Clinical And Molecular Findings In Hyperornithinemia-Hyperammonemia-Homocitrullinuria Syndrome

The authors report the clinical and molecular findings in eight patients with hyperornithinemia, hyperammonemia, and homocitrullin-uria (HHH) syndrome. The most consistent neurologic finding was spastic paraparesis, seen in five of the eight patients. However, all showed signs of pyramidal tract involvement. A broad spectrum of pathogenetic mutations (including missense, nonsense, splice site, insertion, and deletions) were identified in the ORNT1 gene.