Neurological Manifestations of X-Linked Ichthyosis: Case Report and Review of the Literature

Abstract

A 5-year-old boy presented with mild autism and attention-deficit hyperactivity disorder (ADHD). Chromosomal microarray demonstrated a 1.7 Mb deletion at Xp22.31, which was consistent with X-linked ichthyosis (XLI). Further exam revealed dry, scaly skin on his abdomen and pretibial areas. Patients with mutations involving solely the STS gene or the recurrent ~2 Mb deletion may present with ADHD, whereas those with larger deletions including the NLGN4 gene can present with both ADHD and autism. However, our patient presented with mild autism in addition to ADHD despite having only the recurrent deletion without loss of NLGN4. Such neurological manifestations of XLI warrant attention as practical targets of clinical management.

Figure 1

(a) Facial features include the high anterior hairline, a triangular face, a short chin, widely spaced eyes, and prominent nasal bridge. The dry, scaly skin was observed in (b) the pretibial areas and (c) the abdomen.

Figure 2

(a) Affymetrix CytoScan chromosomal microarray analysis detected a 1.7 Mb deletion at Xp22.31 (6,458,939–8,135,644, genome build hg 19) in our male patient. (b) UCSC genome browser image showing the Xp22.31 deletion. The deleted interval contains six known genes (PUDP, STS, MIR4767, VCX, PNPLA4, and MIR651).