Week 3: Derm Flashcards
The skin has 2 layers:
- Epidermis
2. Dermis
The epidermis is the:
Outer highly differentiated later.
The dermis is the:
Inner supportive layer
Melanin is found in what layer?
The epidermis
The epidermis has 2 layers:
- Stratum corneum- outer horny layer
2. Cellular stratum
The outer horny layer of the epidermis is:
A layer of dead keratinized cells and is the derivation of skin color.
The dermis is made up of:
Connective tissue or collagen,elastic tissue, sensory nerve fibers, blood vessels, sebaceous glands, and hair follicles.
Epidermal appendages include:
Hair
Sebaceous glands
Sweat glands
Nails
Types of sweat glands:
Eccrine
Apocrine
Type of sweat gland that opens directly onto the surface of the skin and regulates body temperature through water secretion.
Eccrine
This is formed by epidermal cells that invaginate into the dermal layers.
Hair
Type of hair that is short, fine, and nonpigmented:
Vellus
Type of hair that is coarser, longer, thicker, and usually pigmented:
Terminal
These secrete sebum and are under control of sex hormones (primarily testosterone).
Sebaceous
Sebum in the newborn:
Holds water in the skin, is present for the few weeks of life and produces milia and seborrheic dermatitis (cradle cap).
When do eccrine sweat glands secrete in response to heat in infants?
Do not start to secrete until the first few months of life and then only minimally throughout childhood.
Questions to ask for subjective data r/t derm:
Past hx of skin disease, allergies, hives, psoriasis, or eczema?
Change in color?
Change is mole size, shape, color, and tenderness?
Itching?
Bruising?
Rash or lesions?
Medications?
What is the most common of skin symptoms?
Pruritus
Angle of nail base should be:
About 160 degrees
Abcde rule to detect suspicious lesions:
A- asymmetry B- border C- color D- diameter E- elevation and enlargement
What type of microscopic examination of skin scrapings can be used to examine for fungal disorders (hyphae or spores)?
Potassium hydroxide (KOH)
Round lesions:
Annular or circular
Lesions that flow/come together:
Confluent
Lesions that do not become blended:
Discrete
Lesions that cluster together:
Grouped
Lesions that are whirling in a circle:
Gyrate
Lesions in concentric rings:
Target or iris
Lesions that are in a line:
Linear
Lesions that are merged circles:
Polycyclic
Lesions that are band-like, unilateral, and are located along the cutaneous distribution of dermatome:
Zosteriform
A macule is:
Solely color change, flat and circumscribed
Less than 1 cm*
Examples of a macule:
Freckles, flat nevi, hypopigmentation, petechiae, measles, scarlet fever
What is a Papule?
Something you can feel, less than 1 cm caused by superficial thickening in the epidermis
Examples of a papule:
Elevated nevus, lichen planus, molluscum, wart (verruca)
What is a patch?
Macules that are larger than 1 cm
Examples of a patch:
Mongolian spit, vitiligo, cafe au lait spot, chloasma, measles rash
What is a plaque?
Papules that coalesce to form surface elevation wider than 1 cm
Examples of a plaque?
Psoriasis, lichen planus
What is a nodule?
Solid, elevated, hard or soft, and larger than 1 cm. May extend deeper into dermis than a papule
Examples of a nodule:
Xanthoma, fibroma, intradermal nevi