In this report, we describe a girl who presented with clinical features mimicking Charcot Marie Tooth disease, but was found to have BAG3 myopathy with no cardiac and late onset respiratory involvement. 

13 year old girl presented with history of toe walking, clumsiness, and falls since the age of 3 years. Her development was normal, however, was noted to toe walk and have frequent falls starting at the age of 3 years.  Family history was unremarkable. Examination revealed bilaterally tight heel cords, decreased muscle bulk in both lower legs, and symmetric distal leg weakness with absent deep tendon reflexes in her lower extremities. Length dependent deficits involving all sensory modalities of lower extremities were noted. Gait was on toes and wide based. Mild thoracolumbar scoliosis and high arched feet were noted without a rigid spine or proximal weakness. Remainder of her examination was unremarkable. Serum creatinine kinase level was elevated. MRI of the spine was normal. NCS at the time of presentation showed findings suggestive of demyelinating sensorimotor polyneuropathy; electromyography was not performed.  Trio whole exome sequencing (WES) confirmed the presence of a de novo heterozygous pathogenic variant, c.626C>T (p.Pro209Leu), in BAG3 gene. Left quadriceps muscle biopsy confirmed myopathy with changes consistent with MFM.

To our knowledge, this is the first report of a BAG3 myopathy presenting similarly to a demyelinating CMT with no evidence of rigid spine, cardiac,  or respiratory involvement. This case adds to the repertoire of expanding phenotypic spectrum of BAG3 myopathy. This report highlights the importance of thorough electrophysiological examination and muscle biopsy for establishing a precise diagnosis and emphasizes the utility of WES for etiological delineation.