Korean J Radiol.  2001 Dec;2(4):239-242. 10.3348/kjr.2001.2.4.239.

Localized Proton MR Spectroscopic Detection of Nonketotic Hyperglycinemia in an Infant

• Choi CG
• Lee HK
• Yoon JH

• KMID: 754095
• DOI: http://doi.org/10.3348/kjr.2001.2.4.239

Abstract

Nonketotic hyperglycinemia (NKH) is a rare metabolic brain disease caused by deficient activity of the glycine cleveage system. Localized proton MR spectroscopy (echo-time 166 msec), performed in an infant with the typical clinical and biochemical features of neonatal NKH, showed a markedly increased peak intensity at 3.55 ppm, which was assigned to glycine. Serial proton MR spectrosocpic studies indicated that glycine/choline and glycine/total creatine ratios correlated closely with the patient's clinical course. Proton MR spectroscopy was useful for the non-invasive detection and monitoring of cerebral glycine levels in this infant with NKH.

Keyword

Brain, MR spectroscopy; Brain, metabolism

MeSH Terms

Case Report
Human
Hyperglycinemia, Nonketotic/*diagnosis
Infant, Newborn
Magnetic Resonance Imaging
*Magnetic Resonance Spectroscopy
Male
Protons

Figure

• 

  Fig. 1 A control spectrum of stimulated-echo acquisition mode (STEAM) sequence (TR/TE, 3000/166) obtained at the parietal white matter of a one-month-old infant with neonatal seizure, for comparison. NAA, N-acetylaspartate; tCr, total creatine; Cho, choline-containing compounds

• 

  Fig. 2 Proton MR imaging and spectra obtained from an infant with nonketotic hyperglycinemia. All spectra are scaled individually and cannot be directly compared. A. Axial T1-weighted (600/16) image obtained with a spin-echo sequence and 18-cm field of view, 256 × 192 matrix, and 5-mm contiguous sections, with the voxel location as indicated for proton MR spectroscopy. B. A spectrum obtained from the parietal white matter shows a prominent singlet at 3.55 ppm (arrow), which is assigned to glycine. The peak intensity of glycine is much higher than that of Cho (glycine/Cho, 1.58) and of tCr (glycine/tCr, 2.42). C. A follow-up spectrum obtained after treatment and symptomatic improvement shows a slightly decreased peak glycine intensity. The observed peak intensity is similar to that of Cho (glycine/Cho, 1.05) and slightly higher than that of tCr (glycine/tCr, 1.31). D. A final spectrum, obtained after symptoms worsened, shows a markedly increased peak glycine intensity. The observed peak intensity is again much higher than that of Cho (glycine/Cho, 1.80) and of tCr (glycine/tCr, 1.60), and peak lactate intensity has increased to 1.33 ppm.

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