Descriptive Dermatopathology

Question 1

Hyperkeratosis

Answer 1

Thickening of the epidermis with thickening of the stratum corneum. Epidermal differentiation of keratinocytes is normal. Compacted cells with loss of normal basket weave pattern (compact hyperkeratosis, compact orthohyperkeratosis).

Question 2

Hyperkeratosis

Answer 2

Thickening of the epidermis with thickening of the stratum corneum. Epidermal differentiation of keratinocytes is normal. Compacted cells with loss of normal basket weave pattern (compact hyperkeratosis, compact orthohyperkeratosis).

Question 3

Parakeratosis

Answer 3

Nuclei are retained within the stratum corneum. Parakeratosis indicates that the epidermis is inflamed or injured.

Question 4

Acanthosis

Answer 4

Thickening of the epidermis and elongation of the rete ridges due to thickening of the spinous layer. May be associated with enlargement of rete pegs.
- thickened squamous cell layer (epidermal change)

Question 5

Erosion

Answer 5

loss of a portion of the epidermis

Question 6

Ulcer

Answer 6

loss of the entire epidermis

Question 7

Acantholysis

Answer 7

The keratinocytes are seen ‘floating apart’ from each other because of loss of desmosome cell connections. Cells take a rounded shape. Different conditions have unique patterns of acantholysis, for example, in pemphigus vulgaris, the acantholysis is just above the basal layer of the epidermis (suprabasilar acantholysis or suprabasilar clefting) but the basal layer remains intact (tombstone appearance). In contrast, in pemphigus foliaceus, the acantholysis is higher up, just below the stratum corneum.

Question 8

Spongiosis

Answer 8

Spaces between keratinocytes are more apparent than normal. The spaces are filled with leaked tissue fluid (edema). Indicates that the epidermis is inflamed. Most commonly seen in eczema but can be seen incidentally or as part of other skin conditions. If severe, visible blisters may occur because the keratinocytes are not sticking together firmly.

Question 9

Vesicle

Answer 9

Small fluid-filled blister(s) within or below the epidermis.

Question 10

Atrophy

Answer 10

Thinning of the dermal layer due to loss of collagen

Question 11

Sclerosis

Answer 11

A hardening or induration of a tissue, or an increase of connective tissue or the like at the expense of more active tissue.
- hyalinized collagen in the dermal layer

Question 12

Parakeratosis

Answer 12

Nuclei are retained within the stratum corneum. Parakeratosis indicates that the epidermis is inflamed or injured.

Question 13

Acanthosis

Answer 13

Thickening of the epidermis and elongation of the rete ridges due to thickening of the spinous layer. May be associated with enlargement of rete pegs.
- thickened squamous cell layer (epidermal change)

Question 14

Erosion

Answer 14

loss of a portion of the epidermis

Question 15

Ulcer

Answer 15

loss of the entire epidermis

Question 16

Acantholysis

Answer 16

The keratinocytes are seen ‘floating apart’ from each other because of loss of desmosome cell connections. Cells take a rounded shape. Different conditions have unique patterns of acantholysis, for example, in pemphigus vulgaris, the acantholysis is just above the basal layer of the epidermis (suprabasilar acantholysis or suprabasilar clefting) but the basal layer remains intact (tombstone appearance). In contrast, in pemphigus foliaceus, the acantholysis is higher up, just below the stratum corneum.

Question 17

Spongiosis

Answer 17

Spaces between keratinocytes are more apparent than normal. The spaces are filled with leaked tissue fluid (edema). Indicates that the epidermis is inflamed. Most commonly seen in eczema but can be seen incidentally or as part of other skin conditions. If severe, visible blisters may occur because the keratinocytes are not sticking together firmly.

Question 18

Vesicle

Answer 18

Small fluid-filled blister(s) within or below the epidermis.

Question 19

Atrophy

Answer 19

Thinning of the dermal layer due to loss of collagen

Question 20

Sclerosis

Answer 20

A hardening or induration of a tissue, or an increase of connective tissue or the like at the expense of more active tissue.
- hyalinized collagen in the dermal layer