Ultrastructural study of the skin in Sj�gren ? Larsson syndrome

Abstract

The ichthyosiform skin and the uninvolved skin of a 5-year-old Japanese female with Sjögren-Larsson syndrome were examined by light and electron microscopy to elucidate the keratinization disorder. Light microscopically, the epidermis of the ichthyosiform skin showed acanthosis, papillomatosis and hyperkeratosis. The horny cells had a basket-weave appearance. The granular cell layer was slightly thickened. Slight round cell infiltration and vascular dilatation were seen in the upper dermis. The uninvolved skin was histologically normal. Electron microscopically, in both ichthyosiform and uninvolved skin, abnormal lamellar or membranous inclusions were present in the cytoplasm of horny cells of the epidermis. These inclusions appeared to be derived from some of the lamellar bodies and/or abnormal membranous structures found in the cytoplasm of spinous and granular cells. Mitochondria in the epidermal basal cells were more numerous in the ichthyosiform skin than in the uninvolved skin. These findings indicate that, whether the skin is involved or not, the epidermis of the patient with this disorder may always have a structural abnormality, which may be genetically determined. Local environmental factors may play a role in inducing the acanthosis and papillomatosis of the epidermis.

Novel and recurrent ALDH3A2 mutations in Italian patients with Sjögren–Larsson syndrome

“…1b). Such abnormal lamellar inclusions in the granular and horny layer cells are a typical finding in SL syndrome and may be derived from keratinosomes, as already suggested by various authors (Bernardini et al 2007;Ito et al 1991;Rizzo 1993). …”

Abnormal fatty alcohol metabolism in cultured keratinocytes from patients with Sjögren-Larsson syndrome

“…Alterations in the lipid composition of these membranes by experimental manipulation or originating from inborn errors of lipid metabolism can disrupt the epidermal water barrier and lead to ichthyosis (39). Ultrastructural studies of the skin in SLS reveal misshapen lamellar bodies, some lacking membranes, abnormal cytoplasmic lamellar inclusions in the granular keratinocytes, and lipid droplets in the SC, indicative of defective in vivo lipid metabolism (41,42).…”

Novel ALDH3A2 Heterozygous Mutations Are Associated with Defective Lamellar Granule Formation in a Japanese Family of Sjögren–Larsson Syndrome

“…Previously, abnormal lamellar or membranous inclusions in the cornified cells were observed in the lesional skin of a SLS patient, although causative genetic abnormalities were not known in that particular case (Ito et al, 1991). The inclusions were speculated to be lamellar granule-in-origin.…”