[An 84-year-old woman with progressive mental deterioration and abnormal behavior]

We report an 84-year-old woman with progressive mental deterioration. She was well until January 1994, when she was 80 years of the age. At that time she developed a delusional ideation, in that she stated that she would be killed by her fellow members of the society for elderly, in which she was belonging. At times, she closed the shutter of her house saying that a stranger was wandering outside of her house. In 1995, she could not identify the face of her son's wife. When she went out for shopping, she lost her way to the home. She prowled about in and out of her home. In 1996, she had to be admitted to a nursing home, where quarrelled with other patients and behaved violently. She was admitted to the neurology service of Hatsuishi Hospital on November 20th, 1997. Family history revealed that her mother was said to be demented. On admission, she was alert and behaved in a good manner. She was disoriented to the time and unable to do serial 7. Her memory was very poor. She did not show aphasia or apraxia. Cranial nerves appeared to be intact. She showed no weakness or muscle atrophy. Gait was normal for her age. Plastic rigidity was noted in four limbs more on the right side. No ataxia was noted. Deep tendon reflexes were exaggerated, however, no Babinski sign was noted. Sensory examination was intact. Her hospital course was characterized by the development of progressive gait disturbance, violent behaviour, and prowling around. On November 30th, 1998, she fell down and suffered from a fracture in the neck of her femur. Although replacement of the femur head was performed, she became unable to walk after this episode. Her mental functions deteriorated further. She developed pneumonia and expired on February 2, 1999. She was discussed in a neurological CPC and the chief discussant arrived at a conclusion that the patient probably had diffuse Lewy body disease, because of the combination of dementia and parkinsonism. Other possibilities discussed in the CPC included Pick's disease, frontotemporal dementia and parkinsonism, and Alzheimer's disease. Post-mortem examination revealed moderate atrophy in the frontal and temporal cortices. Microscopic examination showed atrophy and gliosis in the hippocampus. Many diffuse plaque and neuritic plaques were seen in the frontal cortex by methenamine silver staining. Neurofibrillary tangles were also found. The Meynert nucleus was preserved. The putamen and the substantia nigra were also intact. Pathologic diagnosis was consistent with Alzheimer's disease.