Intro To Derm Flashcards
What are the 3 layers of the skin?
Epidermis, dermis, and subcutaneous (hypodermis)
What layer of skin are the blood vessels, hair follicles, sweat glands, apocrine glands, and sebaceous glands in?
The dermis
List the 5 layers of the epidermis in order.
Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale
(mnemonic = Californians Like Girls in String Bikinis)
List the 4 types of cells in the epidermis
Keratinocytes, melaocytes, Meckels cells, and langerhans cells
What type of epidermis cell does basal and squamous cell carcinoma occur in?
Keratinocytes
What type of epidermis cell does melanoma occur in?
Melanocytes
What layer of the epidermis does Keratinization occur in?
Stratum granulosum
List from most superficial to deep the layers of the dermis.
Papillary dermis, reticular dermis, and ground substance
What layer of the skin are the fibroblasts, macrophages, and adipose tissue in?
The hypodermis
Where are eccrine glands most abundant?
Palms, soles, and forehead (but also present over most of the body)
What do eccrine glands do?
Releases odorless salt and water to keep the body cool
Where are apocrine glands most abundant?
Axillary and genital regions
What do apocrine glands do?
These are traditional sweat glands, they release a thick clear odorless fluid.
** Bacteria that lives on the skin break down apocrine secretions which leads to body odor **
What are apocrine glands triggered by?
The nervous system- stress, exercise, hormones, and emotions
What are vellus hairs? Ex of where they are located
Short and fine hairs
Ex) hair on forehead
What are terminal hairs? Ex of where they are located
Long and thick hair
Ex) scalp and axillary hair
What are the functions of the skin?
Protect from trauma and infection, prevent fluid loss, regulate body temperature, provide sensory information, and produce vitamin D
How do you assess skin turgor?
Pinch a section of skin on the forearm and it should return to place immediately
What does nummular mean?
Coin shaped
What does annular mean?
Round with active margins and central clearing
Ex) tinea infections
What does dermatomal mean?
It follows a nerve segment. Seen in herpes or varicella zoster
What are target lesions?
Pink macules with purple central papules.
ex) seen in erythema multiforme
What kind of shape does phytophotodermatitis have?
Linear
What is a morbilliform rash?
A measles like rash - erythematous maculopapular lesions that become confluent on the face and body
What does it mean if a rash blanches?
If you press on the rash, the redness goes away
What are the ABCDEs of melanoma?
A- asymmetry B- Borders C- color D- Diameter E- Evolution or elevation
What are primary lesions?
Lesions that arise from previously normal skin
What are secondary findings in regards to lesions?
Secondary findings arise from changes in primary lesions, usually due to exogenous factors or changes
Ex) scratching, infection, rubbing, crusting
Describe a macule.
A flat, non-palpable, less than 1 cm in diameter circumscribed color change
Ex) freckles
Describe a patch.
A flat, non-palpable, greater than 1 cm in diameter hypo or hyperpigmented spot. Can have an irregular shape.
Ex) Cafe Au Lait spots
What are the two types of primary lesions that are flat and non-palpable?
Macules and patches
What are the 3 types of primary lesions that are superficial elevations causes by free fluid?
Vesicles, bulla, and pustules
What are the 5 types of primary lesions that are palpable, elevated, solid masses?
Papules, plaques, nodules, tumors, and wheals
Describe a papule.
A palpable, firm, less than 1 cm in diameter, circumscribed lesion. Can be flesh colored, red, or brown.
Ex) seborrheic keratosis
Describe a plaque.
Elevated, firm, palpable, and greater than 1 cm in diameter.
Ex- Psoriasis
Describe a nodule.
Elevated, circumscribed, and often greater than 1.5cm in diameter. Deeper and more firm than a papule. Can be compressible, soft, or rubbery to palpation
Ex) epidermoid cyst
Describe a tumor.
A large nodule that is deeper in the dermis. Greater than 2cm in diameter.
Ex) lipoma
Describe wheals.
Irregular and transient superficial edema.
Ex) hives
Describe vesicles.
Elevated and well circumscribed, fluid containing lesions. Less than 1 cm in diameter.
Ex) chicken pox- dew drops on a rose petal
Describe bulla.
Elevated, well circumscribed, serous fluid filled lesions that are greater than 1 cm in diameter.
Ex) bulbous pemphigoid
Describe a pustule.
Elevated, superficial, well circumscribed, pus filled lesion.
Ex) folliculitis
What is a furuncle?
An infection of a single hair follicle. AKA boil.
Often caused by staph aureus
What is a carbuncle?
Infection of multiple hair follicles. Can form abscess and require I&D. Often caused by Staph aureus
Are furuncles and carbuncles primary or secondary lesions?
Primary
What are the types of secondary lesions?
Crust, scale, fissure, erosion, ulcers, excoriation, atrophy, and lichenification
Describe crusting.
Dried residue of serum, pus, or blood on the surface of skin.
Ex) impetigo
What is scale? What layer of the skin does this accumulate from?
Hyperkeratosis and Accumulation of stratum corneum due to increased proliferation and/or delayed desquamation
Ex) psoriasis
What is a fissure?
A linear crack in the skin that results from drying, skin thickening, and loss of elasticity. Often painful and on the hands
What are erosions?
Partial or sometimes complete loss of the epidermis. Can be moist, oozing, or a crusted lesion.
Ex) pemphigus foliaceus
What is an ulcer? What layers does it involve?
A deep defect with loss of at least the entire epidermis plus superficial dermis.
Ex) Venous ulcer
What are excoriations?
Exogenous injury to all or part of the epidermis. Usually due to scratching and may be linear or rounded
Ex) neurotic excoriations
What is epidermal atrophy?
Thinning of the epidermis leading to wrinkling and shiny appearance
What is dermal atrophy?
Loss of dermal collagen and or elastin leading to depression
What is lichenification?
Thickening of this epidermis and increased visibility of skin markings.
Ex) lichen simplex chronicus
What are the 7 vascular lesions?
Petechiae, purpura, ecchymosis, spider angiomas, cherry angiomas, telangiectasias, and hemangiomas
Describe petechiae.
Deep red/purple round and irregular lesions that are non-blanchable. Less than 0.5cm in diameter
When is petechiae often seen?
Infections and bleeding disorders
Describe purpura.
color/size/shape/blanchable or not
Deep red/purple round and irregular lesions that are non-blanchable. Greater than 0.5cm in diameter
When is purpura often seen?
Infectious and bleeding disorders
What is ecchymosis?
Bruising. Represents blood outside of vessels due to trauma or bleeding disorders
Describe spider angiomas.
color/size/shape/blanchable or not
Small Fiery red lesions with a central body and surrounding erythema with radiating legs. *Blanches with pressure.
Where are on the body are spider angiomas normally seen?
Face, neck, arms, and upper trunk.
What populations are spider angiomas frequently seen on?
Usually develops in otherwise healthy women and children. Also often seen with liver disease and pregnancy
Describe cherry angiomas.
color/size/shape/blanchable or not
Bright red papules that range from 1 to 6 mm in size. Can be flat or raised. Non pulsatile and *non blanchable.
What are telangiectasias?
color/blanchable or not
Permanently dilated superficial cutaneous blood vessels. Red to blue-violet in color. Blanchable.
When are telangiectasias typically seen?
Basal cell carcinomas, sun damaged skin, and rosacea
What is a hemangioma? When is it common?
A benign vascular neoplasm that represents the most common tumor of infancy
Describe the presentation of a hemangioma.
A red irregular lesion secondary to dilation of dermal capillaries. Starts as a macular patch, but can progress to a plaque or nodule.
What are the 4 categories of skin disease?
Papulosquamous, nodular, vesiculobullous, and maculopapular
What is an example of a papulosquamous lesion?
Psoriasis
What are the 5 Ps of lichen planus?
Pruritic Polygonal Purple Planar Papules
What are nodular lesions? Examples?
Benign and malignant epidermal and dermal nodules.
Ex) cherry angiomas, epidermoid cysts, and nevi
What is the presentation of squamous cell carcinoma?
Isolated keratotic, erodes papule or nodule that is located in sun exposed areas
Describe the presentation of basal cell carcinoma.
Pearly nodules in sun exposed areas. Associated with central ulcerizations and telangiectasias
What type of lesions are viral exanthems and drug eruptions typically?
Maculopapular lesions
Describe clubbing on the nail.
Rounded bulbous nail base with a spongy feel
How do you diagnoses clubbing of the nail?
Ask patient to flex fingers of both hands and bring index fingers together until distal phalanges are touching. If the diamond space between the nails is gone (Positive schamroths sign) the patient has clubbing
What are beaus lines?
Transverse depressions secondary to trauma or acute illness. The lines will grow out.
What are paronychias?
Inflammation of the proximal and lateral nail folds
What is onychocryptosis?
An ingrown toenail. Usually on big toe the nail grows into the dermis. Can be infected.
What are terry’s nails?
Nails that are mostly white with a distal band of reddish brown. Lunula is gone.
Characteristic “ground glass” appearance
What is leukonychia?
Trauma to the nails causing areas of white discoloration
What is koilonychia?
Spoon shaped, concave nail
What is onycholysis?
Painless separation of the nail plate from the nail bed.
What is onychomycosis?
Fungal infection of the nail bed, plate, or matrix.
What is nail pitting?
Small punctuate depressions in the nail caused by nail matrix inflammation.
What does positive schamroths sign indicate?
Clubbing
