Pervasive Developmental Disorders and Autism Spectrum Disorders: Are These Disorders One and the Same?

The concept of pervasive developmental disorders (PDD) and autism spectrum disorders (ASD) closely resemble each other. Both ICD-10 and DSM-IV use the term PDD. The authors surveyed the perception of PDD/ASD and attitudes toward terminology. The subjects of this study were 205 medical/social-welfare professionals working in fields relating to developmental disorders. Questionnaires were mailed to site investigators at the collaborating institutes. With regard to what the scope of ASD and PDD encompasses, the answers were almost equally divided among three views: ASD and PDD are the same, PDD is wider in scope and ASD is wider. The terms PDD and autism were used in slightly different ways depended upon the situation. Our results demonstrate that the parameters of PDD and ASD are unclear and that the terms related to PDD/ASD are often used differently. Further studies are required to develop more clear and reliable diagnostic criteria for PDD.

Imaging Improves Diagnosis of Dementia with Lewy Bodies

Dementia with Lewy bodies (DLB) is the second most common cause of degenerative dementia after Alzheimer's disease (AD), and is clinically characterized by the progressive cognitive decline with fluctuations in cognition and alertness, recurrent visual hallucinations and Parkinsonism. Once these characteristic symptoms of DLB emerge, discriminating it from AD is relatively easy. However, in the early disease stages, the clinical symptoms of various types of dementias largely overlap and it is difficult to distinguish DLB from other neurodegenerative dementias based on clinical manifestations alone. To increase the accuracy of antemortem diagnosis of DLB, the latest diagnostic criteria incorporate findings from 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, or from neuroimaging such as computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and positron emission tomography (PET). In the present guidelines, decreased dopamine transporter uptake revealed by SPECT or PET receives the greatest importance among various neuroimaging findings and is listed as one of the suggestive features. Supportive features that commonly present but are not proven to have diagnostic specificity include relatively-preserved medial-temporal-lobe structures, occipital hypoperfusion, and abnormal MIBG myocardial scintigraphy. In this paper, we review the major findings on various neuroimaging modalities and discuss the clinical usefulness of them for the diagnosis of DLB. Although there is not enough evidence to reach the conclusion, considering the accessibility in clinical practice, in our personal views, we recommend the use of brain-perfusion SPECT and MIBG myocardial scintigraphy to improve the diagnosis of DLB.

Imaging Improves Diagnosis of Dementia with Lewy Bodies

Dementia with Lewy bodies (DLB) is the second most common cause of degenerative dementia after Alzheimer's disease (AD), and is clinically characterized by the progressive cognitive decline with fluctuations in cognition and alertness, recurrent visual hallucinations and Parkinsonism. Once these characteristic symptoms of DLB emerge, discriminating it from AD is relatively easy. However, in the early disease stages, the clinical symptoms of various types of dementias largely overlap and it is difficult to distinguish DLB from other neurodegenerative dementias based on clinical manifestations alone. To increase the accuracy of antemortem diagnosis of DLB, the latest diagnostic criteria incorporate findings from 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, or from neuroimaging such as computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and positron emission tomography (PET). In the present guidelines, decreased dopamine transporter uptake revealed by SPECT or PET receives the greatest importance among various neuroimaging findings and is listed as one of the suggestive features. Supportive features that commonly present but are not proven to have diagnostic specificity include relatively-preserved medial-temporal-lobe structures, occipital hypoperfusion, and abnormal MIBG myocardial scintigraphy. In this paper, we review the major findings on various neuroimaging modalities and discuss the clinical usefulness of them for the diagnosis of DLB. Although there is not enough evidence to reach the conclusion, considering the accessibility in clinical practice, in our personal views, we recommend the use of brain-perfusion SPECT and MIBG myocardial scintigraphy to improve the diagnosis of DLB.

Biological Studies on Alcohol-Induced Neuronal Damage

Alcohol is a well-known cytotoxic agent which causes various kinds of neuronal damage. In spite of thousands of published studies, the true mechanism of alcohol-induced neuronal damage remains unclear. Neurogenesis is the generation of neurons from neural stem cells (NSCs) and occurs in predominantly two regions of the brain, the subventricular zone and the dentate gyrus of the hippocampus. NSCs are the self-renewing, multipotent precursor cells of neurons, astrocytes, and oligodendrocytes in the central nervous system. Recent studies have begun to illuminate the role of neurogenesis in the biological and cellular basis of psychiatric disorders and several clinical symptoms seen in alcoholism such as depression, cognitive impairment, underlying stress and brain atrophy have been linked to impaired neurogenesis. Heavy alcohol consumption decreases neurogenesis in animals, while in vitro studies have shown decreased generation of new neurons after alcohol exposure. These findings suggest that decreased neurogenesis is important in the pathophysiology of alcoholism. Neurogenesis can be divided into four stages; proliferation, migration, differentiation and survival. Our in vitro studies on NSCs showed that alcohol decreased neuronal differentiation at doses lower than those that affected cell survival and suggested that neuron-restrictive silencer factor, or repressor element-1 silencing transcription factor (NRSF/REST) could be involved in alcohol-induced inhibition of neuronal differentiation. In an animal model of fetal alcohol effects behavioral symptoms improved after NSC transplantation. Neurogenesis could be the target for new strategies to treat alcohol related disorders.

Pooling System for Multiple-Choice Questions for the National Examination for Medical Practitioners. Results of a Field Study in Japan / 医学教育

The Ministry of Health and Welfare of Japan is planning a pooling system for multiple-choice questions (MCQs) for the national examination for medical practitioners. To clarify possible problems of such a system, a field study was performed by 10 medical schools in Japan using 90 MCQs from previous examinations. Nine hundred twenty-four 6th-year students participated in the field test. For each MCQ, the correct-response rates at the originating school and those obtained in the field test were significantly correlated. Thus, the correct-response rates to questions on the field test could be predicted from the rates at the originating schools. However, for each question the correct-response rate was significantly higher for students of the originating school than for students of other schools. In the national examination, care should be taken to prevent differences in scores on the basis of question sources.

Results of a Survey on Clinical Competence to Be Evaluated by the National Physicians' License Examination / 医学教育

The clinical competence needed by every beginning resident and the present status of such competencewere examined in August 1998 through questionnaires distributed to clinical educators and the nursing staff of university hospitals and clinical training hospitals designated by the Ministry of Health and Welfare. Completed questionnaires were returned by 576 (65.9%) of clinical educators and nursing staff. With a cluster analysis of the necessity and the present status of clinical competence, 21 items for clinical competence were identified as those most requiring evaluation by the national examination. These 21 items included 11 items for clinical competence in the cognitive domain, 8 items in the psychomotor domain, and 2 in the affective domain. In about half of the direct answers obtained from clinical educators, evaluations were considered necessary for 15 items of clinical competence, of which 13 belonged to the cognitive domain. These results were consistent with the present status. However, practical examinations have also attracted increasing attention, as the results included strong demands that the national examination evaluate some basic clinical skills, such as physical examination and measurement of vital signs. However, about 30 % of authorities governing the national examination thought no changes are needed in the national examination.

Medical education system. Report of the Working Group on the Medical Education System / 医学教育

The working group on the medical education system in the Japan Society for Medical Education had 2 meetings in 1997. In those meetings, members of the working group discussed on the following 4 problems related to the medical education;<BR>1) System to accept the graduates of other departments (Gakushi) into medical school<BR>2) Clinical professorship<BR>3) Post-graduate universities<BR>4) Education in the department of general medicine (Sogo-shinryo-bu)<BR>The results of the discussions are reported.