Akiko Koyama

National Center for Child Health and Development, Edo, Tōkyō, Japan

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Publications (2)2.61 Total impact

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    ABSTRACT: We performed the first nationwide survey of Cockayne syndrome (CS) in Japan, and it suggested that in Japan the incidence of CS is 2.77 per million births (95% confidence interval: 2.19-3.11) and the prevalence of CS is about 1 in 2,500,000. A total of 47 CS patients (24 surviving and 23 deceased) were identified. Based on their clinical courses, these 47 patients were classified into CS type 1 (n = 41, 21 surviving and 20 deceased), CS type 2 (n = 2, all deceased), CS type 3 (n = 3, all surviving), and CS/xeroderma pigmentosum type D (n = 1, deceased). In the 41 CS type 1 cases, seven findings; i.e., a failure to thrive, photosensitivity, deafness, the characteristic facial appearance of CS (sunken eyes), foot joint contracture, intellectual disability, and the detection of basal ganglia calcification on computed tomography (CT) were observed in more than 90% of cases. Of these, a failure to thrive, photosensitivity, and intellectual disability (language delays) developed before 2 or 3 years of age, whereas deafness, sunken eyes, and the appearance of basal ganglia calcification on CT occurred later. Features such as body weight and height stagnation, language delays, abnormal nutritional pathways (tube feeding), and renal failure were more prominent in the 20 deceased CS type 1 patients than in the 21 surviving CS type 1 patients. Of the 20 deceased CS type 1 patients, nine developed severe renal failure during the terminal stages of their condition. Our findings suggest that the clinical course of CS includes a diverse range of symptoms, but each type exhibits characteristics symptoms. In addition, the management of renal failure and nutrition are very important for ensuring a good quality of life throughout the long-term course of CS. This article is protected by copyright. All rights reserved.
    Pediatrics International 04/2015; 57(3). DOI:10.1111/ped.12635 · 0.73 Impact Factor
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    ABSTRACT: Despite the decrease in Reye syndrome after the discontinuation of aspirin, acute encephalopathy (non-Reye syndrome type) has been continually reported in Japan. Recent studies suggested that the thermolabile phenotype of carnitine palmitoyltransferase II (CPT II) variation [F352C] was closely related to the pathomechanism of influenza-associated encephalopathy (IAE) in Japanese, causing mitochondrial ATP utilization failure during periods of high fever, resulting in brain edema. So, we analyzed CPT II polymorphism and peripheral blood ATP levels as a signal of "energy crisis" in 12 and 10 patients with acute encephalopathy, respectively. Out of the 12 patients with acute encephalopathy, six showed thermolabile CPT II variants [F352C], and of these six, two patients died in spite of intensive care. In contrast, the remaining six patients with no thermolabile CPT II variant [F352C] showed a relatively mild clinical course. Blood ATP levels of the 10 patients in the acute phase of encephalopathy were significantly lower than those during the convalescent phase and also those of patients with febrile seizure status. Our data suggest that the thermolabile F352C CPT II variant, found only in Japanese, might be one of the predisposing factors to trigger the pathomechanism of acute encephalopathy in the Japanese population, and that it is causally related to the severity of disease. The decreased blood ATP level seems to reflect systemic mitochondrial dysfunction including the blood brain barrier during the acute phase of encephalopathy.
    Brain & development 01/2011; 34(1):20-7. DOI:10.1016/j.braindev.2010.12.012 · 1.88 Impact Factor