Diffusion Tensor Imaging Shows Differences Between Myotonic Dystrophy Type 1 and Type 2.

BACKGROUND: Myotonic Dystrophies type 1 and type 2 are hereditary myopathies with dystrophic muscle degeneration in varying degrees. Differences in muscle diffusion between both diseases have not been evaluated yet. OBJECTIVE: To evaluate the ability of muscle diffusion tensor imaging (mDTI) and Dixon fat-quantification to distinguish between Myotonic Dystrophy (DM) type 1 and type 2 and if both diseases show distinct muscle involvement patterns. METHODS: We evaluated 6 thigh and 7 calf muscles (both legs) of 10 DM 1, 13 DM 2 and 28 healthy controls (HC) with diffusion tensor imaging, T1w and mDixonquant sequences in a 3T MRI scanner. The quantitative mDTI-values axial diffusivity (λ1), mean diffusivity (MD), radial diffusivity (RD) and fractional anisotropy (FA) as well as fat-fraction were analysed. CTG-triplet repeat-length of DM 1 patients was correlated with diffusion metrics and fat-fraction. RESULTS: mDTI showed significant differences between DM 1 and DM 2 vs. healthy controls in diffusion parameters of the thigh (all p < 0.001) except for FA (p = 0.0521 / 0.8337). In calf muscles mDTI showed significant differences between DM 1 and DM 2 patients (all p < 0.0001) as well as between DM 1 patients and controls (all p = 0.0001). Thigh muscles had a significant higher fat-fraction in both groups vs. controls (p < 0.05). There was no correlation of CTG triplet length with mDTI values and fat-fraction. DISCUSSION: mDTI reveals specific changes of the diffusion parameters and fat-fraction in muscles of DM 1 and DM 2 patients. Thus, the quantitative MRI methods presented in this study provide a powerful tool in differential diagnosis and follow-up of DM 1 and DM 2, however, the data must be validated in larger studies.

Pathological spontaneous activity as a prognostic marker in chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: Monitoring of the disease course of patients with chronic inflammatory demyelinating polyneuropathy (CIDP) remains challenging because nerve conduction studies do not adequately correlate with functional disability. The prognostic value of pathological spontaneous activity (PSA) in needle electromyography (EMG) in different CIDP subgroups in a longitudinal context has, to date, not been analysed. We aimed to determine whether PSA was a prognostic marker or a marker of disease activity in a cohort of patients with CIDP. METHODS: A total of 127 patients with CIDP spectrum disorder were retrospectively analysed over 57 ± 47 months regarding the occurrence of PSA (fibrillations and positive sharp waves). The presence of PSA at diagnosis, newly occurring PSA, and continuously present PSA were longitudinally correlated with clinical disability using the Inflammatory Neuropathy Cause and Treatment Overall Disability Sum Score (INCAT-ODSS) and CIDP subtype. RESULTS: Pathological spontaneous activity occurred in 49.6% of all CIDP patients at first diagnosis. More frequent evidence of PSA was significantly associated with a higher INCAT-ODSS at the last follow-up. Continuous and new occurrence of PSA were associated with higher degree of disability at the last follow-up. The majority of patients with sustained evidence of PSA were characterized by an atypical phenotype, higher degree of disability, and the need for escalation of treatment. CONCLUSIONS: Pathological spontaneous activity was associated with a higher degree of disability and occurred more frequently in atypical CIDP variants according to the longitudinal data of a large cohort of patients with CIDP. Our results showed that EMG examination was an adequate marker for disease progression and should be evaluated during the disease course.

[Radiation-Induced Radiculopathy with Paresis of the Neck and Autochthonous Back Muscles with Additional Myopathy]. / Parese der Nacken- und autochthonen Rückenmuskulatur durch strahleninduzierte zervikale Radikulopathie mit Begleitmyopathie.

Radiation-induced tissue damage is caused by ionizing radiation mainly affecting the skin, vascular, neuronal or muscle tissue. Early damages occur within weeks and months while late damages may occur months or even decades after radiation.Radiation-induced paresis of the spine or the trunk muscles with camptocormia or dropped-head syndrome are rare but have already been described as long-term sequelae after treatment of Hodgkin's lymphoma. The differential diagnosis includes limb-girdle muscular dystrophy, fascioscapulohumeral muscular dystrophy (FSHD) or lysosomal storage diseases (e. g. Acid Maltase Deficiency). We present the case of a patient with long lasting diagnostics over many months due to different inconclusive results.

Side effects of anesthesia in DM2 as compared to DM1: a comparative retrospective study.

BACKGROUND AND PURPOSE: Myotonic dystrophy type 2 (DM2) is an adult-onset progressive multisystem disease. There have been no reported risks for anesthesia in DM2. METHODS: We assess the frequency, type, and severity of peri-operative complications under general and local anesthesia in genetically proven DM2. A retrospective multicenter study was conducted. RESULTS: Out of 320 DM2 patients, 134 participated by completing questionnaires (41, 88%), which were delivered by mail, and their clinical records were reviewed (class III evidence). A total of 121 patients had 340 operations in general anesthesia at an average age of 40.5 years (range 18-82); 132 (38.8%) general anesthesia were performed prior to DM2 onset, 187 (55.9%) after disease onset. A total of 212 (62.4%) of the interventions were performed without known DM2 diagnosis. In 120 (35.3%) interventions, DM2 was already diagnosed. The locations of surgery were lower abdomen (47%), peripheral extremities (46.8%), upper abdomen (3.8%), thorax (1.8%), and brain (0.6%). The overall frequency of severe complications was 0.6% (2 of 340). One incident was a post-operative development of rhabdomyolysis, hyperthermia, muscle weakness and renal failure; the others, prolonged muscular weakness and renal failure. Minor complications related to a general anesthesia were reported by 27 participants (20.2%). In 116 patients (86.6%), 342 interventions were performed in regional anesthesia. Minor complications were reported by 20.2% participants such as nausea (6.7%), muscular weakness and pain (5.9%), prolonged anesthesia (5.2%), circulatory insufficiency (2.9%), and shortness of breath (2.9%). CONCLUSION: The overall lower risk seems to be predominantly related to the minor respiratory involvement in DM2, than in myotonic dystrophy type 1 (DM1).

Mitofusin 2 gene mutation (R94Q) causing severe early-onset axonal polyneuropathy (CMT2A).

Charcot-Marie-Tooth disease (CMT) has been classified into two types: demyelinating forms (CMT1) and axonal forms (CMT2). Mutations in the CMT2A locus have been linked to the KIF1B and the mitofusin 2 (MFN2) genes. Here, we report a German patient with CMT2 with an underlying spontaneous mutation (c.281G-->A) in the MFN2 gene. Clinically, the patient presented with early-onset CMT that was not associated with additional central nervous system pathology. The disease course was rapidly progressive in the first years and slowed afterwards. We also suggest that single patients with early-onset axonal polyneuropathies should be screened for MFN2 mutations.

[Musculoskeletal pain as the most prominent feature in myotonic dystrophy type 2]. / Muskuloskelettaler Schmerz als Hauptsymptom bei myotoner Dystrophie Typ 2.

BACKGROUND: Myotonic dystrophy type 2/proximal myotonic myopathy (DM 2/PROMM) is an autosomal dominant multisystem disorder characterized by proximal muscle weakness, myotonia and musculoskeletal pain. PATIENTS AND METHODS: We describe five patients with DM 2/PROMM in whom musculoskeletal pain was the most prominent feature. We used the McGill Pain Questionnaire for standardized pain assessment. RESULTS: The patients reported multiple types of musculoskeletal pain including tenderness, cold-enhanced and exercise-related musculoskeletal pain. Exercise-induced or -enhanced musculoskeletal pain was indicated as the most disabling feature. CONCLUSIONS: Myotonic dystrophy type 2 should be considered as one of the differential diagnoses in patients with musculoskeletal pain. Family history and laboratory tests provide critical diagnostic clues.

Outcome and effect of pregnancy in myotonic dystrophy type 2.

The authors reviewed the obstetric histories of 42 women of 37 families with myotonic dystrophy type 2 (DM2). Nine women (21%) had the first symptoms during pregnancy and worsening in subsequent pregnancies. Of 96 pregnancies, 13% ended as early and 4% as late miscarriages. Preterm labor occurred in 50% of pregnancies resulting in 27% preterm deliveries in women with overt DM2 in pregnancy. There was no evidence of a congenital DM2.

LGMD 2I due to the common mutation 826C>A in the FKRP gene presenting as myopathy with vacuoles and paired-helical filaments.

We report on two unrelated patients clinically presenting with late-onset progressive limb girdle weakness; cardiomyopathy was seen in one patient. Muscle biopsy revealed a necrotic myopathy with numerous rimmed vacuoles, ultrastructurally typical paired-helical filaments, and reduced immunohistochemical staining for alpha-dystroglycan. Quadriceps sparing hereditary inclusion body myopathy due to mutations in GNE gene, and OPMD due to PABPN1 mutations were excluded, genetically. We detected a homozygous mutation of the FKRP gene (826C>A) in both patients. Mutations of FKRP have been reported in congenital muscular dystrophies, LGMD2I, cardiomyopathy and hyperCKemia, but not in myopathies with vacuoles and paired-helical filaments. Therefore, our findings further extend the morphological variability of muscular dystrophies due to FKRP mutations.

Corticosteroids for myasthenia gravis.

BACKGROUND: Although widely accepted as an appropriate immunosuppressive therapy, the efficacy of glucocorticosteroid treatment has only rarely been tested in controlled studies. OBJECTIVES: To assess the efficacy of glucocorticosteroids or adrenocorticotrophic hormone (ACTH) medication in autoimmune myasthenia gravis. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group Trials Register in July 2004, MEDLINE (from January 1966 to June 2004) and EMBASE (from January 1980 to June 2004). We also checked the bibliographies in reviews and the randomised trials and contacted their authors to identify additional published and unpublished data. SELECTION CRITERIA: From the articles identified we selected those open or controlled studies which allowed us to assess the outcome of treated and untreated patients at definite endpoints. Types of studies: quasi-randomised or randomised controlled trials. TYPES OF PARTICIPANTS: patients with myasthenia gravis of all ages and all degrees of severity. Types of interventions: any form of glucocorticosteroids or adrenocorticotrophic hormone treatment. Types of outcome measures:Primary outcome(1) improvement after at least three months in either the weakest muscles or all muscles. Secondary outcomes(1) proportion of patients improved after at least six months(2) proportion of patients in remission(3) number of episodes of worsening during the first six months(4) acetylcholine receptor antibody titres after at least three months of therapy. DATA COLLECTION AND ANALYSIS: Three authors extracted the data from the selected articles and one other checked them. MAIN RESULTS: A trial of adrenocorticotrophic hormone (43 patients) did not show any advantage compared with placebo for the treatment of ocular myasthenia gravis. Two double-blind trials compared prednisone with placebo for generalised myasthenia gravis. In the first (13 patients), the improvement was slightly greater in the prednisone group at six months. In the second (20 patients) which was a short-term trial, the improvement was significantly greater at two weeks. Two trials compared glucocorticosteroids with azathioprine (41 and 10 patients respectively). In one of these the rate of treatment failure was greater in the prednisone group. In a trial of glucocorticosteroids versus intravenous immunoglobulin (33 patients) no differences in treatment responses were encountered during a treatment period of 14 days. An open trial (39 patients) evaluating different corticosteroid doses revealed a shorter time to improvement in the high-dose group. However only limited evidence can be drawn from the available randomised controlled trials due to numerous and important methodological flaws. AUTHORS' CONCLUSIONS: Limited evidence from randomised controlled trials suggests that corticosteroid treatment offers significant short-term benefit in myasthenia gravis compared with placebo. This supports the conclusions of observational studies and expert opinion. Limited evidence from randomised controlled trials does not show any difference in efficacy between corticosteroids and either azathioprine or intravenous immunoglobulin.

Sudden cardiac death in myotonic dystrophy type 2.

Medical records and follow-up data were reviewed in 297 genetically proven myotonic dystrophy type 2 (DM2) patients. Patients were selected by the criteria of cardiac sudden death before age 45. Sudden death occurred in four patients, three of whom were cardiological asymptomatic, and one with a history of heart failure. Cardiac histopathology showed dilated cardiomyopathy in all, and conduction system fibrosis in two patients. Pathogenetic CCUG ribonuclear inclusions were demonstrable in cardiomyocytes.

Neuroleptic malignant syndrome in Kufs' disease.

A patient with adult neuronal ceroid lipofuscinosis (ANCL; Kufs' disease) is described in whom neuroleptic malignant syndrome occurred, initially presenting as catatonic syndrome. Comprehensive neuroimaging studies were conducted including FDG-PET, IBZM-SPECT, and beta-CIT-SPECT, electrophysiological examinations and an ex vivo contracture test exposing muscle biopsy specimens to neuroleptics. Collectively the results argued for an involvement of the muscle in neuroleptic malignant syndrome at least in ANCL.

Creatine monohydrate in DM2/PROMM: a double-blind placebo-controlled clinical study. Proximal myotonic myopathy.

The efficacy and safety of creatine monohydrate (Cr) in patients with myotonic dystrophy type 2/proximal myotonic myopathy were studied in a small placebo-controlled double-blind trial. Twenty patients received either Cr or placebo for 3 months. After 3 months, there were no significant differences of muscle strength as assessed by hand-held dynamometry, testing of maximum grip strength, Medical Research Council scoring, and the Neuromuscular Symptom Score between the two groups. Some measures indicated trends toward mild improvement with Cr. Myalgia improved in two patients.