Neurology:谷氨酰胺转移酶抗体或可特异诊断谷蛋白共济失调

 

基于先前对谷蛋白共济失调患者谷氨酰胺转移酶(TG)6的免疫反应研究，来自英国Sheffield的Marios Hadjivassiliou等医师研究了谷氨酰胺转移酶6抗体对谷蛋白共济失调的诊断作用，发表在2013年5月7日的Neurology杂志上，结果显示：谷氨酰胺转移酶6抗体为谷蛋白依赖性的，或能成为谷蛋白共济失调敏感性及特异性高的标记物。

该研究为前瞻性队列研究，招募来自英国谢菲尔德Royal Hallamshire医院及芬兰Tampere大学乳糜泻临床中心的有共济失调，谷蛋白性或神经性，乳糜泻(CD)和运动障碍的患者。这些患者分为特发性散发共济失调组、乳糜泻组、神经对照组及健康对照组。所有患者都进行了TG6抗体检测。血清阳性的患者进行十二指肠活检。除此之外，有15例特发性共济失调而血清谷蛋白相关疾病抗体阴性患者进行了十二指肠活检及TG免疫球蛋白A的检测。

在65例特发性散发共济失调患者中有21例(32%)TG6抗体阳性，48例谷蛋白共济失调患者中35例(73%)阳性，50例乳糜泻患者中16例(32%)阳性，82例神经对照组中4例(5%)阳性，

57例健康对照组中2例(4%)阳性。谷蛋白共济失调组患者中42%有肠病，51%有共济失调及TG6抗体。连续监测的15例特发性散发共济失调患者中5例有TG2免疫球蛋白A沉积，其中4例TG6抗体检测阳性。在无谷蛋白饮食1年后，TG6抗体的低度明显降低到无法检测的程度。

研究结果显示，谷氨酰胺转移酶6抗体为谷蛋白依赖性的，或能成为谷蛋白共济失调敏感性及特异性高的标记物。

Transglutaminase 6 antibodies in the diagnosis of gluten ataxia.
OBJECTIVES
The previous finding of an immunologic response primarily directed against transglutaminase (TG)6 in patients with gluten ataxia (GA) led us to investigate the role of TG6 antibodies in diagnosing GA.
METHODS
This was a prospective cohort study. We recruited patients from the ataxia, gluten/neurology, celiac disease (CD), and movement disorder clinics based at Royal Hallamshire Hospital (Sheffield, UK) and the CD clinic, Tampere University Hospital (Tampere, Finland). The groups included patients with idiopathic sporadic ataxia, GA, and CD, and neurology and healthy controls. All were tested for TG6 antibodies. Duodenal biopsies were performed in patients with positive serology. In addition, biopsies from 15 consecutive patients with idiopathic sporadic ataxia and negative serology for gluten-related disorders were analyzed for immunoglobulin A deposits against TG.
RESULTS
The prevalence of TG6 antibodies was 21 of 65 (32%) in idiopathic sporadic ataxia, 35 of 48 (73%) in GA, 16 of 50 (32%) in CD, 4 of 82 (5%) in neurology controls, and 2 of 57 (4%) in healthy controls. Forty-two percent of patients with GA had enteropathy as did 51% of patients with ataxia and TG6 antibodies. Five of 15 consecutive patients with idiopathic sporadic ataxia had immunoglobulin A deposits against TG2, 4 of which subsequently tested positive for TG6 antibodies. After 1 year of gluten-free diet, TG6 antibody titers were significantly reduced or undetectable.
CONCLUSIONS
Antibodies against TG6 are gluten-dependent and appear to be a sensitive and specific marker of GA.