FINAL derm Flashcards
This is the most serious type of skin cancer, develops in the cells (melanocytes) that produce melanin — the pigment that gives your skin its color
It is becoming more common in people younger than 40, with a higher prevalence in women.
Melanoma
The first melanoma signs and symptoms often are:
A change in an existing mole
The development of a new pigmented or unusual-looking growth on your skin
(Melanoma doesn’t always begin as a mole. It can also occur on otherwise normal-appearing skin.)
To help you identify characteristics of unusual moles that may indicate melanomas or other skin cancers, think of the letters ABCDE. What do the letters stand for?
-A is for asymmetrical shape. Look for moles with irregular shapes, such as two very different-looking halves.
-B is for irregular border. Look for moles with irregular, notched or scalloped borders — characteristics of melanomas.
-C is for changes in color. Look for growths that have many colors or an uneven distribution of color.
-D is for diameter. Look for new growth in a mole larger than 1/4 inch (about 6 millimeters).
-E is for evolving. Look for changes over time, such as a mole that grows in size or that changes color or shape. Moles may also evolve to develop new signs and symptoms, such as new itchiness or bleeding.
Melanomas can also develop in areas of your body that have little or no exposure to the sun, such as the spaces between your toes and on your palms, soles, scalp or genitals.
These are sometimes referred to as hidden melanomas because they occur in places most people wouldn’t think to check.
Melanoma is more likely to occur in a hidden spot in people with which type of skin?
Dark-coloured skin.
Factors that may increase your risk of melanoma include:
Fair skin.
A history of sunburn.
Excessive ultraviolet (UV) light exposure.
Living closer to the equator or at a higher elevation.
Having many moles or unusual moles (dysplastic nevi).
A family history of melanoma.
Weakened immune system.
Basal cell carcinoma is a type of skin cancer that begins in the basal cells — a type of cell within the skin that produces new skin cells as old ones die off.
Most basal cell carcinomas are thought to be caused by?
Most basal cell carcinomas are thought to be caused by long-term exposure to ultraviolet (UV) radiation from sunlight
What is the most common presentation of basal cell carcinoma, and where does it most commonly occur?
Basal cell carcinoma often appears as a slightly transparent bump on the skin, though it can take other forms.
Basal cell carcinoma occurs most often on areas of the skin that are exposed to the sun, such as your head and neck.
Factors that increase your risk of basal cell carcinoma include:
Chronic sun exposure.
Severe sunburns.
Radiation therapy.
Fair skin.
Increasing age.
A personal or family history of skin cancer.
Immune-suppressing drugs.
Exposure to arsenic.
Inherited syndromes that cause skin cancer.
Complications of basal cell carcinoma can include:
A risk of recurrence.
An increased risk of other types of skin cancer.
Cancer that spreads beyond the skin. Very rarely, basal cell carcinoma can spread (metastasize) to nearby lymph nodes and other areas of the body, such as the bones and lungs.
This common form of skin cancer develops in the cells that make up the middle and outer layers of the skin.
Squamous cell carcinoma.
Squamous cell carcinoma of the skin most often occurs on sun-exposed skin, such as your scalp, the backs of your hands, your ears or your lips. But it can occur anywhere on your body, including inside your mouth, the bottoms of your feet and on your genitals.
Signs and symptoms of squamous cell carcinoma of the skin include:
A firm, red nodule
A flat sore with a scaly crust
A new sore or raised area on an old scar or ulcer
A rough, scaly patch on your lip that may evolve to an open sore
A red sore or rough patch inside your mouth
A red, raised patch or wartlike sore on or in the anus or on your genitals
Factors that may increase your risk of squamous cell carcinoma of the skin include:
Fair skin.
Excessive sun exposure.
Use of tanning beds.
A history of sunburns.
A personal history of precancerous skin lesions, such as actinic keratosis or Bowen’s disease.
A personal history of skin cancer.
Weakened immune system.
Rare genetic disorder. People with xeroderma pigmentosum, which causes an extreme sensitivity to sunlight, have a greatly increased risk of developing skin cancer.
A dome shaped, pearly tumour with telangectasias on the surface.
Basal cell carcinoma, squamous cell carcinoma, or malignant melanoma?
Nodular BCC.
A dome shaped, pearly tumour with telangiectasias, with central necrosis and erosion.
Basal cell carcinoma, squamous cell carcinoma, or malignant melanoma?
BCC.
What is the most common sun-exposed site for basal cell carcinoma?
The nose.
A smooth pearly nodule with telangiectasias and diffuse grey pigmentation.
Basal cell carcinoma, squamous cell carcinoma, or malignant melanoma?
Pigmented BCC.
If any suspicion that it may be MM, refer. The test says to biopsy, but Don said not to biopsy as this can accelerate MM.
Flat, less invasive lesions that tend to appear more on the trunk and extremities, often in multiples. Tends to appear earlier in life than other forms of this type of skin cancer. These circumscribed, round to oval, red, scaling plaques may be confused with eczema, psoriasis, extramammary Paget’s disease, or Bowen’s disease (SCC in situ).
Basal cell carcinoma, squamous cell carcinoma, or malignant melanoma?
Superficial BCC.
What is actinic keratosis?
Very common keratotic lesions with malignant potential. Most commonly found on sun-exposed areas of the elderly.
Usually consists of sharp yellow scale, can be tightly adherent to skin in early stages and develop a rough/sandpaper texture over time.
What estimated percentage of patients with actinic keratosis will develop squamous cell carcinoma in 1 or more lesions?
An estimated 20%
A full-thickness form of squamous cell carcinoma that is slow-growing and usually appears as a pink, scaly, well-demarcated patch.
Bowen’s disease.
A tumour on the lower lip most often indicates which form of skin cancer?
Squamous cell carcinoma.
The typical lesion has a pink to dull red, firm, poorly defined dome-shaped nodule with an adherent yellow-white scale.
Basal cell carcinoma, squamous cell carcinoma, or malignant melanoma?
SCC
30% of melanomas develop within a pre-existing ________.
Nevus.
Most melanomas that arise from a nevus tend to form superficial spreading melanoma - more common in white females.
What is acute paronychia
Bacterial infection of proximal and lateral nail fold, often called staph aureus
What kind of exudate is most common in bacterial infection?
Purulent exudate (has large number of leukocytes)
Differentiate gram positive from negative bacteria
Gram staining helps determine thickness of the wall to ID/ categorize bacteria. Crystal violet is the dye used. Peptidoglycans in the cell wall retain dye; a thick cell wall retains violet color; a thin does not.
Gram positive- stains purple or blue
Gram negative- stains pink or red
What bacteria are common pathogens in skin infections?
Staphylococcal, streptococcal pneumonia, cholera (mucous membranes), ?TB
T/ F bacteria is involved in the patho of acne vulgaris
True. In acne vulgaris, there are 4 causative factors:
1) hyperkeratinization of the follicular epithelium
2) excessive sebum production (caused by androgens and testosterone)
3) follicular proliferation of anerobic p. acnes
4) Inflammation and rupture of follicle from accumulated debris and bacteria
What is folliculitis?
Inflammation of hair follicle anywhere on body.
What is folliculitis caused by
Often staph aureus (most common) or pseudomonas (hot tub folliculitis). Can be fungal.
Patho of folliculitis
Bacterial infection spread by trauma/ itching/ shaving. Acneiform eruption becomes pustular, superficial. Leads to dome shaped pustules with small erythematous falos arising in a follicle. Can be tender.
Tx folliculitis
most respond to abx. minimize triggers like heat, friction, occlusion.
What are furuncles/ carbuncles?
Infected pocket/ abscess commonly caused by staph (localized redness) or strep (streaking). Furuncles are walled off masses and carbuncles are deep interconnected aggregates.
Most common bacteria causing furuncles/ carbuncles?
Staph (MRSA)
S&S/ dx of furuncles
-deep dermal or subcutaneous red, swollen, painful mass
-later points toward surface and drains through multiple openings
-afebrile
-gram stain, C&S indicated
S&S/ dx of carbuncles
-deep, tender, firm subcutaneous erythematous papules enlarge to deep seated nodules that can be stable or fluctuant within days
-often back of neck, upper back, lateral thighs
-malaise, fever, chills may precede or occur with height of inflammation
-gram stain, C&S indicated
Management of furuncles/ carbuncles?
-infection can spread to other sites
-recurrent furunculosis may be difficult to eradicate
-warm moist dressings
-incision and drainage are primary management for pointing, fluctuant lesions (refer to derm if on hands or face)
-systemic antibiotics if multiple lesions or signs of systemic illness (fever, malaise, spreading redness, increasing pain)
-Dicloaxacillin, cephalexin, clindamycin
-good handwashing will reduce # of & on skin. Use separate towels from others.
-follow up in 5-7 days to see if improving (2 days if using packing)
What is impetigo?
Superficial skin infection produced by streptococcus pyogenes, staph aureus, or both
Epidemiology of impetigo
Common (highly infectious), children have higher rates of infection (close physical contact), warm/moist/ humid climates and poor hygiene predispose
Time course impetigo
Self limited, but if untreated, may spread and last for weeks to months.
Signs and symptoms of impetigo
May occur after minor skin injury or within lesions of another dermatitis, however, often develops on normal skin.
Local or widespread; common on face.
Systemic symptoms infrequent.
Bullous- thin roofed bullae turn from clear to cloudy, collapse quickly leaving an inner tube shaped rim with central thin, fat, honey color stuck on crust. Lesions enlarge and coalesce. Minimal surrounding erythema. May have adenopathy
Non Bullous- vesicles or pustules rupture. Scaling border. Firm adherent crust is honey yellow to white brown; it accumulates.