Skin Pathology 1

Question 1

Which layer of the epidermis would you find anucleate, keratin-filled keratinocytes that protects against friction and water loss?

Answer 1

Stratum corneum

*Parakeratosis: keratinization with retained nuclei in the stratum corneum. Seen in Psoriasis.

• Hyperkeratosis: Anucleate cells in thickening of stratum corneum. Abnormality of keratin.

Question 2

Which layer of the epidermis have keratinocytes with distinct kerato-hyaline granules?

Answer 2

Stratum granulosum

*Contains Filaggrin
*Hypergranulosis: hyperplasia (thickening) of stratum granulosum

*Stratum granulosum is very thin or absent in Psoriasis

Question 3

Which layer of the epidermis have keratinocytes that are all joined by desmosomes (tonofibrils or keratin)?

*note that Langerhans cells are present in layer.

Answer 3

Stratum spinosum

Question 4

Which layer of the epidermis does mitosis occur?

*note: also contains melanocytes and Merkel cells

Answer 4

Stratum basale

*Attached to the basement membrane by hemidesmosomes and integrins

*As we age the activity of the stratum basale reduces causing epidermal atrophy (thinned out epidermis)

Question 5

Contraction of which muscle causes goosebumps?

Answer 5

Arrector pili muscle

Question 6

What gland am I?
sebum, sebocytes, holocrine secretion, pilosebaceous units, in the dermis

Answer 6

Sebaceous glands

*Holocrine secretion

Question 7

In which layer is melanin synthesized?

Answer 7

Stratum basale

*Attached to the basement membrane by hemidesmosomes and integrins

*As we age the activity of the stratum basale reduces causing epidermal atrophy (thinned out epidermis)

Question 8

In which layer filaggrin is found?

Answer 8

Stratum granulosum

*Contains Filaggrin
*Hypergranulosis: hyperplasia (thickening) of stratum granulosum

*Stratum granulosum is very thin or absent in Psoriasis

Question 9

What is the origin of melanocytes?

Answer 9

Neural crest cells

*Melanoma

Question 10

What is the origin for Langerhans cells?

Answer 10

Monocytes (erythromyeloid progenitor)

Question 11

What is the electron microscopic finding in Langerhans cells?

Answer 11

Birbeck granules

Question 12

Example of Merocrine

Answer 12

Salivary glands

Question 13

Example of holocrine

Answer 13

Sebaceous glands

Question 14

Example of apocrine

Answer 14

Mammary glands

Question 15

Scratch of the epidermis (causes a raw linear area)

Answer 15

Excoriation

Question 16

Thickened, rough skin with prominent markings, result of repeat rubbing

Answer 16

Lichenification

Question 17

Flat lesion, distinguished from surrounding color.
<5mm in diameter

Answer 17

Macule

Question 18

Flat lesion, distinguished from surrounding color.
>5mm in diameter

Answer 18

Patch

Question 19

Separation of nail plate from nail bed

Answer 19

Onycholysis

Question 20

Elevated, dome-shaped (or flat-topped) lesion
<5mm in diameter

Answer 20

Papule

Question 21

Elevated, dome-shaped (or flat-topped) lesion
>5mm in diameter

Answer 21

Nodule

Question 22

Elevated flat-topped lesion
>5mm across (may be caused by coalescent

Answer 22

Plaque