[Neurological CPC.57. An 80-year-old woman with four years history of muscle atrophy involving lower extremities predominantly on the right side].

We report an 80-year-old woman with progressive muscular atrophy predominantly involving her right lower extremity. She was well until 1992 (75 years of age) when she noted an onset of weakness in her right leg which had got progressively worse. She was admitted to our service in July 1994. On admission, general physical examination was unremarkable. She was alert and well oriented without dementia. Higher cerebral functions were normal. Cranial nerves also appeared intact. She dragged her right leg in walking. Mild to moderate weakness (2/5 to 4/5) was noted in muscles in her right lower extremity more in the distal part. Deep tendon reflexes were within normal limits, and the plantar response was flexor bilaterally. Sensation was intact. Laboratory examinations were also unremarkable except for slight increase in CK which was 470 IU/l. CSF was also normal. EMG revealed neurogenic changes in the lower extremities. She was admitted to Aoki Hospital on October 21, 1994, by that time, her weakness in the right lower extremity had gotten worse in that the muscle strength of the right extensor hallucis longus was 0 and tibialis anterior 2; muscle atrophy was also prominent in her right leg; the right ankle jerk could not be elicited. In the subsequent course, weakness and atrophy appeared in her left lower extremity, however, upper extremities and cranial nerves had never been affected. Babinski sign was always negative. In February 1996, she developed delusional ideation of self persecution, and showed difficulty in communication with medical staffs. She developed fever of 38.7 degrees C on June 13, 1996 expired on the next day. The patient was discussed in a neurological CPC, and the chief discussant arrived at the conclusion that the patient had a form of spinal muscular atrophy. Opinions were divided between ALS and spinal muscular atrophy. Post-mortem examination revealed marked loss of anterior horn neurons in the lumbar area with astrogliosis. Bunina bodies were seen in some of the remaining neurons. No myelin pallor was noted in the pyramidal tracts, however, atrophy and loss of Betz cells were noted in the motor cortex. Other cortical areas were unremarkable. The neuropathologist arrived at the conclusion that the patient had ALS. This patient was unique in that she had asymmetric atrophy and weakness limited to the lower extremities. This is quite unusual as ALS of four years duration. In addition, the patient developed some mental change which was thought to represent dementia by some participants. But no clear morphologic changes were seen to account for her mental change.