Epidemiological study of acute encephalitis in Tottori Prefecture, Japan.

BACKGROUND AND PURPOSE: To conduct an epidemiological survey of acute encephalitis focusing on non-herpetic acute limbic encephalitis (NHALE) in Tottori Prefecture, western area of Japan. METHODS: A questionnaire survey on the annual number of patients aged 16 years or more with acute encephalitis from 2001 to 2005 was undertaken in 2006. RESULTS: During the study period, 49 patients were diagnosed with acute encephalitis. The subtype of acute encephalitis was as follows: 10 patients with herpes simplex encephalitis (HSE), 12 patients with NHALE, 4 patients with paraneoplastic encephalitis, 2 patients with encephalitis associated with collagen disease, one patient with viral encephalitis other than HSE, 20 patients with encephalitis with unknown causes. The service-based incidence rate of acute encephalitis was 19.0 per million person-years. The incidence rate of NHALE subtype was 4.7 per million person-years. CONCLUSIONS: Our epidemiological survey indicated an estimated 550 patients would develop NHALE per year in Japan, suggesting that NHALE may not be a rare disorder.

An axonal form of Charcot-Marie-Tooth disease showing distinctive features in association with mutations in the peripheral myelin protein zero gene (Thr124Met or Asp75Val).

OBJECTIVES AND METHODS: Seven families were studied with an axonal form of Charcot-Marie-Tooth disease (CMT) associated with mutations in the peripheral myelin protein zero (MPZ) gene-Thr124Met or Asp75Val. RESULTS: Patients with these mutations commonly showed relatively late onset sensorimotor neuropathy predominantly involving the lower limbs. Sensory impairment typically was marked, and distal muscle atrophy and weakness were also present in the legs. Adie's pupil and deafness were often present, and serum creatine kinase concentrations were often raised irrespective of which MPZ mutation was present. Relatively well preserved motor and sensory nerve conduction velocities contrasted with reduced or absent compound muscle action potentials and sensory nerve action potentials. Axonal change with marked axonal sprouting was seen in sural nerve specimens. CONCLUSION: The similar associated clinical findings suggest that patients with axonal CMT with an MPZ gene mutation share distinctive clinical features.

[A case of supranuclear hypoglossal nerve palsy with Avellis' syndrome due to a medullary infarction].

We reported a 72-year-old man with left supranuclear hypoglossal nerve palsy and right Avellis' syndrome due to a medullary small infarction. On admission, he showed slight disturbance of consciousness, ocular lateropulsion to the right side, rotatory nystagmus, dysarthria, absent right gag reflex, curtain sign, absent right palatal reflex, deviation of the uvula toward the left side, raise of only the left palate when the patient attempted to utter, paralysis of the right vocal cord and deviation of the tongue toward the left side. Neither atrophy nor fasciculation was observed on the tongue. 124 days after the onset, he had only the left supranuclear hypoglossal nerve palsy and right Avellis' syndrome. MRI showed a small lesion in the medulla, so lateral area of the medulla and a part of the reticular formation medial to the nucleus ambiguous presumed to be involved. These findings suggest that supranuclear pathway to the hypoglossal nucleus of the opposite side exists in the reticular formation near nucleus ambiguous.

Recurrent herpes zoster myelitis treated with human interferon alpha: a case report.

Recurrent herpes zoster myelitis is very rare. However, a case was recently observed in our hospital. A 43-year-old woman developed myelitis 2 weeks after development of shingles. Her condition was improved by methylprednisolone. Seven months later, she developed myelitis after development of shingles again. Antibody against varicella-zoster (VZV), increased in the serum, but was negative in the cerebrospinal fluid. Methylprednisolone was not sufficiently effective against this attack. The refractory sensory disturbance was improved by human interferon alpha (IFN-alpha). Natural killer cell activity, the helper T-cell/suppressor T-cell ratio and the kappa/lambda ratio of B-cells increased with clinical improvement. In this case, delayed-type hypersensitivity after VZV infection played a role in the occurrence of myelopathy and clinical improvement resulted from the immunosuppressive effects of IFN-alpha.

Treatment of tension-type headache with tizanidine hydrochloride: its efficacy and relationship to the plasma MHPG concentration.

Seventy-eight patients with tension-type headache (TH) were treated with tizanidine hydrochloride (tizanidine). Plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) and serum free fatty acids (FFA) levels in these patients were determined before the treatment with tizanidine. Eighteen healthy volunteers composed the control group. Four weeks after the treatment with tizanidine 24 (31%) of 78 patients showed excellent improvement (excellent group); 28 (35%) showed moderate improvement (moderate group); 18 (23%) showed mild improvement (mild group); 7 (10%) showed no improvement and one (1%) showed worsening of her headache (no change and worsened group). The plasma MHPG levels in the excellent group were significantly higher than in the other groups, including the control group. The serum FFA levels in the excellent group were significantly higher than in the controls. In this study, 66% of the patients reported improvement in their headaches. Some patients with TH had high plasma MHPG levels and these patients in particular showed excellent improvement after the administration of tizanidine. Though there may be a placebo response to some extent, the clinical usefulness of tizanidine for TH seems to be excellent. Further study is necessary concerning the pharmacological effect of tizanidine and plasma MHPG levels in patients with TH.

A neuroendocrinological study in female migraineurs: prolactin and thyroid stimulating hormone responses.

To evaluate the change of the neurotransmitter function in migraine, a neuroendocrinological study was performed in eleven female migraineurs and nine female controls. Thyrotropin releasing hormone, luteinizing hormone releasing hormone, and insulin were simultaneously loaded (the Triple test). Before and after loading, serum glucose, prolactin (PRL), thyroid stimulating hormone (TSH), luteinizing hormone, follicle stimulating hormone, adrenocorticotropic hormone, cortisol, human growth hormone and beta-endorphin were measured. The Triple test produced an increase of PRL in both migraine and control groups, but in migraineurs the increase was significantly larger than in controls. TSH also increased in response to the test, but the TSH response in patients was less than in controls, although not significantly so. The responses of other substances showed no significant differences between the two groups. Although dopaminergic hypofunction in migraine has been proposed by some authors, the present findings rather suggest a serotonergic hyperfunction.

Characterization of the course of senile dementia of the Alzheimer type using cerebrospinal fluid levels of acetylcholinesterase and somatostatin.

Through an epidemiological survey, we observed 3 types of clinical courses among patients with senile dementia of the Alzheimer type (SDAT). The mental ability of the patients declined rapidly (Group A; n = 11), gradually (Group B; n = 6), or showed extremely slow changes (Group C; n = 9). The acetylcholinesterase (AChE) activity and somatostatin (SRIF) concentration of the cerebrospinal fluid (CSF) were measured in patients with Alzheimer's disease (AD) and 3 types of SDAT. Both AChE activity and SRIF concentration of CSF were significantly lower in Group A and among patients with AD compared with age-matched control subjects. Both AChE activity and SRIF concentration of CSF were not significantly different in Groups B and C. This biochemical study confirmed our epidemiological finding that only the patients in Group A with SDAT closely resembled the clinical course of AD and may belong to the category of neurodegenerative disorders.

Apolipoprotein abnormalities in dementia.

The serum levels of apolipoprotein B, C-II and the ratio of apolipoprotein B/A-I were found to be significantly higher in multiinfarct dementia than in dementia of the Alzheimer type. The high serum levels of apolipoprotein B, C-II and the high ratio of apolipoprotein B/A-I may cause multiinfarct dementia. The large difference between the groups suggests that the serum levels of apolipoprotein B, C-II and the ratio of apolipoprotein B/A-I may be useful in differential diagnosis of these two kinds of dementia.