Psoriasis is a chronic inflammatory skin condition characterized by red, scaly plaques. It affects 2-3% of the population and is caused by genetic and environmental factors that trigger an immune response. Common types include plaque, guttate, pustular, and erythrodermic psoriasis. Management involves topical therapies like corticosteroids and vitamin D analogues, phototherapy like UVB and PUVA, and systemic drugs for severe disease. Psoriasis is associated with increased risks of cardiovascular disease, metabolic syndrome, and arthritis.
2. Introduction
âPsoriasis is a complex, chronic, multifactorial, inflammatory disease that
involves hyperproliferation of the keratinocytes in the epidermis, with an
increase in the epidermal cell turnover rate
âEnvironmental, genetic, and immunologic factors appear to play a role
âCharacterized by red, scaly, sharply demarcated indurated papules and
plaques of various sizes
6. Type I and Type II Psoriasis
Type I psoriasis Type II psoriasis
<40 years age >40 years of age
About 75% About 25%
More severe Less severe than type I
HLA â Cw6 associated Less genetic association
Positive family history Family history usually absent
7. Aetiology
âEnvironmental, genetic, and immunologic factors appear to play a role
Systemic chronic
inflammation
⢠Psoriasis
Immune
factors
Environmental
factors
Heredity
PSORS1
HLA-Cw6
8. Pathogenesis
âTwo hypothesis
âKeratinocyte hyperproliferation may be due to immunological responses
â Cytokines released by lymphocytes and Langerhans cells may further stimulate the
inflammatory cells to cause an increased rate of epidermal cell turnover
âEpithelial cells themselves produce cytokines which promote proliferation of epithelial cells and
attract lymphocytes
9. Chapman A., El Miedany Y. (2017) Psoriasis. In: El Miedany Y. (eds) Comorbidity in Rheumatic Diseases. Springer, Cham.
10. Trigger Factors
âTrauma: Mechanical, chemical, radiation
âInfections: Streptococcus, staphylococcus, HIV
âStress
âAlcohol and smoking
âMetabolic factors: Hypocalcemia
âSunlight: Usually beneficial but in some may cause exacerbation
11. Trigger Factors: Drugs
Common Less common
âBeta blockers
âLithium
âAntimalarials
âNSAIDS
âACE Inhibitors
âAntibiotics
âInterferons
âTerbinafine
âBenzodiazepines
âDigoxin
âClonidine
âAmiodarone
âQuinidine
âGold
âTNF alpha inhibitors
âImiquimod
âFluoxetine
âCimetidine
12. History
âProminent itchy, red areas with increased skin scaling and peeling
âNew lesions appearing at sites of injury/trauma to the skin (Koebner
phenomenon)
âActual clearance of lesions following trauma to the skin (reverse Koebner
phenomenon)
âExacerbation in winter, improvement in summer
âSignificant joint pain, stiffness, deformity in 10-20%
âFamily history of similar skin condition
13.
14. Morphology
âLesions: Erythematous, scaly papules and plaques
âCharacteristic lesions include well-demarcated, erythematous plaques with adherent silvery
white scales
âCardinal features: Erythema, induration and scaling
âThe commonest type is psoriasis vulgaris
âSites: Mostly extensors sites are involved
âElbows, knees, scalp, lumbosacral areas, intergluteal clefts
âPalms/soles involved commonly
15. âAuspitz sign
âOn scraping a lesion of psoriasis with a blunt glass slide, silvery scales are observed followed by
a glistening transparent membrane
âOn removal of this membrane [Bulkeleyâs membrane] multiple small bleeding points are
observed
âThis sign is absent in pustular psoriasis and inverse psoriasis
âGrattage test
âWhile eliciting the Auspitz sign, the characteristic coherence of scales seen as if one scratches a
wax candle (candle grease sign)
16. Woronoff's Ring
âA blanched halo of approximately uniform width surrounding psoriatic lesions
usually following phototherapy or coal tar therapy
âLocal inability to synthesize PGE2 in response to an ultraviolet light stimulus,
resulting from the presence of an inhibitor of prostaglandin synthesis
18. Morphological Types
âChronic plaque psoriasis:
âMost common form
âAlso known as psoriasis vulgaris
âTypically appears as erythematous plaques covered with silvery white scales
âThe plaques coalesce and cover large areas of skin
âCommon locations include the trunk, extensor surfaces of limbs and the scalp
20. Morphological Types
âGuttate psoriasis:
âGreek word âguttaâ meaning droplet
âCharacterized by numerous small oval (teardrop-shaped) spots distributed in a centripetal
fashion
âAccounts for 2% of the cases
âAssociated with streptococcal (group A) throat infection
âCommon in children, good prognosis
âAbout one third patients develop plaque psoriasis eventually
22. Morphological Types
âPustular psoriasis: Crops of pustules on erythematous base
1. Localized
A. Palmoplantar pustulosis
B. Acrodermatitis continua of Hallopeau
2. Generalized
A. Acute (Von Zumbusch)
B. Of pregnancy
C. Infantile and juvenile
D. Circinate
E. Localized (not hands and feet)
âTrigger factors: Sudden withdrawal of systemic or potent topical steroids,
infections
24. Demographics of Palmoplantar Pustulosis
Differ from Other Types of Psoriasis
âWomen >men (9:1)
âPeak between 40 to 60 years
âStrong association with smoking
25. Morphological Types
âErythrodermic psoriasis: Generalised erythema and scaling (involving >90%
of BSA)
âDevelops from chronic plaque psoriasis or unstable psoriasis precipitated by infections, tar,
drugs or withdrawal of corticosteroids
âAccompanied by fever, chills, hypothermia, and dehydration secondary to the large BSA
involvement
âFollicular psoriasis: Scaly, follicular papules over trunk and extremities
âThese are present at the openings of pilosebaceous follicles
27. Morphological Types
âLinear psoriasis: Linear distribution of psoriatic lesions along Blaschko's lines
âAnnular psoriasis: Clearing in the centre of the plaque
âRupioid (limpet like or cone shaped lesions), elephantine and ostraceous
psoriasis (lesions resembling oyster shells)
âRupoid plaques are small, 2-5 cms in diameter and highly hyperkeratotic, resembling limpet
shells
âOstraceous psoriasis presents with hyperkeratotic plaques with concave
centres similar in shape to oyester shells
28. Distributional Variation
âScalp psoriasis
âPalmoplantar psoriasis
âNail psoriasis: Nails involved in 25-50% patients
âPitting, onycholysis, subungual hyperkeratosis, splinter hemorrhages, the oil-drop sign
âMucosal psoriasis
âInverse psoriasis:
âSpares the typical extensor surfaces
âAffects intertriginous (i.e., axillae, inguinal folds, inframammary creases) areas with minimal
scaling
33. Psoriasis in Children
âCommon in girls
âMore pruritic
âLesions are relatively thinner, softer, and less scaly
âMore frequently precipitated by infections
âFacial involvement more common than in adults
âCertain clinical variants like erythroderma, arthropathy and pustular psoriasis
are rare
34. Psoriasis in HIV
âAcute onset
âMore severe
âRefractory to conventional treatment
âPoor prognosis
35. Psoriatic Arthritis
âSeen in 5-10% of psoriatic patients
âTypes:
âClassic - Distal interphalangeal arthropathy (15%)
âAsymmetrical oligoarticular arthritis (70%)
âSymmetrical polyarthritis - Rheumatoid type (5%)
âPsoriatic spondylitis with or without sacroiliatis (5%)
âArthritis mutilans (5%)
36. âNail associated severity index (NAPSI)
âThe target nail is graded for nail matrix psoriasis and nail bed psoriasis
âThe sum of these two scores is the total score for that nail
âNail matrix changes: Pitting, leukonychia, red spots in the lunula, and nail plate crumbling
âNail bed changes: Onycholysis, splinter hemorrhages, oil drop (salmon patch), nail bed
hyperkeratosis
Scoring Systems in Psoriasis
38. Psoriasis Area and Severity Index
Score Erythema Induration Desquamation
0 Absent Absent Absent
1 Mild Mild Mild
2 Moderate Moderate Moderate
3 Severe Severe Severe
4 Very severe Very severe Very severe
39. Calculation for Intensity
âThe three intensity scores are added for 4 body regions to give subtotals A1,
A2, A3, A4
âEach subtotal is multiplied by body surface area represented by that region
âA1 x 0.1 gives B1
âA2 x 0.2 gives B2
âA3 x 0.3 gives B3
âA4 x 0.4 gives B4
40. âThe percentage area affected by psoriasis is evaluated in 4 regions of the
body (head and neck, upper limbs, trunk, lower limbs)
Score Area
0 nil
1 1-9%
2 10-29%
3 30-49%
4 50-69%
5 70-89%
6 90-100%
41. âEach body area score is multiplied by area affected
âB1 x (0-6) = C1
âB2 x (0-6) = C2
âB3 x (0-6) = C3
âB4 x (0-6) = C4
âPASI Score = C1 + C2 + C3 + C4
42. Histopathology
âParakeratosis
âMicro abscesses of Munro in the horny layer
âAbsence of granular layer
âRegular elongation of rete ridges (camel-foot shaped)
âSupra papillary thinning
âSpongiform pustules of Kogoj
âDilated and tortuous capillaries in dermal papillae
âSuperficial perivascular inflammatory infiltrate
45. Management of Psoriasis
âPsoriasis is a chronic disease that can have a significant effect on quality of
life
âManagement involves addressing both psychosocial and physical aspects of
the disease
âPsychosocial aspects:
âLaying out reasonable aims of treatment
âPatient education
âCounselling and/or treatment with psychoactive medications
46. General Measures
âAvoidance of trauma or irritating agents
âWeight reduction in obese patients
âReduce intake of alcoholic beverages
âReduce emotional stress
âSunlight and sea bathing improve psoriasis except in photosensitive
47. Topical Therapy
âEmollients
âMinimize the symptoms of itching and
tenderness
âHelp prevent irritation and thus the
potential for
â Subsequent Koebnerization
âTar
âAntiproliferative effect
â2% or 3% crude coal tar
âAlternative is 4 to 10% LCD (liquor
carbonis detergens, a tar distillate)
48. Goeckerman Regimen
âGoeckerman regimen: Coal tar is applied on inâpatient basis for 24 h in
combination with sub erythemogenic doses of UVB
âModified Goeckerman regimen using coal tar applied for 5 h/day in
combination with narrowâband UVB (NBUVB) in patients with moderate to
severe psoriasis
49. Topical Therapy
âAnthralin
âMay restore normal epidermal
â Proliferation and keratinization
âStains clothes, irritant
âIngram regimen: Inâpatients are treated with a tar bath, sub
erythemogenic UVB and then dithranol in Lassarâs paste applied to
plaques, starting at a concentration of 0.05â0.1% and increased
cautiously to reduce irritation up to a maximum concentration of 4%
âSalicylic acid
âKeratolytic agent
âAdjuvant to other topicals
50. Topical Therapy
âTopical corticosteroids
âMainstay of topical treatment especially for plaque psoriasis
âAnti-inflammatory, antiproliferative, and immunosuppressive actions
âCan be used as monotherapy 1-2 times daily or combined with other topical agents
âTopical vitamin D analogues
âInhibition of keratinocyte proliferation and enhancement of keratinocyte differentiation
âCalcipotriene, calcitriol, tacalcitol, maxacalcitol, becocalcidiol
51. Topical Therapy
âTopical retinoids
âTazarotene (0.05%/0.1%)
âAct by normalizing abnormal keratinocyte differentiation, diminishing hyperproliferation and by
decreasing expression of inflammatory markers
âCalcineurin inhibitors
âTacrolimus/pimecrolimus
âAct by blocking the synthesis of numerous inflammatory cytokines
âFacial and intertriginous psoriasis
52. UVB Phototherapy
âIndication
âGeneralized psoriasis unresponsive to topicals
âNarrow band UVB is not only more effective than broad band UVB but also leads to rapid
clearance of lesions
âDosage:
âInitial dosing according to skin type (130-400 mJ/cm2) or MED (50% of MED) [MED = minimal
erythema dose]
âSubsequent dosage increase by 15-65 mJ/cm2 or â¤10% of initial MED
âTreatment 3-5 times/week
53. UVB Phototherapy
âDuration of treatment
âResponse observed at 8-10 treatments
âSingle course is 15-20 treatments
âMaintenance therapy may prolong remission
54. Combination of UVB with Systemic Therapies
âMethotrexate with UVB therapy has shown potential value because of the
synergistic effects of these two therapies
âRetinoids with UVB have been extensively studied and accelerate the
response to phototherapy, reducing the cumulative dosage of UVB and the
dose of acitretin required to achieve psoriasis clearance
55. Targeted Phototherapy
âExcimer lasers/lamps and targeted UVB therapy selectively target affected
lesions of psoriasis while leaving unaffected skin untreated
âHighly effective, can be used for resistant localised lesions such as scalp and
palmoplantar psoriasis
56. PUVA Photochemotherapy
âSystemic psoralen plus ultraviolet A is indicated for adults with generalized
psoriasis who are resistant to topical therapy
âContraindicated in patients with known lupus erythematosus, porphyria, or
xeroderma pigmentosum
âDosage:
â8-Methoxypsoralen, 0.4-0.6 mg/kg
âTaken 1-2 hours before exposure to UVA
âOther available forms of psoralen include 5-methoxypsoralen and trimethylpsoralen
âUV protective eye wear should be worn when outdoors for 12 hours post-ingestion
âTreatment 2-3 times/week
57. PUVA Photochemotherapy
âDuration of treatment:
âInitial improvement frequently seen within 1 month of therapy
âSingle course is 20-25 treatments
âMay be repeated as indicated
âTopical PUVA therapy
âTopical PUVA is indicated for adults with psoriasis of palms and soles
âBath PUVA is indicated for adults and children with generalized psoriasis
58. Combination of PUVA with Other Therapies
âCombination of topical calcipotriol with PUVA leads to a decrease in duration
of PUVA therapy along with an improved clinical response
âCombination of oral retinoids with PUVA is more effective compared with
monotherapy with either acitretin or PUVA alone
âBecause patients who have previously received PUVA treatment have an
increased risk for developing SCC when subsequently treated with
cyclosporine, this combination should be avoided
âPUVA with MTX - safety questioned
59. Systemic Therapy
âGeneral principles
âA BSA of 10% has been traditionally used as a prerequisite to start a systemic therapy
âHowever, a subset of patients with limited disease having debilitating symptoms with significant
negative affect on quality of life of patient makes a systemic approach to treatment
appropriate
60. Methotrexate
âIndication:
âSevere, recalcitrant, disabling psoriasis that is not adequately responsive to other forms of
therapy
âDosing:
âWeekly single oral dose total dose should not ordinarily exceed 30 mg/week
âA test dose of 2.5-5 mg is recommended
âFolate supplementation
61. Apremilast
âPhosphodiesterase 4 inhibitor
âNew oral agent for the treatment of moderate to severe plaque psoriasis and
psoriatic arthritis
âAdvantages include its oral administration, and it is anti-inflammatory rather than
immunosuppressant
âFavourable safety profile, laboratory monitoring is not required and a potentially
advantageous weight loss effect
âGastrointestinal intolerance is the most common adverse effect â diarrhoea (18%)
and nausea (17%)
âApremilast has potentially been associated with an increased risk of depression,
although the incidence is low â caution and close monitoring is advised in patients
with a history of depression
62. Cyclosporine
âIndication:
âAdult, non immunocompromised patients with severe, recalcitrant psoriasis
âEfficacy observed in erythrodermic psoriasis, generalized pustular psoriasis, and palmoplantar
psoriasis
âDosing:
â2.5-5.0 mg/kg/d in two divided doses/day
63. Acitretin
âIndication:
âAdults with severe plaque type psoriasis (FDA approved)
âRapid and impressive responses seen in patients with pustular psoriasis
âBecause of a lack of significant immunosuppression, acitretin is generally
considered effective and the treatment of choice in HIV-positive patients
with severe psoriasis
âDosing:
â10-50 mg/day given as a single dose
âEfficacy rates when used in combination with phototherapy are higher
64. Second Line Systemic Agents
âAzathioprine: Due to absence of data from controlled trials, it is best to
conclude that there is no good evidence that azathioprine is an effective
treatment for psoriasis
âFumaric acid esters: Several well-designed randomized studies of fumarates
demonstrate mean PASI improvement rates of between 50% and 80% after 12
to 16 weeks of treatment
âHydroxyurea: May be a valuable reserve drug for patients needing systemic
treatment and who are resistant to methotrexate or develop side effects
âLeflunomide: May be used in patients of psoriasis with arthritis
65. Second Line Systemic Agents
âMycophenolate mofetil: Therapy of severe psoriasis probably in combination
with cyclosporin as a cyclosporin sparing agent
âSystemic steroids:
âNot to be used in the routine care of psoriasis
âRole in the management of persistent, otherwise uncontrollable erythroderma that is causing
metabolic complications
âGeneralized pustular psoriasis of the Von Zumbusch type if other drugs are contraindicated or
ineffective
âSteroids may occasionally be needed, and in high dosage to control hyperacute polyarthritis
67. Biologic Agents
âBiological's use should be restricted to:
âPatients with severe disease defined by a PASI score of 10 or more (or BSA of 10% or greater
where PASI is not applicable) and DLQI of greater than 10
âPatients who have failed to respond to, or who have a contraindication to, or who are
intolerant to other systemic therapies such as cyclosporin and methotrexate
68. Biologic Agents
âBiological agents licensed for treatment of psoriasis vulgaris
âEtanercept, a fully human soluble p75 TNF-Îą receptor fusion protein
âInfliximab, a chimeric human-immune antibody to TNF-Îą
âAdalimumab, a fully human recombinant antibody to TNF-Îą
âUstekinumab, a fully human recombinant antibody to the p40 component of IL-12/IL-23
âAlefacept, a fusion protein of lymphocyte function associated antigen-3 and IgG that inhibits T-
cell activation
âSecukinumab, an anti-IL-17A monoclonal antibody
69. Biologic Agents
âInfliximab is administered by IV infusion while the others are
administered by SC injection
âBiological agent of choice
âFor stable disease, particularly if not too severe (e.g., PASI >10
but <20) etanercept or adalimumab
âFor patients requiring rapid disease control
adalimumab or infliximab
âFor patients with unstable or generalized pustular psoriasis
severe nail disease infliximab
âUstekinumab should be reserved for use as a second-line biological
agent