Diagnostik von Myopathien

Deschauer, M.; Müller-Reible, C. R.; Rösler, K. M.; Schoser, B.; Wanschitz, J.; Weis, J. und Zierz, S. (2016): Diagnostik von Myopathien. In: Aktuelle Neurologie, Bd. 43, Nr. 10: S. 599-607

Abstract

Background: Diagnosis of myopathies can be difficult due to clinical and genetical heterogeneity. This guideline should enable a diagnostic workup in patients with myopathies to facilitate therapy in treatable disorders. A correct classification of hereditary forms is important for genetic counselling, estimation of the prognosis, and therapy. It is important to decipher indications for a muscle biopsy and to perform it in an appropriate way to reach maximal diagnostic yield. Methods: Members of the guideline committee were neurological experts for myopathies from Austria, Swiss and Germany but also a neuropathologist, a human geneticist, and a member of the German neuromuscular patient support group. For the update of the guideline, that was issued for the last time in 2012, the recent literature published until early 2016 was considered. The update was performed according to S1-level. Results: According to the clinical examination a syndrome diagnosis should be established. Laboratory testing should include creatine kinase (CK) supplemented by laboratory investigation for testing inflammatory and endocrine abnormalities. In all patients with suspected myopathy needle electromyography has to be performed to distinguish between neurogenic and myopathic weakness and to identify myotonia. For imaging of muscle magnetic resonance tomography is the most suitable method particularly to find the correct localization for the biopsy. Generally, a biopsy is indicated for the detection of inflammatory myopathies, although detection of specific antibodies can help to distinguish between different myositis forms. For the diagnosis of hereditary myopathies a biopsy is indicated if the phenotype is not specific and primary molecular genetic testing is difficult. The sample size of the biopsy must be sufficient and the specimen must be properly handled to enable histological examinations including immunohistology, and Western blotting. Furthermore, additional specimen for enzyme measurements, electron microscopy and DNA extraction are needed. Analyses of the muscle biopsy should be performed in a specialized laboratory. In several hereditary myopathies diagnosis can be confirmed by molecular testing with dispensation of a biopsy, e.g. dystrophinopathies, myotonic dystrophy type 1 and 2, oculopharyngeal muscular dystrophy, facio-scapulo-humeral muscular dystrophy type 1 and 2. Next generation sequencing enables an efficient investigation of numerous genes in one assay (panel diagnosis) or even all parts of the genome (exome/genome). These novel methods should be used in selected patients examined in centers for neuromuscular disorders that show a defined phenotype that can be caused by mutations in different genes, e.g. limb girdle muscular dystrophy. Since 1.7.2016 the German insurance companies pay for, "small" panels (maximum 25 kilo bases), cost coverage of more elaborate testing has to be applied for individually.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0302-4350
• Sprache: Deutsch