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INTRODUCTION
chronic, inflammatory and proliferative conditions
of the skin
CHRONIC PLAQUE PSORIASIS
INCIDENCE AND PREVALANCE
1-2% of indian population
ETHINICITY
white people.
GENDER
M=F
EPIDEMIOLOGY
AGE AT ONSET
Bimodal peak
16 and 22 years 57 and 62 years
Type I Type II
Hereditary, strongly HLA associated
(particularly HLA‐C:06:02),
early onset and more likely to be severe.
Sporadic, HLA unrelated,
of late onset and often mild.
ETIOLOGY
• GENETICS- HLACW-6
• ENVIRONMENTAL –
• Infections- streptococcus, HIV
• Drugs- lithium antimalarials
• Stress
• Alcohol
• Smoking
• Sunshine
• Physical trauma
PATHOGENESIS
•Th1 Response
Presentation
•Well demarcated
•Erythematous
•Scaly ( silvery white scales)
•Indurated
•Plaques
•Extensors
•Always look for lesion on scalp and genitalia and nail
•Ring of woronofff may be present
•Koebners phenomenon may be seen
NAIL CHANGES
•pitting
•Salmon patch
•Oil drop
•Subungual hyperkeratosis
•Leuconychia
•Distal onycholysis
•Splinter haemarrhages
Clinical variants of psoriasis
Acute guttate psoriasis
• Sudden onset of a shower of small lesions, It is more common in
children and young.
• It frequently follows several weeks after phanyngitis caused by group A
streptococci
Unstable psoriasis
Recognized precipitants for unstable psoriasis
•Withdrawal of systemic or potent topical corticosteroids
•Treatment with irritants such as tar or dithranol
•Acute infection
•Hypocalcaemia
•Severe emotional upset.
Erythrodermic psoriasis
•Psoriasis - The underlying cause in about 25% of
cases of erythroderma .
PUSTULAR PSORIASIS
•Acute generalised pustular psoriasis ( von zumbusch disease)
•Impertigo herpetiformis ( pregnancy)
•Localised palmoplantar pustulosis
•Acrodermatitis continuaof hallopeau
•DOC – ACITRETIN except impetigo herpetiformis where oral steriods
given
Complications and comorbidities
•Stress
•Other autoimmune disorders like IBD,Vitiligo
•Metabolic syndrome
•Malignancy because of chronic inflammation
•Hepatobiliary disease- non alcoholic fattyliver
CLASSIFICATION OF SEVERITY
•The PASI ( psoriais area and severity index)
•Erythema, scaling and induration are graded in each region
each with a score 0-4.
Bed side tests
•Grattage test and Auspitz sign
•Scrape the lesion with slide. The scales gets
accentuated. On further scraping. Reddish membrane
appears which is called as Berkley's membrane. On
removal of this pin point bleeding appears.
Histopathology
•Hyperkeratosis
•Parakeratosis
•Hypogranulosis
•Elongation of rete ridges
•Munroes microabscess
•Spongiform pustules of kogoj
•Suprapapillary thinning
•Dialted and tortous bvessels
•Screening for co morbities
MANAGEMENT
•GENERAL- weight reduction
•Stop smoking alcohol
•Address comorbities
TOPICAL
•Topicalsteriods
•Topicaltacrolimus
•Topicalvitamin D analogues
•Coaltar
•Dithranol
•topicalretinoids
PHOTOTHERAPY
•NB-UVB
•PUVA
SYSTEMIC
•Methotrexate
•Acitretin
•Cyclosporin
•Others- fumaric acid esters, hydroxyurea
NEW DRUGS
Apremilast - inhibitor of phosphodiesterase 4,
Tofacitinib oral inhibitor of Janus kinases JAK1 and JAK3
Ponesimod modulator of the sphingosine‐1‐phosphate
receptor (S1PR1).
BIOLOGICALS
•TNF‐α inhibitors
(Infliximab,Etanercept,Adalimumab)
•IL-12/IL-23 P40 INHIBITORS Ustekinumab
•IL-17 INHIBITORS(BRODALUMAB,IXEKIZUMAB
,SECUKINUMAB)
PSORIATIC ARTHRITIS
seronegative inflammatory arthritis, which occurs in up to 40% of patients
with moderate to severe psoriasis.
CASPAR (Classification Criteria for Psoriatic Arthritis) criteria, with 99%
sensitivity and 91% specificity .
1. peripheral mono‐ or asymmetrical oligo‐arthritis, predominantly affecting
the distal interphalangeal joints,
2. symmetrical rheumatoid‐like pattern,
3. arthritis mutilans (a rare severe deforming arthritis of the hands and feet)
4. axial disease with spondylitis and/or sacro‐iliac disease.
5. Dactylitis
• Asymmetric oligo‐arthritis is the commonest variety followed by symmetric
polyarthritis.
• Clinical features
• Symptoms of inflammatory joint disease (early morning stiffness and joint
swelling) .
• Early morning back stiffness
• Heel pain (a manifestation of enthesitis of the Achilles tendon) or plantar fasciitis
• Clinical examination may reveal evidence of dactylitis (sausage fingers) or
swollen or tender joints.
• . The nail changes of psoriasis will be present in up to 80% of patients.
TREATMENT

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Psoriasis