Dystrophic Myopathy of the Diaphragm with Recurrent Severe Respiratory Failure is Congenital Myasthenic Syndrome 11.

We here present the case of a patient with a congenital myasthenic syndrome (CMS) due to pathogenic variants in the RAPSN gene. During childhood he experienced recurrent episodes of respiratory failure during respiratory infections. This and other cases were reported as isolated dystrophy of the diaphragmatic musculature. In adulthood, whole exome sequencing revealed two heterozygous pathogenic variants in the RAPSN gene. This led to the revision of the diagnosis to rapsyn CMS11 (OMIM:616326, MONDO:0014588). EMG, muscle ultrasound and the revision of muscle biopsies taken in childhood support this diagnosis. After the revision of the diagnosis, treatment with pyridostigmine was started. This resulted in a reduction of fatigability and an improvement in functional abilities and quality of life.

Having an eye for myotonic dystrophy: A qualitative study on experiences and support needs in myotonic dystrophy type 1 patients with a diagnostic delay after early-onset cataract.

Myotonic dystrophy type 1 is a neuromuscular disorder affecting multiple organ systems and is characterized by a variety of clinical presentations. Anticipation leads to an earlier and more severe phenotype in subsequent generations. Early-onset cataract is a common initial manifestation of the late or adult-onset type of myotonic dystrophy 1. Due to its multicausal nature, early-onset cataract is often not recognized as a feature of this disease, leading to diagnostic delay resulting in consequences for successive generations, treatment and counseling. A qualitative study with semi-structured interviews was performed with purposive sampling of eight participants with myotonic dystrophy type 1 and early-onset cataract to investigate the physical and psychosocial consequences experienced due to diagnostic delay. Prior to the early-onset cataract, all participants experienced other multisystem symptoms that could have been explained by myotonic dystrophy. The diagnostic delay had severe hereditary consequences: a subsequent generation with more severely affected (grand)children was born resulting in large emotional burden for the patients. To conclude, early-onset cataract is a warning sign and ophthalmologists play a crucial role in the early detection of myotonic dystrophy type 1 by recognizing this symptom and preventing the birth of severely affected children leading to emotional and psychosocial consequences.