Diseases that simulate Amyotrophic lateral sclerosis: clinical differences (P4.465)

Objective: To describe frequency and clinical characteristics of Amyotrophic lateral sclerosis mimic sydromes (ALSms) patients referred as Amyotrophic lateral sclerosis (ALS) but who were re-diagnosed as ALSms Background: ALS is the most common motoneuron disease (MND). Several diseases can mimic ALS, known as ALSms, leading to misdiagnosis. Design/Methods: We retrospectively analyzed the medical records of patients who presented symptoms of MND at the onset of the disease from 2002 to 2017. Patients who had a final diagnosis were included. Patients with MND other than ALS were excluded. We used IBM SPSS 19 for statistical analysis. Results: Of 368 patients, 43 (11.7%) were diagnosed with ALSms. Compressive myelopathy was the most frequently diagnosed pathology (n=14), followed by peripheral neuropathy (n=7) and inclusion body myositis (n=4). Age and gender distribution were similar in groups ALSms and ALS. Time from the onset to diagnosis was 32.4 months (± 28.1) in ALSms, and 19.7 (± 16.9) in ALS (p In ALSms 27.9% of the patients reported infrequent symptoms for ALS (pain, paresthesia, weight loss) at the onset of the disease, whereas in the ALS group they were observed in 7.3% (p Upper MN involvement was 45% in ALSms group and 82% in ALS (p On EMG of ALSms group there was 23.3 % lower MN involvement, as opposed to 91 % in ALS (p Conclusions: ALSms group presented longer evolution from onset to diagnosis, higher frequency of infrequent symptoms for ALS and lower frequency of upper signs of MN than ALS. Most did not have an EMG compatible with lower MN involvement, as opposite to the ALS group. Time to diagnosis, atypical clinical characteristics and EMG should prompt suspicion of other differential diagnosis. Disclosure: Dr. Segamarchi has nothing to disclose. Dr. Rey has nothing to disclose. Dr. Rodriguez has nothing to disclose.