1.1 Elementary phenomena on the skin. Flashcards
1
Q
What are primary lesions?
A
- lesions that are a diret result of the disease
- macules, papules, plaques, patches, nodules, tubers, pustules, wheals, bullas, vesicles, cysts
2
Q
What are secondary lesions?
A
- lesions developing from a primary lesion or due to patient activities
- erosions, ulcers, excoriations, fissures, crusts, scales, fistulas, lichenification, atrophy, scars
3
Q
What are macules?
A
- hypopigmented/hyperpigmented skin lesion that is non-palpable (has no elevation)
- <1cm (>1cm = patch)
4
Q
What are exogenous pigments that cause macules?
A
- tattoo dyes
- gunpowder
- carotene
5
Q
What are endogenous pigments that cause macules?
A
- melanin
- lipofuscin
- hemoglobin
- bilirubin
6
Q
What are examples of macules?
A
- Morphea: localized scleroderma; vessels get compressed due to increased keratin production resulting in improper melanin delivery
- lentigo senilis: lipofuschin brown spots commonly on the face due to sun exposure
- vitiligo segmentalis: immune system destroys melanocytes resulting in hypopigmentation
- subungual melanoma: melanin seen
7
Q
What are papules?
A
- cellular infiltration in the papillary dermis (epidermis)
- always palpable (elevated), <1cm
- inflammatory/tumorous
- popular examthema is a rash consisting of papules
8
Q
What are examples of papules?
A
- psoriasis guttate: non-contagious autoimmune disease, usually triggered by bacterial infection
- pigmented nevi: (aka mole) due to local proliferation of melanocytes
- lichen ruber planus: autoimmune disease against keratinocytes
9
Q
What are plaques?
A
- cellular infiltration of the papillary dermis
- always palpable (elevated), >1cm diameter
- erythroderma: affects the entire body surface
- group of papules together
10
Q
What are some examples of plaques?
A
- psoriasis vulgaris
- erythema chronicum (ie. borreliosis)
11
Q
What are nodules?
A
- cellular infiltration in the reticular dermis and subcutis
- usually >2cm
- usually not elevated but is palpable
- not spherically shaped
12
Q
What are examples of nodules?
A
- erythema nodosum
- lupus panniculitis
13
Q
What is tuber?
A
- cellular infiltration in the reticular dermis and subcutis
- spherically shaped, highly elevated lesions that are firm upon palpations
- frequent caseation, ulceration and scarring
- ie. cutaneous tuberculosis
14
Q
What is gumma?
A
like tuber but seen in tertiary syphilis
15
Q
What is a tumor?
A
- tumor cell infiltration in any layer of the skin
- ie. malignant melanoma, basal cell carcinoma
16
Q
What is urticaria?
A
- circumscribed edema of the dermis
- can be erythematous due to vessel dilation
- may be due to an allergic reaction or an acute infection
- characteristically disappears within 24 hours
- ie. urticaria factitia, cold urticaria
17
Q
What is a vesicle?
A
- cavity of <0.5cm within or below the epidermis, filled with serous/hemorrhagic fluid
- usually elevated
- no epithelial wall
18
Q
What are examples of vesicles?
A
- herpes labialis
- dermatitis
- acute contact dermatitis
- herpetiformis
- hand-foot-mouth disease
19
Q
What is a bulla/blister?
A
- > 0.5 cm
- circumscribed fluid-filled lesion
- ie. pemphigus vulgaris, bullous pemphigoid
20
Q
What is a pustule?
A
- like a vesicle/bulla but filled with pus and can be found on any layer of skin
- usually elevated
- yellow color due to WBC’s
- not always due to infections
21
Q
What are examples of pustules?
A
- acne vulgaris
- furuncle
- pustular psoriasis
22
Q
What is a cyst?
A
- cavity (closed sac) in the skin that contains air or serous, pus or hemorrhagic fluid or semi-solid material like sebum
- covered by an epithelial wall
- often due to blockage of sebaceous glad duct leading to sebum buildup and then rupture/inflammation
- ie. epidermal cyst
23
Q
What is an ulcer?
A
- lack of layers of skin due to necrosis
- units under the skin are visible
- necrosis of tuber/gumma/tumor
- ie. diabetic leg ulcer
24
Q
What is erosion?
A
- due to ruptured vesicle/blister or physical abrasions
- superficial denudation of the epidermis: sharply defined, erythematous, often oozing serum
25
Q
What are examples of erosion?
A
- bullous pemphigoid
- pemphigus vulgaris
- contagious impetigo
26
Q
What is excoriation?
A
erosion or ulcer due to patient scratching
27
Q
What is a fissure?
A
- vertical cleft in the skin, extending into the dermis
- usually develops from chronic plaques
- develops spontaneously; surgical wounds are not fissures
28
Q
What is atrophy?
A
- partial or complete wasting away (shrinking, involution, incomplete development) of the skin
- commonly seen due to aging or corticosteroid therapy
- ie. steroid atrophy, scar
29
Q
What is a fistula?
A
- abnormal connection between hollow spaces
- “little tunnel”
30
Q
What is scaling?
A
- peeling, desquamation
- shedding of the outermost layer of the skin
- ie. psoriasis vulgaris, pityriasis, solar dermatitis
31
Q
What is lichenification?
A
- an increase in the skin lines, wrinkles and creases from chronic inflammation and rubbing
- ie. atopic dermatitis, chronic contact dermatitis
32
Q
What is a scar?
A
- aka cicatrix
- fibrous degeneration tissue due to wound repair in the skin, replacing normal skin after injury of the dermis and/or subcutis
- common after healing of ulcer, excoriation and fissure (but NOT after erosion)
- ie. surgical wound, keloid
