PSORIASISPSORIASIS

PsoriasisPsoriasis is a disease is a disease which affects the which affects the skin and and joints. .

It commonly causes red It commonly causes red scaly patches to appear on scaly patches to appear on the skin. the skin.

The scaly patches caused The scaly patches caused by psoriasis, called by psoriasis, called psoriatic plaques, are areas psoriatic plaques, are areas of inflammation and of inflammation and excessive skin production. excessive skin production.

Skin rapidly accumulates at Skin rapidly accumulates at these sites and takes a these sites and takes a silvery-white appearance.silvery-white appearance.

Plaques frequently occur on Plaques frequently occur on the skin of the elbows and the skin of the elbows and knees, but can affect any knees, but can affect any area including the scalp area including the scalp and genitals. and genitals.

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

The disorder is a chronic recurring The disorder is a chronic recurring conditioncondition

which varies in severity from minor which varies in severity from minor localised patches to complete body localised patches to complete body coverage. coverage.

Fingernails and toenails are frequently Fingernails and toenails are frequently affected (psoriatic nail dystrophy) - affected (psoriatic nail dystrophy) - and can be seen as an isolated finding. and can be seen as an isolated finding.

Psoriasis can also cause inflammation Psoriasis can also cause inflammation of the joints, which is known as of the joints, which is known as psoriatic arthritis. .

The cause of psoriasis is not known, but it is The cause of psoriasis is not known, but it is believed to have a genetic component.believed to have a genetic component.

Several factors are thought to aggravate Several factors are thought to aggravate psoriasis. These include psoriasis. These include stress, , excessive alcohol consumption, and , and smoking..

Individuals with psoriasis may suffer from Individuals with psoriasis may suffer from depression and loss of self-esteem. depression and loss of self-esteem.

As such, quality of life is an important factor As such, quality of life is an important factor in evaluating the severity of the disease. in evaluating the severity of the disease.

Certain medicines, including Certain medicines, including lithium salt and and beta blockers, have been reported to trigger , have been reported to trigger or aggravate the disease. or aggravate the disease.

There are two main hypotheses about the process that There are two main hypotheses about the process that occurs in the development of the disease. occurs in the development of the disease.

The first considers psoriasis as primarily a disorder of The first considers psoriasis as primarily a disorder of excessive growth and reproduction of skin cells. The excessive growth and reproduction of skin cells. The problem is simply seen as a fault of the problem is simply seen as a fault of the epidermis and its and its keratinocytes..

The second hypothesis sees the disease as being an The second hypothesis sees the disease as being an immune-mediated disorder in which the excessive in which the excessive reproduction of skin cells is secondary to factors reproduction of skin cells is secondary to factors produced by the immune system. produced by the immune system. T cells (which normally (which normally help protect the body against infection) become active, help protect the body against infection) become active, migrate to the dermis and trigger the release of migrate to the dermis and trigger the release of cytokines (tumor necrosis factor-alpha TNFα, in (tumor necrosis factor-alpha TNFα, in particular) which cause inflammation and the rapid particular) which cause inflammation and the rapid production of skin cells. It is not known what initiates production of skin cells. It is not known what initiates the activation of the T cells.the activation of the T cells.

The immune-mediated model of psoriasis has been The immune-mediated model of psoriasis has been supported by the observation that immunosuppressant supported by the observation that immunosuppressant medications can clear psoriasis plaques. medications can clear psoriasis plaques.

Plaque psoriasisPlaque psoriasis (psoriasis (psoriasis vulgaris) vulgaris) is the most common form is the most common form of psoriasis. It affects 80 to 90% of of psoriasis. It affects 80 to 90% of people with psoriasis. Plaque people with psoriasis. Plaque psoriasis typically appears as raised psoriasis typically appears as raised areas of inflamed skin covered with areas of inflamed skin covered with silvery white scaly skin. These areas silvery white scaly skin. These areas are called plaques.are called plaques.

Types of PsoriasisTypes of Psoriasis

Flexural psoriasisFlexural psoriasis (inverse (inverse psoriasis)psoriasis) appears as smooth appears as smooth inflamed patches of skin. It inflamed patches of skin. It occurs in skin folds, occurs in skin folds, particularly around the particularly around the genitals (between the thigh genitals (between the thigh and groin), the armpits, under and groin), the armpits, under an overweight stomach an overweight stomach (pannus), and under the (pannus), and under the breasts (inframammary fold). breasts (inframammary fold). It is aggravated by friction and It is aggravated by friction and sweat, and is vulnerable to sweat, and is vulnerable to fungal infections.fungal infections.

Guttate psoriasisGuttate psoriasis is is characterized by numerous characterized by numerous small oval (teardrop-shaped) small oval (teardrop-shaped) spots. These numerous spots of spots. These numerous spots of psoriasis appear over large psoriasis appear over large areas of the body, such as the areas of the body, such as the trunk, limbs, and scalp. trunk, limbs, and scalp. Guttate psoriasis is associated Guttate psoriasis is associated with streptococcal throat with streptococcal throat infectioninfection

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

Nail psoriasisNail psoriasis produces a variety of produces a variety of changes in the appearance of finger changes in the appearance of finger and toe nails. These changes include and toe nails. These changes include discolouring under the nail plate, discolouring under the nail plate, pitting of the nails, lines going pitting of the nails, lines going across the nails, thickening of the across the nails, thickening of the skin under the nail, and the skin under the nail, and the loosening (loosening (onycholysis) and ) and crumbling of the nail.crumbling of the nail.

Psoriatic arthritis Psoriatic arthritis involves joint and involves joint and connective tissue connective tissue inflammation. inflammation.

Psoriatic arthritis can Psoriatic arthritis can affect any joint but is affect any joint but is most common in the most common in the joints of the fingers and joints of the fingers and toes. This can result in a toes. This can result in a sausage-shaped swelling sausage-shaped swelling of the fingers and toes of the fingers and toes known as dactylitis. known as dactylitis. Psoriatic arthritis can Psoriatic arthritis can also affect the hips, also affect the hips, knees and spine knees and spine (spondylitis). About 10-(spondylitis). About 10-15% of people who have 15% of people who have psoriasis also have psoriasis also have psoriatic arthritis.psoriatic arthritis.

Erythrodermic Erythrodermic psoriasispsoriasis involves the involves the widespread inflammation widespread inflammation and exfoliation of the skin and exfoliation of the skin over most of the body over most of the body surface. It may be surface. It may be accompanied by severe accompanied by severe itching, swelling and itching, swelling and pain. pain.

It is often the result of an It is often the result of an exacerbation of unstable exacerbation of unstable plaque psoriasis, plaque psoriasis, particularly following the particularly following the abrupt withdrawal of abrupt withdrawal of systemic treatment. This systemic treatment. This form of psoriasis can be form of psoriasis can be fatal, as the extreme fatal, as the extreme inflammation and inflammation and exfoliation disrupt the exfoliation disrupt the body's ability to regulate body's ability to regulate temperature and for the temperature and for the skin to perform barrier skin to perform barrier functions.functions.

A diagnosis of psoriasis is usually based A diagnosis of psoriasis is usually based on the appearance of the skin. There are on the appearance of the skin. There are no special blood tests or diagnostic no special blood tests or diagnostic procedures for psoriasis. Sometimes a procedures for psoriasis. Sometimes a skin biopsy, or scraping, may be needed skin biopsy, or scraping, may be needed to rule out other disorders and to confirm to rule out other disorders and to confirm the diagnosis. Skin from a biopsy will the diagnosis. Skin from a biopsy will show clubbed pegs if positive for show clubbed pegs if positive for psoriasis. psoriasis.

Another sign of psoriasis is that when the Another sign of psoriasis is that when the plaques are scraped, one can see plaques are scraped, one can see pinpoint bleeding from the skin below pinpoint bleeding from the skin below (Auspitz's sign).(Auspitz's sign).

Treatment optionsTreatment options There can be substantial variation between There can be substantial variation between

individuals in the effectiveness of specific individuals in the effectiveness of specific psoriasis treatments. Because of this, psoriasis treatments. Because of this, dermatologists often use a trial-and-error dermatologists often use a trial-and-error approach to finding the most appropriate approach to finding the most appropriate treatment for their patient. treatment for their patient.

The decision to employ a particular treatment is The decision to employ a particular treatment is based on the type of psoriasis, its location, based on the type of psoriasis, its location, extent and severity. The patient’s age, gender, extent and severity. The patient’s age, gender, quality of life, comorbidities, and attitude quality of life, comorbidities, and attitude toward risks associated with the treatment are toward risks associated with the treatment are also taken into consideration.also taken into consideration.

Medications with the least potential for Medications with the least potential for adverse reactions are preferentially employed. adverse reactions are preferentially employed.

As a first step, medicated ointments or creams As a first step, medicated ointments or creams are applied to the skin. If topical treatment are applied to the skin. If topical treatment fails to achieve the desired goal then the next fails to achieve the desired goal then the next step would be to expose the skin to ultraviolet step would be to expose the skin to ultraviolet (UV) radiation. This type of treatment is called (UV) radiation. This type of treatment is called phototherapy. phototherapy.

The third step involves the use of medications The third step involves the use of medications which are taken internally by pill or injection : which are taken internally by pill or injection : systemic treatment.systemic treatment.

Over time, psoriasis can become resistant to a Over time, psoriasis can become resistant to a specific therapy. Treatments may be specific therapy. Treatments may be periodically changed to prevent resistance periodically changed to prevent resistance developing (tachyphylaxis) and to reduce the developing (tachyphylaxis) and to reduce the chance of adverse reactions occurring: chance of adverse reactions occurring: treatment rotation.treatment rotation.

Topical treatmentTopical treatment

Salicylic acidSalicylic acid- Keratolytic agents, weak antifungals, Keratolytic agents, weak antifungals,

antibacterial agentsantibacterial agents- Remove accumulated scale, allow Remove accumulated scale, allow

topical agents to pass throughtopical agents to pass through- AE: irritation, salicylism (N&V, AE: irritation, salicylism (N&V,

tinnitus)tinnitus)

Coal TarCoal Tar- Prefered for limited or scalp psoriasisPrefered for limited or scalp psoriasis- Can be effective in widespread Can be effective in widespread

psoriasispsoriasis- Antimitotic, anti-pruriticAntimitotic, anti-pruritic- No quick onset but longer remissionNo quick onset but longer remission- Often combined with SA, UV light Often combined with SA, UV light

therapytherapy- 2 types: Crude coal tar and Liquor 2 types: Crude coal tar and Liquor

picis carbonispicis carbonis

DithranolDithranol

May restore normal epidermal May restore normal epidermal proliferation and keratinizationproliferation and keratinization

Useful in thick plaque psoriasisUseful in thick plaque psoriasis Commonly used with SACommonly used with SA 2 treatment approach: long contact 2 treatment approach: long contact

and short contactand short contact Stains clothes, irritating to normal Stains clothes, irritating to normal

skinskin

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 High potent agents used in severe

cases, thick plaquescases, thick plaques AE local and systemicAE local and systemic Should not be stopped abruptly – Should not be stopped abruptly –

rebound psoriasisrebound psoriasis

PhototherapyPhototherapy

UVA, UVB, PUVAUVA, UVB, PUVA UVB preferedUVB prefered Administered by lamp, sunlight Administered by lamp, sunlight

exposure alone or in combo with exposure alone or in combo with another topical agentanother topical agent

PUVA (methoxsalen) given PO 2 hours PUVA (methoxsalen) given PO 2 hours before UVA or lotion applied 30mins before UVA or lotion applied 30mins before exposurebefore exposure

AE: itch, edemaAE: itch, edema

Systemic TherapySystemic Therapy

ImmunomodulatorsImmunomodulators- Cyclosporin, methotrexate Cyclosporin, methotrexate

commonly usedcommonly used

- Antibiotics in case of secondary Antibiotics in case of secondary bacterial infectionsbacterial infections

Systemic agents are generally Systemic agents are generally recommended for patients with recommended for patients with moderate-to-severe disease. moderate-to-severe disease.

Moderate disease is defined as Moderate disease is defined as greater than 5% body-surface area greater than 5% body-surface area involvement; severe disease is involvement; severe disease is defined by greater than 10%defined by greater than 10%

Psoriasis is a lifelong condition.Psoriasis is a lifelong condition. There is currently no cure but various There is currently no cure but various

treatments can help to control the symptoms. treatments can help to control the symptoms. Many of the most effective agents used to Many of the most effective agents used to treat severe psoriasis carry an increased risk treat severe psoriasis carry an increased risk of significant morbidity including skin of significant morbidity including skin cancers, lymphoma and liver disease. cancers, lymphoma and liver disease.

Psoriasis does get worse over time but it is Psoriasis does get worse over time but it is not possible to predict who will go on to not possible to predict who will go on to develop extensive psoriasis or those in whom develop extensive psoriasis or those in whom the disease may appear to vanish. the disease may appear to vanish.

Individuals will often experience flares and Individuals will often experience flares and remissions throughout their lives. Controlling remissions throughout their lives. Controlling the signs and symptoms typically requires the signs and symptoms typically requires lifelong therapy.lifelong therapy.

SummarySummary