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The main clinical features in patients with Duchenne muscular dystrophy (DMD) are (1) progressive muscle atrophy and weakness, (2) cardiac dysfunction, and (3) intellectual disability. However, there are few reports about natural history of patients with DMD develop renal dysfunction with age. Previous studies have shown that as skeletal muscle mass decreases, serum creatinine levels are less likely to reflect renal functions. In this study, we retrospectively examined how blood urea nitrogen (BUN) levels change over time. Patients clinically or genetically diagnosed with DMD were included in this study. The study period was from April 1st, 2012 to August 31st, 2023. The eligible patients underwent BUN levels' measurement at least twice. High BUN was defined as 30mg/dl or higher. Two or more consecutive increases in BUN are counted as one time. A total of 52 patients were included in the study, and their mean duration of observation was 7.7 years. Those with a BUN level ≤30 mg/dl obtained during the study period were considered to have renal dysfunction, accounting to 15 patients. High BUN was initially detected at 28.7 years of age (±8.0) and mean peak BUN level was 116.5 mg/dl. Their mean total duration of rising periods was 108 days, respectively. And these periods occurred 2.33 times/person on average. Two patients died from renal failure, according to the attending clinician. However, renal function improved in the remaining patients. No patients died of heart failure in the study period. The results for the remaining 37 patients showed that the mean age at the time of the first measurement was 14.8 years old (±6.1) and the mean observation period was 7.03 years. The average number of BUN tests was 20.5/7.03 y. (1 test /4.1month). The average maximum BUN value was 16.0 mg/dL (±5.6), the average minimum BUN value was 5.8 (±3.0), and the average value was 10.2. Although increase in BUN levels can be found in conditions other than renal dysfunction, BUN levels changed in 30% of patients with DMD. Since renal dysfunction is an inhibitory factor of treatment with morpholino-based drugs and affects survival, a future prospective study is required for elderly patients with DMD, renal function tests are recommended once every 3 to 4 months, and shorter follow-up is recommended if abnormalities are detected. 30% of patients with elderly DMD may have renal dysfunctions. About 10% in these patients may die by renal dysfunction, although in 90% of these patients' recovery can be expected within 3 months of natural course. [ABSTRACT FROM AUTHOR]

Background and Objectives: Becker muscular dystrophy (BMD) is an allelic disorder of Duchenne muscular dystrophy (DMD) in which pathogenic variants in DMD cause progressive worsening of motor dysfunction, muscle weakness and atrophy, and death due to respiratory and cardiac failure. BMD often has in-frame deletions that preserve the amino acid reading frame, but there are some cases with microvariants or duplications. In recent years, the importance of therapeutic development and care for BMD has been emphasized. Therefore, the purpose of this study was to understand the clinical characteristics of BMD patients with microvariants or duplications and to determine the genotype-phenotype relationship., Methods: The study focused on patients with pathogenic microvariants or duplications in DMD who were ambulatory after 16 years of age or had specific muscle biopsy results between June 13, 2017, and March 31, 2023. Informed consent was obtained from the patients or their surrogates. Data concerning DMD variants, muscle biopsy findings, skeletal muscle, respiratory and cardiac function, and CNS involvement were collected and analyzed statistically., Results: Thirty-three patients with BMD had pathogenic microvariants (missense variants, nonsense variants, splice site variants, and other microvariants), and 16 patients had in-frame duplications in DMD . Many patients with microvariants had abnormal ECG findings. The effect of variant type on patient outcomes varied. Regardless of the type of microvariant, skeletal muscle and respiratory dysfunction was more severe in mutants of the cysteine-rich/C-terminal domain than in rod domain mutants. On the other hand, there was no significant difference in the complication rate of CNS disorders among the 3 domains of dystrophin., Discussion: Microvariant forms, in particular, tend to vary in clinical severity according to the site of the dystrophin protein mutation rather than the type of pathogenic variant. The results of this study may be useful for genetic counseling, care, and treatment of patients with BMD., Competing Interests: The authors report no conflicts of interest regarding this study. Dr. Madoka Mori-Yoshimura is deceased; to the best of our knowledge, the relevant disclosures are none. Go to Neurology.org/NG for full disclosures., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. The etiology of sporadic ALS (sALS) has not yet been clarified. An increasing body of evidence suggests the involvement of viral infections and interferons (IFNs). Human myxovirus resistance protein A (MxA) is an IFN-induced dynamin-like GTPase that acts as a potent antiviral factor. This study examined MxA expression in ALS patient spinal cords using immunohistochemistry. Thirty-two cases of sALS (pathologically proven ALS-TDP), 10 non-ALS, other neurological disease control cases were examined. In most ALS cases, MxA cytoplasmic condensates were observed in the remaining spinal anterior horn neurons. The ALS group had a significantly higher rate of MxA-highly expressing neurons than the non-ALS group. Colocalization of MxA cytoplasmic condensate and transactive response DNA-binding protein 43 kDa (TDP-43)-positive inclusions was rarely observed. Because MxA has antiviral activity induced by IFNs, our results suggest that IFNs are involved in the pathogenesis of ALS in spinal cord anterior horn neurons. Our study also suggests that monitoring viral infections and IFN activation in patients with ALS may be critically important., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Association of Neuropathologists, Inc. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

FUS mutations are one of the major mutations in familial amyotrophic lateral sclerosis (ALS). The pathological hallmark is FUS-positive neuronal cytoplasmic inclusions (FUS-NCI), known as FUS proteinopathy. Human myxovirus resistance protein 1 (MxA) is an IFN-induced dynamin-like GTPase that acts as antiviral factor. In this study, we examined the expression of MxA in neurons bearing FUS-NCI. We performed immunohistochemistry for FUS and MxA to examine the expression of MxA in two autopsy cases with different FUS gene mutations localized at the nuclear localization signal site (Case 1, H517P; Case 2, R521C). MxA. Most neurons bearing FUS-NCI have increased cytoplasmic MxA expression. Increased cytoplasmic MxA showed several distribution patterns in relation to FUS-NCIs such as the following: colocalization with NCI, distribution more widely than NCI, and different distribution peaks from NCI. Our results suggested that antiviral signaling IFNs are involved upstream in the formation of FUS-NCI in ALS-FUS patients., (© 2023 The Authors. Brain Pathology published by John Wiley & Sons Ltd on behalf of International Society of Neuropathology.)

Objective: Becker muscular dystrophy (BMD) is a milder variant of Duchenne muscular dystrophy (DMD), a lethal X-linked muscular disorder. Here, we aim to investigat the clinical involvement of skeletal, respiratory, cardiac, and central nervous systems in patients with BMD, as well as genotype-phenotype relationships., Methods: This nationwide cohort study investigated the clinical manifestations and genotype-phenotype relationships in 225 patients with BMD having in-frame deletion from 22 medical centers. The primary outcome was to elucidate the association of genotype with skeletal muscle, respiratory, cardiac, and central nervous system disorders. Descriptive statistics were used to analyze the data., Results: The average age of the subjects was 31.5 (range, 1-81) years. Initial symptoms of BMD were muscular (60%), followed by asymptomatic hypercreatine kinasemia (32.4%) and central nervous system disorders (5.3%). Gait disturbance was observed in 53.8% of patients and the average age at wheelchair introduction was 36.5 years. The ventilator introduction rate was 6.7% at an average age of 36.6 years. More than 30% of patients had an abnormal electrocardiogram and approximately 15% had heart failure symptoms. Cardiac function on echocardiography varied significantly among the patients. The frequencies of seizures and intellectual/developmental disability were 8.0% and 16.9%, respectively. Exon 45-47deletion (del) was the most common (22.6%), followed by exon 45-48del (13.1%). Patients with exon 45-49del patients demonstrated severe skeletal muscle damage. Patients with exon 45-47del and exon 45-55del patients did not require ventilator use., Interpretation: The study provides important prognostic information for patients and clinicians to establish therapy plans and to implement preventative medicine., (© 2023 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Objective: To evaluate the swallowing function in the advanced stages of progressive supranuclear palsy (PSP) and clarify the factors that lead to adjustment of food consistency and discontinuation of oral intake., Methods: A total of 56 patients with PSP were recruited. Based on medical records, information about the basic attributes, clinical features (including axial rigidity and dementia), food intake, the results of a videofluoroscopic swallowing study (VFSS), and the timing of nasogastric tube transition and gastrostomy were extracted. From the VFSS images, the presence or absence of aspiration and retrocollis were assessed., Results: The average age at the onset, diagnosis, and the final follow-up examination were 67.6 ± 6.4 years, 71.6 ± 5.8 years, and 75.4 ± 5.6 years, respectively. The average duration of illness was 64.6 ± 42.8 months. Twenty-four individuals (42.9%) were continuing oral intake, while 32 were tube-fed, among whom 16 (50.0%) underwent gastrostomy tube placement. There were significant differences in the duration from the disease onset to tube feeding between the patients with and without cognitive decline at the time of the diagnosis ( p  < 0.01) and in the duration from the initial VFSS to tube feeding between the patients with and without aspiration on the initial VFSS ( p  < 0.01). There were significant differences in the duration from the diagnosis to tube feeding and from the initial VFSS to tube feeding between patients with and without axial rigidity at the time of the diagnosis ( p  < 0.05 and p  < 0.05, respectively). Additionally, there was a significant association between axial rigidity and retrocollis ( p  < 0.01)., Conclusion: Cognitive decline, axial rigidity and retrocollis, which are associated with the deterioration of dysphagia in PSP, are the highest risk factors for the discontinuation of oral intake. The early identification of these factors associated with the progression of dysphagia can contribute to the improvement of patient care and management., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Iwashita, Umemoto, Fujioka, Arahata, Dotsu, Oike and Tsuboi.)

Fused in sarcoma (FUS), coded by FUS, is a heterogeneous nuclear ribonucleoprotein (hnRNP). FUS mutations are among the major mutations in familial amyotrophic lateral sclerosis (ALS-FUS: ALS6). The pathological hallmarks of ALS-FUS are FUS-positive neuronal cytoplasmic inclusions (NCI). We examined various hnRNPs in FUS NCIs in the hippocampus in ALS-FUS cases with different FUS mutations (Case 1, H517P; Case 2, R521C). We also examined TDP43-positive NCIs in sporadic ALS hippocampi. Immunohistochemistry was performed using primary antibodies against FUS, p-TDP43, TDP43, hnRNPA1, hnRNPD, PCBP1, PCBP2, and p62. Numerous FUS inclusions were found in the hippocampal granule and pyramidal cell layers. Double immunofluorescence revealed colocalization of FUS and p-TDP43, and FUS and PCBP2 (p-TDP43/FUS: 64.3%, PCBP2/FUS: 23.9%). Colocalization of FUS and PCBP1, however, was rare (PCBP1/FUS: 7.6%). In the hippocampi of patients with sporadic ALS, no colocalization was observed between TDP43-positive inclusions and other hnRNPs. This is the first study to show that FUS inclusions colocalize with other hnRNPs, such as TDP43, PCBP2, and PCBP1. These findings suggest that in ALS-FUS, FUS inclusions are the initiators, followed by alterations of multiple other hnRNPs, resulting in impaired RNA metabolism., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Association of Neuropathologists, Inc. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Myotonic dystrophy type 1 (DM1) is an inherited autosomal-dominant condition that induces altered splicing of transcripts, including MAPT, leading to a distinctive abnormal deposition of tau protein in the CNS. We characterized the tau isoforms of abnormal depositions in the brains of 4 patients with classic DM1 by immunohistochemistry using isoform-specific antibodies. All patients, including those of presenile age, showed numerous neurofibrillary tangles (NFTs) of both 3-repeat and 4-repeat tau in the limbic area and mild involvement in the cerebral cortex. Amyloid-β deposition was only seen in 1 senile case while cortical tauopathy in all other cases was consistent with primary age-related tauopathy (PART). In the putamen and globus pallidus, only a few tau deposits were observed. Tau deposits in the brainstem frequently showed a DM1-specific pattern with 3-repeat tau dominant NFTs. Additionally, tau-positive astrocytes morphologically similar to tufted astrocytes and astrocytic plaques were occasionally observed in the brainstem; however, they were predominantly composed of 3-repeat tau. Thus, the classic DM1 showed both early onset of PART-like pathology in the limbic areas as a progeroid syndrome of DM1 and an abnormal splicing event in the brainstem leading to 3-repeat tau dominant accumulation with both neuronal and astrocytic involvement., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Association of Neuropathologists, Inc. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Aims: Oculopharyngodistal myopathy (OPDM) is caused by the expansion of CGG repeats in NOTCH2NLC (OPDM&#95;NOTCH2NLC) GIPC1 (OPDM&#95;GIPC1), or LRP12 (OPDM&#95;LRP12). Neuronal intranuclear inclusion disease (NIID) is clinically distinct from OPDM but is also caused by the expansion of CGG repeats in NOTCH2NLC, which may be an indicator of intranuclear inclusion in skin biopsy. We investigated the presence of intranuclear inclusions in skin biopsies from patients with OPDM and muscle diseases with a similar pathology to evaluate whether they will have similar diagnostic findings on skin biopsy., Methods: We analysed the frequency of p62-positive intranuclear inclusions in sweat gland cells, adipocytes and fibroblasts in skin biopsy samples from patients with OPDM (OPDM&#95;NOTCH2NLC [n = 2], OPDM&#95;GIPC1 [n = 6] and OPDM&#95;LRP12 [n = 3]), NIID (n = 1), OPMD (n = 1), IBM (n = 4) and GNE myopathy (n = 2)., Results: The p62-postive intranuclear inclusions were observed in all three cell types in both patients with OPDM&#95;NOTCH2NLC and a patient with NIID, in at least one cell type in all six patients with OPDM&#95;GIPC1, and all in three cell types in one of the three patients with OPDM&#95;LRP12. These findings were not observed in patients with OPMD, IBM or GNE myopathy., Conclusion: Intranuclear inclusions in skin biopsy samples are not specific to NIID and are found in all three types of genetically confirmed OPDM, suggesting that the underlying mechanism of OPDM may be similar to NIID, regardless of causative genes., (© 2021 British Neuropathological Society.)

To clarify the influence of coronavirus disease-19 (COVID-19) on the care of muscular dystrophy patients, we performed a questionnaire survey that was posted on the internet on May 11, 2020. By the end of July 2020, 542 responses had been collected. Approximately 30% of patients postponed regular consultations, and one-quarter of patients who received consultation more than once a month used telephone consultations. Two of 84 patients with Duchenne muscular dystrophy had reduced their steroid doses. A shortage of ventilator accessories and infection protection equipment occurred following the onset of COVID-19, and this shortage had a serious impact on medical care and infection prevention measures. Reductions in rehabilitation and other services, and avoidance of outings, led to a decrease in exercise and an increase in caregiver burden. Inpatients were restricted from going out and visiting family members. More than 20% of patients reported physical or mental complaints; however, few required treatment. COVID-19 has seriously affected the activities and quality of life of patients with muscular dystrophy. We will continue this survey and analyze the longitudinal changes., Competing Interests: Declaration of Competing Interest The authors report no conflicts of interest regarding this study., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Swallowing dysfunction is related to major cause of adverse events and an indicator of shorter survival among patients with neuromuscular disorders (NMD). It is critical to assess the swallowing function during disease progression, however, there are limited tools that can easily evaluate swallowing function without using videofluoroscopic or videoendoscopic examination. Here, we evaluated the longitudinal changes in tongue thickness (TT) and maximum tongue pressure (MTP) among patients with amyotrophic lateral sclerosis (ALS), myotonic dystrophy type 1 (DM1), and Duchenne muscular dystrophy (DMD)., Methods: Between 2010 and 2020, TT and MTP were measured from 21 ALS, 30 DM1, and 14 DMD patients (mean ages of 66.9, 44.5, and 21.4 years, respectively) at intervals of more than half a year. TT was measured, by ultrasonography, as the distance from the mylohyoid muscle raphe to the tongue dorsum, and MTP was determined by measuring the maximum compression on a small balloon when pressing the tongue against the palate. Then we examined the relationship between these evaluations and patient background and swallowing function., Results: Mean follow-up periods were 24.0 months in the ALS group, 47.2 months in the DM1group, and 61.1 months in the DMD group. The DMD group demonstrated larger first TT than the other groups, while the DM1 group had lower first MTP than the ALS group. The ALS group showed a greater average monthly reduction in mean TT than the DM1 group and greater monthly reductions in mean body weight (BW) and MTP than the other groups. Significant differences between the first and last BW, TT, and MTP measures were found only in the ALS group., Conclusions: This study suggests that ALS is associated with more rapid degeneration of tongue function over several years compared to DMD and DM1., (© 2021. The Author(s).)

Importance: Repeat expansion of CGG in LRP12 has been identified as the causative variation of oculopharyngodistal myopathy (OPDM). However, to our knowledge, the clinicopathologic features of OPDM with CGG repeat expansion in LRP12 (hereafter referred to as OPDM&#95;LRP12) remain unknown., Objective: To identify and characterize the clinicopathologic features of patients with OPDM&#95;LRP12., Design, Setting, and Participants: This case series included 208 patients with a clinical or clinicopathologic diagnosis of oculopharyngeal muscular dystrophy (OPDM) from January 1, 1978, to December 31, 2020. Patients with GCN repeat expansions in PABPN1 were excluded from the study. Repeat expansions of CGG in LRP12 were screened by repeat primed polymerase chain reaction and/or Southern blot., Main Outcomes and Measures: Clinical information, muscle imaging data obtained by either computed tomography or magnetic resonance imaging, and muscle pathologic characteristics., Results: Sixty-five Japanese patients with OPDM (40 men [62%]; mean [SD] age at onset, 41.0 [10.1] years) from 59 families with CGG repeat expansions in LRP12 were identified. This represents the most common OPDM subtype among all patients in Japan with genetically diagnosed OPDM. The expansions ranged from 85 to 289 repeats. A negative correlation was observed between the repeat size and the age at onset (r2 = 0.188, P = .001). The most common initial symptoms were ptosis and muscle weakness, present in 24 patients (37%). Limb muscle weakness was predominantly distal in 53 of 64 patients (83%), but 2 of 64 patients (3%) had predominantly proximal muscle weakness. Ptosis was observed in 62 of 64 patients (97%), and dysphagia or dysarthria was observed in 63 of 64 patients (98%). A total of 21 of 64 patients (33%) had asymmetric muscle weakness. Aspiration pneumonia was seen in 11 of 64 patients (17%), and 5 of 64 patients (8%) required mechanical ventilation. Seven of 64 patients (11%) developed cardiac abnormalities, and 5 of 64 patients (8%) developed neurologic abnormalities. Asymmetric muscle involvement was detected on computed tomography scans in 6 of 27 patients (22%) and on magnetic resonance imaging scans in 4 of 15 patients (27%), with the soleus and the medial head of the gastrocnemius being the worst affected. All 42 muscle biopsy samples showed rimmed vacuoles. Intranuclear tubulofilamentous inclusions were observed in only 1 of 5 patients., Conclusions and Relevance: This study suggests that OPDM&#95;LRP12 is the most frequent OPDM subtype in Japan and is characterized by oculopharyngeal weakness, distal myopathy that especially affects the soleus and gastrocnemius muscles, and rimmed vacuoles in muscle biopsy.

Introduction: Patients with neurological and neuromuscular disorders (NNMD) frequently experience swallowing disorders that increase aspiration pneumonia risk and therefore require specialized diets or tube feeding. Diet type level usually is assessed by video fluoroscopic swallowing study (VFSS). To identify a simpler assessment method, we examined the association between diet type (based on the Functional Oral Intake Scale [FOIS]) diet type and maximum tongue pressure (MTP)., Methods: From 2011-2020, FOIS diet type level and MTP were assessed in a sample of 927 patients. Of these patients, 186 had Parkinson's disease (PD), 69 had Parkinson-related disease (PRD), 61 had multiple system atrophy (MSA), 42 had spinocerebellar degeneration (SCD), 147 had amyotrophic lateral sclerosis (ALS), 180 had myotonic dystrophy type 1 (DM1), and 242 had Duchenne muscular dystrophy (DMD). VFSS was conducted while patients swallowed water and foods containing barium. MTP measurements were collected the same day. Participants' diet type level was adjusted based on the VFSS, with some participants requiring multiple examinations. Relationships between diet type level and MTP were tested using univariate and Spearman rank correlation analyses., Results: Mean MTP for the entire NNMD group (25.5 ± 13.1 kPa) was lower than that of healthy elderly individuals, as determined in previous reports. The highest MTP was found in the MSA group (32.2 ± 15.7 kPa) and the lowest in the DM1 group (19.1 ± 9.0 kPa). Diet type level was highest in the MSA group (5.8 ± 1.4) and lowest in the DMD group (5.2 ± 1.7). A significant correlation was observed between diet type level and MTP (R = 0.384, p < 0.001). The optimum MTP cutoff values-detected using ROC curves to predict a requirement to change to a dysphagia diet-was highest in the DMD group (29.0 kPa) and lowest in the ALS group (12.3 kPa)., Conclusions: The decision to change NNMD patients to a dysphagia diet can be made based on MTP. Modifying a patient's oral diet (FOIS level ≤ 5) should be considered for those with a MTP of 10-25 kPa, with the cutoff value varying by disease., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background and Objective: The delayed-on phenomenon (DOP) related to levodopa treatment frequently disturbs quality of life in advanced-stage Parkinson's disease (PD) patients. The objective of this study was to explore the impact of swallowing dysfunction on the development of DOP., Methods: Swallowing function was investigated by endoscopic evaluation in 11 PD patients with the DOP and 9 PD patients without the DOP during the on phase. Residual drug in the pharynx after taking the drug in tablet, capsule, and powder forms was also observed., Results: Residual drug was seen in the pharynx in six cases (30.0%). Pooling of saliva, delayed swallowing reflex, and residual drug were more frequent in the DOP group than in the group without the DOP ( P  < 0.05). The odds ratios for residual drug in the pharynx, pooling of saliva, and delayed swallowing reflex for the DOP were 42.7 (95% confidence interval, 1.89-962.9), 14.0 (95% confidence interval, 1.25-156.6), and 15.8 (95% confidence interval, 1.75-141.4), respectively., Conclusions: These results suggest that swallowing dysfunction leading to residual antiparkinsonian drug in the pharynx has substantial impacts on the DOP in PD patients., Competing Interests: This study was funded by JSPS KAKENHI Grants 15K19501 and 17K12069. The authors have no conflict of interest to declare., (© 2020 International Parkinson and Movement Disorder Society.)

Background: Tongue and pharyngeal pressure is an essential factor associated with the swallowing function; however, little is known about the difference in tongue and pharyngeal pressure between neuromuscular diseases. This study aimed to characterize tongue and pharyngeal pressure in myotonic dystrophy type 1 (DM1), Duchenne muscular dystrophy (DMD), and amyotrophic lateral sclerosis (ALS) patients., Methods: This study recruited 17 DMD patients, 32 DM1 patients, and 26 ALS patients. They underwent separate measurements of tongue and pharyngeal pressure under videofluoroscopy, swallowing 5 mL of barium water. We measured the largest change in pharyngeal pressure in the hypopharynx and the upper esophageal sphincter (UES) over several swallows., Results: The mean tongue pressure (TP) was greatest in the DMD group than in the other groups ( p <0.01). There was a significant difference in pressure changes in the hypopharynx and UES between the DM1 group and other groups ( p <0.01). Significant correlations were observed between pressure change in the UES and the patient's age in the DMD group ( R =-0.500, p =0.045) and between pressure change in the hypopharynx and TP in the DM1 group ( R =0.421, p =0.016). There was a significant correlation between pressure change in the hypopharynx and disease severity in the ALS group ( R =0.435, p =0.030)., Conclusion: Patients with DMD, DM1, and ALS have weakness in the muscles involved in swallowing; however, the results of this study suggested that each disorder has a distinctive profile of impairment in the swallowing function., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Objective: In Duchenne muscular dystrophy (DMD) patients cardiac abnormalities are often detected. In adult DMD patients cardiac disease (CD) is a cause of death which increases by age and is related to respiratory dysfunction. Studies have demonstrated that CD in early DMD can be detected by echocardiography (EC) or semi-quantitative gated single photon emission tomography ((201)Tl SQGS), and the accuracy of these two tests is similar. As the disease advances, evaluation of CD by EC becomes difficult due to thoracic deformity and scoliosis. We compared (201)Tl SQGS and EC in the evaluation of cardiac function in late stage DMD, based on the ejection fraction (EF) value calculated by both tests. Twenty-three males with late stage DMD, 12 to 35 years of age (22.2±7.5), were studied by (201)Tl SQGS and EC. The mean EF value by (201)Tl SQGS was 60.8%±14.1%, which differed from that obtained by EC (52.7%±9.8%, P=0.003). Eleven patients less than 20 years old did not demonstrate a significant difference between the two tests (P=0.06), however, 12 patients over 20 years of age had significantly different results between tests (P=0.002)., Conclusion: Although our patients were few we indicated that in DMD patients, aged older than 20 years, at an advanced stage of the disease, the EF values calculated by EC were lower than those by (201)Tl SQGS possibly due to thoracic deformity.

Objective: The diagnosis of mitochondrial disorders (MDs) is occasionally difficult because patients often present with solitary, or a combination of, symptoms caused by each organ insufficiency, which may be the result of respiratory chain enzyme deficiency. Growth differentiation factor 15 (GDF-15) has been reported to be elevated in serum of patients with MDs. In this study, we investigated whether GDF-15 is a more useful biomarker for MDs than several conventional biomarkers., Methods: We measured the serum levels of GDF-15 and fibroblast growth factor 21 (FGF-21), as well as other biomarkers, in 48 MD patients and in 146 healthy controls in Japan. GDF-15 and FGF-21 concentrations were measured by enzyme-linked immunosorbant assay and compared with lactate, pyruvate, creatine kinase, and the lactate-to-pyruvate ratio. We calculated sensitivity and specificity and also evaluated the correlation based on two rating scales, including the Newcastle Mitochondrial Disease Rating Scale (NMDAS)., Results: Mean GDF-15 concentration was 6-fold higher in MD patients compared to healthy controls (2,711 ± 2,459 pg/ml vs 462.5 ± 141.0 pg/mL; p < 0.001). Using a receiver operating characteristic curve, the area under the curve was significantly higher for GDF-15 than FGF-21 and other conventional biomarkers. Our date suggest that GDF-15 is the most useful biomarker for MDs of the biomarkers examined, and it is associated with MD severity., Interpretation: Our results suggest that measurement of GDF-15 is the most useful first-line test to indicate the patients who have the mitochondrial respiratory chain deficiency., (© 2015 The Authors Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)