Preliminary evidence for a cognitive phenotype in Barth syndrome.

Barth syndrome (BTHS) is a rare, X-linked, recessive disorder that affects almost exclusively males. It is characterized by short stature, cardioskeletal myopathy, cyclic neutropenia, increased excretion of 3-methylglutaconic acid in the urine, and moderate hypocholesterolemia. The objective of the present study was to assess whether BTHS presents with a cognitive phenotype. Preliminary data were collected from five kindergarten or first-grade boys with BTHS. An abbreviated psychoeducational test battery was administered to each boy, and parents of each boy completed standardized behavior rating scales. Data from 120 boys of similar age or grade level were used for one comparison group; a subset of this sample comprised a comparison group that was individually matched on age and grade level to one of the five boys with BTHS. Preliminary data reflect a higher incidence of cognitive difficulties in boys with BTHS relative to both comparison groups. Boys with BTHS had significantly lower visual spatial skills, but comparable reading-related skills, when compared with either group. Although based on a small sample size, the preliminary data presented in this work are the first indication of a cognitive phenotype associated with BTHS.