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More than 750 inborn errors of metabolism have been described so far.
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Many inborn errors of metabolism present in extremis and can be easily diagnosed based on plasma/urine metabolic tests performed in laboratories specialized in biochemical genetics.
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Some inborn errors of metabolism are treatable and require early and urgent intervention to prevent permanent sequelae.
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Most treatable inborn errors of metabolism can be identified by newborn screening.
Inborn Errors of Metabolism Overview: Pathophysiology, Manifestations, Evaluation, and Management
Section snippets
Key points
Pathophysiologic classification of inborn errors of metabolism
The vast majority of IEM involve abnormalities in enzymes and transport proteins and can be divided into the following 2 large clinical categories.
Category 1 includes disorders that either involve only one functional system (such as the endocrine system, immune system, or coagulation factors) or affect only 1 organ or anatomic system (such as the intestine, renal tubules, erythrocytes, or connective tissue). Presenting symptoms are uniform (eg, a bleeding tendency in coagulation factor defects
Clinical presentations of inborn errors of metabolism
A few metabolic disorders are recognized through newborn screening of the general population (as for phenylketonuria) or of at-risk families. Apart from these few, metabolic disorders present in 6 major groups of clinical circumstances.
When and how far to investigate a metabolic disorder
All organs being dependent on cellular metabolism, it could be anticipated that IEM can potentially disturb all organs and cellular systems in any scenario at any age and with any mode of heredity. But of course this does not mean that extensive metabolic investigations are required in all individuals with unexplained symptomatology.
Despite the massive progress accomplished in medical and scientific research that has to do with the brain, mainly in neurophysiology, brain imaging, classical and
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No commercial or financial conflicts of interest are declared. À. Garcia-Cazorla is supported by the "Plan Nacional de I+D+I and Instituto de Salud Carlos III- Subdireccion General de Evaluacion y Fomento de la Investigacion Sanitaria", project PI15/01082, and the European Regional Development Fund (FEDER [PI15/01082]).