Thai A C, Ng W Y, Loke K Y, Lee W R, Lui K F, Cheah J S
Department of Medicine, National University of Singapore, Republic of Singapore.
Diabetologia. 1997 Dec;40(12):1425-30. doi: 10.1007/s001250050845.
An autoimmune basis for the pathogenesis of insulin-dependent diabetes mellitus (IDDM) is supported by the frequent presence of autoantibodies - islet cell antibodies (ICAs) and GAD antibodies (GADab). However, in Chinese patients with clinical IDDM, a low prevalence of ICAs was observed. In non-insulin-dependent diabetic (NIDDM) patients, it has been suggested that the presence of GADab may identify a subset of latent autoimmune diabetes in adults (LADA). We determined the frequency of GADab in a large group of 134 IDDM and 168 NIDDM Chinese patients, and assessed the relation with ICAs status. Results showed that 39.6% IDDM and 16.1% NIDDM patients had GADab, and 20.1% and 4.8%, respectively had detectable ICAs. Frequency of GADab positivity was not influenced by whether the patients had youth or adult-onset IDDM or NIDDM, or by duration of diabetes. NIDDM patients seropositive for GADab shared similar clinical characteristics and fasting C-peptide levels with those who were GADab negative. Presence of GADab therefore did not serve to identify a subgroup of patients with latent or slow-onset IDDM. Half (53%) of our IDDM patients had neither GADab nor ICAs. The reason for this observation is unclear. One theory is that other autoantigens yet to be identified may be contributory. Alternatively, in the Chinese, autoimmunity may not be the major factor in the pathogenesis of IDDM.
胰岛素依赖型糖尿病（IDDM）发病机制的自身免疫基础得到自身抗体——胰岛细胞抗体（ICAs）和谷氨酸脱羧酶抗体（GADab）频繁出现的支持。然而，在中国临床诊断为IDDM的患者中，观察到ICAs的患病率较低。在非胰岛素依赖型糖尿病（NIDDM）患者中，有人提出GADab的存在可能识别出一部分成人隐匿性自身免疫性糖尿病（LADA）。我们测定了134例IDDM和168例NIDDM中国患者这一大组人群中GADab的频率，并评估了其与ICAs状态的关系。结果显示，39.6%的IDDM患者和16.1%的NIDDM患者有GADab，分别有20.1%和4.8%的患者可检测到ICAs。GADab阳性频率不受患者是青年或成人发病的IDDM或NIDDM，以及糖尿病病程的影响。GADab血清学阳性的NIDDM患者与GADab阴性患者具有相似的临床特征和空腹C肽水平。因此，GADab的存在并不能识别出隐匿性或缓慢发病的IDDM患者亚组。我们一半（53%）的IDDM患者既没有GADab也没有ICAs。这一观察结果的原因尚不清楚。一种理论是，可能还有其他尚未确定的自身抗原起作用。或者，在中国人群中，自身免疫可能不是IDDM发病机制的主要因素。
