Clinical, biochemical and ultrastructural study on the pathogenesis of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome.
A 10-year-old boy with the hyperornithinemia, hyperammonemia and homocitrullinuria (HHH) syndrome is described. With dietary restriction of protein intake and supplementary administration of L-ornithine and L-arginine, the high concentration of ammonia decreased and the clinical signs of truncal ataxia and lethargy improved. A deficiency of ornithine transport into liver mitochondria was demonstrated biochemically, and glycogen granules and smooth surface endoplasmic reticulum were increased, but mitochondria showed normal construction ultrastructurally. Cranial computed tomography (CT) showed diffuse white matter low density and cerebellar vermis atrophy. The impairment of ornithine transport and energy production in the central nervous system may be related to the cranial CT findings and neurological signs.
Nakajima
M
M
Division of Child Neurology, Institute of Neurological Sciences, Tottori University School of Medicine, Japan.
Ishii
S
S
Mito
T
T
Takeshita
K
K
Takashima
S
S
Takakura
H
H
Inoue
I
I
Saheki
T
T
Akiyoshi
H
H
Ichihara
K
K
D000592:Amino Acid Metabolism, Inborn Errors / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D000641:Ammonia / Q000097:blood*; D001120:Arginine / Q000008:administration & dosage; D001921:Brain / Q000000981:diagnostic imaging; D002648:Child; D002956:Citrulline / Q000031:analogs & derivatives* / Q000652:urine; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D006801:Humans; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism / Q000648:ultrastructure; D009952:Ornithine / Q000008:administration & dosage / Q000097:blood* / Q000378:metabolism; D014057:Tomography, X-Ray Computed
D008112:Liver Glycogen; C001352:homocitrulline; D002956:Citrulline; D000641:Ammonia; D001120:Arginine; D009952:Ornithine