Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Dermatology PPT 17 Lichen Planus Pityriasis Rosea Lecture Notes
Lichen Planus
&
Pityriasis Rosea
Lichen Planus
Leichen ? tree moss ; planus ? flat
Coined by Sir William James Erasmus Wilson in 1869
Idiopathic, inflammatory disorder affecting skin ,
mucous memb , nails & hair.
Chronic course with relapses and remissions
Affects 0.5% of the population
Age group affected: 30 ? 60 years
rare in children
ETIOLOGY :
1. Idiopathic
2. Familial associations: HLAA3, A5, B7, DR1 and
DRB*0101.
3. Drugs causing LP like eruptions ? gold salts, beta blockers,
antimalarials, thiazides, furosemide, spironolactone, penicil amine
4. Dental amalgams
5. Infections ? HCV
6. Betel leaf, areca nut use in South East Asia - oral LP
PATHOGENESIS
The exact pathomechanisms are unclear
Autoimmunity is clearly suggested to be central in
pathogenesis in LP
1. LP ? specific antigen recognition
2. Cytotoxic Lymphocyte Activation
3. Keratinocyte Apoptosis
CLINICAL FEATURES
firm, shiny, polygonal, 1?3 mm diameter papules, red to
violet
6 P's --- purple, pruritic, polygonal, plane topped,
papules, plaques
Pruritus: mild irritation, to continuous severe itching
interfering with sleep
distribution: isolated/grouped, linear/annular
resolved lesions: greyish brown due to
deposition of melanin in the superficial dermis.
Sites : volar aspect of the wrists, lumbar region,
ankles, shins, scalp, palms, soles.
Oral and genital mucosa
- WICKHAM'S STRIAE :on
BROCQ'S
close inspection a trace of
PHENOMENON:
thin white lines seen on
Subepidermal
the surface of the lesions
hemorrhage
following scraping
of a classical LP
lesion
KOEBNER'S PHENOMENON
Development of
lesions in
previously normal
skin that has been
subjected to trauma
HISTOPATHOLOGY
TYPES OF LP
MORPHOLOGY
SITE
SPECIAL
HYPERTROPHIC
SKIN
ACTINIC
ATROPHIC
MUCOSAL
LP
(ORAL, GENITAL)
PEMPHIGOIDES
GUTTATE( ERUPTIVE)
PALMOPLANTAR
LP PIGMENTOSUS
ANNULAR
NAIL
LINEAR
SCALP
VESICULOBULLOUS
INVERSE
FOLLICULAR
ULCERATIVE/EROSIVE
HYPERTROPHIC LP
Hypertrophic or warty
lesions
Lower limbs, especially
around the ankles
Severely itchy
Must be distinguished
from lichen simplex
chronicus and lichen
amyloidosis
GUTTATE LP
Lesions are widely
scattered, discrete, size
(1?2 mm)
Differentiate from
guttate psoriasis
ANNULAR LP
very narrow rim of
activity with a
depressed, slightly
atrophic centre
characteristically found
on the penis
BULLOUS LP
blisters arise only on or
near the lesions of LP
short duration
HPE - severe liquefaction
degeneration of the basal
cell layer. Subepidermal
bulla with typical changes
of LP
direct and indirect
immunofluorescence
negative.
FOLLICULAR LP
Follicular lesions
Scalp
Intensely itchy
scarring alopecia
ACTINIC LP
Lichen planus
subtropicus ?
dark skinned, tropical
countries
welldefined
annular/discoid patches,
with a deeply
hyperpigmented centre &
surrounded by a striking
hypopigmented zone
Sunexposure :central to
the pathogenesis
LICHEN PLANUS PIGMENTOSUS
India, Middle East
macular
hyperpigmentation:
slate grey to
brownish black
face, neck and
upper limbs
LICHEN PLANUS PEMPHIGOIDES
acute and generalized
large bullae on both involved
and uninvolved skin.
HPE: subepidermal bulla
without evidence of LP
Direct IF: linear deposition of
IgG, C3 along basement
membrane zone in
perilesional skin
Immunoelectron
microscopy: deposition of
IgG,C3 in the base of the
bulla (unlike BP- roof )
LICHEN PLANUS: PALMS, SOLES
lesions are firm, rough
with a yellowish hue
broadly sheeted or
punctate
diagnosis is very
difficult; syphilis,
psoriasis, callosities
and warts must be
excluded
MUCOSAL LESIONS
Seen in 30?70% cases; may be isolated
Sites:
buccal mucosa,
tongue (most often involved)
genitalia- the penile shaft, glans penis, prepuce,
scrotum, vulva
perianal
Patterns Of Mucosal Involvement
? Reticulate ? most common
? Atrophic
? Hypertrophic
? Erosive/Ulcerative
? Plaque-like
? Papular
? Bullous
ORAL LP
Reticulate
pattern(M/C)
White streaks, often
forming a lacework.
inner surface of the
cheeks, gum
margins, lips.
Associated oral
candidiasis
VULVAL LP
welldemarcated
erosions/erythematous areas at
the vaginal introitus
hyperkeratotic border of lesions;
Wickham's striae in the
surrounding skin
vaginal inflammation
pain/burning, scarring/loss of
normal architecture
involvement of other mucosa
NAIL INVOLVEMENT
10% cases. Fingernails > toenails
initially 2/3 fingernails, subsequently remaining
digits.
Exaggerated longitudinal lines, linear depressions
Adhesion between the epidermis of the dorsal
nail fold and the nail bed: pterygium unguis
complete shedding
Exaggerated
Pterygium unguis
longitudinal lines
PROGNOSIS / COMPLICATIONS
Lesions resolve with pigmentation that may last for
many months
Recurrent episodes
Oral & hypertrophic lesions may be premalignant
Scarring alopecia
TREATMENT of LP
:
TOPICAL
PHOTOTHERAPY
SYSTEMIC
TCS
PUVA
STEROIDS
IMMUNOMODULATORS
RETINOIDS
TRETINOIN
STEROID SPARING
(ORAL LESION)
DRUGS
LIDOCAINE(ORAL
TETRACYCLINES
LESION)
VIT.D ANALOGUES
DAPSONE
METRONIDAZOLE
GRISEOFULVIN
THALIDOMIDE
BIOLOGICALS
TREATMENT LADDER:
CUTANEOUS
First line
Limited: very potent corticosteroids topical (eg.clobetasol
propionate ointment 0.05%);
Widespread: systemic prednisolone 0.5?1 mg/kg per day
until improvement
Second line
Prednisolone 0.5?1 mg/kg per day until improvement
Acitretin 30 mg per day for 8 weeks
PUVA /UVB: two to three times a week ? systemic
retinoids
TREATMENT LADDER: ORAL
First line
Symptomatic : very potent corticosteroids
Soluble prednisolone tablets, 5 mg in 15 mL water, mouthwash tds or
betamethasone soluble tablets 0.5 mg
Severe erosive LP: prednisolone 0.5?1 mg/kg per day
Second line
Papular ,plaquelike white forms no erosions: topical retinoids
Resistant to topicals: prednisolone 0.5?1 mg/kg
Third line
Steroid dependent/resistant erosive LP: Azathiprine, MMF, Mtx,
Cyclosporin A
TREATMENT LADDER: NAILS
< four nails
superpotent corticosteroids
Severe nail involvement :
monthly intralesional injection of triamcinolone acetonide (0.5
?10 mg/mL) in the periungual sites.
oral prednisolone (0.5?1 mg/kg/day)
LICHEN NITIDUS
pinpoint to pinheadsized
papules,
flesh coloured, with a flat,
shiny surface. Remain
discrete
asymptomatic
forearms, penis, abdomen,
chest, buttocks.
selflimiting, no treatment
intense, circumscribed,
infiltrate of lymphocytes,
histiocytes & few Langhans
cells situated immediately
below a flattened epidermis.
The rete ridges at the margin
of the infiltrate are elongated
to encircle it
liquefaction degeneration of
the basal cell layer.
PITYRIASIS ROSEA
Pityriasis ? scales ; Rosea ? pink ( Gilbert )
Acute , self-limiting disease , probably
infective in origin.
Children & young adults with a slight female
preponderence.
Minimal symptoms - pruritus
ETIOLOGY:
1. Viral : HHV 7 ; HHV 6 ? reactivation
2. Drugs : Metals ( Ar, Bi, Au)
Lithium
Methopromazine
Metronidazole
Barbiturates
Clonidine
Captopril etc.
CLINICAL FEATURES
HERALD PATCH
primary plaque/mother
patch.
Sharply defined
erythematous annular
plaque with a peripheral
col arette of scales.
M/C Site ? thigh,upper
arm,trunk or neck
Within 5-15 days
Generalised eruption
? discrete oval
lesions similar to the
herald patch but
smaller in size
Upper chest & back ? Christmas /Inverted Fir
tree pattern.
Face,scalp ? children
Palms ? rare, scaly red plaques / diffuse
redness / /small vesicles.
Oral ? ill defined red patches
Atypical / Morphological Variants:
papules / vesicles / papulovesicular
urticarial
erythema multiforme like
pustular
purpuric
lichenoid
exfoliative dermatitis
Epidermis ? patchy parakeratosis, spongiosis.
Dermis (upper) ? edema , mononuclear cel infiltrate ( exocytosis into
epidermis forming subcorneal pustules.
TREATMENT :
Acyclovir ( 800mg 5 times a day x 1 week)
Erythromycin (500mg qid x 2 weeks- adult
40mg/kg div.doses ? child)
Oral antihistamines
Topical steroids- mid potent
Topical antipruritic lotions
UVB.
THANKYOU
This post was last modified on 07 April 2022