Physical and Mental Aspects of Quality of Life in Patients With Charcot-Marie-Tooth Disease Type 1A

Introduction

Charcot-Marie-Tooth type 1A (CMT1A) comprises ~50% of all CMT cases. CMT1A is a slowly progressive motor and sensory neuropathy that leads to significant disability. We aimed to investigate the quality of life (QoL) in Serbian patients with CMT1A and to assess sociodemographic and clinical features associated with their QoL.

Material and Methods

Forty-five genetically confirmed patients with CMT1A were included −60% women [age 50.4 ± 12.6 years, disease duration 22 (12.5–31.5) years]. SF-36, Medical Research Council (MRC) Sum Score, CMT Examination Score (CMTES), Overall Neuropathy Limitation Scale (ONLS), Beck Depression Inventory (BDI), and Krupp's Fatigue Severity Scale (FSS) were used in the study.

Results

Regarding SF-36, Mental Health and Social Functioning were the scales with the best achievements, whereas Role Physical was the worst domain. Worse QoL in patients with CMT1A was associated with elder age (rho = −0.34, p < 0.05), longer disease duration (rho = −0.31, p < 0.05), more pronounced muscle weakness measured by MRC-SS (rho = 0.43, p < 0.01), presence of tremor (p < 0.05), worse CMTES (rho = −0.68, p < 0.01), more severe disability in upper (rho = −0.70, p < 0.01) and lower limbs (rho = −0.61, p < 0.01) measured by ONLS scores, use of walking aids (p < 0.01), and with depression (p < 0.01) and fatigue (p < 0.01). Worse scores on CMTES (beta = −0.43, p < 0.01), BDI (beta = −0.39, p < 0.01), and FSS (beta = −0.36, p < 0.01) were significant independent predictors of worse QoL in patients with CMT1A (adjusted R² = 0.77, p < 0.001).

Conclusion

Besides impairment made directly by CMT1A itself, QoL in these patients was also strongly affected by the presence of depression and fatigue. Since CMT1A is still not a curable disease, it is of interest to identify factors associated with QoL that are amenable to treatment.

Identification of GAA variants through whole exome sequencing targeted to a cohort of 606 patients with unexplained limb-girdle muscle weakness

Background

Late-onset Pompe disease is a rare genetic neuromuscular disorder caused by a primary deficiency of α-glucosidase and the associated accumulation of glycogen in lysosomal vacuoles. The deficiency of α-glucosidase can often be detected using an inexpensive and readily accessible dried blood spot test when Pompe disease is suspected. Like several neuromuscular disorders, Pompe disease typically presents with progressive weakness of limb-girdle muscles and respiratory insufficiency. Due to the phenotypic heterogeneity of these disorders, however, it is often difficult for clinicians to reach a diagnosis for patients with Pompe disease. Six hundred and six patients from a European population were recruited onto our study. Inclusion criteria stipulated that index cases must present with limb-girdle weakness or elevated serum creatine kinase activity. Whole exome sequencing with at least 250 ng DNA was completed using an Illumina exome capture and a 38 Mb baited target. A panel of 169 candidate genes for limb-girdle weakness was analysed for disease-causing variants.

Results

A total of 35 variants within GAA were detected. Ten distinct variants in eight unrelated index cases (and four siblings not sequenced in our study) were considered disease-causing, with the patients presenting with heterogeneous phenotypes. The eight unrelated individuals were compound heterozygotes for two variants. Six patients carried the intronic splice site c.-13 T > G transversion and two of the six patients also carried the exonic p.Glu176ArgfsTer45 frameshift. Four of the ten variants were novel in their association with Pompe disease.

Conclusions

Here, we highlight the advantage of using whole exome sequencing as a tool for detecting, diagnosing and treating patients with rare, clinically variable genetic disorders.

Routine echocardiography in patients with myotonic dystrophy type 1

BACKGROUND

Myotonic dystrophy type 1 (DM1) is an autosomal-dominant disease. One third of DM1 patients die suddenly, most of them due to the heart conduction abnormalities and arrhythmias. The aim of this study was to analyze echocardiographic findings in a large cohort of DM1 patients.

METHODS

This retrospective study comprised 111 patients and 71 healthy controls (HCs) matched for gender and age.

RESULTS

Mitral valve (MV) prolapse was observed in 23% of our DM1 patients vs. 8.5% of HCs (p < 0.05). Left ventricle (LV) systolic dysfunction was observed in 6% of patients and none of the HCs (p < 0.05). Frequency of diastolic dysfunction showed no significant difference between DM1 patients and HCs (8.1% vs. 15.5%, p > 0.05). Systolic dysfunction was more common in patients with severe electrocardiographic (ECG) abnormality (18.8% vs. 2.7%, p < 0.01).

CONCLUSION

One fourth of DM1 patients have MV prolapse. Approximately 15% of DM1 patients have systolic or diastolic LV dysfunction. These patients should have benefit from medical therapy. Furthermore, it seems that treatment of conduction defects might prevent development of the heart failure (HF).

Myopathic changes detected by quantitative electromyography in patients with MuSK and AChR positive myasthenia gravis

Myopathic changes are frequent a electrophysiological finding in patients with muscle specific tyrosine kinase (MuSK) positive myasthenia gravis (MG). The aim of this study was to explore the importance of quantitative electromyography (EMG) in the detection of myopathic changes in MuSK MG patients. Classical and quantitative EMG were performed in 31 MuSK and 28 acetylcholine receptor (AChR) positive MG patients, matched by sex, age, disease duration and severity. Classical EMG revealed the presence of myopathic changes more frequently in MuSK MG compared to AChR MG patients, especially in the facial muscles. Quantitative EMG registered myopathic lesions more frequently than classical EMG, but the frequency was similar between MuSK and AChR MG patients. Quantitative EMG revealed myopathic changes in the majority of both MuSK and AChR positive MG patients. This examination is sensitive, but it cannot be used to differentiate between MG patients belonging to the different disease groups. It should not be used in isolation. Rather, it should complement classical EMG in the detection of myopathic changes.

Transcranial sonography in patients with myotonic dystrophy type 1

INTRODUCTION

In this study we analyzed transcranial sonography (TCS) in patients with myotonic dystrophy type 1 (DM1).

METHODS

This cross-sectional study included 66 DM1 patients and 55 matched healthy controls (HCs). Echogenicity of the brainstem raphe (BR) and substantia nigra (SN) and third ventricle width (DTV) were assessed by TCS.

RESULTS

BR hypoechogenicity was more common in DM1 patients than in HCs (37.7% vs. 7.8%, P < 0.01). Patients with depression or fatigue were more likely to have BR hypoechogenicity (80.0% vs. 29.4%, P < 0.01 and 51.9% vs. 24.2%, P < 0.05, respectively). Both hypoechogenicity and hyperechogenicity of SN were more frequent in DM1 patients than in controls (26.2% vs. 10.9% and 13.1% vs. 1.8%, respectively, P < 0.01). DTV was increased in DM1 patients compared with HCs (6.0 ± 1.4 vs. 4.9 ± 0.9 mm, P < 0.01).

CONCLUSION

TCS can offer new insight into structural changes of several cerebral areas in patients with DM1.

The coexistence of myasthenia gravis and myotonic dystrophy type 2 in a single patient

Background

Myasthenia gravis (MG) and myotonic dystrophy type 2 (DM2) are rare disorders individually, and their coexistence in the same patient is very rare. We present a patient in which these two diseases coexisted.

Case Report

The patient complained of diplopia, fluctuating limb weakness, and difficulties in swallowing and speaking. A neurological examination revealed diplopia, facial, weakness of the neck and proximal limb muscles, dysphagia, dysphonia, and myotonia. The patient's mother had DM2 and her maternal grandfather had cataracts. MG was confirmed in our patient by positive results for neostigmine and a repetitive nerve stimulation test, and elevated serum anti-acetylcholine-receptor antibodies, while DM2 was confirmed by electromyography and genetic testing. The patient improved remarkably after treatment with anticholinesterases, corticosteroids, and azathioprine.

Conclusions

This is the second reported case of the coexistence of DM2 and MG in the same patient. Since the symptoms of these two diseases overlap it is very important to keep in mind the possibility of their coexistence, so that MG is not overlooked in patients with a family history of myotonic dystrophy.

Is hyperlipidemia correlated with longer survival in patients with amyotrophic lateral sclerosis?

Amyotrophic lateral sclerosis (ALS) is the most serious form of degenerative motor neuron disease in adults, whose relentless course leads to death within 2-5 years, generally due to respiratory failure. Apart from the age and site of onset, no other factors have consistently demonstrated to be related to the ALS outcome. The aim of the study was to investigate the influence of fasting serum lipid levels (cholesterol and triglycerides) and the body mass index (BMI) at the time of diagnosis on survival in ALS patients. The study included 82 patients with ALS residing in the Belgrade area who were diagnosed with ALS over a time period of 4 years (2006-2009). Survival was assessed by the Kaplan-Meier method. In this retrospective study, 39 (47.56%) patients had normal values of lipids and 43 (52.43%) patients had hyperlipidemia. The mean survival time from the onset of symptoms for patients with normal lipidemia was 4.21 ± 0.5 years, while the mean survival time from the onset of symptoms for patients with hyperlipidemia was 5.0 ± 0.67 years (P = 0.36). We also did not register a significant difference in survival in relation to gender, the site or age of onset, even though we noticed a longer survival in patients with hyperlipidemia in all of the examined groups, especially in the group of younger patients, with the onset of the disease before the age of 45 years. If we take into account the fact that BMI is pathophysiologically associated with cholesterol and triglyceride serum levels, the results in our study complement each other showing that patients with a higher BMI, registered in 28.8% of the cases, do not live longer. Our findings show that hyperlipidemia, which we found in 52.43% of our ALS patients, at the time of diagnosis, is not related to significantly longer survival.