遗传性果糖不耐受症

遗传性果糖不耐受症（HFI）是一种罕见的、由于先天性醛缩酶B缺陷导致的果糖代谢病。为常染色体隐性遗传性疾病。特征是摄取果糖、蔗糖或山梨醇后发生严重的低血糖。若不及时终止此类食物，会导致肝肾功能损伤及生长发育障碍。本病诊断比较困难，治疗主要以对症治疗和饮食控制为主。本文就遗传性果糖不耐受症的临床生化特征、诊治方法及醛缩酶B损伤的分子学基础进行综述，为临床早期发现、早期诊断、早期治疗遗传性果糖不耐受症提供参考。     

Diagnostische Bedeutung von Muskelbiopsien bei metabolischen Myopathien

Summary In the diagnosis of metabolic myopathies the use of biochemical methods, in addition to morphological examination of muscle biopsies, is often necessary in order to identify a specific metabolic defect. In order to narrow down the spectrum of biochemical methods, extensive clinical investigation and morphological examination, including histology, enzyme histochemistry and electromicroscopy if necessary have to be done beforehand. Patients are classified in the following groups: 1) progressive muscular weakness and/or muscle wasting with storage of a) glycogen, b) lipid or c) mitochondrial alterations; 2) recurrent rhabdomyolysis induced by fasting or exercise a) with glycogen storage or b) without any specific morphological alterations. The spectrum of metabolic defects comprises disorders of glycogen and glucose metabolism (deficiency of acid maltase, debranching and branching enzyme, phosphorylase, phosphofructokinase and other glycolytic enzymes), lipid metabolism (carnitine deficiency, carnitine palmitoyl transferase deficiency), mitochondria (respiratory chain disorders, pyruvate dehydrogenase deficiency) and others such as adenylate deaminase deficiency. In some of these e.g. infantile acid maltase deficiency and mitochondriopathies, it is clinically more important when organs other than muscle are affected; however, muscle biopsy is a useful substrate for diagnosis of these metabolic disorders.

Mit Unterstützung durch die DFG und die Friedrich Baur Stiftung, München     

小梁切开术治疗先天性青光眼的临床观察

目的：观察小梁切开术治疗先天性青光眼的疗效。     

Diagnosing,discarding, or de-VUSsing: A practical guide to (un)targeted metabolomics as variant-transcending functional tests

PurposeFor patients with inherited metabolic disorders (IMDs), any diagnostic delay should be avoided because early initiation of personalized treatment could prevent irreversible health damage. To improve diagnostic interpretation of genetic data, gene function tests can be valuable assets. For IMDs, variant-transcending functional tests are readily available through (un)targeted metabolomics assays. To support the application of metabolomics for this purpose, we developed a gene-based guide to select functional tests to either confirm or exclude an IMD diagnosis.MethodsUsing information from a diagnostic IMD exome panel, Kyoto Encyclopedia of Genes and Genomes, and Inborn Errors of Metabolism Knowledgebase, we compiled a guide for metabolomics-based gene function tests. From our practical experience with this guide, we retrospectively selected illustrative cases for whom combined metabolomic/genomic testing improved diagnostic success and evaluated the effect hereof on clinical management.ResultsThe guide contains 2047 metabolism-associated genes for which a validated or putative variant-transcending gene function test is available. We present 16 patients for whom metabolomic testing either confirmed or ruled out the presence of a second pathogenic variant, validated or ruled out pathogenicity of variants of uncertain significance, or identified a diagnosis initially missed by genetic analysis.ConclusionMetabolomics-based gene function tests provide additional value in the diagnostic trajectory of patients with suspected IMD by enhancing and accelerating diagnostic success.     

Plasma ionized magnesium in tubular disorders with and without total hypomagnesemia

 Selective electrodes have been designed for determining plasma ionized magnesium. In kidney disease the relationship between ionized and total circulating magnesium is often altered. Hence plasma ionized magnesium (ETH 7025 membrane) was determined in 25 patients with primary renal tubular disorders; 6 patients had total hypomagnesemia. Total plasma magnesium was never reduced in the remaining 19 patients. Plasma ionized magnesium values were low in the 6 patients with total hypomagnesemia. In 18 of the 19 patients without total hypomagnesemia plasma ionized magnesium values were not reduced. Ionized hypomagnesemia was noted in a patient with normal total plasma magnesium in the context of hypercalciuric nephrocalcinosis of unknown origin. The study demonstrates an excellent concordance between plasma total and ionized magnesium in tubular disorders associated with total hypomagnesemia and a good concordance in tubular disorders that are not linked with total hypomagnesemia. The determination of circulating ionized magnesium is of little value in the diagnostic work-up of the vast majority of renal tubular disorders. The determination might perhaps disclose latent hypomagnesemia in nephrocalcinosis of unknown cause. Received: 20 March 1998 / Revised: 28 May 1998 / Accepted: 29 May 1998     

A new case of malonyl coenzyme A decarboxylase deficiency presenting with cardiomyopathy

A new case of mitochondrial malonyl coenzyme A decarboxylase deficiency is described. The patient presented with an initial episode of metabolic acidosis, seizures, hypoglycemia, and cardiac failure at 2 months of age which slowly resolved. Subsequent evaluations at 4 years of age for developmental delay revealed a prominent elevation of malonic acid in urine. Malonyl carnitine was also elevated. The activity of malonyl CoA decarboxylase in cultured fibroblasts was 7% of normal. Conclusion Malonyl CoA decarboxylase deficiency may result in inhibition of fatty acid oxidation, which may account for the cardiomyopathy. Received: 12 April 1996 / Accepted: 24 September 1996     

Inborn errors of immunity with eosinophilia

Monogenic diseases of the immune system, also known as inborn errors of immunity (IEIs), are caused by single-gene mutations and result in immune deficiency and dysregulation. More than 400 monogenic diseases have been described to date, and this number is rapidly expanding. The increasing availability of next-generation sequencing is now facilitating the diagnosis of IEIs. It is known that IEIs can predispose a person to not only infectious diseases but also cancer and immune disorders, such as inflammatory, autoimmune, and atopic diseases. IEIs with eosinophilia and atopic diseases can occur in several disorders. IEIs with eosinophilia have provided insights into human immunity and the pathogenesis of allergic diseases. Eosinophilia is not a rare finding in clinical practice, and it often poses problems in terms of etiologic research and differential diagnoses. Secondary eosinophilia is the most common form. The main underlying conditions are infectious diseases such as parasitic infections, allergic disorders, drug reactions, and of course IEIs. In clinical settings, the recognition of IEIs in the context of an allergic phenotype with eosinophilia is critical for prompt diagnosis and appropriate treatment aimed at modulating pathophysiological mechanisms and improving clinical symptoms.