1 - pathology of rashes

Question 1

what are layers of epidermis?

Answer 1

1. keratin (stratum corneum) = tough outer layer of corneocytes & keratinocytes
2. granular layer = keratohyalin granules
3. prickle cell layer = langerhan cells and prominent desmosomes
4. basal layer = small cuboidal

Question 2

what are layers of dermis?

Answer 2

1. papillary dermis (thin, just beneath epithelium)
2. reticular dermis (thicker, type I collagen, also where appendages are)

Question 3

what is hyperkeratosis?

Answer 3

increased thickness of keratin layer

Question 4

what is parakeratosis?

Answer 4

persistence of nuclei in keratin

Question 5

what is acanthosis?

Answer 5

increased thickness of epithelium

Question 6

what is papillomatosis?

Answer 6

irregular epithelium thickening

Question 7

what is spongiosis?

Answer 7

oedema fluid in between squamous layers

Question 8

what are 4 main reaction patterns to inflammatory skin disorders?

Answer 8

1. spongiotic (oedema) e.g. eczema
2. psoriasiform (elongation rete ridges - wavy lines separating dermis & epidermis) e.g. psoriasis
3. lichenoid- basal layer damage (lymphocytes damage epithelium) e.g. lichen planus or lupus
4. vesiculobullous e.g. pemphigoid, pemphigus & dermatitis herpetiformis