Sarajan, Aldilyn J

• Papulosquamous diseases are a group of disorder xtized by scaly plaques and papules.

• It includes:• psoriasis• Lichen planus

• Introduction• Epidemiology• Aetiology• Pathophysiology• Clinical feature • Differential diagnosis• Investigation• Treatment

• Psoriasis is a chronic non-infectious inflammatory skin dx caused by abnormally fast turnover of the epidermis.

• It is a papulosquamous lesion that is characterised by erythematous plaque and silvery scale.

• Is a major problem in the temperate especially Europe&north America.

• However the incidence is on increase in the tropics

• Females and males are equally affected.• Peak incidence in 2nd decade of life and 5th decade

of life.

• Is unknown.• Genetics –affected relatives,concordance rates of

70% in identical twins, hla association• Immunopathological-il-(1,2,6,8),IFN,TNF.• Precipitating factors

include:trauma,infection,stress and drugs e.g b-blockers,lithium,antimalaria

• 2 key abnormalities-hyperproliferation of keratinocytes and

• inflammatory cell infiltration• Explanation of the pathophysiological process is

highly controversial• Some theories say that the abnormality is a

genetic defect in the control of keratinocytes(IFN-y)

• Some theories suggest that the hyperproliferation causes the inflammation,and vice versa

Depends on the clinical types;[1]stable plaque psoriasis:

commonest,individual lesion is demarcated ,red with dry silvery-white scale.tha site of predilection are the elbow,knee,and lower back.in some cases,the scalp is involved.involvement of nail is characterised by thimble pitting,onycholysis and subungual hyperkeratosis.flexure involvement include natal cleft,submammary and axillary fold{red,shiny,symmetrical and non-scaly}.koebner ‘s phenomenon

• [2]guttate psoriasis:common in children and adolescence,follows streptococcal sore throat.individual lesion is droplet shaped, small(1cm),and scaly.

• [3]erythrodermic psoriasis:• here,the skin becomes universally red with

little scale.

• [4]pustular psoriasis:• ass with swinging pyrexia, commonly found

in immunosuppressed state

I. Discoid eczema-not well defined,itchy,doesn’t favour scalp,extensor aspects.

II. Seborrheic eczema-diffuse,less lumpy,less defined.

III. Pityriasis rosea-herald plaque may preceed the rash.

IV. Tinea ungium-no pitting.V. Secondary syphilis-lesions are browny,patchy

alopecia,lymphadenopathy.

• Psoriartic arthropathy-involves the terminal interphalangeal jts of fingers toes.

• Throat swab.• Skin scrapings &nail clips.• Rheumatoid factor test.• VDRL test.

• Counselling• Topical treatment:

dithranol,coaltar,calcipotriol,corticosteroids• Ultraviolent therapy:UVB,PUVA• systemic tx:methotrexate,oral retinoids,cyclosporin.

• Is a non infectious immunological mediated skin disorder.

• It is a disorder in which lymphocytes attack the epidermis.

• It can be associated with autoimmune disorders such alopecia areata, ulcerative collitis.

• It is unknown.• Drugs can cause it-

streptomycin,chloroquine,levamisole,methyldopa,phenothiazine.

• It has also been linked to glucose intolerance,bone marrow transplant,hepatitis B infection,exposure to colour film in colour film developers.

• Typical itchy papules, demarcated by skin lines on the extremeties especially the volar aspects.

• White streaky pattern on the surface of the papules (wickham’s striae).

• It occurs on joint flexures especially the wrists, genitals, inner thighs.

• Koebner’s phenomenon is also present.• Neighbouring papules may join together to form

plaques that resembles lichen growing on trees.• White lacy plaques in the mouth.

• Annular –area of central clearing.• Atrophy-in mucous membrane.• Bullous• Follicular• Hypertrophic –around the ankles.• Ulcerative-on soles and mucous membrane.

• It is a self limiting disorder in which individual lesions lasts for months and the eruption as a whole tends to last for about a year.

• As lesions resolve, they become flatter, darker and leave discrete brown macules.

• Nail and hair loss may be permanent.• Ulcerative form in the mouth may lead to

squamous cell carcinoma.• Ulceration over bony prominences may be

disabling.

• Lichenoid drug reactions-antimalaria, NSAIDS, PABA,b-blockers.

• Discoid lupus erythematous-wickhams’s striae or oral lesions are absent.

• Oral candidiasis.• Gold and heavy metals reaction.

• Diagnosis is usually obvious clinically,but a biopsy can confirm the diagnosis if necessary.

• Histology-hyperkeratosis,focal hypergranulosis,thickening of the epidermis(saw toothed appearance),separation btw dermis and epidermis.

• Stop offending agent.• Anti-histamines..• Potent topical corticosteroids-to relieve the

symptoms&flatten the plaques.• Uv radiation-reduce pruritus,help clear the lesions.• Systemic corticosteroids-prednisolone 40-60mg

4-6x/dy for 3mths.