EczemaEczema

EczemaEczema Is a pattern of cutaneous inflammatory responseIs a pattern of cutaneous inflammatory response

characterized characterized clinicallyclinically by : itching , redness , weeping in its by : itching , redness , weeping in its acuteacute form form

and by : dryness , lichenfication in its and by : dryness , lichenfication in its chronicchronic form form and characterized and characterized histologicallyhistologically by by: :

11 - -lymphocytic infiltratelymphocytic infiltrate 22 - -spongiosis ( intercellular edema )spongiosis ( intercellular edema )

33 - -varying degrees of acanthosis ( increased thickness of epidermal layer )varying degrees of acanthosis ( increased thickness of epidermal layer )..

ClassificationClassification: : 11 - -endogenousendogenous ( constitutional type) ( constitutional type): :

a- atopic eczema ( dermatitis)a- atopic eczema ( dermatitis) b- seborrhoeic eczema (dermatitis)b- seborrhoeic eczema (dermatitis)

c- discoid eczemac- discoid eczema d- d- pompholyxpompholyx

e- stasis eczemae- stasis eczema 22 - -exogenous exogenous eczema (contact dermatitis)eczema (contact dermatitis)::

a- irritant contact dermatitisa- irritant contact dermatitis b- allergic contact dermatitisb- allergic contact dermatitis

33 - -unclassifiedunclassified : : a- neurodermatitis ( lichen simplex chronicus)a- neurodermatitis ( lichen simplex chronicus)

b- juvenial planter dermatosisb- juvenial planter dermatosis

Atopic Dermatitis ( Eczema)Atopic Dermatitis ( Eczema)AtopyAtopy: is a genetically determined disorder in which: is a genetically determined disorder in which : :

11--there is increased liability to form IgE antibodiesthere is increased liability to form IgE antibodies 22--there is an increased tendency to have : asthma , hay fever & atopic dermatitisthere is an increased tendency to have : asthma , hay fever & atopic dermatitis

PrevalencePrevalence: : 10-20%10-20% of the population are affectedof the population are affected. .

AetiologyAetiology:: 11 - -Definite aetiology are not well determinedDefinite aetiology are not well determined

22 - -AD patients usually have AD patients usually have highhigh level of IgE antibodies to ( house dust mites ) level of IgE antibodies to ( house dust mites ) 33 - -foods clearly exacerbate symptoms in some atopic patients especiallyfoods clearly exacerbate symptoms in some atopic patients especially

children . children . EggsEggs , , nuts ,cows milknuts ,cows milk represent 75% of positive food allergies represent 75% of positive food allergies. . 44 - -exacerbation also occurs after : immunization , viral infections ,in winterexacerbation also occurs after : immunization , viral infections ,in winter . .

55 - -worsening factors : a- cloths irritationworsening factors : a- cloths irritation b- allergens of airb- allergens of air

c -excessive washingc -excessive washing d- excessive rubbingd- excessive rubbing

Clinical stagesClinical stages: :

1- AD pass into clinicohistological evolution fromAD pass into clinicohistological evolution from: : acute eczematous eruption in early life intoacute eczematous eruption in early life into

chronic lichenified dermatitis in older patientschronic lichenified dermatitis in older patients. . 2 -AD can be divided into can be divided into 33 stages ( according to the onset ) stages ( according to the onset ): :

aa- infantile AD 2 mns - 2 yrs- infantile AD 2 mns - 2 yrs bb- childhood AD 2 yrs - 12 yrs- childhood AD 2 yrs - 12 yrs

cc- adolescent and adult onset AD- adolescent and adult onset AD

Clinical featuresClinical features: :

• * *in infancyin infancy presented ( mostly after 2 mns of age )as itchy , presented ( mostly after 2 mns of age )as itchy , erythema of cheeks , in these patches ,fine vesicles develop, rupture erythema of cheeks , in these patches ,fine vesicles develop, rupture

and produce moist crusted areas ( i.e. acute moist lesions ) and produce moist crusted areas ( i.e. acute moist lesions ) . .• Other sites : scalp, neck, extensor extremities , but diaper area Other sites : scalp, neck, extensor extremities , but diaper area

spared spared. .

* *in childhood ADin childhood AD , usually less exudative , drier , slightly scaly plaques , usually less exudative , drier , slightly scaly plaques involving : eyelids and face , antecubital fossae , popliteal fossae involving : eyelids and face , antecubital fossae , popliteal fossae

* *adult ADadult AD : localized erythematous scaly papulovesicular plaques or : localized erythematous scaly papulovesicular plaques or chronic lichenified plaques, involving same sites of childhood AD chronic lichenified plaques, involving same sites of childhood AD . .

DiagnosisDiagnosis: : It is based on major and minor criteria and the diagnosis must beIt is based on major and minor criteria and the diagnosis must be: :

33 majors + majors + 33 minors minors

Major criteriaMajor criteria::

11 - -prurituspruritus

22 - -typical morphology &distributiontypical morphology &distribution: : a- flexural lichenification in children and adultsa- flexural lichenification in children and adults. .

b- facial &extensor involvement in infancyb- facial &extensor involvement in infancy. .

33 - -chronic or chronically relapsing dermatitischronic or chronically relapsing dermatitis. .

44 - -personal or family history of atopic disease ( asthma , alleric personal or family history of atopic disease ( asthma , alleric rhinitis , atopic dermatitis) rhinitis , atopic dermatitis)

Minor criteriaMinor criteria: :

11 - -xerosis ( dryness )xerosis ( dryness ) 22 - -hyperlinear palmshyperlinear palms

33 - -increased serum IgEincreased serum IgE 44 - -tendency for cutaneous infection especially (staph.aureus & HSV)tendency for cutaneous infection especially (staph.aureus & HSV)..

55 - -tendency for non specific hand /foot dermatitistendency for non specific hand /foot dermatitis 66 - -chelitis ( inflammation of lips)chelitis ( inflammation of lips)

77 - -Dennie-Morgan infraorbital folds (> 2 folds )Dennie-Morgan infraorbital folds (> 2 folds ) 88 - -orbital darkeningorbital darkening

99 - -facial pallorfacial pallor 1010 - -pityriasis albapityriasis alba

1111 - -perifollicular accentuationperifollicular accentuation 1212 - -post auricular fissuringpost auricular fissuring

1313 - -Hertoghe sign (thinning of lateral part of eyebrows)Hertoghe sign (thinning of lateral part of eyebrows) 1414 - -white dermographismwhite dermographism

Immunopathology of AD:

**It is a T-helper type (It is a T-helper type (Th2 dominanceTh2 dominance ) in tissues ) in tissues.. Th2 produce Th2 produce IL4IL4 , 5, 5 , ,1010

**IL4 leads to IL4 leads to elevated IgEelevated IgE & & oesinophiliaoesinophilia in tissues &peripheral blood in tissues &peripheral blood. .

* *IL10 will inhibit cellular immunityIL10 will inhibit cellular immunity

• So , there is tendency towards So , there is tendency towards humeral immunityhumeral immunity..

* *Langerhans cells in skin ( Ag presenting cell in skin ) are abnormalLangerhans cells in skin ( Ag presenting cell in skin ) are abnormal ) ) directly stimulate Th cells without Ag in the way of Th2 phenotypedirectly stimulate Th cells without Ag in the way of Th2 phenotype((

Differential Diagnosis: Infantile AD should be differentiated from seborrhoeic dermatitis in infancyInfantile AD should be differentiated from seborrhoeic dermatitis in infancy

because of similar presentations .However , it can be differentiated bybecause of similar presentations .However , it can be differentiated by: :

Atopic DermatitisAtopic Dermatitis Seborrhoeic DermatitisSeborrhoeic Dermatitis

11-- age of onsetage of onset : : afterafter 2 months2 months22 - -Hx and examHx and exam: .: .

infant is irritable due to itchinginfant is irritable due to itching weepy erythmatosquamous weepy erythmatosquamous

lesions involving cheeks , lesions involving cheeks , extensors (sparing napkin extensors (sparing napkin area)area). .

33 - -Milk Crust over scalpMilk Crust over scalp 44 - -increased serum IgEincreased serum IgE

55 - -prognosis is unpredictableprognosis is unpredictable. .

11 - -age of onset : age of onset : before 2 monthsbefore 2 months 22 - -Hx and examHx and exam::

infant is calminfant is calm greasy erythematosequamous greasy erythematosequamous

lesions involving cheeks , lesions involving cheeks , eyebrows , neck, flexors eyebrows , neck, flexors , napkin area , axillae , napkin area , axillae ( i.e. intertriginous areas)( i.e. intertriginous areas). .

33 - -Cradle cap on scalpCradle cap on scalp 44 - -normal serum IgEnormal serum IgE

55 - -prognosis is excellentprognosis is excellent. .

Treatment: 1 -General measuresGeneral measures : avoidance of: excessive bathing ( or washing )

extremes of cold and heat , emotional stress , vigorous rubbing.

2 -Specific measuresSpecific measures: :

A- Topical Rx : * drying agentdrying agent : e.g. K+ permanganate for weeping lesions.

* emollientsemollients : for hydration of dry skin e.g. Vaseline ointment and Zinc Oxide ointment.

* topical steroidstopical steroids :( moderate to potent ) are very beneficial * topical calcineurine inhibitorstopical calcineurine inhibitors : (tacrolimus ointment)

B- Systemic Rx : 1 -antihistamine : to control pruritus and give sedation

2 -systemic corticosteroids to control acute and severe cases 3 -Phtotherapy are often helpful for severe AD

- PUVA for older patients - UVB for older and younger patients