Transcranial brain parenchyma sonographic findings in patients with myotonic dystrophy type 1 and 2.

Introduction: Myotonic dystrophy type 1 (DM1) and 2 (DM2) are genetically determined progressive muscular disorders with multisystemic affection, including brain involvement. Transcranial sonography (TCS) is a reliable diagnostic tool for the investigation of deep brain structures. We sought to evaluate TCS findings in genetically confirmed DM1 and DM2 patients, and further correlate these results with patients' clinical features. Methods: This cross-sectional study included 163 patients (102 DM1, 61 DM2). Echogenicity of the brainstem raphe (BR) and substantia nigra (SN) as well as the diameter of the third ventricle (DTV) were assessed by TCS. Patients were evaluated using the Hamilton Depression Rating Scale, Fatigue Severity Scale and Daytime Sleepiness Scale. Results: SN hyperechogenicity was observed in 40% of DM1 and 34% of DM2 patients. SN hypoechogenicity was detected in 17% of DM1 and 7% of DM2 patients. BR hypoechogenicity was found in 36% of DM1 and 47% of DM2 subjects. Enlarged DTV was noted in 19% of DM1 and 15% of DM2 patients. Older, weaker, depressive, and fatigued DM1 patients were more likely to have BR hypoechogenicity (p < 0.05). DTV correlated with age and disease duration in DM1 (p < 0.01). In DM2 patients SN hyperechogenicity correlated with fatigue. Excessive daytime sleepiness was associated with hypoechogenic BR (p < 0.05) and enlarged DVT (p < 0.01) in DM2 patients. Conclusions: TCS is an easy applicable and sensitive neuroimaging technique that could offer new information regarding several brainstem structures in DM1 and DM2. This may lead to better understanding of the pathogenesis of the brain involvement in DM with possible clinical implications.

Myotonic dystrophy type 1 in the COVID-19 era.

INTRODUCTION: Myotonic dystrophy type 1 (DM1) is the most prevalent muscular dystrophy in adults. People with DM1 might represent a high-risk population for respiratory infections, including COVID-19. Our aim was to evaluate the characteristics of COVID-19 infection and vaccination rate in DM1 patients. METHODS: This cross-sectional cohort study included 89 patients from the Serbian registry for myotonic dystrophies. Mean age at testing was 48.4 ± 10.4 years with 41 (46.1%) male patients. Mean duration of the disease was 24.0 ± 10.3 years. RESULTS: COVID-19 infection was reported by 36 (40.4%) DM1 patients. Around 14% of patients had a more severe form of COVID-19 requiring hospitalization. The severity of COVID-19 was in accordance with the duration of DM1. A severe form of COVID-19 was reported in 20.8% of patients who were not vaccinated against SARS-CoV-2 and in none of the vaccinated ones. The majority of 89 tested patients (66.3%) were vaccinated against SARS-CoV-2. About half of them (54.2%) received three doses and 35.6% two doses of vaccine. Mild adverse events after vaccination were recorded in 20.3% of patients. CONCLUSIONS: The percentage of DM1 patients who suffered from COVID-19 was like in general population, but with more severe forms in DM1, especially in patients with longer DM1 duration. The study indicated an overall favorable safety profile of COVID-19 vaccines among individuals with DM1 and its ability to protect them from severe COVID-19.

Clinical score for early diagnosis of myotonic dystrophy type 2.

INTRODUCTION: Myotonic dystrophy type 2 (DM2) is a rare, multisystemic, autosomal dominant disease with highly variable clinical presentation. DM2 is considered to be highly underdiagnosed. OBJECTIVE: The aim of this study was to determine which symptoms, signs, and diagnostic findings in patients referred to neurological outpatient units are the most indicative to arouse suspicion of DM2. We tried to make a useful and easy-to-administer clinical scoring system for early diagnosis of DM2-DM2 early diagnosis score (DM2-EDS). PATIENTS AND METHODS: Two hundred ninety-one patients with a clinical suspicion of DM2 were included: 69 were genetically confirmed to have DM2, and 222 patients were DM2 negative. Relevant history, neurological, and paraclinical data were obtained from the electronic medical records. RESULTS: The following parameters appeared as significant predictors of DM2 diagnosis: cataracts (beta = 0.410, p < 0.001), myotonia on needle EMG (beta = 0.298, p < 0.001), hand tremor (beta = 0.211, p = 0.001), positive family history (beta = 0.171, p = 0.012), and calf hypertrophy (beta = 0.120, p = 0.043). In the final DM2-EDS, based on the beta values, symptoms were associated with the following values: cataracts (present 3.4, absent 0), myotonia (present 2.5, absent 0), tremor (present 1.7, absent 0), family history (positive 1.4, negative 0), and calf hypertrophy (present 1.0, absent 0). A cut-off value on DM2-EDS of 3.25 of maximum 10 points had a sensitivity of 84% and specificity of 81% to diagnose DM2. CONCLUSION: Significant predictors of DM2 diagnosis in the neurology outpatient unit were identified. We made an easy-to-administer DM2-EDS score for early diagnosis of DM2.

Autoimmune Diseases in Patients With Myotonic Dystrophy Type 2.

Introduction: Myotonic dystrophy type 2 (DM2) is a rare autosomal dominant multisystemic disease with highly variable clinical presentation. Several case reports and one cohort study suggested a significant association between DM2 and autoimmune diseases (AIDs). Aim: The aim of this study is to analyze the frequency and type of AIDs in patients with DM2 from the Serbian DM registry. Patients and Methods: A total of 131 patients with DM2 from 108 families were included, [62.6% women, mean age at DM2 onset 40.4 (with standard deviation 13) years, age at entering the registry 52 (12.8) years, and age at analysis 58.4 (12.8) years]. Data were obtained from Akhenaten, the Serbian registry for DM, and through the hospital electronic data system. Results: Upon entering the registry, 35 (26.7%) of the 131 patients with DM2 had AIDs including Hashimoto thyroiditis (18.1%), rheumatoid arthritis, diabetes mellitus type 1, systemic lupus, Sjogren's disease, localized scleroderma, psoriasis, celiac disease, Graves's disease, neuromyelitis optica, myasthenia gravis, and Guillain-Barre syndrome. At the time of data analysis, one additional patient developed new AIDs, so eventually, 36 (28.8%) of 125 DM2 survivors had AIDs. Antinuclear antibodies (ANAs) were found in 14 (10.7%) of 63 tested patients, including 12 without defined corresponding AID (all in low titers, 1:40 to 1:160). Antineutrophil cytoplasmic antibodies (ANCAs) were negative in all 50 tested cases. The percentage of women was significantly higher among patients with AIDs (82.9% vs. 55.2%, p <0.01). Conclusion: AIDs were present in as high as 30% of the patients with DM2. Thus, screening for AIDs in DM2 seems reasonable. Presence of AIDs and/or ANAs may lead to under-diagnosis of DM2.

Cognitive assessment in patients with myotonic dystrophy type 2.

Myotonic dystrophy type 2 (DM2) is an autosomal dominant multisystemic disorder. Previous studies conducted on small cohorts of DM2 patients indicated presence of a cognitive dysfunction. We aimed to assess cognitive functions in a larger cohort of Serbian DM2 patients using an extensive battery of neuropsychological tests. The study included 76 patients with a genetically confirmed DM2, 68 of whom had all tests for different cognitive domains performed. Patients underwent clinical and neuropsychological testing, including cognitive screening and assessment of general intellectual level, attention, executive and visuospatial abilities, memory, and language functions. Only 6% of patients achieved a below-average score on the general intellectual level test. Cognitive screening tests indicated presence of cognitive deficits in 5.5% of patients according to the Mini Mental State Examination test and 25.8% according to the Addenbrooke's Cognitive Examination Revised test. Twenty-four (35.3%) patients had a cognitive impairment (being two standard deviations out of norm in at least two cognitive domains). Around one quarter of DM2 patients had a significant cognitive impairment that interfered with their everyday functioning. Patients with significant cognitive impairment were older at testing and at disease onset, less educated, and had more severe muscle weakness.

Employment status of patients with Charcot-Marie-Tooth type 1A.

Previous studies showed that being unemployed is associated with lower quality of life in patients with Charcot-Marie-Tooth type 1A (CMT1A). The aim of this study was to assess the differences between CMT1A patients capable of working and CMT1A patients incapable of working due to CMT1A. Forty-four patients with genetically confirmed CMT1A were included. Medical Research Council (MRC) Sum Score, Charcot-Marie-Tooth Neuropathy Score (CMTNS), CMT Examination Score (CMTES), Overall Neuropathy Limitations Scale (ONLS), Beck Depression Inventory (BDI), Krupp's Fatigue Severity Scale (FSS), and Falls Efficacy Score (FES) were used. Whole cohort was divided into two groups: 1. CMT1A patients capable of working (employed and unemployed not due to CMT) and 2. CMT1A patients incapable of working due to CMT1A (unemployed due to CMT and retired due to CMT). At time of testing, 38.6% patients were employed, 13.6% were unemployed due to CMT, 6.8% were unemployed but not due to CMT, and 40.9% were retired early due to disability caused by CMT. Patients retired due to CMT1A at the age of 43 ± 10 years. ONLS total score and physical work appeared as significant independent predictors of being incapable of working due to CMT1A. Patients incapable of working were almost four times more likely to have fatigue (OR = 3.7, 95% CI 1.0-13.1, p < 0.05) and 11 times more likely to have fear of falling (OR = 11.0, 95% CI 2.0-59.7, p < 0.01). Patients with more severe functional disability and physical type of job were most likely incapable of working due to CMT1A. Incapability of working was associated with fatigue and fear of falling.

Cerebral involvement and related aspects in myotonic dystrophy type 2.

Myotonic dystrophy type 2 (DM2) is an autosomal dominant multisystemic disorder caused by CCTG repeats expansion in the first intron of the CNBP gene. In this review we focus on the brain involvement in DM2, including its pathogenic mechanisms, microstructural, macrostructural and functional brain changes, as well as the effects of all these impairments on patients' everyday life. We also try to understand how brain abnormalities in DM2 should be adequately measured and potentially treated. The most important pathogenetic mechanisms in DM2 are RNA gain-of-function and repeat-associated non-ATG (RAN) translation. One of the main neuroimaging findings in DM2 is the presence of diffuse periventricular white matter hyperintensity lesions (WMHLs). Brain atrophy has been described in DM2 patients, but it is not clear if it is mostly caused by a decrease of the white or gray matter volume. The most commonly reported specific cognitive symptoms in DM2 are dysexecutive syndrome, visuospatial and memory impairments. Fatigue, sleep-related disorders and pain are also frequent in DM2. The majority of key symptoms and signs in DM2 has a great influence on patients' daily lives, their psychological status, economic situation and quality of life.

Molecular and Clinical Implications of Variant Repeats in Myotonic Dystrophy Type 1.

Myotonic dystrophy type 1 (DM1) is one of the most variable monogenic diseases at phenotypic, genetic, and epigenetic level. The disease is multi-systemic with the age at onset ranging from birth to late age. The underlying mutation is an unstable expansion of CTG repeats in the DMPK gene, varying in size from 50 to >1000 repeats. Generally, large expansions are associated with an earlier age at onset. Additionally, the most severe, congenital DM1 form is typically associated with local DNA methylation. Genetic variability of DM1 mutation is further increased by its structural variations due to presence of other repeats (e.g., CCG, CTC, CAG). These variant repeats or repeat interruptions seem to confer an additional level of epigenetic variability since local DNA methylation is frequently associated with variant CCG repeats independently of the expansion size. The effect of repeat interruptions on DM1 molecular pathogenesis is not investigated enough. Studies on patients indicate their stabilizing effect on DMPK expansions because no congenital cases were described in patients with repeat interruptions, and the age at onset is frequently later than expected. Here, we review the clinical relevance of repeat interruptions in DM1 and genetic and epigenetic characteristics of interrupted DMPK expansions based on patient studies.

Quality of life in hereditary neuropathy with liability to pressure palsies is as impaired as in Charcot-Marie-Tooth disease type 1A.

To date, only one study assessed quality of life (QoL) in patients with hereditary neuropathy with liability to pressure palsies (HNPP). We aimed to fill in this gap by investigating QoL in a cohort of patients with HNPP compared to Charcot-Marie-Tooth type 1A (CMT1A) patients, as well as to analyze sociodemographic and clinical features associated with QoL in HNPP. Eighteen genetically confirmed HNPP patients were age-and gender-matched with 18 CMT1A patients. SF-36 questionnaire was used to assess QoL. Medical Research Council (MRC) Sum Score, CMT Neuropathy Score (CMTNS), Overall Neuropathy Limitation Scale Score (ONLS), Falls Efficacy Score (FES), Visual Analog Pain Scale, Beck Depression Inventory (BDI) and Fatigue Severity Scale (FSS) were also used in our study. Although HNPP patients were less clinically impaired, no difference was observed in these two cohorts regarding SF-36 scores. Worse QoL in HNPP patients was associated with lower education (p < 0.01), physical work (p < 0.05), higher number of clinically affected nerves during the disease course (p < 0.01), worse MRC-SS score (p < 0.01), worse ONLS score (p < 0.01), and with more severe pain (p < 0.01), depression (p < 0.01), and fatigue (p < 0.01). Worse pain at the moment of testing appeared as a significant independent predictor of worse QoL in HNPP patients (ß = - 0.93, p < 0.001). QoL was similarly impaired in patients with HNPP and patients with CMT1A. We identified different factors associated with QoL in HNPP, and many of these factors are amenable to treatment which is of special interest in these still incurable disease.

Yield of the PMP22 deletion analysis in patients with compression neuropathies.

INTRODUCTION: Hereditary neuropathy with liability to pressure palsies (HNPP) is a rare neuromuscular disorder, mostly caused by PMP22 deletion. AIM: To determine a yield of the genetic analysis of PMP22 gene deletion in patients with compression neuropathies. METHOD: We included 112 patients with clinical suspicion of HNPP diagnosis. Nerve conduction studies (NCS) were performed for motor and sensory nerves bilaterally. Number of the PMP22 gene copies was determined using a real-time polymerase chain reaction (RT-PCR). RESULTS: PMP22 deletion was found in 34 (30.3%) patients. Patients with genetically confirmed HNPP had 12 years earlier disease onset compared to other patients with compression neuropathies (p < 0.01), more nerves affected during lifespan (5.5 ± 3.5 vs. 3.0 ± 2.0, p < 0.01) and at the time of referral (2.7 ± 2.5 vs. 2.0 ± 1.9, p < 0.05). HNPP patients had positive family history more frequently (p < 0.01). Foot deformities (pes cavus and hammertoe), symmetric muscle atrophy in lower legs and absent muscle reflexes in lower limbs were more common in HNPP patients. NCS abnormalities were also more common in HNPP group. Multiple linear regression analysis identified positive family history (ß = + 0.35, p < 0.01) and decreased sensory conduction velocity in at least three sensory nerves (ß = + 0.40, p < 0.01) as independent predictors of the PMP22 deletion. CONCLUSION: Among patients with compression neuropathies, those with a positive family history, earlier symptom onset and NCS abnormalities had a higher chance to have PMP22 deletion.

Neuropathic pain in patients with Charcot-Marie-Tooth type 1A.

BACKGROUND: Only several studies analyzed the characteristics of neuropathic pain (NeP) more extensively in patients with Charcot-Marie-Tooth type 1A (CMT1A). Therefore, we sought to determine the frequency and features of NeP in CMT1A patients and to assess the association between NeP and sociodemographic and clinical characteristics of patients with CMT1A. METHODS: Our research included 51 genetically diagnosed CMT1A patients. The International Association for the Study of Pain (IASP) criteria were used for diagnosis of NeP. PainDETECT questionnaire (PD-Q) was used to assess NeP features. The Medical Research Council (MRC) Sum Score, CMT Neuropathy Score (CMTNS), Overall Neuropathy Limitation Scale (ONLS) score, and Beck Depression Inventory were also used. RESULTS: NeP was present in 15 (29.4%) patients with CMT1A. The average intensity of pain was 5.7 ± 2.2 out of 10. The most sensitive neuropathic symptoms were numbness, then tingling, and burning sensations, while the most specific symptom was allodynia. Patients with NeP more frequently reported pain in the back (p < 0.01) and the trunk (p < 0.05). Patients with NeP had more pronounced disability of the upper extremities and overall disability, as assessed by the ONLS score (p < 0.05). Depression was more frequent in patients with NeP compared with patients without NeP (66.7 to 13.9%, p < 0.01). CONCLUSION: NeP was present in almost one-third of the patients with CMT1A and it was moderate on average. Presence of NeP was associated with worse functional disability and depression.

Phenotypic and genetic spectrum of patients with limb-girdle muscular dystrophy type 2A from Serbia.

Limb-girdle muscular dystrophy (LGMD) type 2A (calpainopathy) is an autosomal recessive disease caused by mutation in the CAPN3 gene. The aim of this study was to examine genetic and phenotypic features of Serbian patients with calpainopathy. The study comprised 19 patients with genetically confirmed calpainopathy diagnosed at the Neurology Clinic, Clinical Center of Serbia and the Clinic for Neurology and Psychiatry for Children and Youth in Belgrade, Serbia during a ten-year period. Eighteen patients in this cohort had c.550delA mutation, with nine of them being homozygous. In majority of the patients, disease started in childhood or early adulthood. The disease affected shoulder girdle - upper arm and pelvic girdle - thigh muscles with similar frequency, with muscles of lower extremities being more severely impaired. Facial and bulbar muscles were spared. All patients in this cohort, except two, remained ambulant. None of the patients had cardiomyopathy, while 21% showed mild conduction defects. Respiratory function was mildly impaired in 21% of patients. Standard muscle histopathology showed myopathic and dystrophic pattern. In conclusion, the majority of Serbian LGMD2A patients have the same mutation and similar phenotype.

Correction to: Eight years after an international workshop on myotonic dystrophy patient registries: case study of a global collaboration for a rare disease.

The original version of this article [1] unfortunately included an error to an author's name. Author Jordi Díaz-Manera was erroneously presented as Jorge Alberto Diaz Manera. The correct author name has been included in the author list of this Correction article.

Quality of life in patients with multifocal motor neuropathy from Serbia.

INTRODUCTION AND AIM: Multifocal motor neuropathy (MMN) is a rare, chronic disorder with potentially severe and progressive disability, which may affect patients' quality of life (QoL). Since there is still small number of studies that predominantly investigated QoL in patients with MMN, we sought to analyze QoL in these patients. MATERIALS AND METHODS: Our study comprised 17 patients diagnosed with MMN at the same clinic. Following scales were used: SF-36 questionnaire, INCAT disability scale, Krupp's Fatigue Severity scale, and Beck Depression Inventory. RESULTS: Physical domains of QoL were slightly more affected than mental ones, but with no statistical significance (64.8 ±â€¯22.3 vs. 70.0 ±â€¯19.5, p > 0.05). Total SF-36 score was 69.2 ±â€¯19.9. INCAT arm disability score at testing was found to correlate with the total SF-36 score (rho = -0.603, p < 0.05). INCAT arm disability score at diagnosis (rho = -0.57, p < 0.05) and at testing (rho = -0.48, p = 0.05) correlated with physical composite score (PCS). Disease duration (rho = -0.51, p < 0.05) and INCAT arm disability score at testing (rho = -0.60, p = 0.01) were associated with mental composite score (MCS). CONCLUSION: QoL in patients with MMN was reduced, especially in physical domains. Although arm disability was the most significant parameter which affected QoL of MMN patients in both physical and mental aspects, longer disease duration should not be underestimated as a psychological burden for these patients.

Body composition analysis in patients with myotonic dystrophy types 1 and 2.

INTRODUCTION: To date, there are only several reports on body composition in myotonic dystrophy type 1 (DM1) and there are no data for myotonic dystrophy type 2 (DM2). The aim was to analyze body composition of patients with DM1 and DM2, and its association with socio-demographic and clinical features of the diseases. METHODS: There were no statistical differences in sociodemographic features between 20 DM1 patients and 12 DM2 patients. Body composition was assessed by DEXA (dual-energy x-ray absorptiometry). A three-compartment model was used: bone mineral content (BMC), fat mass (FM), and lean tissue mass (LTM). RESULTS: Patients with DM1 and DM2 had similar total body mass (TBM), BMC, FM, and LTM. Patients with DM1 had higher trunk-limb fat index (TLFI) in comparison to DM2 patients which indicates visceral fat deposition in DM1 (1.16 ± 0.32 for DM1 vs. 0.87 ± 0.23 for DM2, p < 0.05). Right ribs bone mineral density was lower in DM2 group (0.68 ± 0.07 g/cm2 vs. 0.61 ± 0.09 g/cm2, p < 0.05). Higher percentage of FM in legs showed correlation with lower strength of the upper leg muscles in DM1 (ρ = - 0.47, p < 0.05). Higher muscle strength in DM2 patients was in correlation with higher bone mineral density (ρ = + 0.62, p < 0.05 for upper arm muscles, ρ = + 0.87, p < 0.01 for lower arm muscles, ρ = + 0.72, p < 0.05 for lower leg muscles). CONCLUSION: DM1 patients had visceral obesity, and percentage of FM correlated with a degree of muscle weakness in upper legs. In DM2 patients, degree of muscle weakness was in correlation with higher FM index and lower bone mineral density.

Heart involvement in patients with myotonic dystrophy type 2.

Myotonic dystrophy type 2 (DM2) is a slowly progressive, autosomal-dominant disease. This is a multisystemic disorder that affects the heart, which is one of the main causes of morbidity and mortality in DM2. The aim of the study was to define cardiac impairments in patients with DM2 and its association with sociodemographic and clinical features of patients. This retrospective study comprised 62 adult patients with DM2 hospitalized at the Neurology Clinic, Clinical Center of Serbia from 2013 until 2018, who underwent electrocardiography (ECG) and echocardiography examinations. Hypertension was observed in 42% of DM2 patients. One-fifth of DM2 patients had bradycardia, while other conduction and rhythm impairments were rare. Only one patient had a pacemaker implanted because of the first degree AV block associated with incomplete left bundle branch block. Echocardiography showed diastolic dysfunction of the left ventricle in 44% of patients, while systolic dysfunction was found in only 4%. Cardiomyopathy was observed in 18% of patients, of whom three-fourth had dilated type. Cardiac conduction and rhythm defects are relatively rare in DM2, while diastolic dysfunction is common. This suggests that regular ECG and echocardiography screening is needed in DM2. Adequate therapy should be introduced in patients with DM2 on time to reduce the frequency of heart complications and to prevent premature death.

Repeat Interruptions Modify Age at Onset in Myotonic Dystrophy Type 1 by Stabilizing DMPK Expansions in Somatic Cells.

CTG expansions in DMPK gene, causing myotonic dystrophy type 1 (DM1), are characterized by pronounced somatic instability. A large proportion of variability of somatic instability is explained by expansion size and patient's age at sampling, while individual-specific differences are attributed to additional factors. The age at onset is extremely variable in DM1, and inversely correlates with the expansion size and individual-specific differences in somatic instability. Three to five percent of DM1 patients carry repeat interruptions and some appear with later age at onset than expected for corresponding expansion size. Herein, we characterized somatic instability of interrupted DMPK expansions and the effect on age at onset in our previously described patients. Repeat-primed PCR showed stable structures of different types and patterns of repeat interruptions in blood cells over time and buccal cells. Single-molecule small-pool PCR quantification of somatic instability and mathematical modeling showed that interrupted expansions were characterized by lower level of somatic instability accompanied by slower progression over time. Mathematical modeling demonstrated that individual-specific differences in somatic instability had greater influence on age at onset in patients with interrupted expansions. Therefore, repeat interruptions have clinical importance for disease course in DM1 patients due to stabilizing effect on DMPK expansions in somatic cells.

Myotonic Dystrophy Type 2 - Data from the Serbian Registry.

BACKGROUND: Myotonic dystrophy type 2 (DM2) is a multisystem disorder, mostly presented with mild but heterogeneous spectrum of symptoms. OBJECTIVE: The aim of this research was to provide detailed sociodemographic, clinical and laboratory data of a large DM2 cohort from the Serbian registry. METHODS: In 2008, we started to prospectively enter data of all DM patients. We also retrospectively collected data of patients hospitalized from 1990 until 2008. RESULTS: At the end of 2017, registry comprised 87 (68%) of 128 genetically confirmed DM2 patients in Serbia, i.e. 1.2 registered cases per 100,000 inhabitants. Female subjects were more prevalent (63%). The diagnostic delay was 11.8±11.3 years. The most common first symptoms in our patients were lower limb weakness, handgrip myotonia and limb pain, although some percentage of patients presented with cataracts or extrapyramidal symptoms and signs. Lens opacities were present in 75% of patients. Severe ECG abnormalities were noted in 8% and pacemaker was implanted in 5% of DM2 subjects. Pulmonary restriction was observed in 10% of DM2 patients. Insulin resistance and diabetes mellitus were frequent in our cohort (21% and 17%, respectively). Male subjects more frequently had snoring, baldness, sterility, polyneuropathy, lower HDL and higher glycaemia, while waddling gait and increased muscle reflexes were more common in females. CONCLUSIONS: This registry offers a spectrum of different features presented in Serbian DM2 population, which could be at service of earlier diagnosis and better treatment.

Eight years after an international workshop on myotonic dystrophy patient registries: case study of a global collaboration for a rare disease.

BACKGROUND: Myotonic Dystrophy is the most common form of muscular dystrophy in adults, affecting an estimated 10 per 100,000 people. It is a multisystemic disorder affecting multiple generations with increasing severity. There are currently no licenced therapies to reverse, slow down or cure its symptoms. In 2009 TREAT-NMD (a global alliance with the mission of improving trial readiness for neuromuscular diseases) and the Marigold Foundation held a workshop of key opinion leaders to agree a minimal dataset for patient registries in myotonic dystrophy. Eight years after this workshop, we surveyed 22 registries collecting information on myotonic dystrophy patients to assess the proliferation and utility the dataset agreed in 2009. These registries represent over 10,000 myotonic dystrophy patients worldwide (Europe, North America, Asia and Oceania). RESULTS: The registries use a variety of data collection methods (e.g. online patient surveys or clinician led) and have a variety of budgets (from being run by volunteers to annual budgets over €200,000). All registries collect at least some of the originally agreed data items, and a number of additional items have been suggested in particular items on cognitive impact. CONCLUSIONS: The community should consider how to maximise this collective resource in future therapeutic programmes.