surfaces of the lower extremities that is triggered by microorganisms or drugs and is associated with various systemic disease
Where in the skin doe immune complexes from SLE deposit?
beneath the epidermal basement membrane zone.
How does hyperkeratosis occur in Lichen planus?
the epidermal cells is treated as an antigen and induces local macrophage activation and lymphocytic proliferation which disrupt the stratum basalis and cause reactive epidermal proliferation
Histological marker of Mycodis Fungoides
Presence of lymphocytes int he epidermis (Epidermotropism)
What are the three names for the disorder known for “palpable purpura”
- Hypersensitivity angiitis
- Cutaneous Necrotizing vasculitis (CNV)
- Leukocytoclastic Vasculitis
What causes CNV?
circulating immune complexes deposited in vascular walls. C5a attracts neutrophils which degranulate and release lysosomal enzymes, resultiin endothelial damage and fibrin deposition.
Erythema Multiforme is a hypersensitivity response to what?
Certain infections and drugs, such as sulfonamides and penicillin.
Other inciting factors include HSV, Mycoplasmal and fungal infections, malignant diseases, and collagen vascular diseases such as SLE.
What is the differential for a subcutaneous nodule?
Dermatofibroma
Intradermal Nevus
What can cause Hansen disease?
Mycobacterium leprae
How does Hansen disease manifest?
areas of skin anesthesia that predispose to repeated trauma
What is Erysipelas?
An acute infection of the upper dermis and the superficial lymphatics that is often caused by streptococcus pyogenes
. (S. pyogenes also causes ipetigo an dscarlet fever)
Panniculitis
Panniculitis is a group of diseases whose hallmark is inflammation of subcutaneous adipose tissue
What is charactaristic of Urticaria pigmentosa? What mutation is associated with it?
Darier sign on rubbing
Point mutations in the C-KIT oncogene
