Motor Neuron Disease – additional opinion
Short summary
71-year-old female developed progressive dysarthria and dysphagia. She underwent multiple investigations and started Rilutek. Her EMG study does not meet published criteria for the electrophysiologic diagnosis of motor neuron disease. In the expert's opinion, a definite diagnosis is not possible at the present time, and there would be utility in repeating clinical and electrophysiologic testing. The expert also recommends to perform pulmonary function testing.
Medical Background
Diagnosis: motor neuron disease.
The patient is a 71 year old lady who developed progressive speaking difficulties since June of 2008. More recently, she developed progressive swallowing difficulties as well.
In December of 2008 was seen by Dr. X, neurology specialist in Milan. He describes her speech difficulty as “Spastic dysarthria with slow and nasal speech”. He notices decreased mobility in the tongue and palate with no other neurological signs on exam.
Multiple investigations including blood work, brain MRI and electro diagnostic studies were performed, the results are summarized below.
Rilutek 50 mg twice a day was started on January 22nd 2009.
Previous investigations:
- Blood work: Complete blood count, chemistry, glucose, CK levels, liver function tests, thyroid function tests, serum protein electrophoresis (SPEP) were all within normal limits. SPEP with immunofixation was performed, but the report is unclear.
- Brain MRI (1/2008) revealed evidence of cortical cerebral atrophy with possible periventricular white matter changes. There were no other intracranial lesions. The actual MRI images were not available for review.
- EMG (French) in January 2009: Nerve conduction studies revealed bilateral median neuropathy across the wrists, worse on the left. Ulnar sensory and motor responses were within normal limits on both sides. Tibial nerve motor responses were within normal limits on both sides. F-wave responses of right and left ulnar and tibial nerves were within normal limits. Repetitive nerve stimulation of the left spinal accessory and right facial nerves were within normal limits. Single fiber EMG was normal. Needle EMG study revealed abnormal spontaneous activity in the left orbicularis oris, right FDI and right biceps. It also revealed evidence of chronic denervation in the right and left tibialis anterior. Left FDI and Glossus muscles were normal.
- Transcranial magnetic stimulation (French) in January 2009: within normal limits.
Past medical and family history is not available.
Social and occupational history is not available.
Current list of medication is not available.
Medical opinion
With regard to the EMG testing that was done while the study might be compatible with motor neuron disease, the study does not meet published criteria for the electrophysiologic diagnosis of motor neuron disease. This is not uncommon in patients with clinical symptoms limited to the bulbar region and mostly spastic i.e. upper motor neuron deficits. Pulmonary function testing should include spirometry and maximal inspiratory and maximal expiratory pressures. The latter are particularly helpful for evaluation of respiratory muscle weakness.
Assuming that all the blood work that was recommended was normal including no monoclonal gammopathy, I do not believe that there is much utility in traveling to Israel at the present time. I have checked and there is currently no active study of motor neuron disease which is recruiting participants. While a definite diagnosis is not possible at the present time there would be utility in repeating clinical and electrophysiologic testing in 3-6 months to determine if a more definite diagnosis is possible. As noted previously not infrequently early in the course of ALS it is not possible to come to a definite diagnosis. As noted below, there is no biologic marker for ALS, so testing is focused on trying to rule out other disorders and show diffuse lower motor neuron involvement. As noted above the EMG which I reviewed did not show diffuse lower motor neuron involvement, so an electrophysiologic diagnosis is also not possible at the current time. Follow-up testing may allow a more definitive diagnosis.
