DR ISRAEL G.M

FWACP

Overview of the Eczemas

outline

Definition

Classification

Epidemiology

Pathogenesis

Pathology

Clinical features

AD,SD,CD etc

Investigation and treatment

Definition

Eczemas are Inflammatory skin disease characterised by

spongiosis with varying levels of acanthosis, and superficial

perivascular lympho-histiocytic infiltrates.

Eczema is a Greek word that literally means “to boil over”

May be used interchangeably with dermatitis

Classification

Exogenous eczemas - Clearly defined external trigger factors

+ inherited tendencies

Endogenous eczemas - mediated by processes originating

within the body, No environmental factor.

Combination of both – eg Hand eczema: primarily

endogenous+ aggravated contact irritants e.g. detergents

Classification

Acute Eczema - histological picture is dominated by

spongiosis and vesicle formation

Subacute Eczema- Spongiosis and vesiculation diminish and

acanthosis increases.

Chronic Eczema - Hyperkeratosis coexists with areas of

parakeratosis. Spongiosis and vesiculation give rise to

acanthosis.

Endogenous eczemas

Atopic dermatitis

Seborrhoeic dermatitis

Asteatotic eczema

Discoid eczema

Pityriasis alba

Hand eczema

Stasis eczema

Eczematous drug eruptions

Epidemiology

Numerous studies of the prevalence of atopic AD

Fewer in other eczemas.

USA, a study examined 20,000 people ; 1/3rd had significant skin pathology.

Prevalence of all forms of eczema was 18 /1000

7/1000 was AD

Hand eczema, dyshidrotic eczema and nummular eczema each accounted for

about 2 per 1000

Eczema and age

Most cases of eczema in infants and young children are AD

Perioral eczema or lick eczema - children with atopic eczema

SD of infancy and napkin dermatitis

Pompholyx & AD - less common in elderly people

Discoid eczema - elderly males

irritant hand eczema – factory worker, Gardners/ Farmers

Pathogenesis

There has been considerable research on the pathogenesis of

some types of eczema, particularly:

Allergic contact dermatitis

Primary irritant dermatitis

Atopic dermatitis

Pathology Varies depending on intensity & stage of

eczematous process

Modified by secondary events such as trauma or

infection

Features

Spongiosis – intercellular epidermal oedema → vesicles

Infiltration of epidermis by lymphocytes

↑ epidermal mitotic activity → acanthosis

Vascular dilatation in dermis in all stages with lympho-

histiocytic infiltrate

Pathology

Secondary changes

Superficial erosions, haemorrhage & sub-epidermal fibrinoid

changes from trauma (rubbing or itching)

Secondary infection → sub-cornual pustules

Pathology

The epidermis shows distinct vesicle formation. Acute eczema.

ATOPIC ECZEMA

Atopic dermatitis (AD) is a pruritic disease of unknown

origin

Starts in early infancy

Adult-onset variant is recognized

Characterized by:

-Pruritus

-Eczematous lesions

- Xerosis

-Lichenification (Skin thickening +↑ markings)

ATOPIC ECZEMA

Associations

↑ IgE–associated diseases

Acute allergic reaction to foods

Asthma

Urticaria

Allergic rhinitis

Aetiology Heredity

Family hx in 70% of cases

Gene of predisposing to atopy -11q13

Immunological abnormalities

↑ IgE

Predisposition to anaphylaxis

Dysregulation of cytokine mediation

EpidemiologyCourse

85% -1st year

95% < 5 years.

Incidence highest in infancy &childhood.

Complete remission in adolescence

Recur in early adult life.

Clinical featuresAge dependent

Babies

itchy, vesicular exudative rash on face & hands

Extensor involvement

Childhood

flexural involvement

erythema of face

infra-orbital folds (Dennis Morgan’s fold)

lichenification, excoriations & dry skin

palmar hyper-linearity

Adults

Hand dermatitis

More extensive involvement in a small percentage of people

Clinical features Adult onset

Lesion becomes more diffuse and erythematous

The neck may be involved- dirty neck sign (not always present)

Lichenification may be present

Clinical features

Hanifin and Rajka criteria

Major criteria

Pruritus

Dermatitis affecting flexural surfaces in adults and the face

and extensors in infants

Chronic or relapsing dermatitis

Personal or family history of cutaneous or respiratory atopy.

PLUS 3 or more Minor criteria

Clinical features Minor criteria

Facial features:

facial pallor

facial erythema

hypopigmented patches

infraorbital darkening

infraorbital folds (Dennie-Morgan folds)

cheilitis

recurrent conjunctivitis

anterior neck folds.

Triggers:

foods

emotional factors

environmental factors

skin irritants.

Clinical features Minor criteria

Complications: Susceptibility to cutaneous infections

Impaired cell-mediated immunity

Imediate skin-test reactivity

Elevated IgE

Keratoconus

Anterior subcapsular cataracts.

Others: Early age of onset

Dry skin

Ichthyosis Hyperlinear palms

Keratosis pilaris,

Hand and foot dermatitis

Nipple eczema,

White dermatographism

perifollicular accentuation.

Treatment EducationKeep nails short

Reduce trigger factorsBody care products Soaps, perfumes, etc

Clothes Fabrics - cotton vs wool, silk, synthetics

Washing – detergents, new clothes

Allergen reduction in environment Pets

Floors – rug vs tiles

Occupation

Avoid contact with herpes pts

Treatment Moisturization in atopic dermatitis

Petrolatum

Corticosteroid

Immunomodulators egTacrolimus, pimecrolimus,

Monoclonal antibody (Omalizumab )-blocks IgE function

Probiotics - subject of research

UV-A, UV-B

Methotrexate, azathioprine , mycophenolate mophetil etc

Anti histamine

Complications Psychosocial dysequilibrium

Retarded growth

Bacterial infections

Viral infections → Kaposi’s varicelliform eruption HSV → eczema herpeticum Vaccinia → eczema vaccinatum

Ocular abnormalities Dennie-Morgan’s fold Conjuctival irritation Keratoconus Cataract

Ichthyosis vulgaris

Seborrheic Dermatitis This is a chronic dermatitis that is characterized : orange red sharply marginated lesions greasy-looking scales Distribution in areas with a rich supply of sebaceous glands: scalp,

face and upper trunk

Associated with overgrowth of Malassezia furfur (P. ovale)

More and extensive in HIV patients

Males > females

A complication of Parkinson’s dse

Rx with levodopa ↓ seborrhoea and improves

Clinical patterns Infantile

cradle cap

Flexures

napkin area

Adult

Scalp

Dandruff

Inflammatory—may extend onto non-hairy areas (e.g.

postauricular)

Clinical patterns Adult CT

Face (Blepharitis & conjunctivitis)

Trunk

Pityriasiform

Flexural

Eczematous plaques

Follicular

Generalized (may be erythroderma)

Treatment Antifungals shampoos - selenium sulfide, 2% Ketoconazole, 1%

terbinafine

Antifungal creams – ketoconazole, other imidazoles

Oral antifungals – itraconazole (21 day course) less toxic than ketoconazole

SSA

Mild steroids – 1% hydrocortisone

Other Rx – benzoyl peroxide, 5% lithium

Recalcitrant cases

UVB therapy

Systemic steroids

Isotretinoin

Post inflammatory SD

Napkin Rash

Infantile SD

Venous stasis dermatitis

Venous stasis dermatitis is an itchy rash in the lower limbs.

Asso with venous dx- ‘gravitational eczema’.

Varicose veins and DVT.

Back pressure develops and fluid accumulate in the tissues.

Venous stasis dermatitis

Gravitational eczema Gravitational ulcer

Dyshidrotic eczema (Pompholix)

Pompholyx

Eczema affecting the hands cheiropompholyx

Feet -pedopompholyx

It is also known as vesicular eczema of the hands and/or

feet.

Pompholix Acute stage Tiny buried vesicles deep in the skin of the palms, fingers, instep or

toes. intensely itchy or burning Mild – peeling Severe- big blisters and cracks

chronic stage scaling cracking crusting.

Aggravated by contact with irritants- water, detergents and solvents

PompholyxTreatment

Cool compress – pottassium permanganate

Topical steroid

Sytemic steroid

Botulinum toxin (prevent sweating)

PUVA therapy

Methotrexate etc

Hand dermatitis-Pompholyx

Contact Dermatitis Dermatitis precipitated by an exogenous agent, often a

chemical

2 major mechanisms

1. Irritant

everybody susceptible

May occur on 1st contact

Depends concentration of chemical & duration

2. Allergic

Prior contact necessary

Immunologically mediated (delayed type IV rxn)

CONTACT DERMATITIS

Plant allergy - toxicodendron

Metal allergy 10% adult females (nickel)

earlobes (earrings)

Neck (chain)

wrist (watch strap)

Lower abdomen (jeans stud).

Perfume or preservative allergy Axillae (deodorant)

Face (moisturiser)

Hands (numerous household products)

Footwear allergy Chrome used to tan leather,

Adhesive used in shoes, rubber

Medicament allergy (e.g. neomycin ointment)

Rubber antioxidant allergy -Thiuram in rubber gloves Latex - contact urticaria or rarely anaphylaxis.

Contact dermatitis Take good history necessary

Link site of body with possible items that could come in

contact with such areas

Patch testing necessary

Treatment is to exclude offending allergen from environment

Other management for eczema

IRR

Patch testing

Management

Protection from irritants and allergens

Emollient barrier cream before, during and after exposure to

irritants

Topical corticosteroids

Antibiotics

In chronic cases- patch testing to identify contact allergies.

Pityriasis alba Pityriasis alba is a mini-form of eczema

Predominantly -infants, children and adolescents.

Multiple hypopigmented patches with fine scalings

Location: face and/or trunk, extremities.

Does not clear with steroids but with time

Treatment; hydrocortisone 1% cream

Pityriasis alba

.

LICHEN SIMPLEX CHRONICUS

Lichenified itchy skin

One of the neurodermatitis

Sustained itch-scratch circle

commonly seen in the neck

Genital

lower legs.

LICHEN SIMPLEX CHRONICUS

conscious effort to stop scratching!

- Coal tar ointment or coal tar in zinc paste

- zinc-adhesive tape he vicious cycle

Topical steroid

LICHEN SIMPLEX CHRONICUS

INFECTIVE ECZEMA

Occurs in response to an oozing skin infection.

Common in foot/ankle region

Staphylococci or streptococci.

Vaseline aggravates the condition.

Id reaction

A hyperergic reaction to the fungal infections.

Itchy eruptions of small blisters at a site distant, often the

hands and fingers

No fungi are found within these "mycids".

Clear with antifungal

MYCIDS

Erythroderma An exfoliative dermatitis affecting up to 90% of body surface area

Common causes Seborrheic dermatitis

Psoriasis

Blood dyscrasias Lichen planus

AD

Drugs Filariasis

Tinea

Mycosis fungoides