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11 Cards in this Set
- Front
- Back
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Sjogren-Larsson Syndrome
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Inheritance
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Autosomal recessive; Fatty aldehyde dehydrogenase (FALDH) gene 1 7p] 1.2
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Prenaatal
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CVS/amniocentesis: fatty aldehyde clehydrogenase or fatty alcohol oxicloreductase
assay; DNA mutation analysis if gene defect is known Fetal skin biopsy at 23 weeks |
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Incidence
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More than 200 cases reported, many from northern Sweden
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Age at Presentation
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Infancy (ichthyosis); by age 2 3 y (CNS
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Pathogenesis
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Over 50 mutations in the FALDH gene have been identified leading to a decrease in fatty alcohol: NAD oxidoreductase (FAO) activity and subsequent defective conversion of fatty alcohol to fatty acid; this pathway is important in epidermal lipid synthesis as well as catabolism of phospholipids and sphingolipids in CNS myelin; accumulation of fatty alcohol, fatty aldehyde modified lipids and leukotriene B4, which contributes to pruritus
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Clinical
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Skin
Infancy Generalized ichthyosis with erythroderma, areas of fine scaling, areas of large lamellar scaling, hyperkeratosis, pruritus After Infancy Generalized darker scale without erythema accentuated in flexures, lower abdomen and back/sides of neck; spares central face Central Nervous System Mental retardation, spastic di tetraplegia with scissor gait, speech deficits, epilepsy Eyes Atypical retinal pigment degeneration in macula glistening white dots in a peri¬ macular distribution; (many but not all cases) retinal pigmentary changes in some patients |
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D/Dx
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Lamellar ichthyosis (p. 10)
Congenital ichthyosiform erythroderma (p. 12) NLSD Multiple sulfatase deficiency |
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Lab
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Enzyme assay in cultured fibroblasts; DNA mutation analysis if defect known
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Management
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Referral to dermatologist emolliation, retinoids
Referral to neurologist, ophthalmologist, orthopedist Zileuton inhibits leukotriene B4 synthesis and may help pruritus |
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Prognosis
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Dependent on severity of CNS complications if wheelchair bound and severely retarded, prognosis is guarded; otherwise patients typically live well into adulthood
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