Verruca

Question 1

What are verruca warts caused by?

Answer 1

HPV

Question 2

what kind of virus is HPV?

Answer 2

ds DNA virus surrounded by an icosohedral (has 20 sides) capsule

Question 3

HPV warts are very persistent, what is this attributed to?

Answer 3

lack of Langerhans cells at site of lesion, leading to decreased T-cell response

Question 4

what type of environment does HPV thrive in to promote infection/

Answer 4

pH of 5 (seen in swimming pools)

Question 5

do warts have an incubation period? if so, for how long?

Answer 5

4-20 months

Question 6

verruca warts invade which layer of the skin?

Answer 6

purely epidermal in its histopathology

does not extend into the dermis

Question 7

what are the 3 pathognomonic characteristics of verruca warts?

Answer 7

• acanthosis
• hyperkeratosis
• papillomatosis

Question 8

what is acanthosis?

Answer 8

thickening of stratum spinosum

Question 9

what is hyperkeratosis?

Answer 9

thickening of stratum corneum

Question 10

what is papillomatosis?

Answer 10

upward proliferation of epidermal papillae causing surface of epidermis to show irregular undulation

Question 11

in which layer does DNA and protein production occur?

Answer 11

stratum spinosum

Question 12

in which layer does final virus assembly occur?

Answer 12

granular layer

Question 13

what are the black dots or petechiae that are seen clinically within the white fibrotic base of the wart due to?

Answer 13

papillomatosis

Question 14

what are the 3 most common forms of HPV causing plantar warts in humans?

Answer 14

HPV 1 (common wart)
HPV 2 (mosaic wart)
HPV 4 (common wart)
HPV 10 
HPV 63- has also been implicated

Question 15

how can you differentiate between a wart and IPK?

Answer 15

wart will hurt with side-to-side compression whereas an IPK will hurt more on direct compression

Question 16

where are IPK’s found? how about in comparison to warts? or porokeratosis?

Answer 16

IPK- found on WB areas

warts & porokeratosis - found anywhere on plantar surface

Question 17

for some verruca, you worry about it undergoing transformation to what?

Answer 17

squamous cell CA

Question 18

What is the MOA for topical salicylic acid?

Answer 18

keratolytic agent- hastens de-squamation of the skin

Question 19

What is the MOA of Cantharidin?

Answer 19

is applied under occlusion and causes a severe blister

Question 20

What is the MOA of liquid nitrogen (cryosurgery)?

Answer 20

cell death occurs below -20C

Question 21

What is the MOA of liquid nitrogen (cryosurgery)?

Answer 21

cell death occurs below -20C

Question 22

what is the MOA of topical steroids?

Answer 22

under occlusion, it inhibits cell division and synthesis of DNA in epidermis

Question 23

what is the MOA of tretinoin (topical Vitamin A)?

Answer 23

increases differentiation and proliferation of epidermis

Question 24

what is the MOA of 5-FU?

Answer 24

inhibits DNA synthesis

Question 25

what is systemic etretinate (Soriatane) MOA?

Answer 25

systemic retinoid for psoriasis but can be taken orally to clear warts

Question 26

what is MOA of Tagamet (cimetidine) ?

Answer 26

interferes with suppressor T-cell function, so inflammatory response against virus is prolonged

Question 27

what is MOA of 0.1% bleomycin ?

Answer 27

(intralesional injection therapy) - inhibits DNA synthesis

Question 28

what is the theory behind immunotherapy for treating verruca?

Answer 28

theory is to induce a delayed cutaneous hypersensitivity reaction against the wart

Question 29

what is MOA of 3% topical SADBE?

Answer 29

induces a delayed hypersensitivity reaction

Question 30

what is the MOA of Imiquimod (Aldara) cream?

Answer 30

-recruits cytokines and IFN-alpha to induce keratinocytes to produce enzymes to block viral replication

Question 31

what is the needling technique?

Answer 31

needle is inserted repeatedly into the wart, and works by destruction of tissue and induction of inflammatory response

Question 32

what is curettage technique?

Answer 32

-margin of wart bluntly dissected with tissue nipper

Question 33

what is hyfrecation?

Answer 33

electrodessication that uses spark-gap technology and causes tissue dehydration --> cell death ensues with thrombosis of blood vessels

Question 34

light passed thru a CO2 gas chamber is absorbed by what?

Answer 34

water --> so any tissue that absorbs this will become fried

Question 35

light passed thru a chamber of dye is absorbed by what?

Answer 35

red pigment --> causes thrombosis of vessels