Jellum E, Dollekamp H, Brunsvig A, Gislefoss R
Institute of Clinical Biochemistry, Rikshospitalet, Oslo, Norway.
J Chromatogr B Biomed Sci Appl. 1997 Feb 7;689(1):155-64. doi: 10.1016/s0378-4347(96)00333-7.
Capillary electrophoresis (CE) equipped with a diode-array detector, and GC-MS have been used to determine diagnostic metabolites occurring in urine of patients with various metabolic disorders. The urine samples were injected directly onto the CE instrument without any pretreatment. GC-MS required extraction and derivatisation before separation. Identification of abnormal metabolites was based on migration times and characteristic diode-array spectra, or mass spectral library search when GC-MS was used. The CE method has previously been shown capable of diagnosing several metabolic diseases, and was now used on more difficult cases. CE readily diagnosed glyceric aciduria and the secondary metabolite in lysinuric protein intolerance, orotic acid. Methylmalonic aciduria required pressure elution in addition to high voltage to accomplish diagnosis. In mevalonic aciduria the characteristic metabolite had weak light absorption and the mevalonate peak also co-eluted with endogenous aromatic acids making diagnosis difficult. Both in the latter case and with the disorders glutaric aciduria I and glyceroluria, GC-MS was the method of choice. A possible role of CE in the routine system for diagnosing metabolic disorders, might be to use this method for pre-testing all urine samples. Samples with abnormal CE-profiles would subsequently be given high priority for more elaborate analysis with GC-MS and amino acid analyzer. In a different project a CE instrument designed for serum protein analysis was used to study sera from patients with myelomatosis. The method also allowed identification of the various immunoglobulins using immunosubtraction. Samples collected after diagnosis as well as many years prior to disease were available through the Janus-bank. This large serum bank comprises samples collected since 1973 at intervals from nearly 300000 blood donors. It was found that the monoclonal immunoglobulins characteristic of the disease started to appear in serum up to 15 years before clinical diagnosis.
配备二极管阵列检测器的毛细管电泳（CE）和气相色谱 - 质谱联用仪（GC - MS）已被用于测定患有各种代谢紊乱患者尿液中出现的诊断性代谢物。尿液样本未经任何预处理直接注入CE仪器。GC - MS在分离前需要进行萃取和衍生化。异常代谢物的鉴定基于迁移时间和特征性二极管阵列光谱，使用GC - MS时则基于质谱图库检索。CE方法此前已被证明能够诊断多种代谢疾病，现在被用于更疑难的病例。CE很容易诊断出甘油酸尿症以及赖氨酸尿性蛋白不耐受症中的次生代谢物乳清酸。甲基丙二酸尿症除了高压外还需要压力洗脱才能完成诊断。在甲羟戊酸尿症中，特征性代谢物光吸收较弱，且甲羟戊酸峰还与内源性芳香酸共洗脱，这使得诊断困难。在后一种情况以及戊二酸尿症I型和甘油尿症中，GC - MS是首选方法。CE在代谢紊乱诊断常规系统中的一个可能作用，可能是用这种方法对所有尿液样本进行预检测。CE图谱异常的样本随后将被优先进行更详细的GC - MS和氨基酸分析仪分析。在另一个项目中，一台设计用于血清蛋白分析的CE仪器被用于研究骨髓瘤患者的血清。该方法还允许使用免疫扣除法鉴定各种免疫球蛋白。通过雅努斯银行可以获得诊断后以及疾病发生前多年采集的样本。这个大型血清库包含自1973年以来从近300000名献血者那里定期采集的样本。发现该疾病特有的单克隆免疫球蛋白在临床诊断前长达15年就开始出现在血清中。
