3 hydroxyisobutyric aciduria is characterised by ketoacidotic episodes, cerebral anomalies and facial dysmorphism. It is an organic aciduria that involves valine metabolism. Thirteen cases have been described in the literature so far. Transmission is thought to be autosomal recessive.

Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border.