RESUMO
ALS is a neurodegenerative disease due to degeneration of both upper and lower motor neurons [UMN and LMN]. There is no treatment for this disorder and it is important to distinguish from other conditions that may mimic ALS. This is a descriptive study since September 2002 until September 2004 among the patients whom referred to neurology department of Ghaem hospital. 21 patients were studied [14 men]. Mean age was 41.58 years. UMN and LMN symptoms were the presenting complaint of our patients except 5 cases with bulbar onset. Symptoms began before age of 40 in 40% of our all patients, and 27% of Charcot type of ALS. 15 Cases had charcot type of ALS, 4 cases had juvenile ALS, 1 case had Kennedy syndrome and finally 1 case had Madras motor neuron disease [MMND]. In this study we found the first case of MMND in Iran. There was a large proportion [40%] of cases with age of onset below 40 years in comparison with previous studies, more epidemiological and toxicological studies should be done