Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029089 (ophthalmoplegia)
 3,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders caused by perturbations in signal transduction at the neuromuscular junction. Defects in muscle, skeletal, receptor tyrosine kinase (MuSK) cause two distinct phenotypes: fetal akinesia with multiple congenital anomalies (Fetal akinesia deformation sequence [MIM:208150]) and early onset congenital myasthenia (myasthenic syndrome, congenital, 9, associated with acetylcholine receptor deficiency [MIM:616325]). Myasthenia due to MuSK deficiency has variable clinical features, ranging from a milder presentation of isolated late-onset proximal muscle weakness; to a severe presentation of prenatal-onset diffuse weakness, ophthalmoplegia, respiratory failure, and vocal cord paralysis (VCP). Here, we propose to expand the phenotypic spectrum for MuSK deficiency to include isolated VCP with the absence of other classical myasthenic symptoms. We evaluated two brothers who presented in the neonatal period with respiratory failure secondary to isolated VCP. Research-based exome sequencing revealed biallelic likely pathogenic variants in MUSK (MIM:601296). Both children had normal gross motor and fine motor development. One brother had speech delay, likely due to a combination of tracheostomy status and ankyloglossia. This case report suggests that CMS should be on the differential diagnosis for familial recurrence of VCP.
 ...
PMID:Isolated vocal cord paralysis in two siblings with compound heterozygous variants in MUSK: Expanding the phenotypic spectrum. 3071 42

Congenital myasthenic syndromes are clinically and genetically heterogeneous disorders characterized by a neuromuscular transmission defect. Mutations in novel genes have been described in recent years. Among these, MUSK gene mutations are extremely rare, with only 8 families identified worldwide to date. We report a Spanish case, a carrier of one known hetero-allelic missense mutation and one newly identified MUSK gene variant. Our patient presented with congenital onset ophthalmoplegia and palpebral ptosis associated with limb-girdle weakness and exercise intolerance without prominent fatigability, developed during his twenties. He was misdiagnosed as mitochondrial myopathy because of paraclinic and histologic findings, but detailed clinical examination prompted us to reassess him with repetitive stimulation technique, demonstrating decremental response and suggesting myasthenic syndrome. A genetic study confirmed the clinical diagnosis allowing us to started treatment with excellent clinical response.
 ...
PMID:Congenital Ophthalmoplegia and Late-Onset Limb Weakness Caused by MUSK Mutations. 3245 97