Lichenoid Eruptions

Question 1

what is a lichenoid eruption?

Answer 1

characterised by damage and infitration between the epidermis and dermis

Question 2

what are the types of lichenoid eruption?

Answer 2

lichen planus - most common 
lichenoid drug eruption 
discoid lupus 
erythema multiforme 
toxic epidermal necrolysis

Question 3

who gets lichen planus?

Answer 3

middle aged people

Question 4

how does lichen planus happen?

Answer 4

T-cell mediated infiltration within the skin and mucosal keratinocytes

Question 5

what is the histology of lichen planus?

Answer 5

irregular sawtooth ancanthosis
hypergranulosis
orthohyperkeratosis (hyperkeratosis without parakeratosis)

Question 6

how does lichen planus present?

Answer 6

PURPLE(Violaceous)
POLYGONAL
PRURITIC
PAPULES
PLANAR (Flat topped)
PLAQUES

usually on volar wrists/forearms, shins & ankles

Wickham’s striae - lace like pattern on the surface of the papules and the buccal mucosa
generally 12-18 months before it burns out

Question 7

in lichen planus how do you prevent the hyperpigmentation from becoming hypertrophic?

Answer 7

treat with topical/oral steroids

Question 8

how is lichen planus managed?

Answer 8

check if caused by a drug 
emollients 
treat symptomatically - topical or oral steroids depending on the extensity 
UVB phototherapy 
PUVA

Question 9

what is lupus?

Answer 9

a long-term autoimmune disase

Question 10

what are the cutaneous features of lupus?

Answer 10

subacute cutaneous/discoid lupus (affected by UV light exposure)
acute cutaneous lupus
non-scarring alopecia
oral ulceration
malar butterfly facial rash (classic lupus rash, may be provoked by UV light exposure)