Recognition and diagnosis of neuro-ichthyotic syndromes

Abstract

The combination of neurologic disease and ichthyosis defines a heterogeneous group of rare inherited disorders that present in infancy through early adulthood. Although affected patients share the cutaneous feature of ichthyosis, there is variability in the nature and severity of neurologic disease. Impaired cognition, spasticity, sensorineural deafness, visual impairment, and/or seizures are the primary neurologic findings. Most of these disorders are caused by genetic defects in lipid metabolism, glycoprotein synthesis, or intracellular vesicle trafficking. The clinical features of some of the neuro-ichthyoses are distinct enough to allow their clinical recognition, but confirmatory biochemical or genetic tests are necessary for accurate diagnosis. Treatment of the ichthyosis is largely symptomatic, and except for Refsum's disease, there are no effective pathogenesis-based therapies for the neurologic disease.

Figure 1

Variation in the appearance of ichthyosis. (A) Newborn infant with healing collodion membrane. Note the tight, shiny skin on the hand and the areas of desquamation with underlying erythema. The skin later developed hyperkeratosis with scaling. (B) Fine scales on the back and shoulders of a 10-month-old infant with developmental delay. (C) Thick hyperkeratotic skin with a lichenified appearance on the trunk of a 2-year-old infant with Sjögren-Larsson’s syndrome. Note excoriations due to pruritus. (D) Large lamellar-like scales on the lower leg of a patient with Sjögren-Larsson’s syndrome.