Download MBBS Dermatology PPT 11 Ichthyosis Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Dermatology PPT 11 Ichthyosis Lecture Notes


ICHTHYOSIFORM DISORDERS

ICHTHYOSES &

ERYTHROKERATODERMAS

? Disorders of cornification
? Abnormal differentiation and desquamation of the epidermis result in a

defective epidermal barrier.

? Clinically all `Ichthyoses' have generalized scaling of the skin
? Erythrokeratodermas: circumscribed areas of erythema and hyperkeratosis

without obvious scaling.
ICHTHYOSES

? Disorder of keratinization that manifests as dry and scaly skin resembling

`fish skin'

? Ichthys=fish

? Two broad types
1. Defects in keratin or intercellular substances(lipids, fillagrin) , limited to skin
2. Metabolic disease with involvement of other organs

TYPES OF ICHTHYOSES

Congenital ichthyoses

? Ichthyosis vulgaris
? X linked ichthyosis
? Lamel ar ichthyosis
? Epidermolytic ichthyosis
? Non Bul ous Ichthyosis erythroderma
? Epidermolytic ichthyosis (bul ous CIE)
? Superficial epidermolytic ichthyosis (ichthyosis bul osa of

Siemens)

? Ichthyosis hystrix Curth?Macklin


ICHTHYOSIS VULGARIS

? Autosomal dominant with high penetrance
? Molecular defect: Fil agrin deficiency in epidermis
? Resulting in retension hyperkeratosis
? Age of onset : 1-4 yrs
? Prevalence : 1 in 300
? Improvement in summer
? Lesions persists life long

ICHTHYOSIS VULGARIS

? Scaling : generalized
? Dirty brown polygonal scales: legs
? Fine, adherent scales on trunk, extremities
? Face, flexures spared
? Asymptomatic
? Asso. Features-

? increased palmer lines, furrowed heels
? Keratosis pilaris
? Atopic dermatitis




? Treatment

? Emolients , glycerine
? 10 % Urea cremes
? Kerolytic cremes with lactic and

salicylic acid

? Systemic acitretin rarely used

X LINKED RECESSIVE ICHTHYOSIS

Prominent dark-brown scales - lower legs.

? X linked recessive

Smal er dark-brown scales -trunk, with sparing of skin folds

? Males (females carrier)
? Defect : Steroid sulfatase deficiency
? Age in onset: infancy
? Fine to large, dark, adherent scales
? Extremities, trunk, neck and lateral face
? Preauricular area involvement: pathognomic
? Involves flexures
? Neck:almost invariably involved, "dirty neck".
? Palms, soles spared


X LINKED RECESSIVE ICHTHYOSIS

Dark scales on the neck, "dirty neck".

? Asso. Features
? Cryptorchidism
? Corneal opacity
? Failure of spontaneous labour in carrier

females

? Topical

? Humectants- Propylene glycol
? Keratolytics ? salicylic acid
? Retinoids

? Systemic Retinoids ? rarely necessary

LAMELLAR ICHTHYOSIS

? Autosomal recessive
? Transglutaminase-1 deficiency
? This enzyme is expressed in upper layers of the epidermis,
? facilitates formation of the cornified cel envelope by cross-linking numerous

structural proteins to the lipid envelope.

? Age of onset: Birth as col oidion baby
? Persists throughout life


LAMELLAR ICHTHYOSIS

? Over the first weeks , the col odion membrane is replaced by generalized scales.
? Scales are large, brown, plate-like:mosaic or bark-like pattern
? scales are central y attached with raised borders, often leading to superficial fissures.
? minimal to no associated erythroderma
? Asso.

? Heat intolerance : Intraepidermal constriction of sweat ducts
? Scarring alopecia,
? Eclabium
? Severe ectropion - madarosis, conjunctivitis, incomplete lid closure with ensuing keratitis.
? Palmoplanter keratoderma


LAMELLAR ICHTHYOSIS

? Neonatal care as in col odion babies.
? Oral retinoids: Acitretin from early childhood.
? Topical

? Vitamin D3 derivatives,
? Tazarotene
? Lactic acid and
? Propylene glycol

HARLEQUIN ICHTHYOSIS

? Autosomal recessive
? Rare
? Age of onset: Birth
? Very thick, yel ow?brown plates of scale that tightly encase the

neonate: ARMOR like

? severe immobilization and restricts ventilation
? Extreme ectropion,
? Eclabium
? Ear deformities
? Microcephaly
HARLEQUIN ICHTHYOSIS

? Shortly after birth, the hyperkeratotic cast cracks
? Large, yel ow, adherent plates
? Broad, deep, intensely red fissures
? Increased transcutaneous loss of water, electrolyte imbalances

temperature instability.

? Skin infections or sepsis
? Hands and feet are edematous , covered by a mitten-like casing
? Autoamputation

HARLEQUIN ICHTHYOSIS

? Premature delivery
? Neonatal death common : sepsis or respiratory insufficiency
? Survivors develop severe CIE-like phenotype

? Early administration of acitretin (1 mg/kg/day)


CONGENITAL ICHTHYOSIFORM ERYTHRODERMA (CIE)

? Autosomal recessive

? Asso. Features

? Age of onset : Birth

? Heat intolerance;

? Frequently col odion membrane at birth;

? variable scarring

? Generalized fine, white scale with a

? alopecia,

"powdery" consistency

? Ectropion

? erythroderma

? Treatment

? palms and soles - diffuse, fissuring

keratoderma

? increased intake of fluids, calories, iron and

protein

Congenital ichthyosiform erythroderma.

Intense redness and fine, flaky, white scale on the trunk and arms.

Close-up of fine white coarser yel owish scale in a background of prominent

erythema.
BULLOUS CONGENITAL ICHTHYOSIFORM

ERYTHRODERMA

? Autosomal dominant
? Heterozygous mutations in the genes encoding keratin 1 (KRT1) and keratin 10

(KRT10)

? These keratins expressed in spinous and granular layers
? Age of onset : birth
? Erythroderma, peeling, erosions and widespread denuded areas
? Skin fragility, blistering and erythema decrease over time
? Hyperkeratosis develops later during infancy and prevails
? Sepsis, fluid and electrolyte imbalance in the neonatal period : life threatening

BULLOUS CONGENITAL ICHTHYOSIFORM

ERYTHRODERMA

? Episodes of blistering and

? Management in NICU as col oidion baby

secondary skin infections

problematic later in life

? Later ? hyperkeratosis

? Accompanied by a pungent body

? Keratolytic creams

odor,

? emol ients and humectants

? Associated posture and gait

? antibacterial soaps, chlorhexidine or

abnormalities.

dilute sodium hypochlorite baths to

? Tremendous impact on patients'

control bacterial colonization

quality of life

? Low doses systemic Retinoids


ERYTHROKERATODERMA VARIABILIS

? Autosomal dominant
? Coexistence of transient erythematous patches and stable hyperkeratotic plaques
? One of these features frequently predominates
? Age of onset : at birth or within first year
? Erythema - variable intensity, persist for min to hours
? Sharply demarcated, yel ow? brown thickened hyperkeratotic plaques with

geographic borders on limbs, buttocks, trunk

? Symmetric distribution
? Topicals for mild diseases

? Keratolytics (e.G. Lactic acid, urea, -hydroxy acids)
? Retinoids (e.G. Tretinoin, tazarotene)

? Systemic retinoids ? acitretin, isotretinoin for more extensive disease


COLLODION BABY

? At birth, neonate is covered with a taut, shiny, transparent membrane, resembling a

plastic wrap

? Membrane formed by thickened stratum
? Tautness of the membrane leads to

? ectropion,
? eclabium
? hypoplasia of nasal,auricular cartilage.

? At risk for

? thermoinstability,
? hypernatremic dehydration,
? skin infections and sepsis.
? Pneumonia due to restricted ventilation and aspiration of amniotic fluid containing scales.
? Sucking impaired- malnutrition


COLLODION BABY

? After birth, membrane dries, cracks and breaks
? Fissures ?

? impair epidermal barrier function,
? percutaneous loss of water - fluid and electrolyte imbalances,
? entry of microorganisms; skin infections, sepsis

? Circular bands of hardened skin - vascular constriction, distal

edema.

? In two weeks, membrane peels off in sheets
? Transition to the underlying disease phenotype takes place

Col odion baby.

Day 1: eclabium.

Day 8 : erythema,
diffuse mild scaling,
misshapen ears.
COLLODION BABY

Col oidon baby seen in
? Lamel ar ichthyosis
? Congenital ichthyosiform erythroderma
? Self-healing/self-improving col odion baby

Treatment ? NICU- humidified incubator
? protective isolation to prevent infection
? prevent or treat dehydration, electrolyte imbalance
? protective padding and lubricants
? wet compresses,light emol ients on skin
? Prevent dehydration , dyselectrolytemia, hypothermia, infection

A NEONATE/YOUNG INFANT WITH A

COLLODION MEMBRANE/ICHTHYOSIS

? Complete blood count, electrolytes, hepatic panel, immunoglobulin levels (including IgE)
? Peripheral blood smear
? Light microscopic examination of clipped hairs (including eyebrow hairs)
? Hearing screen
? Ophthalmologic examination
? Consider skin biopsy,
? Consider X-rays to evaluate epiphyses, especial y if ichthyosiform lesions are in a

mosaic distribution pattern

This post was last modified on 07 April 2022