Congenital myasthenic syndrome due to mutation in CHRNE gene with clinical worsening and thymic hyperplasia attributed to association with autoimmune-myasthenia gravis.
We report a patient with congenital myasthenic syndrome (CMS) due to mutation in CHRNE with symptoms since the age of 4; mild to moderate fatigable weakness involved mainly ocular, bulbar and limb muscles; functional impact of the disease in their development and physical activity was modest. By the age of 34, the patient experienced gradual worsening of fatigue with dyspnoea and pronounced limb weakness, requiring significant increase of pyridostigmine. Further, a remarkable and sustained clinical improvement followed thymectomy with hyperplastic thymus. Despite of the absence of detectable antibodies to acetyl-choline receptor (AChR) (including clustered-AChR), muscle-specific kinase and low-density lipoprotein receptor-related protein-4 antibodies in the serum obtained nine years after thymectomy, the clinical, genetic and histological features are in keeping with the extremely rare association of two rare neuromuscular junction disorders - CMS and myasthenia gravis (MG). The inexistence of other conditions that could potentially associate with thymic hyperplasia also supports the diagnosis of MG.
['Santos|Ernestina|E|', 'Moreira|Isabel|I|', 'Coutinho|Ester|E|', 'Gonçalves|Guilherme|G|', 'Lopes|Carlos|C|', 'Lopes Lima|José|J|', 'Leite|M Isabel|MI|']
D000328:Adult D018450:Disease Progression D006801:Humans D008297:Male D018482:Muscle, Skeletal D009154:Mutation D009157:Myasthenia Gravis D020294:Myasthenic Syndromes, Congenital D011978:Receptors, Nicotinic D013934:Thymectomy D013952:Thymus Hyperplasia
Congenital myasthenic syndrome Neuromuscular junction disorder Myasthenia gravis