OBJECTIVE To identify the cause of an adult-onset multisystemic disease with multiple deletions of mitochondrial DNA (mtDNA). DESIGN Case report. SETTING University hospitals. PATIENT A 65-year-old man with axonal sensorimotor peripheral neuropathy, ptosis, ophthalmoparesis, diabetes mellitus, exercise intolerance, steatohepatopathy, depression, parkinsonism, and gastrointestinal dysmotility. RESULTS Skeletal muscle biopsy revealed ragged-red and cytochrome- c oxidase-deficient fibers, and Southern blot analysis showed multiple mtDNA deletions. No deletions were detected in fibroblasts, and the results of quantitative polymerase chain reaction showed that the amount of mtDNA was normal in both muscle and fibroblasts. Exome sequencing using a mitochondrial library revealed compound heterozygous MPV17 mutations (p.LysMet88-89MetLeu and p.Leu143*), a novel cause of mtDNA multiple deletions. CONCLUSIONS In addition to causing juvenile-onset disorders with mtDNA depletion, MPV17 mutations can cause adult-onset multisystemic disease with multiple mtDNA deletions.
BACKGROUND Angiotensin II may be involved in amyloid metabolism in the brain. Angiotensin receptor blockers (ARBs) may also prevent cognitive decline. OBJECTIVE To evaluate the impact of treatment with ARBs on the neuropathology of Alzheimer disease (AD) in the National Alzheimer Coordinating Center database, which includes aggregated data and brain autopsies from 29 AD centers throughout the United States. DESIGN Multiple logistic regression was used to compare the pathologic findings in hypertensive subjects taking ARBs with those taking other antihypertensive treatments as well as with hypertensive subjects who did not receive antihypertensive medications. SETTING Neuropathologic data included neuritic plaque and neurofibrillary tangle measures and vascular injury markers. PATIENTS Data were collected from participants who were self-referred or provider-referred and included those with and without cognitive disorders. Our sample included only hypertensive participants and excluded cognitively and neuropathologically normal participants (N = 890; mean age at death, 81 years [range, 39-107 years]; 43% women; 94% white). RESULTS Participants with or without AD who were treated with ARBs showed less amyloid deposition markers compared with those treated with other antihypertensive medications (lower Consortium to Establish a Registry of Alzheimer Disease score: odds ratio, 0.47, 95% CI, 0.27-0.81; Alzheimer Disease and Related Disorders Association score: odds ratio, 0.43, 95% CI, 0.21-0.91; Braak and Braak stage: odds ratio, 0.52, 95% CI, 0.31-0.85; neuritic plaques: odds ratio, 0.59, 95% CI, 0.37-0.96). They also had less AD-related pathology compared with untreated hypertensive subjects. Participants who received ARBs were more likely to have had a stroke; hence, they had more frequent pathologic evidence of large vessel infarct and hemorrhage. CONCLUSION Treatment with ARBs is associated with less AD-related pathology on autopsy evaluations. The effect of ARBs on cognitive decline in those with dementia or AD needs further investigation.
OBJECTIVE To repeat the Clinical vs Neurophysiology (Cl vs N Phys) trial using "unequivocally abnormal" signs and symptoms (Trial 2) compared with the earlier trial (Trial 1), which used "usual" signs and symptoms. DESIGN Standard and referenced nerve conduction abnormalities were used in both Trials 1 and 2 as the standard criterion indicative of diabetic sensorimotor polyneuropathy. Physician proficiency (accuracy among evaluators) was compared between Trials 1 and 2. SETTING Academic medical centers in Canada, Denmark, England, and the United States. PARTICIPANTS Thirteen expert neuromuscular physicians. One expert was replaced in Trial 2. RESULTS The marked overreporting, especially of signs, in Trial 1 was avoided in Trial 2. Reproducibility of diagnosis between days 1 and 2 was significantly (P = .005) better in Trial 2. The correlation of the following clinical scores with composite nerve conduction measures spanning the range of normality and abnormality was improved in Trial 2: pinprick sensation (P = .03), decreased reflexes (P = .06), touch-pressure sensation (P = .06), and the sum of symptoms (P = .06). CONCLUSIONS The simple pretrial decision to use unequivocally abnormal signs and symptoms-taking age, sex, and physical variables into account-in making clinical judgments for the diagnosis of diabetic sensorimotor polyneuropathy (Trial 2) improves physician proficiency compared with use of usual elicitation of signs and symptoms (Trial 1); both compare to confirmed nerve conduction abnormality.
OBJECTIVE To estimate the allele frequency of C9orf72 (G4C2) repeats in amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD), Alzheimer disease (AD), and Parkinson disease (PD). DESIGN The number of repeats was estimated by a 2-step genotyping strategy. For expansion carriers, we sequenced the repeat flanking regions and obtained APOE genotypes and MAPT H1/H2 haplotypes. SETTING Hospitals specializing in neurodegenerative disorders. SUBJECTS We analyzed 520 patients with FTLD, 389 patients with ALS, 424 patients with AD, 289 patients with PD, 602 controls, 18 families, and 29 patients with PD with the LRRK2 G2019S mutation. MAIN OUTCOME MEASURE The expansion frequency. RESULTS Based on a prior cutoff (>30 repeats), the expansion was detected in 9.3% of patients with ALS, 5.2% of patients with FTLD, and 0.7% of patients with PD but not in controls or patients with AD. It was significantly associated with family history of ALS or FTLD and age at onset of FTLD. Phenotype variation (ALS vs FTLD) was not associated with MAPT, APOE, or variability in the repeat flanking regions. Two patients with PD were carriers of 39 and 32 repeats with questionable pathological significance, since the 39-repeat allele does not segregate with PD. No expansion or intermediate alleles (20-29 repeats) were found among the G2019S carriers and AD cases with TAR DNA-binding protein 43-positive inclusions. Surprisingly, the frequency of the 10-repeat allele was marginally increased in all 4 neurodegenerative diseases compared with controls, indicating the presence of an unknown risk variation in the C9orf72 locus. CONCLUSIONS The C9orf72 expansion is a common cause of ALS and FTLD, but not of AD or PD. Our study raises concern about a reliable cutoff for the pathological repeat number, which is important in the utility of genetic screening.
BACKGROUND Prior studies suggest that serotoninergic neurotransmission reduces β-amyloid (Aβ) production. OBJECTIVE To determine whether serotoninergic system degeneration in Parkinson disease promotes Aβ deposition, using in vivo positron emission tomographic probes of serotonin system integrity and Aβ deposition. DESIGN, SETTING, AND PATIENTS Cross-sectional study of 13 subjects with Parkinson disease from the movement disorders clinics at the University of Michigan Health System and Veterans Affairs Ann Arbor Healthcare System, with positron emission tomography using the serotonin transporter ligand carbon 11 ([11C])-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfaryl)-benzonitrile (DASB) and the Aβ ligand [11C]Pittsburgh compound B. RESULTS Inverse correlations were found between DASB and Pittsburgh compound B distribution volume ratios in the neocortex (ρ = -0.577; P = .04) and striatum (ρ = -0.780; P = .002). CONCLUSION Serotoninergic system degeneration in Parkinson disease may promote the development of cerebral amyloidopathy.
BACKGROUND Little is known about adult-onset opsoclonus-myoclonus syndrome (OMS) outside of individual case reports. OBJECTIVE To describe adult-onset OMS. DESIGN Review of medical records (January 1, 1990, through December 31, 2011), prospective telephone surveillance, and literature review (January 1, 1967, through December 31, 2011). SETTING Department of Neurology, Mayo Clinic, Rochester, Minnesota. PATIENTS Twenty-one Mayo Clinic patients and 116 previously reported patients with adult-onset OMS. MAIN OUTCOME MEASURES Clinical course and longitudinal outcomes. RESULTS The median age at onset of the 21 OMS patients at the Mayo Clinic was 47 years (range, 27-78 years); 11 were women. Symptoms reported at the first visit included dizziness, 14 patients; balance difficulties, 14; nausea and/or vomiting, 10; vision abnormalities, 6; tremor/tremulousness, 4; and altered speech, 2. Myoclonus distribution was extremities, 15 patients; craniocervical, 8; and trunk, 4. Cancer was detected in 3 patients (breast adenocarcinoma, 2; and small cell lung carcinoma, 1); a parainfectious cause was assumed in the remainder of the patients. Follow-up of 1 month or more was available for 19 patients (median, 43 months; range, 1-187 months). Treatment (median, 6 weeks) consisted of immunotherapy and symptomatic therapy in 16 patients, immunotherapy alone for 2, and clonazepam alone for 1. Of these 19 patients, OMS remitted in 13 and improved in 3; 3 patients died (neurologic decline, 1; cancer, 1; and myocardial infarction, 1). The cause of death was of paraneoplastic origin in 60 of 116 literature review patients, with the most common carcinomas being lung (33 patients) and breast (7); the most common antibody was antineuronal nuclear antibody type 2 (anti-Ri, 15). Other causes were idiopathic in origin, 38 patients; parainfectious, 15 (human immunodeficiency virus, 7); toxic/metabolic, 2; and other autoimmune, 1. Both patients with N -methyl-D-aspartate receptor antibody had encephalopathy. Improvements were attributed to immunotherapy alone in 22 of 28 treated patients. CONCLUSIONS Adult-onset OMS is rare. Paraneoplastic and parainfectious causes (particularly human immunodeficiency virus) should be considered. Complete remission achieved with immunotherapy is the most common outcome.