Lecture 2 Flashcards
Overview of Dermis Layers
Connective tissue of messenchymal origin- between epidermis and Hypodermis.
Fibrous made up of collagen and elastic fibers.
Layers of Dermis
Papillary layer - deep to epidermis made of loose vascular connective tissue.
Reticular layer - thick layer of dense connective tissue makes up the majority of the dermis. Contains blood vessels, glands, hair follicles, lymphatics, nerve and fat cells.
Ehlers-Danlos Syndrome (EDS)
Genetic disorder that leads to a defective and weakened collagen.
EDS Secondary issues
Connective tissue, tendon, and ligament weakness, tears, limb differences, scoliosis, ruptured arteries or organs, malshaped cornea, heart or vascular issues, weak or brittle bones.
Marfan Syndrome
A defect in the gene that encodes the structure of fibrillin and elastic fibers.
Marfan Sundrome gene
fibrillin-1 or FBN-1
Two common co-morbidities for Marfan
60%- have scoliosis
90% have changes in the heart and blood vessels.
Disorders of the Dermal Region
- Aortic Aneurysm - (most commonly at aortic root where aorta leaves heart)
- Aortic dissection - (can be fatal)
- Heart valve problems (prolapse) - Marfan can cause.
- Cardiomyopathy - (heart enlarges and weakens over time)
- Abnormal heart rhythm- (Arrhythmia)- often related to mitral valve prolapse, and can cause brain aneurysms.
- Intercranial bleeding- (from ruptured aneurysm.
Macule , Patch
Flat nonpalpable change in skin color. Smaller than 1 cm have defined border. Larger than 1 cm have irregular borders.
Ex. Macules- freckles, measles, petchiae. Patches- Port wine stains, vitiligo and cholasma
Papule, plaque
Elevated solid, palpable mass with defined border. Papules are smaller than 0.5cm; plaques are groups of papules that form lesions larger than 0.5 cm.
Ex. Papules- moles, warts, lichen planus. Plaques- psoriasis, actinic keratosis and lichen planus.
Nodule, tumor
Elevated, solid, hard or soft palpable mass that extends deeper in the dermis. Nodules have defined borders and are 0.5-2.0cm; tumors may have irregular borders and are larger than 2cm.
Ex. Nodules- small lipoma, squamous cell carinoma, fibroma, intradermal nevi.
Tumors- large lipoma, carcinoma, hemangioma.
Vesicle, Bulla
Elevated, fluid-filled, round or oval shaped palpable mass with thin, translucent walls and defined borders. Vesicles are smaller than 0.5cm, bullae are larger than 0.5.
Ex. Vesicles- herpes simplex/zoster, early chickenpox, poison ivy, small burn blisters.
Bullae- contact dermatitis, friction, blisters, and large burn blisters
Wheal
Elevated, reddish area with irregular border caused by diffuse fluid in tissues rather than free fluid in a cavity (which would be a vesicle). Size varies.
Ex. Insect bites, hives
Pustule
Elevated, pus-filled vesicle or bulla with defined border. Size varies.
Ex. Acne, impetigo, carbuncles (large boils)
Types of skin cancer
- Basal cell carcinoma- comes from stratum basale, 99% curable if caught early. Some shaped nodules form ulcer in the center.
- Squamous cell carcinoma - comes from stratum spinosum, grows quickly and metastasizes if not removed. Small red rounded elevation on skin.
- Melanoma- cancer of melanocytes (v dangerous) 5% of skin cancers but rising. Can come from preexisting moles. Appears as spreading brown or black patch. Poor survival rate of lesion is larger than 4mm thick.
