2-Hydroxyglutaric aciduria

2-hydroxyglutaric aciduria is a rare, autosomal recessive neurometabolic disorder characterized by the significant elevation of urinary levels of hydroxyglutaric acid.

Forms
2-hydroxyglutaric aciduria is an organic aciduria, and has two distinct isometric variants:

L-2-hydroxyglutaric aciduria
The L-2 form is more common, severe, and mainly affects the central nervous system. The basal ganglia are affected, and cystic cavitations in the white matter of the brain are common, beginning in infancy. This form is chronic, with early symptoms such as hypotonia, tremors, and epilepsy declining into spongiform leukoencephalopathy, muscular choreodystonia, mental retardation, and psychomotor regression.

It is associated with L2HGDH.

D-2-hydroxyglutaric aciduria
The D2 form is rare, with symptoms including macrocephaly, cardiomyopathy, mental retardation, hypotonia, and cortical blindness.