Commonly available outcome measures for use in Indian boys with Duchenne muscular dystrophy

Management of a 25-Year-Old Female Patient With Limb-Girdle Muscular Dystrophy With Physiotherapy: A Case Report

Limb-girdle muscular dystrophy (LGMD) is a collection of neuromuscular diseases that develop gradually and are rare, genetically, and clinically diverse. The weakness in muscles affecting the shoulder and pelvic girdles is a defining feature of LGMD. Calpainopathy is another name for limb-girdle muscular dystrophy type 2A (LGMD2A). Limb-girdle muscular dystrophy type 2A results from alterations in the calpain-3 (CAPN3) gene, which results in a CAPN3 protein shortage. Gower's sign is most commonly found in LGMD2A. The prevalence ranges from one person in every 14,500 to one in every 123,000. We present a case of a 25-year-old hypotensive female patient who complained of weakness in all four limbs and easy fatigue with a positive Gower's sign. For subsequent management, the neurologist referred the patient to the physical therapy department. The physical therapy goals included enhanced muscle strength, increased joint mobility, reduced fatigue, normalizing gait, and building dynamic balance and postural stability. Diagnosing LGMD clinical variability is important, emphasizing the importance of precise subtype identification and tailoring therapy. Tackling specific muscular deficits and functional restrictions emerges as a critical component in the holistic care of LGMD by physiotherapists. Continuous monitoring and evaluation using appropriate scales and measurements are essential for tracking performance and tailoring treatment strategies. Regular follow-up consultations with the physiotherapist are needed to identify changes in an individual's health and alter the treatment plan accordingly.

Development and Validation of an Outpatient Clinical Predictive Score for the Diagnosis of Duchenne Muscular Dystrophy/Becker Muscular Dystrophy in Children Aged 2-18 Years

Introduction

There is no bedside clinical examination-based prediction score for Duchenne muscular dystrophy/Becker muscular dystrophy (DMD/BMD) in children with neuromuscular diseases (NMDs) presenting with proximal limb-girdle weakness.

Methods

We compared the details of 200 cases of lower motor neuron type of weakness and had some proximal limb-girdle muscle weakness and divided them into 2 groups: with/without a confirmed diagnosis of DMD/BMD. We determined the predictive factors associated with a diagnosis of DMD/BMD using multivariate binary logistic regression. We assessed our proposed prognostic model using both discrimination and calibration and subsequently used the bootstrap method to successfully validate the model internally.

Results

A total of 121 patients had DMD/BMD and the rest of the patients had other diagnoses. Male gender, presence of Gower's sign, valley sign, toe walking, calf pseudohypertrophy, and tongue hypertrophy were independent predictors for a confirmed diagnosis of DMD/BMD and included in the final CVT2MG score (Calf pseudohypertrophy, Valley sign, Toe walking, Tongue hypertrophy, Male gender, and Gower's sign). The final model showed good discrimination (AUC = 87.4% [95% CI: 80.5-92.3%, P < 0.001]) and calibration (P = 0.57). A score of 6 or above appeared to be the best cutoff for discriminating between the DMD/BMD group and the rest of the group with both sensitivity and specificity of 98%. The interrater reliability was almost perfect between two pediatric neurologists and strong between a pediatric neurologist and a pediatric neurology trainee resident (k = 0.91 and 0.87).

Conclusion

The CVT2MG score has good sensitivity and specificity in predicting a confirmed diagnosis of DMD/BMD in subsequent tests.

Deflazacort dose optimization and safety evaluation in Duchenne muscular dystrophy (DOSE): A randomized, double-blind non-inferiority trial

BACKGROUND

US food and drug administration has recently approved deflazacort for Duchenne muscular dystrophy (DMD) and recommended the dosage of 0.9 mg/kg/d for patients aged ≥5years. However, data assessing the minimal efficacious dose and need of dose-titration based on age or disease severity is limited.

OBJECTIVE

To determine whether deflazacort 0.45 mg/kg/d (proposed lower dosage) is non-inferior to 0.9 mg/kg/d among newly diagnosed patients with DMD.

METHOD

A double-blinded, non-inferiority, randomized trial, conducted between December 2018 and July 2020. Newly diagnosed patient aged 5-15 years with genetic or muscle biopsy confirmed DMD and baseline 6-min walk distance (6MWD) > 150 m were screened. Patients were randomly assigned (1:1), stratified to prespecified subgroups by age (≤7years and >7years), and baseline 6MWD (≤350 m and >350 m), to receive either 0.45 mg/kg/d or 0.9 mg/kg/d regimens. The primary endpoint was the change in 6MWD, from baseline to week-24 of intervention. The trial was powered with a predefined, non-inferiority margin of 30 m. The analyses were by modified intention-to-treat (mITT).

RESULT

A total of 97 patients were enrolled, 40 receiving 0.45 mg/kg/d and 45 receiving 0.9 mg/kg/d deflazacort comprised of mITT population. For primary endpoint analysis the mean (SD) change in 6MWD from baseline to week-24 was 9.7 m (41.5) in deflazacort 0.45 mg/kg/d, and 34.7 m (43.5) for 0.9 mg/kg/d. The mean difference in change in 6MWD across the group was 24.8 m (95% CI 6.7 to 43, p value 0.008). The mean difference in change in 6MWD in the subgroups of boys ≤7 years of age was 21.8 m (95% CI -0.82, 44.5, p = 0.059), with baseline 6MWD of >350 m was 19.9 m (95% CI -2.4, 42.4; p = 0.08). The incidence of combined moderate to severe treatment-related adverse events was significant in the 0.9 mg/kg/d group by week 24 (odds ratio 0.36 [95% CI, 0.14 to 0.89], p = 0.03).

DISCUSSION

The efficacy of proposed low dose deflazacort in comparison to the standard dose did not meet the prespecified criteria for non-inferiority. The low dose deflazacort was non-inferior in subgroup of patients with age ≤7 years and baseline 6MWD of >350 m.

TRIAL REGISTRATION

Clinical Trial Registry-India Identifier: CTRI/2019/02/017388.

Steroid Responsiveness in Duchenne Muscular Dystrophy - Predictive Value of Epigenetic Regulator Histone Deacetylase 2

OBJECTIVE

To find the role of an epigenetic regulator histone deacetylase (HDAC-2) in predicting steroid responsiveness in patients with Duchenne muscular dystrophy (DMD).

METHODS

Peripheral blood mononuclear cells were isolated from three milliliters of venous blood sample of patients with DMD for estimation of HDAC-2 levels. The patients were then given prednisolone at 0.75 mg/kg/d and followed up for response. Improvement in muscle power and timed function tests were evaluated 2 monthly for 6 mo. Side- effects of steroids were also noted.

RESULTS

HDAC-2 values showed a linear correlation with improvement in muscle power at 6 mo as reflected in direct assessment and in various functional tests. When ≥3 point change from baseline was considered in power of various muscle groups at 6 mo as cut off to distinguish good responders (GR) from poor responders (PR) of steroid, a HDAC-2 value of ≥4.40 seemed to be 92.6% sensitive and 100% specific to distinguish GRs.

CONCLUSIONS

The degree of improvement in power and various timed function tests at 6 mo could be predicted from the HDAC-2 value of the individual patient recorded at baseline. HDAC-2 levels at baseline might be a good biomarker for predicting steroid response in patients with DMD.