Proceedings of the Fifth SKIN SPECTRUM SUMMIT

SSS-2019 02-10-20_Layout 1 2/12/2020 5:18 PM Page 26
PSORIASIS
How to spot psoriasis in
Fitzpatrick skin types V and VI
Dr. Andrew F. Alexis
As part of his talk on psoriasis
in skin of colour at Skin
Spectrum Summit in
Toronto, Dr. Andrew F. Alexis detailed
a number of ways that the
skin condition can present differently
in darker skin.
This was part of a larger talk debunking
myths surrounding the prevalence
of psoriasis in darker skin and
comparing the disease’s colour presentation
and shape across skin
shades.
He began his talk by discussing
how psoriasis in darker skin has come
to be understood better over the
years. Although it was once considered
a “rare” skin condition in people
of colour, Dr. Alexis debunked that
myth.
“This was due to underreporting,”
he said. “Thankfully, more recent studies
have shown that the prevalence of
psoriasis in darker skin is far from
rare; in fact, these studies have shown
the prevalence rate [to be] in the one
to two per cent range.”
As far as psoriasis in darker skin
types goes, Dr. Alexis said that sometimes
the presentation is classic; it is
usually sharply demarcated, brick red
or pink, and can have plaques with silvery
scales.
“However, once we get into the
more darkly pigmented ranges of the
spectrum, including Fitzpatrick type V
and type VI, the redness may be
masked by melanin and may start to
look a little more purple or violaceous
than red,” he said.
The sharp lines of demarcation
and characteristic scale will still be
present, he said, but because of the
purplish hue, it can be difficult to distinguish
from lichen planus, another
papulosquamous disorder.
One factor that can help differentiate
the two disorders is the location
on the body where it is found.
“Lichen planus tends to favour the
flexural side of extremities, including
the wrist and forearm, while psoriasis
will be more extensor,” he said.
The shapes of the lesions of the
two disorders differ as well, he said.
“In lichen planus, plaques tend to
be more flat topped and polygonal.”
Hyperpigmented lesions ranging
from dark brown to red brown may
appear on darker skin as opposed to
red lesions on lighter skin.
Certain skincare practices may
also hide the character of the scale. In
his presentation, Dr. Alexis gave the
example of a patient who had a nightly
routine of applying petrolatum ointment
on his scaly plaques and scraping
off the scales with a kitchen knife.
“This is a lesson to be learned as
far as asking about what patients are
doing and considering how that might
impact the clinical appearance of the
plaques in front of us,” he said.
Common areas,
modalities of
treatment and
subtypes of Pso
Dr. Gary Sibbald
In his presentation at Skin Spectrum
Summit in Toronto, Dr.
Gary Sibbald spoke about topical
treatments for psoriasis. He
discussed the “many faces of psoriasis,”
including the subtypes; the
different modalities of treatment;
and the common areas at which
psoriasis tends to manifest itself.
Psoriasis subtypes include plaque
psoriasis, guttate psoriasis, pustular
psoriasis and erythrodermic psoriasis,
said Dr. Sibbald. He went on to point
out that there is “‘A’ evidence for most
of what we do in psoriasis,” referring
to randomized controlled trials.
He said that for any patient with
5% or less psoriasis coverage, he
would recommend starting with
26 • Proceedings of 2019 SKIN SPECTRUM SUMMIT