To showcase a case with multiple diagnoses contributing to a seemingly coherent clinical presentation consistent with myopathy.

Myopathies such as inclusion body myositis generally do not show NCS changes, and in this case the patient was found to likely have AMSAN in addition to inclusion body myositis on muscle biopsy and cervical spine cord compression on imaging.

An 81 year old gentleman with a past medical history of type 2 Diabetes, hyperlipidemia, hypertension, and prior stroke, presented with 3 months of numbness/tingling of bilateral hands and feet, and 2 weeks of rapidly progressive muscle weakness. Examination was significant for weakness in all extremities with upper extremities worse than lower, and proximal muscles more affected than distal, as well as decreased reflexes throughout. Nerve conduction study had evidence of moderate sensorimotor polyneuropathy with primarily axonal features, concerning for Acute Sensory and Motor Axonal Neuropathy leading to treatment with IVIG with some initial clinical improvement and then plateau on day 2. Given that EMG was also showing possible signs of myopathy with reduced amplitude, he underwent muscle and nerve biopsy for further diagnostic clarity. As patient did not fully improve with IVIG,  Plasmapheresis was done, during which he began to retain urine leading to MRI of the cervical spine which showed severe degenerative changes with lack of CSF signal, and cord compression, for which he underwent cervical laminectomies with some improvement. Muscle biopsy then resulted with Inclusion body myositis, statin was withheld, and patient had continued improvement.

Our patient had AMSAN, cervical cord compression, and inclusion body myositis.

It is important to remain vigilant with full workup for all differential diagnosis especially in settings where clinical response does not meet the expected progression, as is highlighted by this case with multiple contributing conditions.