Assessment of risk factors for non-specific chronic disabling low back pain in Japanese workers-findings from the CUPID (Cultural and Psychosocial Influences on Disability) study.

The majority of patients with non-specific low back pain (LBP) suffer from chronic pain. Psychosocial factors play an important role in the chronicity of LBP. To explore the risk factors for chronic disabling LBP in detail, we assessed its various risk factors in Japanese workers, using data from the Cultural and Psychosocial Influences on Disability (CUPID) study. Data were drawn from a 1 yr follow-up of 20‒59 yr-old workers who participated in the CUPID study. A self-administered questionnaire assessed various factors, including individual characteristics, ergonomic work demands, and work-related or other psychosocial factors. Logistic regression analyses were performed to assess the associations between these factors and chronic disabling LBP. Of 198 participants, 35 (17.7%) had chronic disabling LBP during the 1 yr follow-up. Multivariate logistic regression analysis revealed that the interaction effect of the two factors, expectation of LBP problems and excessive working hours (≥ 60 h per week), was associated with chronic disabling LBP. Chronic disabling LBP was present in 42.5% of participants with both of these two risk factors, whereas it was present in 11.8% of participants without these risk factors. In conclusion, among various factors, the combination of two psychosocial factors was particularly associated with chronic disabling LBP.

Coenzyme Q10 therapy in hereditary motor sensory neuropathy type VI with novel mitofusin 2 mutation.

Hereditary motor sensory neuropathy type VI (HMSN VI) is hereditary neuropathy accompanied by optic neuropathy. The feasibility of Coenzyme Q10 (CoQ10) as a treatment for subacute visual impairment of HMSN VI was examined. A 37-year-old patient with HMSN VI with a novel mitofusin 2 mutation was treated with high dose of CoQ10 (200 mg/day) for eight months. Visual impairment was partially resolved after CoQ10 therapy. High dose CoQ10 therapy may improve the prognosis of subacute visual impairment in HMSN VI. To confirm the effectiveness of CoQ10 on HMSN VI, further studies are needed.

Cervical pachymeningeal hypertrophy as the initial and cardinal manifestation of mucopolysaccharidosis type I in monozygotic twins with a novel mutation in the alpha-L-iduronidase gene.

We describe a pair of monozygotic twins with an attenuated form of mucopolysaccharidosis type I (MPS-I). At age 24, they both developed cervical myelopathy as a cardinal manifestation. They each also had mild valve abnormalities and both inguinal and umbilical hernia, however, other characteristic features of MPS-I were absent or very mild. Magnetic resonance imaging revealed the cervical cord compressed by pachymeningeal hypertrophy. Surgery with dural plasty and laminoplasty resulted in decompression of the cervical cord with clinical improvement, revealing marked thickening of the dura mater. Both patients showed a marked decrease of alpha-L-iduronidase (IDUA) activity with c.252insC (p.P55fsX62; known) and c.1209C>A (p.T374N; novel) mutations of the IDUA gene (IDUA). Patients with MPS-I have been reported to present with various clinical phenotypes and severities even if they have identical mutations of IDUA. The quite similar, unique phenotype in monozygotic twins suggests that not only IDUA mutation but also other genetic factors than IDUA markedly influence the clinical manifestations of MPS-I.

Prevalence of spinocerebellar degenerations in the Hokuriku district in Japan.

BACKGROUND: The prevalence of disease subtypes of spinocerebellar degenerations (SCDs) varies between countries, and even between areas within a country. We report unprecedented epidemiologic data on SCDs in the Hokuriku district, which is located in the central, western part of Japan. METHODS: Clinical and genetic data on SCD patients were obtained via questionnaires distributed to all the departments of neurology, psychiatry and internal medicine in the Hokuriku district (n = 418). RESULTS: Among the SCD patients, autosomal dominant cerebellar ataxias (ADCAs) were noted in 40.4%, multiple system atrophy in 24.7%, cortical cerebellar atrophy in 13.3% and autosomal recessive cerebellar ataxia in 0.3%. Genetically confirmed ADCA patients included those with Machado-Joseph disease (MJD)/spinocerebellar ataxia type 3 (SCA3; 63.3%), SCA6 (20.0%), ADCA linked to chromosome 16q22.1 (10.0%), dentatorubral pallidoluysian atrophy (4.4%), SCA1 (1.1%) and SCA2 (1.1%). MJD/SCA3 was highly prevalent in the Toyama prefecture of the Hokuriku district, accounting for 90% of genetically confirmed ADCAs by birthplace; MJD/SCA3 patients were concentrated in the Gosei area, the western part of the Toyama prefecture, giving an estimated prevalence of 19.1 per 100,000 inhabitants. CONCLUSIONS: The Hokuriku district, especially the Gosei area of Toyama, had a surprisingly high relative frequency and prevalence of MJD/SCA3, which is comparable to that in the Azores, Portugal.

Epidemiology of familial amyloid polyneuropathy in Japan: Identification of a novel endemic focus.

BACKGROUND: Familial amyloid polyneuropathy (FAP) is distributed worldwide with several endemic foci including two major foci in Japan. OBJECTIVE: To elucidate a nationwide epidemiology of FAP in Japan. DESIGN, SETTING, AND PATIENTS: (i) We analyzed the data of FAP patients registered by the Ministry of Health, Labour, and Welfare, Japan, during 2003-2005. (ii) As Ishikawa prefecture was found to be a novel endemic focus, we examined 27 FAP patients in Ishikawa to characterize their clinical and genetic features in comparison with other endemic foci. RESULTS: (i) The prevalence of familial amyloidosis in Japan was estimated to be 0.87-1.1 per 1,000,000 persons. Nagano prefecture had the highest prevalence (11-15.5), followed by Kumamoto (10.1-10.3), and then Ishikawa (3.5-4.2). (ii) All the FAP patients in Ishikawa had transthyretin (TTR) type FAP; all the families had a TTR Val30Met mutation except one family with a Leu58Arg mutation. FAP with Val30Met mutation in Ishikawa was characterized by late onset, high penetrance, and moderate autonomic dysfunction. CONCLUSIONS: Ishikawa prefecture is the third endemic focus of FAP in Japan. FAP with TTR Val30Met mutation in Japan can be classified to (i) early-onset and endemic (Nagano and Kumamoto), (ii) late-onset and endemic (Ishikawa), and (iii) late-onset and non-endemic types.

B-cell neurolymphomatosis confined to the peripheral nervous system.

Patients with neurolymphomatosis show lymphoma cells within the peripheral nerves, nerve root/plexus, or cranial nerves. However, most neurolymphomatosis patients show lymphomatous infiltration not only in the peripheral nervous system (PNS), but also in the meninges, Virchow-Robin space, and brain parenchyma. Here, we report a 74-year-old woman with diffuse large B-cell lymphoma presenting with motor-sensory-autonomic polyneuropathy and multiple cranial neuropathies. A diagnosis of neurolymphomatosis was made by sural nerve biopsy. Postmortem examination indicated that lymphoma cell infiltration in the nervous system was confined to the PNS with no involvement of the central nervous system, including the meninges. This was a very rare case of B-cell neurolymphomatosis with lymphomatous infiltration confined to the PNS, suggesting specific affinity of the lymphoma cells for the PNS in this patient.