Tan It-Koon, Gajra Bani, Lim Maria S F
Clinical Biochemistry Laboratories, Department of Pathology, Singapore General Hospital, Singapore.
Ann Acad Med Singap. 2006 Nov;35(11):804-13.
Recommended by the National Advisory Council of the Disabled, the Ministry of Health of Singapore supported a nationwide study of inherited metabolic disorders (IMDs). When the 5-year project ended, investigations were provided as a diagnostic service. This paper documents our 13-year experience.
Patients with symptoms suggestive of an IMD were referred. Investigations on heparinised blood and/or urine included amino acid analysis using a Beckman 6300 Amino Acid Analyser, organic acids analysis using a Hewlett- Packard gas chromatography and mass spectrometry, mucopolysaccharides quantitative assay and high-resolution electrophoresis, sugars by thin-layer chromatography.
Of the 3656 patients studied from 1992 to 2005, IMDs were found in 127 (77 males; 50 females; age range, 1 day to 56 years). Their ethnic distribution was: 55.1% Chinese, 19.7% Malays, 11.0% Indians, 11.0% other races and 3.2% unknown. IMD diagnosed comprised 41 (32.3%) organic acidurias, 34 (26.8%) amino acidaemias/acidurias, 14 (11.0%) urea cycle defects, 15 (11.8%) mucopolysaccharidoses, 6 (4.7%) carbohydrate disorders and 17 (13.4%) others. Twenty-three (18.1%) cases were diagnosed during the neonatal period and 36 (28.3%) after the age of 13.
Positive detection rate was 3.5% and 48 IMDs were found. Significant proportion of cases had late-onset IMDs. Early identification of IMDs permits timely management, genetic counselling and prenatal diagnosis.
在新加坡国家残疾人咨询委员会的推荐下，新加坡卫生部支持了一项关于遗传性代谢疾病（IMD）的全国性研究。当这个为期5年的项目结束时，调查被作为一种诊断服务提供。本文记录了我们13年的经验。
转诊有IMD症状提示的患者。对肝素化血液和/或尿液的检测包括使用贝克曼6300氨基酸分析仪进行氨基酸分析、使用惠普气相色谱和质谱进行有机酸分析、粘多糖定量测定和高分辨率电泳、通过薄层色谱分析糖类。
在1992年至2005年研究的3656例患者中，发现127例患有IMD（77例男性；50例女性；年龄范围为1天至56岁）。他们的种族分布为：55.1%为华人，19.7%为马来人，11.0%为印度人，11.0%为其他种族，3.2%种族不明。诊断出的IMD包括41例（32.3%）有机酸尿症、34例（26.8%）氨基酸血症/氨基酸尿症、14例（11.0%）尿素循环缺陷、15例（11.8%）粘多糖贮积症、6例（4.7%）碳水化合物紊乱和17例（13.4%）其他疾病。23例（18.1%）病例在新生儿期被诊断，36例（28.3%）在13岁以后被诊断。
阳性检出率为3.5%，共发现48种IMD。相当比例的病例患有迟发性IMD。IMD的早期识别有助于及时管理、遗传咨询和产前诊断。
