Lamellar Ichthyosis Workup

Updated: Apr 01, 2022
  • Author: Chris G Adigun, MD, FAAD; Chief Editor: Dirk M Elston, MD  more...
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Approach Considerations

Genetic diagnosis and counseling of this disorder is imperative, and prenatal diagnosis for those at risk is encouraged. Genetic linkage studies have confirmed that mutations in TGM1, the gene encoding transglutaminase-1, is responsible for the development of this disorder. [22] Prenatal diagnosis is achieved through examination of the fetal skin by biopsy or amniotic fluid by electron microscopy. The expression and increased activity level of transglutaminase 1 is a key diagnostic tool. [7]


Histologic Findings

Skin biopsy results show a normal or thickened granular layer, mild-to-moderate hyperkeratosis with increased mitoses, and a perivascular lymphocytic infiltrate. In autosomal dominant lamellar ichthyosis, the stratum granulosum and stratum corneum are separated by a prominent transforming zone and scales contain elevated triglyceride and fatty acid levels, which aids in differentiation from autosomal recessive lamellar ichthyosis.