GABA Transaminase Deficiency With Survival Into Adulthood

Abstract

γ-Aminobutyric acid (GABA)-transaminase deficiency is an ultra-rare disorder of GABA metabolism that was described for decades as an early-onset epileptic encephalopathy plus movement disorder and hypersomnolence with mortality in early childhood. We report 2 affected siblings in adolescence and adulthood, both with profound developmental impairment, intractable epilepsy, movement disorder, and behavioral fluctuations. This considerably expands the phenotype and longevity of this inherited neurotransmitter disease.

Keywords: ABAT gene; GABA metabolism; GABA-T deficiency; GABA-transaminase deficiency; India.

Figure 1.

MRI at 4 years of age. Axial T2 weighted images A and B show increased T2 signal in the subinsular region and subcortical white matter of the temporal pole (arrows). Axial T2 weighted image C shows abnormal increased T2 signal in the centrum semiovale (arrows). Coronal T2 weighted image D shows decreased undulations of the hippocampal heads (arrows) and prominent temporal horns of the lateral ventricles.

Figure 2.

MRI at 13 years of age. Axial T2 weighted images A and B show increased T2 signal in the subinsular region and subcortical white matter of the temporal pole (arrows). Axial T2 weighted image C shows abnormal increased T2 signal in the centrum semiovale (arrows). Coronal T2 weighted image D shows decreased undulations of the hippocampal heads (arrows) and prominent temporal horns of the lateral ventricles.