Lamellar Ichthyosis/non-Bullous Ichthyosiform Erythroderma - Diagnostic Tests

Diagnostic Tests

Histology

Histology is rather non-specific and often simply shows compact orthohyperkeratosis. However, it may be useful for differential diagnosis (decreased stratum granulosum in ichthyosis vulgaris).

Ultrastructural analysis

This examination is very important, because there are some specific features of certain LI/NCIE subtypes. For instance, transglutaminase deficiency is associated with cholesterol clefts in the stratum corneum.

Snap frozen skin biopsies for transglutaminase activity test of the skin

The histochemical transglutaminase assay measures functional activity of transglutaminases in the epidermis and has been proven to be a sensitive screening test for lamellar ichthyosis type 1.

Transglutaminase Assay

Diagnostic Tools

This section offers to professional users instruments helpful to establish the disease diagnosis. Specific entries include:

1. model questionnaires, protocols, or checklists, which may guide clinicians and laboratory personnel in the diagnostic procedure of specific disease groups/subgroups;
2. a list of cell biology/biochemical tools used for laboratory diagnosis of specific diseases or group of diseases;
3. a list of molecular genetics tools, including mutational screening procedures, oligonucleotide primer sequences, PCR amplification conditions, and other details for selected diseases. In this section, you also find the link for the gene-specific page of the Weizmann Institute of Science GeneCards website (http://www.genecards.org) which is an integrated database including information on disease relationships, SNPs, gene expression, gene function and more.
4. a mutation database with a GENESKIN updated list of the mutations identified in the genes responsible for selected diseases. A link with the gene-specific page at the Human Gene Mutation Database maintained at the University of Wales in Cardiff (www.hgmd.org) and other databases, such as the collagen database in Leicester (www.le.ac.uk/genetics/collagen), is also available.

Model Questionnaire

Here you will find the downloadable version of the non-bullous congenital ichtyosiform erythroderma patient form. This document is currently used to collect patient details before sending the biological sample to the diagnostic laboratory, in order to ease cellular and/or molecular investigations.

Ichthyosis patient form

Molecular Genetic Tools

ALOX12B
ALOXE3
ALOXE3	CYP4F22
Ichthyin
TGM1

ABCA12

Mutation Database

ABCA12
ALOX12B
ALOXE3
YP4F22	No link available yet
Ichthyin	No link available yet
TGM1