4. Definition:
Psoriasis is a chronic recurrent, papulo squamous
disorder of the skin.
Psoriasis is not contagious. The exact cause of
psoriasis is not known, but the body's natural
defense system
The patches (called plaques) are made up of dead
skin cells that form thick layers.
The body replaces normal skin cells every 28 days,
but in psoriasis, skin cells are replaced every 3 to 6
days
6. History Of Psoriasis:
The word psoriasis is derived from Greek word PSORA means
ITCHING
The Greek physician Galen (133-200 A.D.) identified
psoriasis as a skin disease through clinical observation and
was the first to call it psoriasis
He use the term psoriasis vulgaris to refer all dermal complaints.
7. In the 1960, investigation of psoriasis as an
autoimmune condition began. Psoriatic arthritis was
finally identified as a clinical entity in its own right.
1970,Twentieth-century recognition of the
underlying mechanisms of psoriasis and treatments
based on evidence of effectiveness for each person.
These include topical (applied to the skin), laser and
phototherapy, and systemic (oral, injected or IV
medications that suppress the immune system).
8. 1998:
Biologic medications, introduced in the latter part
of the 20th century, became the cutting edge for
psoriasis research and treatments. These agents are
made from substances found in living cells and act
on the body's immune system. They treat psoriasis
by targeting overzealous immune cells, which cause
the disease
10. Incidence:
It affect 2% of indian population
230/100,000 person-years
In both sex it is noted
The disease can start at any age but the peak onset in
the second or third decades.
35% have a family history of psoriasis
12. Genetics:
It is a multifactorial genetic disease that requires
both polygenic and environmental factors
About 35% has a strong familyhistory
It has a strong correlation with HLA antigens.
13. IMMUNOPATHOGENESIS:
It has a T cells mediated immunopathogenesis
There is an interaction between environmental,
genetic and immunological factors.
Antigens may be environmental antigens,super
antigens or auto antigens
These antigens are taken by the antigen presenting
cells[APC] in the skin.
14. APC migrates from skin to lymphnodes,where they
encounter Tcells.
These Tcells became activated through a series of
interaction with APC.
Once it get activated it again migrate back to skin
and secrete pro inflammatory cytokines –
[IL2,interferon]
15. This induce the further production of cytokines
including tumor necrosis factor
This induce cytokines induce epidermal and vascular
changes that leads to psoriasis plaques.
TNF is involved in many important cellular function
such as proliferation,activation,migration and
apoptosis.
17. Pathophysiological events:
Epidermal proliferation:
There is an increase in the number of
proliferating keratinocytes in the basal layer of the
epidermal and there is loss of differentiation.
This causes the thick silvery scale.
The growth rate of psoriatic eruption is
upto 10 times that of normal epidermis
18. Expansion of the dermal vasculature:
The blood vessel in the upper dermis become dilated
and hyper permiable and increased in number
Accumulation of inflammatory cells like netrophills
and T lymphocytes in dermis and epidermis
19. Precipitating factors:
Physical trauma to the skin can precipitate psoriasis
in the damaged skin. This know as Koebner
phenomenon. Rubbing and scratching stimulate the
proliferative process.
Infection :Streptococcal infection precipitate Guttate
psoriasis.
Drugs: Beta blockers,lithum,antimalarials and
withdrawal of systemic steriods aggravate psoriasis.
20. Exposure to sunlight can aggravate psoriasis in about
10% of patients, although in the majority,it has a
beneficial effects.
Psychological stress can exacerbate psoriasis.
22. Psoriasis vulgaris:
Psoriasis vulgaris [ vulgaris – common]is the
commonest type.
It is characterized by well defined erythematous
papules and plaques with silvery white scales.
On removal of loosely attached scales,minute
bleeding points are seen [“auspitz sign”].
Papules and plaques coalesce to form polycylic or
serpiginous patterns.
23.
24. Sites:
Elbow
Knees
Scalp hair margin
Sacrum
Lesions are bilateral and often symmertical.
27. Guttate psoriasis:
This form is less common; only about 10% of
patients have this type.
Guttate psoriasis often appears after someone suffers
from streptococcal sore throat.
It commonly starts in childhood or adolescence with
the sudden appearance of drop-sized patches
(guttate means Drop-like).
These lesions may spread to cover large areas of the
upper body, legs, arms, and scalp.
28. Acute symmetrical eruption of a shower of small
papular lesions usually on the trunk.
The prognosis is good with spontaneous resolution
but may evolve intochronic plaque psoriasis.
Differential diagonsis:
Pityrisis rosea – which has a classical
morophololgy of oval papules with peripheral scaling
and central wrinkling.
30. Flexural psoriasis:
It affect the flexor regions due to the moist and warm
environment in these regions,
It is commonly seen in elders
Sites:
axillae
groins
submammary areas
natal cleft
37. Palmo plantar psoriasis
Palms and soles are the area involved
There is hyperkeratosis and scaling which is not
easily removed
They may be painful fissures and bleeding
39. Scalp psoriasis:
Sharply margined pruritic plaques especially at the
occiput with thick adherent scales
It may be discrete or entire scalp
Scalp may be the only site only involved
Silvery scales, if present are typical of psoriasis.
42. It affect the matrix or nail bed in upto 50% of cases.
Timble pitting is the commonest change, folowed by
onycholysis
Discolouration of the nail bed resembling an oil drop
[oil ddrop sign].
Subungual hyperkeratosis affecs mainly the toe nails
44. Pustular psoriasis:
It is characterized by sterlite pustules, not papules,
arising on a normal skin
Two types:
localized pustular psoriasis
Chronic palmo plantar
Acrodermatitis continua
generalized pustular psoriasis
Acute GPP of von zumbusch
GPP of pregnancy
45. Chronic palmo plantar:
Palmoplantar pustulosis presents as crops of sterile
pustules occurring on one or both hands and/or feet.
They are associated with thickened, scaly, red skin
that easily develops painful cracks (fissures).
Palmoplantar pustulosis varies in severity and may
persist for many years. The discomfort can be
considerable, interfering with work and leisure
activities
46. Acrodermatitis continua:
Acrodermatitis continua of Hallopeau (ACH) is a
rare inflammatory disease characterised
by pustular eruptions beginning in the tips of fingers and
toes (digits). The pustules may vary in extent over
a chronic, recurrent course.
Acrodermatitis continua is often triggered
by localised trauma or infection at the distal phalanx (the
tip of the digit). 80% begin in only one digit, most
commonly the thumb.
The distal phalanx becomes red and scaly and develops
small pustules. The pustules often join together and on
bursting, reveal a painful, red and glazed area where new
pustules then develop.
47. Generalized pustular psoriasis
Acute GPP of von zumbusch:
von Zumbusch (acute) generalized
pustular psoriasis, (acute GPP) is the most
severe form of generalized pustular psoriasis, and
can be associated with life-threatening
complications.
48. c/f:
Initially the skin becomes dry, fiery red and tender.
Within hours, 2–3 mm pustules appear.
After a day, the small pustules to form lakes of pus
These dry out and peel to leave a glazed, smooth
surface on which new crops of pustules may appear.
Successive crops of pustules may appear and erupt
every few days or weeks.
49.
50. "pustular psoriasis of pregnancy"
Impetigo herpetiformis is a rare gestational
dermatosis with typical onset in the last trimester
of pregnancy and rapid resolution in the
postpartum period1,2 It is clinically and histologically
consistent with pustular psoriasis. This similarity
has led authors to name the disease "pustular
psoriasis of pregnancy"
51.
52. Psoriatic arthropathy:
It is a common sero negative polyarthritis
The most common symptoms are inflammatory
arthritis, and dry, scaly, thick, and inflamed skin.
However, the skin symptoms and the arthritis
symptoms frequently appear at different times, often
years apart, so their connection may not be obvious.
Psoriatic arthritis usually involves the joints of the
hands and feet, knees, and ankles, which can become
painful, swollen, hot, red, and stiff.
53. Pain and stiffness can also develop in the lower back,
buttocks, neck, and upper back.
Psoriasis skin symptoms may include pitting and
ridges in the fingernails and toenails. Nearly one
quarter of people with psoriasis have psoriatic
arthritis.
56. Prognosis:
Psoriasis is usually long-lasting, returns often (chronic), and
can be unpredictable.
Symptoms may come on suddenly (flare) and then improve
and go away (remission).
This cycle continues over and over.
In some cases, psoriasis may go away without treatment.
However, in moderate to severe cases, it is best to treat
psoriasis so that it does not get worse.
Psoriasis can cause significant stress and lowered self-esteem.
In one study, people with psoriasis reported a reduction in
functioning similar to that of people with cancer, arthritis,
heart disease, depression, and other serious conditions.
