Psoriasiform reaction pattern

Psoriasiform dermatitis
Nathan C. Walk, M.D.
Interpretation of inflammatory skin biopsies:
– Identifyy and integrate
g
2 morphological
p
g
features
Tissue reaction pattern
– Distinctive morphologic patterns that allow grouping diseases
– Majority of inflammatory dermatoses can be categorized into
six different patterns
Lichenoid
Psoriasiform
Spongiotic
Vesiculobullous
Granulomatous
Vasculopathic
Pattern of inflammation
Psoriasiform reaction pattern
*Psoriasis
AIDS--associated psoriasiform dermatitis
AIDS
*Pustular psoriasis
*Reiter’s syndrome
– Histology indistinguishable from pustular psoriasis
*Pityriasis rubra pilaris
*Parapsoriasis
– Small p
plaque
q = chronic superficial
p
dermatitis
– Large plaque = pre MF
*Lichen simplex chronicus
The psoriasiform reaction pattern -- Other
*Subacute and chronic spongiotic dermatitides
Erythroderma
Mycosis fungoides
Chronic candidiasis and dermatophytoses
Inflammatory linear verrucous epidermal nevus
Norwegian scabies
Bowen’s disease
Clear cell acanthoma
Lamellar ichthyosis
y
Pityriasis rosea (herald patch)
Pellagra
Acrodermatitis enteropathica
Glucagonoma syndrome
Secondary syphilis
Always reference normal…
normal
Cases 1 & 2
Psoriasis
2% p
population
p
All racial groups
Mean age 25, 2 peaks – 20
20--30, 40
40--60; less
severe if develops in elderly
Children – most common is guttate form
Strong genetic factors
factors…HLA
HLA Cw6 confers RR 13
in Caucasians
– Identical twin studies….
Triggers: trauma (Koebbner), infection, drugs,
HIV
Psoriasis
Clinical ((Bolognia):
g )
– Basically - erythema,
thickened skin, and scale
– Sharply
p y demarcated
papules and/or plaques,
depending on variant
– Auspitz sign – remove
scale
l and
d gett bl
blood
d
– Extensor surfaces of
extremities, elbows, knees,
sacral region
region, scalp
scalp, nails
– Oral lesions rare
– Often pruritic, esp during
exacerbation
Psoriasis
Histology:
– Varies
V i d
depending
di on age off
lesion.
– Vascular dilation, spongiosis,
mounds of parakeratosis,
exocytosis of neutrophils into
parakeratosis
– **Loss of granular layer
– Acanthosis - regular
– PVLI – usually not many
neutrophils here
– With time…confluent
parakeratosis, Munro
microabscesses
i
b
(PMN
(PMNs iin s.
corneum), pustules of Kogoj
(s. spinosum)
– Psoriasiform hyperplasia
(regular acanthosis) and thin
suprapapillary plates
Clinical Differential ((Bolognia):
g )
–
–
–
–
–
LSC
Seborrheic dermatitis
SCCIS
CTCL
Hypertrophic LP – when on shins…psoriasis w/ scalp,
intergluteal
g
fold involvement
– With erythroderma: Sezary Sx, PRP, drug.
– With g
guttate form: small p
plaque
q p
parapsoriasis,
p
, PLC,, secondary
y
syphilis, PR, tinea
– With pustules: AGEP (drug), tinea, SneddonSneddon-Wilkinson
Pustular psoriasis
p
– Intraepidermal pustules at various stages of development.
– Early, epidermis only slightly acanthotic.
– Psoriasiform hyperplasia
yp p
seen only
y in older,, p
persistent lesions.
Reiter’s syndrome
– Triad: non
non--gonoccocal urethritis, arthritis, uveitis
– Mucocutaneous lesions – a 4th feature!
– Indistinguishable histology from Pustular psoriasis
G tt t psoriasis
Guttate
i i
– Guttate form – changes milder…like evolving lesion,
parakeratosis a/w loss of granular layer is limited to small foci
Guttate psoriasis
p
Cases 3 & 4
Pityriasis rubra pilaris
Clinical:
– Follicular hyperkeratosis on
erythematous base is KEY
– Results in rough papules
that coalesce to form large
red to orangeorange-red plaques
with distinctive “islands of
sparing”
– May become erythrodermic
– Orange
Orange--red waxy
keratoderma of palms and
soles
– Scalp, nail involvement
– Usually begins in H/N (may
look like seb derm) and
progresses caudally –
acute disorder
– Pruritus/burning 20%
Pityriasis rubra pilaris
Histology:
– Biopsy @ site of erythema,
not plugs….
plugs
– Parakeratosis at lips of
follicles, follicular plugging
– Alternating orthokeratosis and
parakeratosis in both vertical
and horizontal directions
– Irregular acanthosis
– Irregular HYPERKERATOSIS
– THICK suprapapillary plates
– RETAINS g
granular layer,
y , mayy
be hypergranulosis
– SPLI
– May have focal acantholytic
dyskeratosis**
Clinical Differential:
– Usually easily recognized
– Psoriasis – family hx, nail involvement, no
islands of sparing
sparing, not follicular based
– Seborrheic dermatitis – may mimic early PRP
– Kawasaki’s
Kawasaki s disease – if child with acute onset
Case 5
Necrolytic migratory erythema
Glucagonoma syndrome
– Necrolytic migratory erythema
– Glossitis
– Stomatitis
– Glucose intolerance
– Anemia
– Weight
g loss
– a/w islet cell tumor of pancreas
Necrolytic migratory erythema
Clinical:
– Waves of extending
annular erythema and
superficial epidermal
necrosis.
– Shedding of skin leading to
flaccid bullae and crusted
erosions.
– Resolution within 10
10--14
days.
days
– Primarily affect trunk, groin,
perineum, thighs and
buttocks.
buttocks
Necrolytic migratory erythema
Pale,, vacuolated
keratinocytes in the upper
epidermis, leading to
focal and eventual
confluent necrosis.
– “necrolysis”
Psoriasiform hyperplasia
with overlying confluent
parakeratosis vascular
parakeratosis,
dilatation.
PVLI
Case 6
Lichen simplex chronicus
Persistent rubbing
Atopy, other reason?
Clinical:
– Almost never in children;;
>60
– Hyperpigmented,
lichenified, leathery
plaques
– Well circumscribed
– Predilection for the occipital
and nuchal areas in
women; perineum,
i
scrotum
t
in men
– Other favored areas
include wrists,, extensor
surfaces of forearms, and
lower legs
Lichen simplex chronicus
Histology:
– Thick, compact orthokeratosis
– like acral skin
– Hypergranulosis
– ***?parakeratosis
?parakeratosis
– Psoriasiform hyperplasia with
thick rete of less even length
g
than psoriasis
– Epidermal thickness and
volume greater than in
psoriasis
– Thick papillary dermis with
vertical collagen
– Inflammation
Case 7
Prurigo nodularis
Clinical:
– Numerous persistent,
intensely pruritic nodules.
– Involve predominantly
extensor aspects of the
limbs, symmetrically.
– Range from few in number
to >100
>100.kk
– ?underlying cause for
pruritus
Metabolic disorder
Arthropod bites
Folliculitis
Atopy
py
Prurigo nodularis
Histology:
– Prominent
hyperkeratosis, focal
parakeratosis
– Marked irregular
acanthosis
– Tends to be
folliculocentric
– Pseudoepitheliomatous
hyperplasia
Case 8
Seborrheic dermatitis
Clinical:
Erythematous, scaling papules
and plaques, sometimes with a
greasy
g
y yyellow appearance.
pp
“Seborrheic areas”
– Scalp, ears, eyebrows,
eyelid margins
margins, nasolabial
area.
Changes those of an acute,
subacute or chronic spongiotic
subacute,
dermatitis.
Chronic spongiotic
dermatitis looks
psoriasiform!
Seborrheic dermatitis
Histology:
gy
– Spongiosis
– Psoriasiform
hyperplasia – less so
than psoriasis, usually.
– Folliculocentric
parakeratosis and
scale crusts
– PVLI
3 features help differentiate…
Case 9
Mycosis fungoides
Most common
primary cutaneous
lymphoma.
T cells:
– CD2+, CD3+, CD4+,
CD8- and CD7-
Patch – plaque –
tumor
Histology: (plaque stage)
– Compact hyperkeratosis,
parakeratosis, psoriasiform
hyperplasia.
– Variably dense infiltrate of
mononuclear cells in the papillary
dermis.
– Epidermotropism
– Pautrier’s microabcesses
– Lymphocytes with a clear
perinuclear halo, aligned along
the basal layer – “beading”
beading
– Lymphocytes with
hyperconvoluted nuclei –
“cerebriform”
– Epidermal lymphocytes larger
than dermal lymphocytes
Psoriasis versus:
– LSC/Prurigo
– Seborrheic dermatitis
– SCCIS
– CTCL
– Hypertrophic LP – when on shins…psoriasis w/ scalp,
intergluteal fold involvement
– With erythroderma:
y
Sezary
y Sx,, PRP,, drug.
g
– With guttate form: small plaque parapsoriasis, PLC, secondary
syphilis, PR, tinea
– With pustules: AGEP (drug), tinea, SneddonSneddon-Wilkinson