Ken Sakushima

Diagnostic accuracy of cerebrospinal fluid lactate for differentiating bacterial meningitis from aseptic meningitis: A meta-analysis

OBJECTIVES Cerebrospinal fluid (CSF) lactate is produced by bacterial anaerobic metabolism and is not affected by blood lactate concentration, an advantage over CSF glucose in differentiating bacterial meningitis from aseptic meningitis. However, the previous investigations have shown mixed results of the sensitivity and specificity. Our studys purpose was to assess the utility of CSF lactate in differentiating bacterial meningitis from aseptic meningitis. METHODS We searched MEDLINE and EMBASE for clinical studies that included CSF lactate measurement in bacterial meningitis and aseptic meningitis. Test characteristics were pooled using hierarchical summary ROC curve and random effects model. RESULTS Thirty three studies were included. The pooled test characteristics of CSF lactate were sensitivity 0.93 (95% CI: 0.89-0.96), specificity 0.96 (95% CI: 0.93-0.98), likelihood ratio positive 22.9 (95% CI: 12.6-41.9), likelihood ratio negative 0.07 (95% CI: 0.05-0.12), and diagnostic odds ratio 313 (95% CI: 141-698). Pretreatment with antibiotics lowered the sensitivity 0.49 (95% CI: 0.23-0.75). CSF lactate of around 35 mg/dl (34-36 mg/dl) had higher sensitivity and specificity than those of around 27 mg/dl (26-28 mg/dl). CONCLUSIONS CSF lactates high negative likelihood ratio may make it useful for ruling out bacterial meningitis though pretreatment with antibiotics reduces clinical accuracy. CSF lactate of 35 mg/dl could be optimal cut-off value for distinguishing bacterial meningitis from aseptic meningitis.

3D neuromelanin-sensitive magnetic resonance imaging with semi-automated volume measurement of the substantia nigra pars compacta for diagnosis of Parkinson’s disease

IntroductionNeuromelanin-sensitive MRI has been reported to be used in the diagnosis of Parkinson’s disease (PD), which results from loss of dopamine-producing cells in the substantia nigra pars compacta (SNc). In this study, we aimed to apply a 3D turbo field echo (TFE) sequence for neuromelanin-sensitive MRI and to evaluate the diagnostic performance of semi-automated method for measurement of SNc volume in patients with PD.MethodsWe examined 18 PD patients and 27 healthy volunteers (control subjects). A 3D TFE technique with off-resonance magnetization transfer pulse was used for neuromelanin-sensitive MRI on a 3T scanner. The SNc volume was semi-automatically measured using a region-growing technique at various thresholds (ranging from 1.66 to 2.48), with the signals measured relative to that for the superior cerebellar peduncle. Receiver operating characteristic (ROC) analysis was performed at all thresholds. Intra-rater reproducibility was evaluated by intraclass correlation coefficient (ICC).ResultsThe average SNc volume in the PD group was significantly smaller than that in the control group at all the thresholds (P < 0.01, student t test). At higher thresholds (>2.0), the area under the curve of ROC (Az) increased (0.88). In addition, we observed balanced sensitivity and specificity (0.83 and 0.85, respectively). At lower thresholds, sensitivity tended to increase but specificity reduced in comparison with that at higher thresholds. ICC was larger than 0.9 when the threshold was over 1.86.ConclusionsOur method can distinguish the PD group from the control group with high sensitivity and specificity, especially for early stage of PD.

Nationwide survey on the epidemiology of syringomyelia in Japan

BACKGROUND Syringomyelia is a rare disease characterized by abnormal fluid-filled cavities within the spinal cord, and is associated with Chiari malformations, arachnoiditis, or spinal cord tumors. The widespread availability of magnetic resonance imaging (MRI) in Japan has allowed for easy identification of syrinxes. The aim of this study was to survey the clinicoepidemiological characteristics of syringomyelia in Japan. METHODS A 2-stage postal survey was conducted in late 2009. The first survey aimed to estimate the number of patients with syringomyelia, and the second survey aimed to elucidate clinicoepidemiological characteristics. Diagnosis of syringomyelia was based on the findings of MRI or computed tomographic myelography. RESULTS In the first survey, we received 2133 responses from 2937 randomly selected departments and collected data of 1215 syringomyelia patients (543 men and 672 women). The total response rate for the first survey was 73%. The estimated prevalence of ambulatory syringomyelia patients in Japan was 1.94 per 100000. In the second survey, the proportion of asymptomatic syringomyelia patients was 22.7%. Chiari type I malformations and idiopathic syringomyelia were the first and second most common etiologies. CONCLUSIONS Our nationwide survey indicated that widespread MRI availability has contributed to the diagnosis of both asymptomatic and idiopathic cases.

Clinical features of spinal cord sarcoidosis: analysis of 17 neurosarcoidosis patients

The diagnosis of neurosarcoidosis is often difficult; the imaging signs of spinal cord sarcoidosis sometimes mimic those of cervical spondylotic myelopathy, which is common in elderly persons. We examined the characteristics of spinal cord sarcoidosis in Japanese patients with neurosarcoidosis. This case series identified patients with neurosarcoidosis at four general hospitals and one university hospital from April 1998 to September 2010. All diagnoses were based on the diagnostic criteria proposed by Zajicek et al. Seventeen patients (nine men and eight women) were involved: six patients with spinal cord lesions accompanied by cervical spondylosis, five with cerebral lesions, three with cranial nerve lesions, two with meningitis, and one with nerve root lesions. Patients with spinal cord sarcoidosis had a higher onset age, longer duration from onset to diagnosis, reduced leukocytosis in the cerebrospinal fluid (CSF), and lower angiotensin-converting enzyme (ACE) levels in the CSF. The results of this study indicate that diagnosis of spinal cord sarcoidosis requires careful evaluation.

FDG-PET SUV can distinguish between spinal sarcoidosis and myelopathy with canal stenosis

Spinal cord sarcoidosis is a rare manifestation of sarcoidosis. Magnetic resonance imaging (MRI) of spinal cord sarcoidosis sometimes resembles that of the non-inflammatory spinal cord lesion. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is an effective method to detect both systemic and central nervous system lesions in sarcoidosis. This study compared the standard uptake value (SUV) of FDG-PET between spinal cord sarcoidosis and non-inflammatory spinal cord lesions. We retrospectively reviewed the records of patients who underwent both spinal MRI and FDG-PET scans. We used SUV to evaluate the FDG-PET uptake of the lesion. The region of interest was the center of high-intensity areas on T2-weighted MR images. We included three patients with spinal cord sarcoidosis, five with myelomalacia caused by cervical spondylosis or ossification of the posterior longitudinal ligament, one with spinal cord edema associated with cervical spondylosis, and one with spinal cord edema associated with dural arteriovenous fistula. The spinal cord sarcoidosis group had a significantly higher SUV (mean 4.38, range 3.30–4.93) than patients with the other diseases (mean 1.87, range 1.42–2.74). The SUV of FDG-PET thus may be able to distinguish spinal cord sarcoidosis from other non-inflammatory lesions. FDG-PET can play an important role in the diagnosis of spinal cord sarcoidosis because the gadolinium enhancement in MRI is sometimes seen in spondylotic myelopathy or vascular malformation. FDG-PET is informative for the accurate diagnosis of spinal cord sarcoidosis and may enable clinicians to start treatment at an earlier stage.

Different surgical treatment techniques used by neurosurgeons and orthopedists for syringomyelia caused by Chiari I malformation in Japan

OBJECT Syringomyelia is a rare disease commonly caused by Chiari I malformation. Surgery by neurosurgeons and orthopedists is a critical treatment for symptomatic patients, and surgical techniques are associated with improved symptoms for these patients. The aim of this study was to determine the different surgical techniques used by neurosurgeons and orthopedists in Japan to treat syringomyelia caused by Chiari I malformation. METHODS Patients who had undergone a surgical treatment were identified from a 2-stage postal survey conducted in late 2009. The authors compared the type of surgery performed and its association with cavity size reduction, on the basis of whether patients were receiving care in a neurosurgery or orthopedics department. RESULTS A total of 232 patients with syringomyelia caused by Chiari I malformation were included in this study. Two-thirds of patients were treated in a neurosurgery department and the other third in an orthopedics department. Neurosurgeons preferred foramen magnum decompression (FMD) with dural patch grafting, and orthopedists preferred FMD with dural dissection. Foramen magnum decompression with dural patch grafting was associated with better outcomes than was dural dissection with regard to the following: motor impairment (66% vs. 39%, p < 0.05), sensory disturbance (60% vs. 43%, p = 0.051), pain (67% vs. 47%, p < 0.05), and cavity size (74% vs. 58%, p < 0.05). Improved motor function was associated more with cavity size reduction than with sensory disturbance and pain. CONCLUSIONS Surgical procedures and outcomes differed, depending on whether the patients care was managed in a neurosurgery or orthopedics department. Outcomes were better after FMD with dural patch grafting.

Downbeat positioning nystagmus is a common clinical feature despite variable phenotypes in an FHM1 family

Clinical examinations and mutational analyses were carried out in three patients of a Japanese familial hemiplegic migraine (FHM) pedigree. Each affected member demonstrated a broad clinical spectrum that included hemiplegic migraine with progressive cerebellar ataxia, migraine without aura, and episodic ataxia. Despite this variability, all members exhibited marked downbeat positioning nystagmus, and magnetic resonance images (MRI) all showed cerebellar atrophy predominantly of the cerebellar vermis. All affected members had a T666M missense mutation in the protein encoded by the CACNA1A gene (calcium channel, voltage-dependent, P/Q type, alpha 1A subunit). Although clinical features associated with the T666M CACNA1A mutation are highly variable, downbeat positioning nystagmus may be an important clinical feature of this disease.

Mentoring the next generation of physician-scientists in Japan: a cross-sectional survey of mentees in six academic medical centers

BackgroundPhysician-scientists play key roles in biomedical research across the globe, yet prior studies have found that it is increasingly difficult to recruit and retain physician-scientists in research careers. Access to quality research mentorship may help to ameliorate this problem in the U.S., but there is virtually no information on mentoring in academic medicine in Japan. We conducted a survey to determine the availability and quality of mentoring relationships for trainee physician-scientists in Japan.MethodsWe surveyed 1700 physician-scientists in post-graduate research training programs in 6 academic medical centers in Japan about mentorship characteristics, mentee perceptions of the mentoring relationship, and attitudes about career development.ResultsA total of 683 potential physician-scientist mentees completed the survey. Most reported that they had a departmental mentor (91%) with whom they met at least once a month; 48% reported that they were very satisfied with the mentoring available to them. Mentoring pairs were usually initiated by the mentor (85% of the time); respondents identified translational research skills (55%) and grant writing (50%) as unmet needs. Mentoring concerning long-term career planning was significantly associated with the intention to pursue research careers, however this was also identified by some mentees as an unmet need (35% desired assistance; 15% reported receiving it).ConclusionsMore emphasis and formal training in career mentorship may help to support Japanese physician-scientist mentees to develop a sense of self-efficacy to pursue and stay in research careers.

Adult Leigh Disease Without Failure to Thrive

IntroductionMost Leigh disease (LD) patients die before reaching adulthood, but there are reports of “adult LD.” The clinical features of adult LD were quite different from those in infant or childhood cases. Here, we describe a normally developed patient with adult LD, who presented with spastic paraplegia that was followed several years later by acute encephalopathy. We also conducted a systemic literature search on adult LD and integrated its various manifestations to arrive at a diagnostic procedure for adult LD. Case ReportA 26-year-old woman presented with acute encephalopathy after spastic paraplegia. On her first admission, she exhibited bilateral basal ganglia lesion on magnetic resonance images and normal serum lactate levels. On second admission, she had acute encephalopathy with lactic acidosis and bilateral basal ganglia and brainstem lesions. A muscle biopsy revealed cytochrome c oxidase deficiency, and a diagnosis of adult LD was made. Despite treatment in the intensive care unit, she died 9 days after admission. ConclusionsA review of the literature describing adult LD revealed that developmental delay, COX deficiency, serum lactate elevation, and basal ganglia lesions occurred less frequently than they did in children with LD. Cranial nerve disturbance, pyramidal signs, and cerebellar dysfunction were the primary symptoms in adult LD. Thus, the many differences between childhood and adult LD may be helpful for diagnosing adult LD.

Influence of urinary urgency and other urinary disturbances on falls in Parkinson's disease

INTRODUCTION Falling is one of the most common and serious public health problems. It can cause injuries such as sprains and fractures, and hospitalization may be required for serious injuries. Patients with Parkinsons disease have a higher risk of falls, and urinary incontinence is a known risk factor for falls in the elderly. However, whether other urinary disturbances contribute to the risk of falling remains unclear. The purpose of this study was to identify the association between falls and urinary disturbances in Parkinsons disease. METHODS A prospective cohort study was conducted at a single institution with a 6-month observation period. Subjects were ambulatory patients with Parkinsons disease. Assessments included patient demographics, disease severity measured by the Hoehn and Yahr scale, and urinary disturbances measured using the overactive bladder symptom score (OABSS). Falls were reported using a self-documented fall record. RESULTS A total of 97 patients were included. Forty-four subjects experienced one or more falls during the observation period. The frequency of urination was not related to falling; however, mild urinary urgency, but not severe urinary urgency, increased the risk of falls by an odds ratio of 5.14 (95% confidence interval: 1.51-17.48). Mild urinary urgency was also associated with the time to the first fall and the frequency of falls. One third of falls occurred in the living room, and 13.8% of falls occurred on the way to/from the toilet. CONCLUSION Falls in patients with Parkinsons disease might be associated with urinary urgency, but not with the frequency of urination.