Atypical form of amyotrophic lateral sclerosis

Objective-To investigate patients with an unusual type of muscular atrophy confined to the upper limbs (proximally dominant) and the shoulder girdle, while sparing the face and the legs until the terminal stage. Methods-Eight patients (six men and two women) were clinically examined. Th e age at onset ranged from 42 to 73 years, and the clinical course varied f rom 28 to 81 months. There was no family history of motor neuron disease in any of these patients. Necropsy was performed in two of them. Results-All eight patients basically showed a similar distribution of muscu lar weakness and atrophy Subluxation of the shoulder joints was found in al l patients. Reflexes were absent in the upper limbs in all patients, but we re almost normal in the face and legs in most patients. Pathological reflex es could be elicited in only one patient. Electromyography showed typical n eurogenic changes in the limbs of all patients. Cervical MRI disclosed mode rate spondylotic changes in seven patients. Antiganglioside antibodies were negative in six patients tested. Abnormal trinucleotide (CAG) repeat expan sion of androgen receptor gene was not recognised in five patients examined . Bulbar involvement developed in three patients during the course of the d isease. At necropsy, one patient showed degeneration of the pyramidal tract s and motor cortex including Betz cells as well, as loss of spinal anterior horn cells and brainstem motor neurons, which is consistent with ALS; in a nother patient there was neuronal loss of anterior horn cells at the spinal cord accompanied by astrogliosis, whereas the motor cortex and brainstem m otor nuclei were relatively well preserved. Intracytoplasmic inclusions suc h as Bunina bodies, skein-like inclusions, and Lewy body-like inclusions we re found in both patients. Conclusion-These patients with their peculiar pattern of muscular atrophy s eem to have ALS or a subtype of ALS.