Akimasa Okuno

Serum melatonin kinetics and long-term melatonin treatment for sleep disorders in Rett syndrome

We studied the circadian rhythm of serum melatonin levels in two patients with classical Rett syndrome having severe sleep disorders; serum melatonin levels were measured before and during melatonin treatment using radioimmunoassay. Patient 1 had a free-running rhythm of sleep-wake cycle from 3 years of age. At the age of 4 years, the peak time of melatonin was delayed 6 h compared to normal control and the peak value was at the lower limit. Patient 2 had a fragmented sleep pattern accompanied by night screaming from 1 year and 6 months of age. At the age of 10 years, the peak time of melatonin secretion was normal but the peak value was at the lower limit. These patients were given 5 mg melatonin orally prior to bedtime. Exogenous melatonin dramatically improved the sleep-wake cycle in patient 1. In patient 2, exogenous melatonin showed a hypnotic effect but early morning awakenings occurred occasionally. When melatonin treatment was stopped, the sleep disorders recurred and re-administration of 3 mg melatonin was effective in both patients. The effect was maintained over 2 years without any adverse effects. These findings suggests that sleep disorders in patients with Rett syndrome may relate with an impaired secretion of melatonin.

Hashimoto encephalopathy: Etiologic considerations

A 15-year-old girl is described with encephalopathy associated with Hashimoto thyroiditis which subsequently developed into autoimmune thyrotoxicosis (hashitoxicosis) and distal renal tubular acidosis at age 5 years, pernicious anemia at age 9, and encephalopathy at age 12. Thyroid hormone levels were within the normal ranges at the time of neurologic presentation. Serum IgG concentration and oligoclonal IgG bands in cerebrospinal fluid closely correlated with the severity of neurologic symptoms. Treatment with glucocorticoids improved the level of consciousness but her mental state continued to deteriorate. Repeated cranial computed tomographic scans revealed progressive symmetric atrophy in the gray matter without infarction. These findings suggest that encephalopathy associated with Hashimoto thyroiditis is caused by an antineuronal antibody-mediated reaction.

Acute suppurative thyroiditis in children

Ten cases of acute suppurative thyroiditis were studied. All patients remained euthyroid clinically during the course of this disease and during the follow-up. Of seven cases in which bacterial cultures were performed, an aerobic bacterium alone was isolated in one patient and anaerobic bacteria alone in four patients. Mixed aerobic and anaerobic microorganisms were recovered from one patient and cultures were negative in one case. Plasma TSH, T4, T3, and PBI levels were normal except in one case. The 131I uptake values were normal in six of seven cases. Plasma TSH response to TRH stimulation was normal in four of five cases. Antibodies against thyroglobulin and thyroid microsome were negative in four of six cases. These findings suggest that anaerobic bacteria may play an important role in the pathogenic process of acute suppurative thyroiditis and that the pituitary-thyroid functions are not impaired.

Encephalopathy associated with haemophagocytic lymphohistiocytosis following rotavirus infection

Abstract A 2-year-old Japanese boy with a haemophagocytic lymphohistiocytosis (HLH) associated encephalopathy which developed after rotavirus infection is described. The neurological symptoms consisted of coma, seizures and spastic quadriplegia. On therapy with steroids, etoposide and cyclosporin A, the patient recovered without any neurological deficits. The interferon-gamma levels in serum and CSF were elevated at onset of the disease but had returned to normal at the time of clinical remission. Brain MRI revealed diffuse white matter abnormalities and parenchymal volume loss. Proton magnetic resonance spectroscopy revealed elevated lactate in the abnormal lesions observed on MRI, indicating that macrophages not exhibiting aerobic metabolism had infiltrated the CNS. At the time of clinical remission, the white matter abnormalities and brain lactate had disappeared. These findings suggested that the neurological symptoms resulted from the overproduction of cytokines by activated T-cells and macrophages. The pathophysiology of a HLH associated encephalopathy was considered to be a local immune response within the CNS, because interferon-gamma can induce the expression of major histocompatibility complex class I and II antigens on glial cells in the CNS. Conclusion Haemophagocytic lymphohistiocytosis associated encephalopathy should be considered early in the differential diagnosis of cases with acute onset neuropathy.

Descriptive Epidemiology of IDDM in Hokkaido, Japan: The Childhood IDDM Hokkaido Registry

OBJECTIVE To identify the incidence of IDDM with regard to sex, age, family history of diabetes, season, and 5-year period of childhood IDDM among children ages 0–14 years from a population-based epidemiological study in Hokkaido, Japan, from 1973 to 1992. RESEARCH DESIGN AND METHODS Registration of all new IDDM cases in Hokkaido was conducted by the Childhood IDDM Hokkaido Registry Study Group from 1973 to 1992. The cases were selected from among 1) patients who were admitted to the member hospitals of the study group, 2) patients who answered a questionnaire distributed to hospitals and diabetic clinics throughout Hokkaido, and 3) patients whose cases were recorded in free-treatment medical records of urban and rural districts. The case ascertainment rate was estimated to be 100%. Differences in incidence with regard to sex, age, family history of diabetes, season, and year period were analyzed by the Poisson regression analysis by GENMOD. RESULTS During the 20-year period studied, 396 cases (181 boys, 215 girls) of abruptonset IDDM were registered. Statistically significant differences in annual incidence were found according to sex (female), age (8–14 years), history (having no diabetes in family), season (spring), and 5-year period. CONCLUSIONS This is the first population-based, long-term epidemiological study of childhood IDDM from Japan. We observed a significantly higher annual incidence (per 100,000/year) of IDDM in female subjects (1.81), older age-groups (2.25 for 8–14 years), subjects with no family history of diabetes (1.26), diabetes onset in the spring (2.20), and an increased trend over the 20 years. In addition, the heterogeneity of IDDM among Japanese children needs to be elucidated.

Urine Growth Hormone Determinations Compared with Other Methods in the Assessment of Growth Hormone Secretion

Okuno, A., Yano, K., Itoh, Y., Hashida, S., Ishikawa, E., Mohri, Z‐I. and Murakami, M. (Department of Paediatrics, Asahikawa Medical College, Hokkaido; Medical College of Miyazaki, Kiyotake, Miyazaki; and Research and Development Division, Sumitomo Pharmaceuticals Co Ltd, Hyogo, Japan). Urine growth hormone determinations compared with other methods in the assessment of growth hormone secretion. Acta Paediatr Scand [Suppl] 337:74, 1987.

Intrafamilial phenotypic variability in Engelmann disease (ED): are ED and Ribbing disease the same entity?

We report on clinical and radiologic manifestations in a 3-generation Japanese family with Engelmann disease (ED) or progressive diaphyseal dysplasia. A large variation of phenotype was remarkable among 12 affected family members. Of the 12 patients, 7 had full manifestations of ED, such as bilateral, symmetrical diaphyseal sclerosis of long bones with myopathy and limb pain, whereas the other 5 exhibited only segmental (rhizomelic and/or mesomelic) involvement and asymmetric diaphyseal sclerosis without any clinical symptoms. The phenotype of the latter group of patients resembled Ribbing disease (RD). We propose that ED and RD represent phenotypic variation of the same disorder.

Proton magnetic resonance spectroscopy to study the metabolic changes in the brain of a patient with Leigh syndrome.

Localized proton magnetic resonance spectroscopy (MRS) was performed to study the metabolic changes in the brain of a patient with Leigh syndrome, who had a T-->G point mutation at nt 8993 of mitochondrial DNA. In this patient, sodium dichloroacetate therapy normalized the lactate and pyruvate levels in both blood and cerebrospinal fluid (CSF). However, his psychomotor retardation did not improve and magnetic resonance imaging showed progressive cerebral atrophy. In the patients spectra, elevation of brain lactate was observed throughout the brain with regional variations, predominantly in the basal ganglia and brainstem with an abnormal MRI appearance. Although the lactate/creatine ratio observed on proton-MRS was related to the CSF lactate level, the ratio did not completely parallel the CSF lactate level, i.e. brain lactate was detected even when the CSF lactate level had become normalized. Furthermore, proton-MRS revealed a decrease in the N-acetylaspartate/creatine ratio and an increase in the choline/creatine ratio, representing neuronal loss and breakdown of membrane phospholipids. The clinical and MRI findings were well related to the changes in spectroscopically determined brain metabolites. These results indicate that the brain metabolites observed on proton-MRS are useful indicators of a response to therapy and prognosis in Leigh syndrome.

Clinical significance of cytokine measurement for detection of meningitis

Levels of interleukin-6 and tumor necrosis factor alpha were measured in cerebrospinal fluids from patients with meningitis. Interleukin-6 was increased in aseptic and bacterial meningitis, whereas tumor necrosis factor alpha was increased only in bacterial meningitis. We concluded that measurement of cytokines in cerebrospinal fluid may be useful for the rapid diagnosis of meningitis.

Kabuki make-up syndrome is not caused by microdeletion close to the Van der Woude syndrome critical region at 1q32-q41

We reported on a 5-year-old Japanese girl with clinical manifestations of Kabuki make-up syndrome (KMS) and van der Woude syndrome (VWS). Since the concurrence of the two syndromes is known in four patients, including ours, it suggests a common cause. Assuming that the association of the two syndromes was caused by a microdeletion involving the putative KMS/VWS genes, we carried out fluorescence in situ hybridization and microsatellite analyses using PAC clones and dinucleotide repeat markers spanning the VWS1 critical region at 1q32-q41. No deletion was detected at the VWS1 critical region.