2 Dermatology Flashcards
Functions of epidermis?
- barrier from environment
- waterproofing
What is in the dermis?
- blood vessels
- hair follicles
- sebaceous glands
- sweat glands
- nails
- apocrine glands
What is in the subcutaneous (hypodermis)?
-subcutaneous fat and connective tissue
conserves heat
What are the layers of epidermis?
“can lucy get some balm”
- Stratum corneum: superficial with shedding dead skin
- Stratum lucidum: layer found on palmar and plantar surface
- Stratum granulosum: keritinization
- Stratum spinosum: spiny-chaped cells (strength/flexible)
- Stratum basale: cells germinate: keratinocytes
What are the 4 types of cells within the epidermis?
- keratinocytes
- melanocytes
- merkel cells
- langerhans cells
what are 3 layers of dermis?
-papillary dermis
superficial dermis
comprised of a loose network of collagen buncles
-reticular dermis
deep dermis
comprised of densely packed and thick collagen bundles
-ground substance
What is the function of eccrine glands and where?
- produce sweat
- cover most of the body
- abundant on palms, soles and forehead
- release salt and water to keep body cool
- does not cause odor (does when mixed with bacteria on skin surface)
- Duct opens in pore at skin’s SURFACE
What is the function of apocrine glands and where?
-produce thick clear odorless fluid (unless bacteria on surface breat them down and make odor)
-concentrated in axillary and genital regions
-Secretes into the SAC of hair follicle
-triggered by nervous system:
stress, exercise, hormones, emotion
What are two types of hairs and what is the bulb?
-vellus hairs: short and fine (forehead)
-Terminal hairs: long and thick (scalp/axillae)
-Bulb: enlargement at the base of follicle
matrix cells at inferior aspect of bulb
melanocytes within matrix contribute to pigment
What are morphologic characteristics of skin leasons?
- distribution
- shape/arrangement
- border/margin
- pigmentation/color
- palpation
Distribution- what does localized mean?
lesions appear in one small area
Distribution- what does regional mean?
lesions appear in a specific region of the body
Distribution- what does generalized/disseminated mean?
lesions appear widely distributed or in multiple areas simultaneously
What is common with distribution of flexors?
atopic eczema
What is common with distribution of extensors and scalp?
psoriasis
What is common with seborrhoeic distribution?
seborrhoeic dermatitis on scalp and upper chest
What is common with sun-exposed sites?
light sensitive disorders
What does morbilliform shape mean?
- measles-like
- erythematous maculopapular lesions that become confluent on the face and body
What are the ABCDEs of melanoma?
- A: asymmetry
- B: borders (irregular)
- C: color (variegated)
- D: diameter
- E: evolution or elevation
What is a macule?
-flat, non-palpable
*< 1 cm in diameter
-circumscribed color change
-ex. freckles (ephelides)
1
What is a patch?
-flat, non-palpable
-can have irregular shape
* > 1 cm in diameter
-often hypo or hyperpigmented
-ex. cafe au lait
1
What is a papule?
-Palpable, firm
*< 1 cm in diameter
-circumscribed
-can be flesh colored, red, brown
-may be confluent
-ex. seborrheic keratosis
1
What is a plaque?
-elevated
-firm
-palpable
* > 1 cm in diameter
-ex. psoriasis
1
What is a nodule?
-elevated
-circumscribed
*often > 1.5 cm in diameter
-deeper and firmer than papule
-can be compressible, soft, rubbery, or firm to palpation
-ex. epidermoid inclusion cyst
1
What is a tumor?
-a large nodule
-deeper in the dermis
* > 2 cm in diameter
-ex. lipoma (benign subcutaneous soft tissue tumor)
1
What is a wheal?
-irregular
-transient: comes and goes
-superficial edema
-ex. hives (urticaria), mosquito bite
1
What is a vessicle?
-elevated
-well circumscribed
* < 1 cm in diameter
-fluid-containing, usually clear
-ex. chickenpox “dew drops on a rose petal”
1
What is a bulla?
-elevated
-well circumscribed
* > 1 cm diameter
-filled with serous fluid
-plural of bulla is bullae
-ex. bullous pemphigoid
1
What is a pustule?
-elevated
-superficial
-well circumscribed
-filled with pus
-ex. folliculitis
1
What is a furuncle?
-infection of a SINGLE hair follicle
-S. aureus
-also called a boil
1
What is a carbuncle?
-infection of MULTIPLE hair follicles
-S. aureus
-an result from abscess
1
What is crust?
-dried residue of serum, pus, or blood on the surface
-adherent
-may include bacteria
-ex. impetigo
2
What is scale?
-hyperkeratosis
-accumulation of stratum corneum due to increased proliferation and/or delayed desquamation
-ex. psoriasis (micaceous- silvery- scale)
2
What are fissures?
-linear cleft in skin
-often painful
-results from marked drying, skin thickening, and loss of elasticity
-ex. cracks on hand in knuckles
2
What is erosion?
-partial, or sometimes complete. loss of the epidermis
-moist, oozing, and/or crusted lesion
-ex. pemphigus foliaceus
2
What is an ulcer?
-a deeper defect (compared to an erosion), with loss of at least the entire epidermis PLUS superficial dermis
-may have loss of the entire dermis or even subcutis
-ex. venous (stasis) ulcer
2
What is excoriation?
-exogenous injury to all or part of the epidermis
-may be linear or rounded
-usually due to scratching
-ex. neurotic excoriations
2
What is atrophy?
-epidermal atrophy: thinning of the epidermis, leading to wrinkling and a shiny appearance
-Dermal atrophy: loss of dermal collagen and/or elastin, leading to a depression
-ex. striae (stretch marks) due to topical steroid use
2
What is lichenification?
-thickenig of the epidermis
-increased visibility of skin markings
-ex. lichen simplex chronicus
2
What is petechiae?
-deep red/purple-red lesions
*< 0.5 cm
-round
-irregular
*non-blanchable
-variable distribution
-represents blood outside of vessel
-seen with infections and bleeding disorders
V
What is purpura?
-deep red/purple-red lesions
* >0.5 cm
-round
-irregular
* non-blanchable
-variable distribution
-represents blood outside of vessel
-seen with infections and bleeding disorders
V
What is ecchymosis?
-aka bruising
-purple lesions of variable size
-fade to green, yellow, brown
-round/oval
-irregular borders
-represents blood outside of vessels due to trauma or bleeding disorder
V
What is a spider angioma?
-fiery red lesion
-small in size (up to 2 cm)
-central body with surrounding erythema and radiating legs
*blanch with pressure
-seen on face, neck, arms and upper trunk
-usually develop in otherwise healthy women and children
-seen with liver disease
-pregnancy (often a normal finding)
V
What is a cherry angioma?
-bright red papules
-1-6 mm in size
-can be flat or raised
-non-pulsatile
-usually seen on the trunk or upper extremities
*non blanchable
-associated with genetic and aging
V
What are telangiectasias?
-permanently dilated superficial cutaneous blood vessels
-red to blue-violet in color
*blanchable
-fine
-irregular
-seen with basal cell carcinomas, sun-damaged skin, rosacea
V
What is hemangioma?
*benign vascular neoplasm that represents the most common tumor of infancy
-red, irregular lesion seconary to dilation of dermal capillaries
-starts as a macular patch, can progress to a plaque or nodule
-spontaneously involutes by age 5-10
V
What does umbilicated mean?
rolled borders
What are 4 categories of skin disease?
- papulosquamous
- nodular
- vesiculobullous
- maculopapular
What are papulosquamous lesions?
- papules, plaques and scales
- ex. psoriasis
What is lichen planus? hint the 5 P’s
- pruriticy
- polygonal
- purple
- planar
- papules
What are nodular lesions?
-benign and malignant epidermal and dermal nodules
-ex. of benign lesions
nevi
cherry angiomas
epidermoid cysts
-ex. of malignant lesions
-squamous cell carcinoma
isolated keratotic, eroded papule or nodule
located in sun exposed areas
-basal cell carcinoma
pearly nodules in sun exposed areas
associated with central ulcerations and telangiectasias
-ask how long has it been there
What are vesiculobullous lesions?
- vesicles and bullae
- ex. impetigo, herpes, pemphigus
What are maculopapular lesions?
-macules and papules
-ex. viral exanthems
generalized, erythematous, macuopapular rash
-drug eruptions
What is clubbing of the nail?
-rounded, bulbous nail base
-feels spongy
Diagnose by:
-flex the fingers of both hands
-bring index fingers together until distal phalanxes are touching
-diamond space between nails indicates no clubbing
Schamroth’s window
Schamroth’s sign
associated with lung cancer?
What are Beau’s lines?
-transverse depressions secondary to trauma or acute illness
-lines grow out with nail
fingers take 6m
toes take 1y
What is paronychia?
- inflammation of the proximal and lateral nail folds
- accute < 6 weeks
- chronic > 6 weeks
What is onychocryptosis?
- ingrown toenail
- usually involving the large toe
- very common
- nail grows into the dermis
- may have pain
- can become infected
What are Terry’s nails?
- mostly white with a distal band of reddish brown
- characteristic “ground glass” appearance
- without any lunula
What is leukonychia?
-trauma to nails causing areas of white discoloration
What is koilonychia?
- “spoon nail”
- spoon shaped, concave nail
- iron deficiency
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
- common with increased age
What is nail pitting?
- small punctate depressions
- caused by nail matrix inflammation
- associated with hair loss
