psoriasis

1. PSORIASISPSORIASIS

2.  PsoriasisPsoriasis is a disease whichis a disease which
affects theaffects the skinskin andand jointsjoints..
 It commonly causes red scalyIt commonly causes red scaly
patches to appear on the skin.patches to appear on the skin.
 The scaly patches caused byThe scaly patches caused by
psoriasis, called psoriaticpsoriasis, called psoriatic
plaques, are areas ofplaques, are areas of
inflammation and excessiveinflammation and excessive
skin production.skin production.
 Skin rapidly accumulates atSkin rapidly accumulates at
these sites and takes a silvery-these sites and takes a silvery-
white appearance.white appearance.
 Plaques frequently occur on thePlaques frequently occur on the
skin of the elbows and knees,skin of the elbows and knees,
but can affect any areabut can affect any area
including the scalp and genitals.including the scalp and genitals.

3.  Psoriasis is an inflammatory skin disease in which skin cellsPsoriasis is an inflammatory skin disease in which skin cells
replicate at an extremely rapid rate. New skin cells are producedreplicate at an extremely rapid rate. New skin cells are produced
about eight times faster than normal--over several days instead ofabout eight times faster than normal--over several days instead of
a month--but the rate at which old cells slough off is unchanged.a month--but the rate at which old cells slough off is unchanged.
This causes cells to build up on the skin's surface, forming thickThis causes cells to build up on the skin's surface, forming thick
patches, or plaques, of red sores (lesions) covered with flaky,patches, or plaques, of red sores (lesions) covered with flaky,
silvery-white dead skin cells (scales).silvery-white dead skin cells (scales).

4.  The disorder is a chronic recurring conditionThe disorder is a chronic recurring condition
which varies in severity from minor localisedwhich varies in severity from minor localised
patches to complete body coverage.patches to complete body coverage.
 Fingernails and toenails are frequently affectedFingernails and toenails are frequently affected
(psoriatic nail dystrophy) - and can be seen as an(psoriatic nail dystrophy) - and can be seen as an
isolated finding.isolated finding.
 Psoriasis can also cause inflammation of thePsoriasis can also cause inflammation of the
joints, which is known asjoints, which is known as psoriatic arthritispsoriatic arthritis..

5.  The cause of psoriasis is not known, but it is believedThe cause of psoriasis is not known, but it is believed
to have a genetic component.to have a genetic component.
 Several factors are thought to aggravate psoriasis.Several factors are thought to aggravate psoriasis.
These includeThese include stressstress,, excessive alcohol consumptionexcessive alcohol consumption,,
andand smokingsmoking..
 Individuals with psoriasis may suffer from depressionIndividuals with psoriasis may suffer from depression
and loss of self-esteem.and loss of self-esteem.
 As such, quality of life is an important factor inAs such, quality of life is an important factor in
evaluating the severity of the disease.evaluating the severity of the disease.
 Certain medicines, includingCertain medicines, including lithium saltlithium salt andand
beta blockersbeta blockers, have been reported to trigger or, have been reported to trigger or
aggravate the disease.aggravate the disease.

6.  There are two main hypotheses about the process that occurs inThere are two main hypotheses about the process that occurs in
the development of the disease.the development of the disease.
 The first considers psoriasis as primarily a disorder of excessiveThe first considers psoriasis as primarily a disorder of excessive
growth and reproduction of skin cells. The problem is simplygrowth and reproduction of skin cells. The problem is simply
seen as a fault of theseen as a fault of the epidermisepidermis and itsand its keratinocyteskeratinocytes..
 The second hypothesis sees the disease as being anThe second hypothesis sees the disease as being an
immune-mediated disorderimmune-mediated disorder in which the excessive reproductionin which the excessive reproduction
of skin cells is secondary to factors produced by the immuneof skin cells is secondary to factors produced by the immune
system.system. T cellsT cells (which normally help protect the body against(which normally help protect the body against
infection) become active, migrate to the dermis and trigger theinfection) become active, migrate to the dermis and trigger the
release ofrelease of cytokinescytokines (tumor necrosis factor-alpha TNFα, in(tumor necrosis factor-alpha TNFα, in
particular) which cause inflammation and the rapid productionparticular) which cause inflammation and the rapid production
of skin cells. It is not known what initiates the activation of the Tof skin cells. It is not known what initiates the activation of the T
cells.cells.
 The immune-mediated model of psoriasis has been supported byThe immune-mediated model of psoriasis has been supported by
the observation that immunosuppressant medications can clearthe observation that immunosuppressant medications can clear
psoriasis plaques.psoriasis plaques.

7.  Plaque psoriasisPlaque psoriasis (psoriasis vulgaris)(psoriasis vulgaris) is theis the
most common form of psoriasis. It affects 80 tomost common form of psoriasis. It affects 80 to
90% of people with psoriasis. Plaque psoriasis90% of people with psoriasis. Plaque psoriasis
typically appears as raised areas of inflamed skintypically appears as raised areas of inflamed skin
covered with silvery white scaly skin. These areascovered with silvery white scaly skin. These areas
are called plaques.are called plaques.
Types of PsoriasisTypes of Psoriasis

8.  Flexural psoriasisFlexural psoriasis (inverse(inverse
psoriasis)psoriasis) appears as smoothappears as smooth
inflamed patches of skin. It occursinflamed patches of skin. It occurs
in skin folds, particularly aroundin skin folds, particularly around
the genitals (between the thigh andthe genitals (between the thigh and
groin), the armpits, under angroin), the armpits, under an
overweight stomach (pannus), andoverweight stomach (pannus), and
under the breasts (inframammaryunder the breasts (inframammary
fold). It is aggravated by frictionfold). It is aggravated by friction
and sweat, and is vulnerable toand sweat, and is vulnerable to
fungal infections.fungal infections.
 Guttate psoriasisGuttate psoriasis is characterizedis characterized
by numerous small oval (teardrop-by numerous small oval (teardrop-
shaped) spots. These numerousshaped) spots. These numerous
spots of psoriasis appear over largespots of psoriasis appear over large
areas of the body, such as theareas of the body, such as the
trunk, limbs, and scalp. Guttatetrunk, limbs, and scalp. Guttate
psoriasis is associated withpsoriasis is associated with
streptococcal throat infectionstreptococcal throat infection

9.  Pustular psoriasisPustular psoriasis appears as raised bumps thatappears as raised bumps that
are filled with non-infectious pus (pustules). Theare filled with non-infectious pus (pustules). The
skin under and surrounding pustules is red andskin under and surrounding pustules is red and
tender. Pustular psoriasis can be localised,tender. Pustular psoriasis can be localised,
commonly to the hands and feet , or generalisedcommonly to the hands and feet , or generalised
with widespread patches occurring randomly onwith widespread patches occurring randomly on
any part of the body.any part of the body.

10.  Nail psoriasisNail psoriasis produces a variety of changes inproduces a variety of changes in
the appearance of finger and toe nails. Thesethe appearance of finger and toe nails. These
changes include discolouring under the nailchanges include discolouring under the nail
plate, pitting of the nails, lines going across theplate, pitting of the nails, lines going across the
nails, thickening of the skin under the nail, andnails, thickening of the skin under the nail, and
the loosening (the loosening (onycholysisonycholysis) and crumbling of the) and crumbling of the
nail.nail.

13.  Psoriatic arthritisPsoriatic arthritis involvesinvolves
joint and connective tissuejoint and connective tissue
inflammation.inflammation.
 Psoriatic arthritis can affectPsoriatic arthritis can affect
any joint but is mostany joint but is most
common in the joints of thecommon in the joints of the
fingers and toes. This canfingers and toes. This can
result in a sausage-shapedresult in a sausage-shaped
swelling of the fingers andswelling of the fingers and
toes known as dactylitis.toes known as dactylitis.
Psoriatic arthritis can alsoPsoriatic arthritis can also
affect the hips, knees andaffect the hips, knees and
spine (spondylitis). About 10-spine (spondylitis). About 10-
15% of people who have15% of people who have
psoriasis also have psoriaticpsoriasis also have psoriatic
arthritis.arthritis.

14.  Erythrodermic psoriasisErythrodermic psoriasis
involves the widespreadinvolves the widespread
inflammation and exfoliationinflammation and exfoliation
of the skin over most of theof the skin over most of the
body surface. It may bebody surface. It may be
accompanied by severeaccompanied by severe
itching, swelling and pain.itching, swelling and pain.
 It is often the result of anIt is often the result of an
exacerbation of unstableexacerbation of unstable
plaque psoriasis, particularlyplaque psoriasis, particularly
following the abruptfollowing the abrupt
withdrawal of systemicwithdrawal of systemic
treatment. This form oftreatment. This form of
psoriasis can be fatal, as thepsoriasis can be fatal, as the
extreme inflammation andextreme inflammation and
exfoliation disrupt the body'sexfoliation disrupt the body's
ability to regulate temperatureability to regulate temperature
and for the skin to performand for the skin to perform
barrier functions.barrier functions.

16.  A diagnosis of psoriasis is usually based on theA diagnosis of psoriasis is usually based on the
appearance of the skin. There are no specialappearance of the skin. There are no special
blood tests or diagnostic procedures forblood tests or diagnostic procedures for
psoriasis. Sometimes a skin biopsy, or scraping,psoriasis. Sometimes a skin biopsy, or scraping,
may be needed to rule out other disorders and tomay be needed to rule out other disorders and to
confirm the diagnosis. Skin from a biopsy willconfirm the diagnosis. Skin from a biopsy will
show clubbed pegs if positive for psoriasis.show clubbed pegs if positive for psoriasis.
 Another sign of psoriasis is that when theAnother sign of psoriasis is that when the
plaques are scraped, one can see pinpointplaques are scraped, one can see pinpoint
bleeding from the skin below (Auspitz's sign).bleeding from the skin below (Auspitz's sign).

17. Treatment optionsTreatment options
 There can be substantial variation between individualsThere can be substantial variation between individuals
in the effectiveness of specific psoriasis treatments.in the effectiveness of specific psoriasis treatments.
Because of this, dermatologists often use a trial-and-Because of this, dermatologists often use a trial-and-
error approach to finding the most appropriateerror approach to finding the most appropriate
treatment for their patient.treatment for their patient.
 The decision to employ a particular treatment is basedThe decision to employ a particular treatment is based
on the type of psoriasis, its location, extent and severity.on the type of psoriasis, its location, extent and severity.
The patient’s age, gender, quality of life, comorbidities,The patient’s age, gender, quality of life, comorbidities,
and attitude toward risks associated with the treatmentand attitude toward risks associated with the treatment
are also taken into consideration.are also taken into consideration.

18.  Medications with the least potential for adverseMedications with the least potential for adverse
reactions are preferentially employed.reactions are preferentially employed.
 As a first step, medicated ointments or creams areAs a first step, medicated ointments or creams are
applied to the skin. If topical treatment fails to achieveapplied to the skin. If topical treatment fails to achieve
the desired goal then the next step would be to exposethe desired goal then the next step would be to expose
the skin to ultraviolet (UV) radiation. This type ofthe skin to ultraviolet (UV) radiation. This type of
treatment is called phototherapy.treatment is called phototherapy.
 The third step involves the use of medications whichThe third step involves the use of medications which
are taken internally by pill or injection : systemicare taken internally by pill or injection : systemic
treatment.treatment.
 Over time, psoriasis can become resistant to a specificOver time, psoriasis can become resistant to a specific
therapy. Treatments may be periodically changed totherapy. Treatments may be periodically changed to
prevent resistance developing (tachyphylaxis) and toprevent resistance developing (tachyphylaxis) and to
reduce the chance of adverse reactions occurring:reduce the chance of adverse reactions occurring:
treatment rotation.treatment rotation.

20. Topical treatmentTopical treatment
 Salicylic acidSalicylic acid
- Keratolytic agents, weak antifungals,Keratolytic agents, weak antifungals,
antibacterial agentsantibacterial agents
- Remove accumulated scale, allow topical agentsRemove accumulated scale, allow topical agents
to pass throughto pass through
- AE: irritation, salicylism (N&V, tinnitus)AE: irritation, salicylism (N&V, tinnitus)

21.  Coal TarCoal Tar
- Prefered for limited or scalp psoriasisPrefered for limited or scalp psoriasis
- Can be effective in widespread psoriasisCan be effective in widespread psoriasis
- Antimitotic, anti-pruriticAntimitotic, anti-pruritic
- No quick onset but longer remissionNo quick onset but longer remission
- Often combined with SA, UV light therapyOften combined with SA, UV light therapy
- 2 types: Crude coal tar and Liquor picis carbonis2 types: Crude coal tar and Liquor picis carbonis

22. DithranolDithranol
 May restore normal epidermal proliferation andMay restore normal epidermal proliferation and
keratinizationkeratinization
 Useful in thick plaque psoriasisUseful in thick plaque psoriasis
 Commonly used with SACommonly used with SA
 2 treatment approach: long contact and short2 treatment approach: long contact and short
contactcontact
 Stains clothes, irritating to normal skinStains clothes, irritating to normal skin

23. Topical CSTopical CS
 Anti-inflammatory, immunosuppressiveAnti-inflammatory, immunosuppressive
 Quick onset than coal tar and dithranolQuick onset than coal tar and dithranol
 Tachyphylaxis can occurTachyphylaxis can occur
 High potent agents used in severe cases, thickHigh potent agents used in severe cases, thick
plaquesplaques
 AE local and systemicAE local and systemic
 Should not be stopped abruptly – reboundShould not be stopped abruptly – rebound
psoriasispsoriasis

24. PhototherapyPhototherapy
 UVA, UVB, PUVAUVA, UVB, PUVA
 UVB preferedUVB prefered
 Administered by lamp, sunlight exposure aloneAdministered by lamp, sunlight exposure alone
or in combo with another topical agentor in combo with another topical agent
 PUVA (methoxsalen) given PO 2 hours beforePUVA (methoxsalen) given PO 2 hours before
UVA or lotion applied 30mins before exposureUVA or lotion applied 30mins before exposure
 AE: itch, edemaAE: itch, edema

25. Systemic TherapySystemic Therapy
 ImmunomodulatorsImmunomodulators
- Cyclosporin, methotrexate commonly usedCyclosporin, methotrexate commonly used
- Antibiotics in case of secondary bacterialAntibiotics in case of secondary bacterial
infectionsinfections

26.  Systemic agents are generally recommended forSystemic agents are generally recommended for
patients with moderate-to-severe disease.patients with moderate-to-severe disease.
 Moderate disease is defined as greater than 5%Moderate disease is defined as greater than 5%
body-surface area involvement; severe disease isbody-surface area involvement; severe disease is
defined by greater than 10%defined by greater than 10%

27.  Psoriasis is a lifelong condition.Psoriasis is a lifelong condition.
 There is currently no cure but various treatments canThere is currently no cure but various treatments can
help to control the symptoms. Many of the mosthelp to control the symptoms. Many of the most
effective agents used to treat severe psoriasis carry aneffective agents used to treat severe psoriasis carry an
increased risk of significant morbidity including skinincreased risk of significant morbidity including skin
cancers, lymphoma and liver disease.cancers, lymphoma and liver disease.
 Psoriasis does get worse over time but it is not possiblePsoriasis does get worse over time but it is not possible
to predict who will go on to develop extensiveto predict who will go on to develop extensive
psoriasis or those in whom the disease may appear topsoriasis or those in whom the disease may appear to
vanish.vanish.
 Individuals will often experience flares and remissionsIndividuals will often experience flares and remissions
throughout their lives. Controlling the signs andthroughout their lives. Controlling the signs and
symptoms typically requires lifelong therapy.symptoms typically requires lifelong therapy.
SummarySummary