Decreased quality of life in Duchenne muscular disease patients related to functional neurological and cardiac impairment.

In this prospective study involving 37 Duchenne muscular dystrophy (DMD) patients aged 8-18 years and older, we examined the impact of neurological and cardiac factors on quality of life (QoL). Our findings revealed a negative correlation between upper limb movement and overall mobility, self-service, and usual activities. Ambulatory and non-ambulatory DMD patients showed significant differences in mobility-related parameters. Cardiac evaluations demonstrated associations between mitral annular plane systolic excursion (MAPSE) and mobility-related aspects. The PEDSQL 3.0 neuromuscular model questionnaire further highlighted age-related and movement-related correlations with QoL. The loss of ambulatory status and reduced upper limb movement were negatively associated with QoL, while upper limb movement positively correlated with septal MAPSE. However, no significant associations were found between MAPSE and anxiety/depression. These findings underscore the multifaceted impact of DMD on QoL and emphasize the importance of considering both neurological and cardiac factors in comprehensive patient care.

Trunk muscle dysfunction in patients with myotonic dystrophy type 2 and its contribution to chronic low back pain.

Introduction: Myotonic dystrophy type 2 (MD2) presents with a varied manifestation. Even though the myopathy in these patients is more widespread, axial musculature involvement is one of the most prominent conditions. MD2 patients also often report chronic low back pain (CLBP). The purpose of this study was to evaluate trunk muscle function, including respiratory muscles, in patients with MD2 and to compare it with healthy controls, to determine the occurrence of CLBP in patients with MD2, and to assess whether trunk muscle dysfunction increases the risk of CLBP in these patients. Methods: We enrolled 40 MD2 patients (age range 23 to 76 years, 26 women). A comprehensive battery of tests was used to evaluate trunk muscle function. The tests consisted of quantitative muscle strength testing of low back extensor muscles and respiratory muscles and the assessment of trunk muscle endurance. A neurological evaluation contained procedures assessing the distribution of muscle weakness, myotonia, and pain, and used questionnaires focused on these items and on disability, depression, and physical activity. Results: The results of this study suggest that patients with MD2 show significant dysfunction of the trunk muscles, including the respiratory muscles, expressed by decreased muscle strength and endurance. The prevalence of CLBP in patients with MD2 was 52.5%. Based on our analysis, the only independent significant risk factor for CLBP in these patients was maximal isometric lower back extensor strength in a prone position ≤ 15.8 kg (OR = 37.3). Other possible risk factors were severity of myotonia and reduced physical activity. Conclusion: Outcomes of this study highlighted the presence of axial muscle dysfunction, respiratory muscle weakness, and frequent occurrence of CLBP together with its risk factors in patients with MD2. We believe that the findings of this study may help in management and prevention programs for patients with MD2.

Genetic findings in Czech patients with limb girdle muscular dystrophy.

Limb girdle muscular dystrophies (LGMD) are a genetically heterogeneous group of muscular dystrophies. The study presents an overview of molecular characteristics of a large cohort of LGMD patients who are representative of the Czech LGMD population. We present 226 LGMD probands in which 433 mutant alleles carrying 157 different variants with a supposed pathogenic effect were identified. Fifty-four variants have been described only in the Czech LGMD population so far. LGMD R1 caplain3-related is the most frequent subtype of LGMD involving 53.1% of patients with genetically confirmed LGMD, followed by LGMD R9 FKRP-related (11.1%), and LGMD R12 anoctamin5-related (7.1%). If we consider identified variants, then all but five were small-scale variants. One large gene deletion was identified in the LAMA2 gene and two deletions in each of CAPN3 and SGCG. We performed comparison our result with other published studies. The results obtained in the Czech LGMD population clearly differ from the outcome of other LGMD populations in two aspects-we have a more significant proportion of patients with LGMD R1 calpain3-related and a smaller proportion of LGMD R2 dysferlin-related.

Adherence and Effect of Home-Based Rehabilitation with Telemonitoring Support in Patients with Chronic Non-Specific Low Back Pain: A Pilot Study.

Home-based exercises have been on the rise recently. This pilot study aimed to assess the adherence and effect of a home-based rehabilitation programme using telemonitoring in patients with chronic non-specific low back pain (CNLBP). Twenty-seven patients with CNLBP were enrolled in the study, each of whom underwent a neurological assessment, including patient-oriented measures and a functional assessment-a battery of tests that comprehensively evaluated trunk muscle function. The rehabilitation programme lasted 18 weeks and included daily home-based exercises. A mobile application or an exercise diary was used to monitor compliance. Adherence to the programme was excellent for both the diary and mobile application groups, with 82.3% in the diary group exercising at least once a day and 72.9% twice a day, and 94.8% in the mobile application group exercising at least once a day and 86.6% twice a day. Both patient-oriented and functional outcomes improved significantly; however, the relative changes of the parameters in these two groups did not correlate, which supports the idea that trunk muscle function does not directly relate to patient complaints and that CNLBP is a multifactorial issue. This model of rehabilitation programme should be used in clinical practice, as its adherence and effectiveness seem noticeable.

Telemedicine in Neuromuscular Diseases During Covid-19 Pandemic: ERN-NMD European Survey.

BACKGROUND: Telemedicine (TM) contributes to bridge the gap between healthcare facilities and patients' homes with neuromuscular disease (NMD) because of mobility issues. However, its deployment is limited due to difficulties evaluating subtle neurological signs such as mild weakness or sensory deficits. The COVID-19 pandemic has disrupted healthcare delivery worldwide, necessitating rapid measures implementation by health care providers (HCPs) to protect patients from acquiring SARS-CoV-2 while maintaining the best care and treatment. OBJECTIVES: Given the challenges faced by remote healthcare assistance of NMD patients, we aim to evaluate the use of TM in NMD during the COVID-19 pandemic. METHODS: Based on the Model for Assessment-of-Telemedicine-Applications (MAST), we conducted a survey amongst clinicians of the ERN EURO NMD (European-Reference-Network-for-Rare-Neuromuscular-Diseases). RESULTS: Based on 42 responses over 76 expected ones, our results show that the COVID-19 pandemic significantly increased the number of HCPs using TM (from 60% to 100%). The TM types most used during the COVID-19 period are teleconsultation and consultation by phone, particularly in the context of symptoms worsening in NMD patients with COVID-19 infection. Most European HCPs were satisfied when using TM but as a complementary option to physical consultations. Many responses addressed the issue of technical aspects needing improvement, particularly for elderly patients who need caregivers' assistance for accessing the TM platform. CONCLUSIONS: TM has been essential during COVID-19, but its use still presents some limitations for NMD patients with cognitive deficits or for first-time diagnosis. Thus, TM should be used as complement to, rather than substitute, for face-to-face consultations.

Predictive factors for a severe course of COVID-19 infection in myasthenia gravis patients with an overall impact on myasthenic outcome status and survival.

BACKGROUND AND PURPOSE: Myasthenia gravis (MG) patients could be a vulnerable group in the pandemic era of coronavirus 2019 (COVID-19) mainly due to respiratory muscle weakness, older age and long-term immunosuppressive treatment. We aimed to define factors predicting the severity of COVID-19 in MG patients and risk of MG exacerbation during COVID-19. METHODS: We evaluated clinical features and outcomes after COVID-19 in 93 MG patients. RESULTS: Thirty-five patients (38%) had severe pneumonia and we recorded 10 deaths (11%) due to COVID-19. Higher forced vital capacity (FVC) values tested before COVID-19 were shown to be protective against severe infection (95% CI 0.934-0.98) as well as good control of MG measured by the quantified myasthenia gravis score (95% CI 1.047-1.232). Long-term chronic corticosteroid treatment worsened the course of COVID-19 in MG patients (95% CI 1.784-111.43) and this impact was positively associated with dosage (p = 0.005). Treatment using azathioprine (95% CI 0.448-2.935), mycophenolate mofetil (95% CI 0.91-12.515) and ciclosporin (95% CI 0.029-2.212) did not influence the course of COVID-19. MG patients treated with rituximab had a high risk of death caused by COVID-19 (95% CI 3.216-383.971). Exacerbation of MG during infection was relatively rare (15%) and was not caused by remdesivir, convalescent plasma or favipiravir (95% CI 0.885-10.87). CONCLUSIONS: As the most important predictors of severe COVID-19 in MG patients we identified unsatisfied condition of MG with lower FVC, previous long-term corticosteroid treatment especially in higher doses, older age, the presence of cancer, and recent rituximab treatment.

Anti-Müllerian hormone as an ovarian reserve marker in women with the most frequent muscular dystrophies.

Some muscular dystrophies may have a negative impact on fertility. A decreased ovarian reserve is 1 of the factors assumed to be involved in fertility impairment. AMH (anti-Müllerian hormone) is currently considered the best measure of ovarian reserve.A total of 21 females with myotonic dystrophy type 1 (MD1), 25 females with myotonic dystrophy type 2 (MD2), 12 females with facioscapulohumeral muscular dystrophy (FSHD), 12 female carriers of Duchenne muscular dystrophy mutations (cDMD) and 86 age-matched healthy controls of reproductive age (range 18 - 44 years) were included in this case control study. An enzymatically amplified 2-site immunoassay was used to measure serum AMH level.The MD1 group shows a significant decrease of AMH values (median 0.7 ng/mL; range 0 - 4.9 ng/mL) compared with age-matched healthy controls (P < .01). AMH levels were similar between patients and controls in terms of females with MD2 (P = .98), FSHD (P = .55) and cDMD (P = .60).This study suggests decreased ovarian reserve in women with MD1, but not in MD2, FSHD and cDMD.

The Association of methylprednisolone dosing to cessation of myotonia in a patient with myotonic dystrophy type 1.

We report the case of a patient suffering from duplicity of myotonic dystrophy type 1 and ulcerative colitis whose treatment for ulcerative colitis included repeated administrations of descending doses of methylprednisolone and in whom we found an association between methylprednisolone dosing and cessation of myotonia. Myotonia severity was expressed as relaxation time after voluntary contraction and as a patient-reported outcome using the Czech version of the Myotonia Behavior Scale. The patient was being treated for a flare of ulcerative colitis, starting with 32 mg of methylprednisolone and reducing the dose by 4 mg a week. The symptoms of myotonia began to wear off three weeks after starting methylprednisolone and had totally disappeared by four weeks after starting methylprednisolone. The first symptoms of myotonia returned about a month after the last dose of methylprednisolone and reached a peak of severity more than two months after the final dose.

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.

Quantitative myotonia assessment with a commercially available dynamometer in myotonic dystrophy types 1 and 2.

INTRODUCTION: The objective of this study was to develop a simple method for quantitative assessment of myotonia in patients with myotonic dystrophy type 1 (DM1) and DM2, to compare the myotonia severity, and to correlate this objective outcome with a subjective scale, the Myotonia Behaviour Scale (MBS). METHODS: A commercially available dynamometer was used for all measurements. The relaxation time after voluntary contraction was measured in 20 patients with DM1, 25 patients with DM2, and 35 healthy controls. RESULTS: The average relaxation time was 0.17 s in controls, 2.96 s in patients with DM1, and 0.4 s in patients with DM2. The correlation between relaxation time and MBS score was significant, 0.627 in patients with DM1 and 0.581 in patients with DM2. DISCUSSION: Our method provides a valid and reliable quantitative measure of grip myotonia suitable as an outcome measure in clinical trials and as part of routine examinations to gather data on the natural history of myotonic disorders. Muscle Nerve 59:431-435, 2019.

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.

Autosomal recessive limb-girdle muscular dystrophies in the Czech Republic.

BACKGROUND: Autosomal recessive limb-girdle muscular dystrophies (LGMD2) include a number of disorders with heterogeneous etiology that cause predominantly weakness and wasting of the shoulder and pelvic girdle muscles. In this study, we determined the frequency of LGMD subtypes within a cohort of Czech LGMD2 patients using mutational analysis of the CAPN3, FKRP, SGCA, and ANO5 genes. METHODS: PCR-sequencing analysis; sequence capture and targeted resequencing. RESULTS: Mutations of the CAPN3 gene are the most common cause of LGMD2, and mutations in this gene were identified in 71 patients in a set of 218 Czech probands with a suspicion of LGMD2. Totally, we detected 37 different mutations of which 12 have been described only in Czech LGMD2A patients. The mutation c.550delA is the most frequent among our LGMD2A probands and was detected in 47.1% of CAPN3 mutant alleles. The frequency of particular forms of LGMD2 was 32.6% for LGMD2A (71 probands), 4.1% for LGMD2I (9 probands), 2.8% for LGMD2D (6 probands), and 1.4% for LGMD2L (3 probands).Further, we present the first results of a new approach established in the Czech Republic for diagnosis of neuromuscular diseases: sequence capture and targeted resequencing. Using this approach, we identified patients with mutations in the DYSF and SGCB genes. CONCLUSIONS: We characterised a cohort of Czech LGMD2 patients on the basis of mutation analysis of genes associated with the most common forms of LGMD2 in the European population and subsequently compared the occurrence of particular forms of LGMD2 among countries on the basis of our results and published studies.

CLCN1 mutations in Czech patients with myotonia congenita, in silico analysis of novel and known mutations in the human dimeric skeletal muscle chloride channel.

Myotonia congenita (MC) is a genetic disease caused by mutations in the skeletal muscle chloride channel gene (CLCN1) encoding the skeletal muscle chloride channel (ClC-1). Mutations of CLCN1 result in either autosomal dominant MC (Thomsen disease) or autosomal recessive MC (Becker disease). The ClC-1 protein is a homodimer with a separate ion pore within each monomer. Mutations causing recessive myotonia most likely affect properties of only the mutant monomer in the heterodimer, leaving the wild type monomer unaffected, while mutations causing dominant myotonia affect properties of both subunits in the heterodimer. Our study addresses two points: 1) molecular genetic diagnostics of MC by analysis of the CLCN1 gene and 2) structural analysis of mutations in the homology model of the human dimeric ClC-1 protein. In the first part, 34 different types of CLCN1 mutations were identified in 51 MC probands (14 mutations were new). In the second part, on the basis of the homology model we identified the amino acids which forming the dimer interface and those which form the Cl(-) ion pathway. In the literature, we searched for mutations of these amino acids for which functional analyses were performed to assess the correlation between localisation of a mutation and occurrence of a dominant-negative effect (corresponding to dominant MC). This revealed that both types of mutations, with and without a dominant-negative effect, are localised at the dimer interface while solely mutations without a dominant-negative effect occur inside the chloride channel. This work is complemented by structural analysis of the homology model which provides elucidation of the effects of mutations, including a description of impacts of newly detected missense mutations.

Towards a predictive model for post-stroke delirium.

PRIMARY OBJECTIVE: To assess predisposing and precipitating risk factors and create a predictive model for post-stroke delirium. RESEARCH DESIGN: A prospective observational study in a cohort of consecutive patients with ischemic stroke or intracerebral haematoma admitted within 24 hours of stroke onset. METHODS: Patients were assessed daily for delirium during the first week by means of DSM-IV criteria and risk factors were recorded. RESULTS: One hundred patients completed a 7-day evaluation (47 women and 53 men, median age 77 years). An episode of delirium was detected in 43 patients (43%). Using multivariate logistic regression, a predictive statistical model was developed that utilized independent risk factors: age (OR = 1.08; 95% CI = 1.02-1.15); intracerebral haemorrhage (OR = 6.11; 95% CI = 1.62-22.98), lesion volume > 40 ccm (OR = 3.99; 95% CI = 1.29-12.39) and either elevated gamma-glytamyl transferase (OR = 4.88; 95% CI = 1.45-16.35) and elevated serum bilirubin (OR = 3.70; 95% CI = 1.32-10.38) or maximum sequential organ failure assessment score >2 (OR = 3.33; 95% CI = 1.06-10.45) with acceptable sensitivity and specificity (69.0% and 80.7%). In ischemic strokes, total anterior circulation infarctions were more frequently associated with delirium (73.3% developed delirium) compared with the remainder of the groups combined (p = 0.004; OR = 6.66; 95% CI = 1.85-24.01). CONCLUSION: Higher age, metabolic disturbances, intracerebral haemorrhage and larger ischemic hemispheric strokes increase the risk of post-stroke delirium.

Poststroke delirium incidence and outcomes: validation of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU).

OBJECTIVE: To describe the epidemiology and time spectrum of delirium using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and to validate a tool for delirium assessment in patients in the acute poststroke period. DESIGN: A prospective observational cohort study. SETTING: The stroke unit of a university hospital. PATIENTS: A consecutive series of 129 patients with stroke (with infarction or intracerebral hemorrhage, 57 women and 72 men; mean age, 72.5 yrs; age range, 35-93 yrs) admitted to the stroke unit of a university hospital were evaluated for delirium incidence. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Criterion validity and overall accuracy of the Czech version of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) were determined using serial daily delirium assessments with CAM-ICU by a junior physician compared with delirium diagnosis by delirium experts using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria that began the first day after stroke onset and continued for at least 7 days. Cox regression models using time-dependent covariate analysis adjusting for age, gender, prestroke dementia, National Institutes of Stroke Health Care at admission, first-day Sequential Organ Failure Assessment, and asphasia were used to understand the relationships between delirium and clinical outcomes. An episode of delirium based on reference Diagnostic and Statistical Manual assessment was detected in 55 patients with stroke (42.6%). In 37 of these (67.3%), delirium began within the first day and in all of them within 5 days of stroke onset. A total of 1003 paired CAM-ICU/Diagnostic and Statistical Manual of Mental Disorders daily assessments were completed. Compared with the reference standard for diagnosing delirium, the CAM-ICU demonstrated a sensitivity of 76% (95% confidence interval [CI] 55% to 91%), a specificity of 98% (95% CI 93% to 100%), an overall accuracy of 94% (95% CI 88% to 97%), and high interrater reliability (κ = 0.94; 95% CI 0.83-1.0). The likelihood ratio of the CAM-ICU in the diagnosis of delirium was 47 (95% CI 27-83). Delirium was an independent predictor of increased length of hospital stay (hazard ratio 1.63; 95% CI 1.11-2.38; p = .013). CONCLUSIONS: Poststroke delirium may frequently be detected provided that the testing algorithm is appropriate to the time profile of poststroke delirium. Early (first day after stroke onset) and serial screening for delirium is recommended. CAM-ICU is a valid instrument for the diagnosis of delirium and should be considered an aid in delirium screening and assessment in future epidemiologic and interventional studies in patients with stroke.

Are subjects with spondylotic cervical cord encroachment at increased risk of cervical spinal cord injury after minor trauma?

The aim of the study was to analyse the risk of symptomatic myelopathy after minor trauma in patients with asymptomatic spondylotic cervical spinal cord encroachment (ASCCE). In a cohort of 199 patients with ASCCE, previously followed prospectively in a study investigating progression into symptomatic myelopathy, the authors looked retrospectively for traumatic episodes that may have involved injury to the cervical spine. A questionnaire and data file analysis were employed to highlight whatever hypothetical relationship might emerge with the development of symptomatic myelopathy. Fourteen traumatic episodes in the course of a follow-up of 44 months (median) were recorded in our group (who had been instructed to avoid risky activities), with no significant association with the development of symptomatic myelopathy (found in 45 cases). Only three minor traumatic events without fracture of the cervical spine were found among the symptomatic myelopathy cases, with no chronological relationship between trauma and myelopathy. Furthermore, 56 traumatic spinal cord events were found before the diagnosis of cervical cord encroachment was established, with no correlation to either type of compression (discogenic vs osteophytic). In conclusion, the risk of spinal cord injury after minor trauma of the cervical spine in patients with ASCCE appeared to be low in our cohort provided risky activities in these individuals are restricted. Implementation of preventive surgical decompression surgery into clinical practice in these individuals should be postponed until better-designed studies provide proof enough for it to take precedence over a conservative approach.

Point mutations in Czech DMD/BMD patients and their phenotypic outcome.

Duchenne and Becker muscular dystrophies (DMD/BMD) are associated with mutations in the DMD gene. We determined the mutation status of 47 patients with dystrophinopathy without deletion or duplication in the DMD gene by screening performed by reverse transcription-PCR, protein truncation test, and DNA sequencing. We describe three patients with a mutation creating a premature termination codon (p.E55X, p.E1110X, and p.S3497PfsX2) but with a mild phenotype, which present three different ways of rescuing the DMD phenotype. In one patient we detected the insertion of a repetitive sequence AluYa5 in intron 56, which led to skipping of exon 57. Further, using quantitative analysis of DMD mRNA carrying various mutated alleles, we examine levels of mRNA degradation due to nonsense mediated mRNA decay. The quantity of dystrophin mRNA is different depending on the presence of a mutation leading to a premature termination codon, and position of the analysed mRNA region with respect to its 5' end or 3' end. Average relative amounts of DMD mRNAs carrying a premature termination codon is 48% and 17%, when using primers amplifying the 5' and 3' cDNA regions, respectively.

Presymptomatic spondylotic cervical myelopathy: an updated predictive model.

Spondylotic cervical cord compression detected by imaging methods is a prerequisite for the clinical diagnosis of spondylotic cervical myelopathy (SCM). Little is known about the spontaneous course and prognosis of clinically "silent" presymptomatic spondylotic cervical cord compression (P-SCCC). The aim of the present study was to update a previously published model predictive for the development of clinically symptomatic SCM, and to assess the early and late risks of this event in a larger cohort of P-SCCC subjects. A group of 199 patients (94 women, 105 men, median age 51 years) with magnetic resonance signs of spondylotic cervical cord compression, but without clear clinical signs of myelopathy, was followed prospectively for at least 2 years (range 2-12 years). Various demographic, clinical, imaging, and electrophysiological parameters were correlated with the time for the development of symptomatic SCM. Clinical evidence of the first signs and symptoms of SCM within the follow-up period was found in 45 patients (22.6%). The 25th percentile time to clinically manifested myelopathy was 48.4 months, and symptomatic SCM developed within 12 months in 16 patients (35.5%). The presence of symptomatic cervical radiculopathy and electrophysiological abnormalities of cervical cord dysfunction detected by somatosensory or motor-evoked potentials were associated with time-to-SCM development and early development (< or =12 months) of SCM, while MRI hyperintensity predicted later (>12 months) progression to symptomatic SCM. The multivariate predictive model based on these variables correctly predicted early progression into SCM in 81.4% of the cases. In conclusion, electrophysiological abnormalities of cervical cord dysfunction together with clinical signs of cervical radiculopathy and MRI hyperintensity are useful predictors of early progression into symptomatic SCM in patients with P-SCCC. Electrophysiological evaluation of cervical cord dysfunction in patients with cervical radiculopathy or back pain is valuable. Meticulous follow-up is justified in high-risk P-SCCC cases.

Quantitative analysis of CAPN3 transcripts in LGMD2A patients: involvement of nonsense-mediated mRNA decay.

Limb girdle muscular dystrophy type 2A (LGMD2A) is caused by single or small nucleotide changes widespread along the CAPN3 gene, which encodes the muscle-specific proteolytic enzyme calpain-3. About 356 unique allelic variants of CAPN3 have been identified to date. We performed analysis of the CAPN3 gene in LGMD2A patients at both the mRNA level using reverse transcription-PCR, and at the DNA level using PCR and denaturing high performance liquid chromatography. In four patients, we detected homozygous occurrence of a missense mutation or an in-frame deletion at the mRNA level although the DNA was heterozygous for this mutation in conjunction with a frame-shift mutation. The relationship observed in 12 patients between the quantity of CAPN3 mRNA, determined using real-time PCR, and the genotype leads us to propose that CAPN3 mRNAs which contain frame-shift mutations are degraded by nonsense-mediated mRNA decay. Our results illustrate the importance of DNA analysis for reliable establishment of mutation status, and provide a new insight into the process of mRNA decay in cells of LGMD2A patients.