Clinical Skin Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Parakeratosis

A
  • pathological
  • Thickened keratin layer
  • Keratins contains spindly nuclear remnants
  • usually associated with loss or severe thinning of underlying granular layer
  • may be associated with epidermal dysplasia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hyperkeratosis

A
  • (non-pathological)
  • present in elbow & soles
  • thickened keratin layer
  • no histological abnormality in keratin layer
  • usually associated with thickening of underlying granular layer - hypergranulosis
  • seen in cases of chronic trauma like scratching
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Pemphigus vulgaris

A
  • blistering disorder
  • auto-AB that result in dissolution of intercell attachments (desmosomes) w/in epidermis & mucosal epithelium
  • Clinical presentation:
    • superficial blisters & bullae that rupture easily
    • ulcerated blisters in oral mucosa are also common
  • Light microscope shows:
    • tombstone blister
    • Acantholysis: disruption of intercell adhesions in cells immediately above basal layer in stratum spinosum
    • suprabasal blister
    • acantholytic cells: rounded & lose symmetry
    • fish-net patter of Ig deposition along plasma membrane of epidermal keratinocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Bullous pemphigoid

A
  • chronic autoimmune disorder
  • bullous pemphigoid antigens 1 & 2 present as nl constituents of hemidesmosomes -> auto-ab bind to antigens & stimulate complement deposition & leucocyte infiltration -> degrading eosinophils release proteases that degrade hemidesmosomes
  • Rx: topical Corticosteroid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Acne vulgaris

A
  • occurs almost universally in middle to late teenage years
  • hormonal variations & alterations in hair follicles, particularly in sebaceous glands
  • Open Comedone (black head): small follicular papules with central keratin plug
  • Severe acne: papules, nodules, cysts
  • Light microscope:
    • development of keratin plug blocking outflow of sebum
    • hypertrophy of sebaceous gland
    • infection with cane causing bacteria Propionobacter acnes
    • inflammation of follicle
  • Rx: Vitamin A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Vitiligo

A
  • depigmentation disorder
  • auto-immune
  • destruction of melanocytes
  • Types: focal, segmental, generalized
  • Rx:
    • Medical: topical steroid therapy, psolaren photochemotherapy (increases pigmentation), depigmentation
    • surgical: autologous skin graft, micropigmentation, melanocyte transplants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Psoriasis

A
  • due to increased rate of proliferation of mitotic cells, thereby leading thickened epidermis
  • leads to shedding of epidermis constantly, resulting in scales seen as whitish patches, especially in extensor aspects of limbs, trunk & lumbosacral region
  • autoimmune T-cells (cytokines & cell-mediated autoimmunity)
  • increased epidermal turnover (3-5 d); marked epidermal thickening and increase in size of epidermal ridges
  • abnormal keratinocyte differentiation: loss of S. granulosum
  • parakeratosis: S. corneum thickening & nuclei retention
  • weak junctional complexes in superficial layer (silvery scales)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Basal Cell Carcinoma

A
  • most common invasive cancer in humans
  • arises from basal cells of epidermis or epidermal appendages
  • tendency to occur in sun-exposed areas and in lightly pigmented people
    • pearly papules
    • contain prominent, dilated sub-epidermal blood vessels
    • rolled out margins
    • advanced lesions may ulcerate with extensive local invasion (rodent ulcers)
  • nest of uniformly atypical basaloid cells within the dermis (basophilic)
  • separated from adjacent stroma by thin clefts
  • basophilic cells with dark staining nuclei and sparse cytoplasm
  • cells at the periphery tend to be arranged radially with their long axes in parallel arrangement (pallisade arrangement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Squamous Cell Carcinoma

A
  • 2nd most common tumour arising in sun exposed sites
  • higher incidence in men than women
  • DNA damage induced by exposure to UV light
  • p53 mutations
  • commonly associated with chronic immunosuppression: chemotherapy or organ transplant
  • increased susceptibility of keratinocytes to infection and transformation by oncogenic viruses
  • other risk factors
    • industrial carcinogens like tars & oils
    • chronic ulcers
  • light microscopy shows:
    • nodular & ulcerated lesions
      • well differentiated
      • highly keratising
      • larger than nl cells
      • nuclear pleomorphism: keratin pearls
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Malignant Melanoma

A
  • malignant transformation of melanocytes
  • most common on sun exposed surfaces
  • lightly pigmented individuals are at higher risk
  • important pre-disposing factors:
    • inherited genes: mutations in RB tumour supressor gene
    • sun exposure
  • clinical features:
    • usually asymptomatic so frequently undetected; very dangerous
    • itching or pain may occur
    • changes in colour, size or shape of a pigmented lesion most important clinical indicator
      • A: assymetry
      • B: borders (irregular)
      • C: colour (variegated)
      • D: diameters (>6mm)
      • E: elevated lesion
    • Light microscopy shows:
      • ayptical melanocytes in epidermis & dermis with large nuclei & prominent nucleoli
      • radial growth: horizontal spread of melanoma within epidermis
      • vertical growth: tumour cells invade deeper layers
      • metastases may occur: usually fatal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Neurofibromatosis (Von Reclinghausens Disease)

A
  • not a skin lesion
  • nerve-ending lesions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly