DISEASE CARD

Disease group Disorders of cornification
DISEASE NAME Ichthyosis
Estimated prevalence 1:200

 

Ichthyoses are determined as Mendelian disorders of cornification (MeDOC) that are characterized by generalized scaling of the skin. From a pathophysiological perspective, they are associated with abnormal differentiation and/or abnormal desquamation (retention hyperkeratosis versus hyperproliferative hyperkeratosis/epidermal hyperplasia)

In a consensus conference in 2009, a new classification system and terminology has been established for ichthyoses.1 In two main categories, non-syndromic forms (phenotype restricted to the skin) are distinguished from syndromic forms (involvement of other organs). The onset of the disease is in almost all ichthyoses (except Refsum disease) at birth or in early childhood.

 

Classification

Inherited ichthyosis – nonsyndromic forms

Mode of inheritance

Gene(s)

Common ichthyoses

Ichthyosis vulgaris (IV)[146700]

A(s)D

FLG

Recessive X-linked ichthyosis (XRI) – non syndromic presentation [308100]

XR

STS

Autosomal recessive congenital ichthyosis (ARCI)

Major types

Harlequin ichthyosis (HI) [242500]

AR

ABCA12

Lamellar ichthyosis (LI), Congenital ichthyosiform erythroderma (CIE)  [242300] [242100] [601277]

[606545] [604777] [612281] [613943] [615023] [615024] [602400] [617320] [617571] [617574]

AR

TGM1, NIPAL4,

ALOX12B,

ALOXE3, ABCA12, CYP4F22, LIPN, CERS3, PNPLA1, ST14, CASP14, SULT2B1, SDR9C7

Minor variants

Self-improving congenital ichthyosis

[242300] [242100] [606545]

AR

TGM1, ALOX12B, ALOXE3

Bathing suit ichthyosis (BSI) [242300]

AR

TGM1

Keratinopathic ichthyosis (KPI)

Major types

Epidermolytic ichthyosis (EI) [113800]

AD

KRT1, KRT10

Superficial epidermolytic ichthyosis (SEI) [146800]

AD

KRT2

Minor variants

Annular epidermolytic ichthyosis (AEI) [607602]

AD

KRT1, KRT10

Ichthyosis Curth-Macklin (ICM) [146590]

AD

KRT1, KRT10

AR Epidermolytic ichthyosis (AREI)  [113800]

AR

KRT10

Congenital reticular ichthyosiform erythroderma (CRIE), Ichthyosis with confetti (IWC) [609165]

AD

KRT10, KRT1

Epidermolytic naevi [113800]

Somatic mutations

KRT1, KRT10

Other forms

 

Loricin keratoderma (LK) [604117]

AD

LOR

Erythrokeratodermia variabilis (EKV) [133200]

AD

GJB3, GJB4

Peeling skin disease (PSD) [270300]

AR

CDSN

Keratosis linearis – ichthyosis congenital – keratoderma (KLICK) [601952]

AR

POMP

Exfoliative ichthyosis [607936]

AR

CSTA

A(s)D = autosomal semidominant; AD = autosomal dominant; XR = x-linked recessive; AR = autosomal recessive; OMIM in [ ] http://www.omim.org

 

Inherited ichthyosis – syndromic forms

Mode of inheritance

Gene(s)

X-linked ichthyosis syndromes

RXLI – syndromic presentation [308100]

XLR

STS (and others)

Ichthyosis follicularis-atrichia-photophobia (IFAP) syndrome [308205]

XLR

MBTPS2

Conradi-Hünermann-Happle syndrome (CDPX2) [302960]

XLD

EBP

Autosomal ichthyosis syndromes (with…)

Prominent hair abnormalities

Netherton syndrome (NS) [256500]

AR

SPINK5

Ichthyosis-hypotrichosis syndrome (IHS) [602400]

AR

ST14

Ichthyosis-hypotrichosis-sclerosing cholangitis syndrome (IHSC) [607626]

AR

CLDN1

Trichothiodystrophy (TTD) [601675] [616390] [616395]

AR

ERCC2/XPD, ERCC3/XPB, GTF2H5/TTDA

Prominent neurologic signs

Sjögren-Larsson syndrome (SLS) [270200]

AR

ALDH3A2

Refsum syndrome (RS) [266500]

AR

PHYH, PEX7

Mental retardation-enteropathy-deafness-neuropathy-ichthyosis-keratodermia syndrome (MEDNIK) [609313]

AR

AP1S1

Ichthyotic keratoderma, spasticity, hypomyelination, and dysmorphic features (IKSHD) [618527]

AD

ELOVL1

Ichthyosis, spastic quadriplegia, mental retardation (ISQMR) [614457]

AR

ELOVL4

Fatal disease course

Gaucher syndrome type 2 (GS) [230900]

AR

GBA

Multiple sulfatase deficiency (MSD) [272200]

AR

SUMF1

Cerebral dysgenesis-neuropathy-ichthyosis-palmoplantar keratoderma syndrome (CEDNIK) [609528]

AR

SNAP29

Arthrogryposis-renal dysfunction-cholestasis syndrome (ARC) [208085]

AR

VPS33B

Other associated signs

Keratitis-Ichthyosis-Deafness syndrome (KID) [148210]

AD

GJB2, GJB4

Keratitis-Ichthyosis-Deafness autosomal recessive (KIDAR) [242150]

AR

AP1B1

Neutral lipid storage disease with ichthyosis / Chanarin-Dorfman syndrome (CDS) [275630]

AR

ABHD5, CGI-58

Severe dermatitisā€multiple allergiesā€metabolic wasting syndrome (SAM) [615508]

AR/AD

DSG1, DSP

Ichthyosis prematurity syndrome (IPS) [608649]

AR

SLC27A4

A(s)D = autosomal semidominant; AD = autosomal dominant; XR = x-linked recessive; AR = autosomal recessive; OMIM in [ ] http://www.omim.org

 

 

 

References

Oji V, Tadini G, Akiyama M, Blanchet Bardon C, Bodemer C, Bourrat E, et al. Revised nomenclature and classification of inherited ichthyoses: results of the First Ichthyosis Consensus Conference in Sorèze 2009. J Am Acad Dermatol. 2010;63(4):607-641.