Dermatlogy Flashcards
Which skin disease is normally found on extensor surfaces?
Psoriasis
Which skin diseases are normally found on flexor surfaces?
Atopic eczema
What is Koehler phenomenon
Psoriasis where scratch has occured on the skin
Singular circle rash is known as?
Annular (granuloma annular)
Multiple circles of rash is known as?
Tinea (ringworm)
What does dermatomal mean?
In a dermatome distribution, area of skin supplied by a nerve
What is a macule?
Flat mark on the skin, lacking or overstimulating pigment can also be red, usually <1cm
What is a papule?
Small solid elevation of the skin, <5mm in diameter.
Describe Lichen Planus
Flat topped papule
Describe a xanthoma
Dome shaped papule
What is a nodule?
Similar to a papule but greater than 5mm can be oedematous or solid. (Raise in the skin)
What is a bulla?
Large blister greater than 5mm in diameter containing fluid
What is a vesicle?
Small blister <5mm in diameter, consists of clear fluid within or below epidermis (chicken pox)
What is a pustule?
Blister less than 5mm with a visible collection of free pus
What’s a furuncle?
Infected pustule
Example of a sterile pustule?
Pustular psoriasis
What is a cyst?
A nodule consisting of a epithelial-lined cavity filled with fluid or semi solid material
What is a plaque?
A palpable, plateau like elevation of abnormal skin >2cm in diameter, group of papules that coalesce = plaque
What is a scale?
Thickened horny layer (keratin) with readily detaching fragments.
What is an ulcer?
Circumscribed area of skin loss
What is an arterial ulcer?
A.k.a gangrene in the arterial area, usually on lower feet/ankle such as toes, shins and other pressure points. Pinpoint, small, deep and painful. Regular borders.
What is a venous ulcer?
Usually an ulcer of the venous system, on foot/ankle larger more irregular borders. Found on malleolus usually. Large shallow less painful.
What is a malignant ulcer?
Tumour outstrips its own blood supply
What is lichenification
Shining of the skin due to chronic scratching
What is purpura?
Extravasion of blood resulting in red discolouration of the skin
What is ecchymosis
Macular red or purple haemorrhage more than 2mm in diameter (purpura but bigger)
What is crust?
Soemthing easily wiped off, usually blood serum or pus
What is an erosion?
Superficial break in the epidermis not extending into the dermis. Heals without scarring
What is an excoriation?
Superficial abrasion often linear due to scratching
What is a naevus?
A mole, normal hyperplasia of a normal constituent of the skin
What bacteria causes impetigo?
Staph aureus
What bacteria causes ecthyma and carbuncle?
Staph aureus
What bacteria causes cellulitis?
Strep pyogenes
What bacteria causes erysipelas?
Strep pyogenes
What bacteria is included in the normal skin flora?
Staphylpoccoci (20%), micrococci, corynebacteria and propionibacteria
What bacteria causes acne?
Propionibacteria acne
What is a common viral skin infection?
Warts (verrucae)
What herpes simplex virus causes cold sores?
HSV-1
What herpes simplex virus causes genital herpes
HSV-2
What causes shingles?
Herpes zoster
What causes chicken pox?
Varicella zoster
What is molluscum contagious
Water warts, caused by pox virus
What des dermatophytes infect?
Skin, nails and scalp
What is pityriasis versicolour
Pigmentary skin changes revealed by tanning in the sun
Pedicures is another name for what?
Lice
What acne affects the older popualtion?
Acne rosacea
What are the 3 types of non-melanoma skin cancer?
- Basal cell carcinoma 2. Bowens disease 3. Squamous cell carcinoma
Basal cell carcinoma
- firm nodule. Ulcer in the middle, pearly edge, takes years to grow, never metastasises
Bowens disease
Crusted erythematous plaque, middle age-elderly patients, trunk and limbs
Squamous cell carcinoma
Often develops on sites of previous sun damage, thickened keratotic nodule with a poorly defined edge. Dilated telangiectatic blood vessels
Malignant melanoma?
50% of all UK cases, commonest on lower leg. Irregular border more than 2 colours, develops in a long standing freckle = lentil malignant melanoma
Diagnosis of melanoma key points 6.
- Size (increase) 2. Shape (irregular) 3. Colour (variation) 4. Inflammation (may be at the edge) 5. Crusting (ooze/bleed) 6. Itch (common)
What is the ABCDE criteria in dermatology
A= asymmetric shape B= border irregular C= colour variegated D= diameter greater than 6mm E=elevation of a flat mole
Describe a patch
Larger than a 1cm, big and flat
What is scabies?
Marks around the hand and groin area showing burrowing in the skin, linear white lines
What are the 3 layers of the skin?
- Epidermis
- Dermis
- Subcutaneous tissue (adipose)
What are the 2 subdivisions of the dermis?
Squamous and basal
5 functions of the skin
Temp regulation, immunity, barrier, sun uv protection, vitamin D production, water loss prevention, attraction, sensation
Lotion Bases in order 5
- Solution
- Gel
- Lotion
- Cream
- Ointment