García Ribes A, Martínez González Mj, García Cazorla A
Servicio de pediatría, Hospital de Cruces, Barcaldo, 48903, Spain.
An Sist Sanit Navar. 2008;31 Suppl 2:75-89.
Inborn errors of metabolism (IEM) can have their onset in adolescence or in adulthood. Although it is difficult to contribute exact data on prevalence -because there are few studies in this respect, and IEM are regarded as infrequent- their detection is important due to the possibilities for therapy and family genetic counselling. The main symptoms of IEM in the adult are neurological, followed by hepatic. Two basic modes of onset can be established. One is acute, normally taking the form of consciousness alteration, lethargy, coma of unknown etiology in a previously healthy patient (urea cycle deficits, homocysteine remethylation disorders and porphyries are the most frequent causes). The other is an insidious, often progressive, chronic symptomathology that can involve complex clinical features, and more rarely a symptom that is isolated in a persistent way (Wilson's disease, mitochondrial diseases, lysosomal storage disorders, Refsum's disease and glycogenosis are some examples of this group). It is especially important to determine the forms of acute onset as these can present situations of extreme emergency where appropriate conduct can prevent the death of the patient. In this case, simple laboratory examinations, such as determination of ammonia, homocysteine, lactate, acylcarnitines, amino acids, organic and porfirines, can guide the diagnosis and enable the start of intensive treatment. This article provides a practical approach that deals with the general characteristics and the clinical keys for suspecting the most usual IEMs in the adult.
先天性代谢缺陷（IEM）可在青春期或成年期发病。尽管由于这方面的研究较少且IEM被认为不常见，难以提供确切的患病率数据，但因其治疗可能性和家族遗传咨询的原因，对其进行检测很重要。成人IEM的主要症状是神经方面的，其次是肝脏方面的。可以确定两种基本的发病模式。一种是急性的，通常表现为意识改变、嗜睡，在先前健康的患者中出现病因不明的昏迷（尿素循环缺陷、同型半胱氨酸再甲基化障碍和卟啉症是最常见的原因）。另一种是隐匿性的，通常是进行性的慢性症状学，可能涉及复杂的临床特征，更罕见的是持续出现孤立症状（威尔逊病、线粒体疾病、溶酶体贮积症、雷夫叙姆病和糖原贮积病是这一组的一些例子）。确定急性发病形式尤为重要，因为这些情况可能会出现极其紧急的状况，恰当的处理可以防止患者死亡。在这种情况下，简单的实验室检查，如测定氨、同型半胱氨酸、乳酸、酰基肉碱、氨基酸、有机酸和卟啉，可以指导诊断并开始强化治疗。本文提供了一种实用方法，涉及成人中最常见IEM的一般特征和疑似诊断的临床要点。
