Nazaimoon W M, Azmi K N, Rasat R, Ismail I S, Singaraveloo M, Mohamad W B, Letchuman R, Sheriff I H, Faridah I, Khalid B A
Division of Endocrinology, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur.
Med J Malaysia. 2000 Sep;55(3):318-23.
This study determined the prevalence and significance of autoantibodies to GAD65 (GAD Ab), insulin (IAA), tyrosine-like phosphatase (IA2) and islet-cell (ICA) in a group of 213 young Malaysian Type 1 diabetics, diagnosed before the age of 40 years. Venous blood was taken at fasting, and at 6 minutes post-glucagon (1 mg i.v.). IAA was detected in 47.4%, GAD Ab in 33.8%, IA2 in 8.9% and ICA in 1.4% of the subjects. When based on post-glucagon C-peptide level of 600 pmol/L, 172 (80.7%) patients had inadequate pancreatic reserve, while the remainder 41(19.3%) showed normal response. The autoantibodies, either alone or in combination, were detectable in both groups of patients; higher prevalence in those with poor or no beta-cell function (73.3% versus 46.3%, p = 0.0001). Although the prevalence of GAD Ab was highest in newly diagnosed patients (< 5 years), unlike IA2 and ICA, the marker remained detectable in 24-25% of those patients with long-standing disease. Nineteen patients could probably belong to the "latent autoimmune diabetes in adults (LADA)" subset, where pancreatic reserve was adequate but patients had detectable autoantibodies and insulin-requiring. On the other hand, 68 of the 213 patients (32%) were seronegative, but presented with near or total beta-cell destruction. Thus, as has also been suggested by others, there is indeed etiological differences between the Asian and the Caucasian Type 1 diabetics, and, there is also the possibility that other, but unknown autoantigens are involved in causing the pancreatic damage.
本研究确定了213名40岁之前确诊的马来西亚年轻1型糖尿病患者中，抗谷氨酸脱羧酶65（GAD Ab）、胰岛素（IAA）、酪氨酸样磷酸酶（IA2）和胰岛细胞（ICA）自身抗体的患病率及其意义。空腹及静脉注射1 mg胰高血糖素后6分钟采集静脉血。受试者中，47.4%检测到IAA，33.8%检测到GAD Ab，8.9%检测到IA2，1.4%检测到ICA。以胰高血糖素刺激后C肽水平600 pmol/L为标准，172例（80.7%）患者胰腺储备不足，其余41例（19.3%）反应正常。两组患者均可检测到单独或联合存在的自身抗体；β细胞功能差或无β细胞功能的患者中患病率更高（73.3%对46.3%，p = 0.0001）。虽然新诊断患者（<5年）中GAD Ab患病率最高，但与IA2和ICA不同，在病程较长的患者中仍有24% - 25%可检测到该标志物。19例患者可能属于“成人隐匿性自身免疫性糖尿病（LADA）”亚组，其胰腺储备充足，但患者可检测到自身抗体且需要胰岛素治疗。另一方面，213例患者中有68例（32%）血清学阴性，但存在近完全或完全β细胞破坏。因此，正如其他人所指出的，亚洲和白种人1型糖尿病患者之间确实存在病因差异，并且也有可能存在其他未知的自身抗原参与胰腺损伤的发生。
