Unique Ichthyosis/MR Syndrome with Seizures, Severe Developmental Delay, Failure to Thrive, Mild Dysmorphology and Eye Findings

Abstract

We describe three children born to non-consanguinous Puerto Rican parents with severe delay, ichthyosis, minor anomalies, seizures (2/3), reactive air-way disease (2/3) severe failure to thrive and unique eye findings. The oldest child, with almost no skills, is the most affected, but hypoxemia in the neonatal period may have affected his outcome. The two younger siblings have developmental delay that was almost as severe; they could not sit or stand unsupported, crawl or talk. But they are more interactive than their older sibling. All children have mild mongoloid eye slant, epicanthic folds, deep orbits, esotropia, nystagmus, low set ears, long philtrum, small chin and severe failure to thrive. Ichthyosis was confirmed by typical pathological findings. All children have unique eye findings, consisting of decreased visual acuity, esotropia, and horizonal, pendular nystagmus. The pupils dilated paradoxically to light. An electroretinogram in the oldest boy showed an unusual cone response, with a minimal a-wave and prolonged b-wave. An MRI showed an arachnoid cyst and partial ACC. Chromosome, phytanic acid, fatty alcohol dehydrogenase, and long chain fatty acid oxidation testing were negative. Hair analysis was normal, suggesting the children did not have trichothiodystrophy. To determine whether the children had a contiguous gene syndrome consisting of loss of the steroid sulfatase gene and adjacent genetic material, the steroid sulfatase(STS) gene was expanded by PCR utilizing primers at both ends of the gene, and the products isolated and sequenced. This testing was normal. These children appear to have a unique genetic/metabolic disorder which can be distinguished from other Ichthyosis/MR syndromes such as Sjogren-Larson, Tay, Refsum's, Rud's and the Netherton syndromes.