“How can doctors tell the difference between ALS and MMN?”
My husband has recently been diagnosed with ALS. This was determined from an MRI (which showed everything was ok there) and nerve conduction studies. His condition is mostly on his right side and began with his right hand but now affects his right arm and right foot. He does not experience difficulties with breathing or any sensory deprivation such as numbness or tingling. The doctor was very quick to diagnose ALS and I understand that misdiagnosis is common with MMN. We would like further tests but don't know what to ask for to eliminate the possibility of MMN. Can you help? Many thanks in advance!
Male | 60 years old
Complaint duration: 6 months
Medications: none
Conditions: otherwise healthy
2 Answers
While both conditions early on may mimic each other, the main differentiating feature is the fact that patients with ALS have upper and lower motor neuron signs in the exam (including from the brain stem to the lumbosacral spine) Neurological exam and EMG/Nerve Conduction studies help differentiate one from the other. You can always have genetic testing for ALS. The four genes tested are. (SOD1, C9orf72, TARDBP, and FUS. Ask your Neurologist how he/she was able to determine one from the other and concluded it was ALS. Do not be afraid to ask. If your Neurologist is experienced in diagnosing and differentiating ALS from MMN, it should not be a problem to explain to you.
Dr. F
Dr. F
As far as I know, this is a common clinical conundrum. To my knowledge, the diagnosis of either of these rest largely on clinical finding and electrophysiology studies. That being said, there are imaging findings, for example:
https://radiopaedia.org/articles/amyotrophic-lateral-sclerosis-3?lang=us
I'd say find a neurologist at a large tertiary center with experience /training in movement disorders. I wish I could be more help.
I will pray for y'all. All the best....
https://radiopaedia.org/articles/amyotrophic-lateral-sclerosis-3?lang=us
I'd say find a neurologist at a large tertiary center with experience /training in movement disorders. I wish I could be more help.
I will pray for y'all. All the best....
