1H-Magnetic Resonance Spectroscopy for The Early Diagnosis of Neuropsychiatric Systemic Lupus Erythematosus

Bae, Sung Kwon; Song, Jung Soo; Park, Won

Abstract

OBJECTIVE
To investigate the usefulness of 1H-magnetic resonance spectroscopy (1H-MRS) for the early diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE).
METHODS
Magnetic resonance image (MRI) and 1H-MRS were performed on fifteen normal volunteers (mean age, 29+/-6 years; age range, 24~40 years) and twenty seven patients with SLE: twelve (26+/-8 years; 16~42 years) with and fifteen (32+/-12 years; 13~57 years) without NPSLE. The localized 1H-MRS was performed by a GE 1.5T SIGNA MRI/MRS system (version 5.5) with active shielded gradients. For all spectra, a Stimulated Echo Acquisition Method (STEAM) localization sequence with three-pulse CHESS H2O suppression was used. The metabolite ratios of N-acetylaspartate (NAA) to creatine (Cr) and choline (Cho) to Cr measured on 1H-MRS of the basal ganglia (BG) and peritrigonal periventricular white matter (PWM).
RESULTS
The level of disease activity makers (anti-dsDNA, C3, C4, SLEDAI score), autoantibodies (lupus anticoagulant, anticardiolipin antibody, antiribosomal-P), and EEG did not showed significant difference between the patients without NPSLE and with NPSLE (p>0.05). Thirteen percent (2/15) of patients without NPSLE and fifty percent (6/12) of patient with the NPSLE showed abnormality in MRI. 1H-MRS showed significantly decreased NAA/Cr ratio in BG and increased Cho/Cr ratio in PWM for the patients with NPSLE compared to the patients without NPSLE and normal volunteers (p<0.05). No correlation was shown between the maker of disease activity and NAA/Cr in BG or Cho/Cr ratio in PWM in the SLE group (p>0.05). But negative correlation was shown between NAA/Cr in BG and Cho/Cr ratio in PWM (r=-0.58, p<0.05).
CONCLUSION
NAA/Cr ratio in BG was decreased and Cho/Cr in PWM was increased in NPSLE. The neurometabolite ratio measured by 1H-MRS may be useful in the early detection of NPSLE.