X-连锁肾上腺脑白质营养不良患者氢质子核共振波谱特征及其临床意义

The characteristics and significance of 1HMRS in X-linked adrenoleukodystrophy

目的研究X-连锁肾上腺脑白质营养不良(X-ALD)患者的氢质子核共振波谱(1HMRS)特点及其在早期诊断中的作用和意义。探讨血极长链脂肪酸(VLCFA)水平、1HMRS表现与疾病的关系。观察Lorenzo油治疗后患者VLCFA水平、1HMRS的变化情况。方法7例患者均测定VLCFA水平,对其中6例在MRI定位下选定病变明显区、病变周围区及似正常区行1HMRS检测,计算N-乙酰天冬氨酸(NAA)、肌酐(Cr)、胆碱复合物(Cho)的峰面积及NAA/Cr、Cho/Cr和NAA/Cho比值。其中2例患者(1例尚未出现临床症状,1例已经发病)于Lorenzo油治疗3个月后复查VLCFA水平及1HMRS波谱。结果NAA/Cr在病变明显区比病变周围区明显降低(1.32±0.57,2.01±0.33,P<0.05),Cho/Cr在病变周围区比似正常区明显升高(2.34±0.34,1.83±0.25,P<0.05)。VLCFA水平不能反映病变的严重程度,Lorenzo油治疗3个月后患者VLCFA下降,1HMRS波谱显示未出现临床症状者中枢脱髓鞘明显减轻,已出现临床症状者波谱变化不大。结论1HMRS对X-ALD的早期诊断有重要帮助,可以先通过MRI发现中枢神经系统的脱髓鞘病变,在MRI表现正常区代谢产物已有改变,MRI和1HMRS表现可以直接反映病变的严重程度。VLCFA水平与病变的严重程度没有相关性。早期口服Lorenzo油可以延缓疾病进展,改善症状。

Objective To study the characteristics of ^1H-magnetic resonance spectrum （^1HMRS） in X-linked adrenoleukodystrophy （X-ALD） and its significance in early diagnosis and disease monitoring, The relationship between blood very long chain fatty acids （ VLCFA ） , ^1HMRS changes and the disease courses was evaluated. Methods The diagnoses of 7 cases of X-ALD were confirmed by blood VLCFA measurements, MRI findings and clinical manifestations. ^1HMRS analysis was performed in 6 of 7 patients with X-ALD, and the selected detection areas included the most obvious lesion regions, perilesional regions and normal appearing regions,with the guidance of MRI. The peak areas of metabolic products N- acetyl aspartate （ NAA ）, Choline （ Cho ）, Creatinine （Cr） and Lactic Acid （Lac ） were measured and the ratios of NAA/ Cr, Cho/Cr and NAA/Cho were calculated. ^1HMRS and blood VLCFA measurements were performed in the follow-up of 2 patients （ one with clinical symptoms before treatment and one without ） after three-month of Lorenzo oil therapy. Results The NAA/Cr decreased significantly in the most obvious regions compared to the perilesional regions （ 1.32 ±0. 57 vs 2. 01 ±0. 33, P 〈0. 05） ,and the Cho/Cr increased significantly in perilesional regions compared to the normal MRI-appearing regions（ 2. 34 ±0. 34 vs 1.83 ±0, 25, P 〈0. 05 ）. Blood VLCFA levels did not reflect the severity of the disease, Blood VLCFA levels decreased after 3 months of Lorenzo oil therapy. The ^1HMRS revealed that the CNS demyelination changes was improved in the pre-symptomatic patient, while the changes was insignificant in the other patient. Conclusion ^1HMRS can provide very helpful clues to the early diagnosis in X-ALD, and detect lesions in white matter earlier than the MRI. The metabolic products change considerably in the normal MRI-appearing regions,indicating that the ^1HMRS is a much sensitive measure. MRI and ^1HMRS changes are consistent with the lesion progress in X-ALD,while the blood VLCFA levels do not correlate to the severity. Lorenzo oil therapy can decrease the VLCFA in blood and ameliorate the CNS demyelination changes. Early diagnosis and intervention are essential for a better prognosis of X-ALD.