Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Congenital myasthenic syndromes with prominent limb girdle involvement are an important differential diagnosis for congenital myopathies because of the therapeutic considerations. We present a case where accurate diagnosis was delayed for many years. Fluctuations of weakness were misinterpreted as effects of alternative treatments. Weakness was generalised, most prominently in the arms. Fatigability was more prominent in less affected muscles revealed by a positive Simpson test. Stimulation single fibre electromyography confirmed the suspected neuromuscular transmission defect. The marked response to pyridostigmine and cognitive impairment pointed to a myasthenic syndrome due to impaired glycosylation. Two mutations in trans were found in DPAGT1, the gene coding for dolichyl-phosphate N-acetylglucosaminephosphotransferase, one novel, the other previously reported in a rare form of congenital disorder of glycosylation. Gene expression studies revealed that both mutations reduce DPAGT1 expression. Phenotypic features not previously described for DPAGT1 CMS included restricted ocular abduction and long finger flexor contractures.

Original publication

DOI

10.1016/j.nmd.2014.11.013

Type

Journal article

Journal

Neuromuscul Disord

Publication Date

03/2015

Volume

25

Pages

253 - 256

Keywords

Congenital myasthenia, DPAGT1, Differential diagnosis to congenital myopathy, Adolescent, Arm, Diagnosis, Differential, HEK293 Cells, Humans, Leg, Magnetic Resonance Imaging, Male, Muscle, Skeletal, Mutation, Myasthenic Syndromes, Congenital, Myotonia Congenita, N-Acetylglucosaminyltransferases