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Susan T Iannaccone

Publications and source records attributed to Susan T Iannaccone.

13 recordsLinked to original sources
PubMed2006

Left ventricular function and response to enalapril in patients with duchenne muscular dystrophy during the second decade of life.

The role of angiotensin-converting enzyme inhibitors in the management of cardiomyopathy related to Duchenne muscular dystrophy has not been completely defined. The purposes of this study were to describe the response to enalapril and its relation to dystrophin mutation type, ventricular size, or age at the onset of left ventricular (LV) systolic dysfunction. Serial clinical and echocardiographic data from 50 patients with Duchenne muscular dystrophy (aged 10 to 20 years) were retrospectively reviewed. Twenty-seven patients (46%) developed LV systolic dysfunction (mean age 13.2 +/- 2.4 years). Ten (43%) responded to enalapril with the normalization of function. Responders and nonresponders developed LV systolic dysfunction at similar ages (p = 0.91). At the onset of LV systolic dysfunction, only 2 patients (1 responder, 1 nonresponder) had dilated left ventricles. The positive response to enalapril was sustained in 7 patients (median follow-up 23 months, range 5 to 58). No specific mutation was associated with the response to enalapril (p = 0.66) or predictive of the development of LV systolic dysfunction (p = 0.8). In conclusion, 10 of 26 patients (43%) with Duchenne muscular dystrophy responded to the use of enalapril with normalization of the shortening fraction. Age at the onset of LV systolic dysfunction and the type of mutation were not predictors of response to enalapril.

Adolescent↗
PubMed2006

The gross motor function measure is a valid and sensitive outcome measure for spinal muscular atrophy.

Spinal muscular atrophy is a genetic disease of the anterior horn cell with high morbidity rate in childhood. Certain drugs may be of benefit and are in or under consideration for Phase II trials. Outcome measures that are age appropriate and representative of disease activity remain under study. Several have not yet been validated for spinal muscular atrophy. The Gross Motor Function Measure is a measure of motor function. We showed previously that the Gross Motor Function Measure is a reliable outcome measure to assess motor function in children with spinal muscular atrophy. By collating our data from 40 spinal muscular atrophy patients, ages 5 through 17 years, we now show the validity of the Gross Motor Function Measure when compared to Quantitative Muscle Testing and ambulatory status in children with spinal muscular atrophy. The median for Gross Motor Function Measure total scores for walkers was 237 (range: 197-261) and for non-walkers, 64 (range: 4-177; P<0.0001) with no distributional overlap. We conclude that the Gross Motor Function Measure is valid and sensitive as an outcome measure for clinical trials in pediatric spinal muscular atrophy.

Adolescent↗
PubMed2005

CINRG randomized controlled trial of creatine and glutamine in Duchenne muscular dystrophy.

We tested the efficacy and safety of glutamine (0.6 gm/kg/day) and creatine (5 gm/day) in 50 ambulant boys with Duchenne muscular dystrophy in a 6-month, double-blind, placebo-controlled clinical trial. Drug efficacy was tested by measuring muscle strength manually (34 muscle groups) and quantitatively (10 muscle groups). Timed functional tests, functional parameters, and pulmonary function tests were secondary outcome measures. Although there was no statistically significant effect of either therapy based on manual and quantitative measurements of muscle strength, a disease-modifying effect of creatine in older Duchenne muscular dystrophy and creatine and glutamine in younger Duchenne muscular dystrophy cannot be excluded. Creatine and glutamine were well tolerated.

Child↗
PubMed2004

Heterogeneity of nemaline myopathy cases with skeletal muscle alpha-actin gene mutations.

Nemaline myopathy (NM) is the most common of several congenital myopathies that present with skeletal muscle weakness and hypotonia. It is clinically heterogeneous and the diagnosis is confirmed by identification of nemaline bodies in affected muscles. The skeletal muscle alpha-actin gene (ACTA1) is one of five genes for thin filament proteins identified so far as responsible for different forms of NM. We have screened the ACTA1 gene in a cohort of 109 unrelated patients with NM. Here, we describe clinical and pathological features associated with 29 ACTA1 mutations found in 38 individuals from 28 families. Although ACTA1 mutations cause a remarkably heterogeneous range of phenotypes, they were preferentially associated with severe clinical presentations (p < 0.0001). Most pathogenic ACTA1 mutations were missense changes with two instances of single base pair deletions. Most patients with ACTA1 mutations had no prior family history of neuromuscular disease (24/28). One severe case, caused by compound heterozygous recessive ACTA1 mutations, demonstrated increased alpha-cardiac actin expression, suggesting that cardiac actin might partially compensate for ACTA1 abnormalities in the fetal/neonatal period. This cohort also includes the first instance of an ACTA1 mutation manifesting with adult-onset disease and two pedigrees exhibiting potential incomplete penetrance. Overall, ACTA1 mutations are a common cause of NM, accounting for more than half of severe cases and 26% of all NM cases in this series.

Actinin↗
PubMed2004

Spinal muscular atrophy.

Spinal muscular atrophy is a common genetic disease of the motor neuron (frequency of eight cases per 100,000 live births) with a high mortality during infancy and no known treatment. Death is caused by severe and progressive restrictive lung disease. New information regarding the nature and function of the SMN protein and the availability of new pharmacologic agents now make it possible to consider clinical trials in this disease. Rehabilitation and proper management of medical complications have improved both the quality and duration of life for children with spinal muscular atrophy.

Animals↗
PubMed2003

A phase 1 trial of riluzole in spinal muscular atrophy.

BACKGROUND: Severe spinal muscular atrophy (SMA) (Werdnig-Hoffmann disease, acute SMA, and SMA I) is a disease of the motor neuron characterized by onset before 6 months of age, failure ever to achieve sitting without support, and a life expectancy of 2 years or less. There is no known treatment for SMA, and, until recently, no therapeutic trials have been attempted. There is reason to believe that glutamate, an excitatory neurotransmitter, enhances programmed cell death of anterior horn cells. Riluzole, a glutamate inhibitor, has been shown to slow the rate of decline in patients with amyotrophic lateral sclerosis, another form of motor neuron disease. OBJECTIVES: To determine whether a glutamate inhibitor might be tolerated by infants with SMA and, furthermore, whether this medication could have a positive effect on life expectancy. DESIGN: Subjects with homozygous deletions of the survival motor neuron gene were recruited from pediatric neuromuscular clinics and randomized in a 2:1 ratio, 2 riluzole to 1 placebo. Neurologic examination was performed at the first visit by one of the investigators. Complete blood count, hepatic and renal screens, and urinalysis were performed at baseline, 2 weeks, 1 month, 2 months, 3 months, 6 months, and 9 months after drug or placebo was started. An electrocardiogram was done at baseline, 3 months, 6 months, and 12 months. Treatment was stopped after 9 months, and blood work was repeated at 12 months. Treatment was reinstituted at 1 year if requested by the parents. The enrollment goal was 30 patients; however, support from the pharmaceutical company was withdrawn when Rhone-Poulenc Rorer was taken over by Aventis. The investigational review boards of the participating centers approved the protocol and consent forms. RESULTS: Seven patients received riluzole and 3 received placebo medication. All 3 patients in the placebo group died (mean age, 9 months). Three of 7 who received active drug are still living at ages 513 years, 4 years, and 30 months. None of the 10 subjects experienced adverse effects or changes in laboratory test results. None showed any change in motor abilities. CONCLUSIONS: Riluzole appears to be safe in young children. This was a limited study with insufficient power to show a difference between the 2 groups. Because there is a suggestion of possible benefit in treated subjects, we recommend further study of riluzole in pediatric patients with SMA.

Age of Onset↗
PubMed2003

Reliability of 4 outcome measures in pediatric spinal muscular atrophy.

BACKGROUND: Spinal muscular atrophy is a common neurologic disorder of infants and children with a high mortality rate. Clinical trials have not been attempted in this population until recently. OBJECTIVE: To demonstrate that 4 outcome measures are reliable for use in clinical trials in patients with spinal muscular atrophy. DESIGN, SETTING, PATIENTS: Thirty-eight children with spinal muscular atrophy who fulfilled inclusion and exclusion criteria were enrolled at 5 pediatric centers for a reliability study. Paired samples statistics were performed comparing results of the qualifying variance visit with a fourth visit. MAIN OUTCOME MEASURES: Quantitative muscle testing and the Gross Motor Function Measure. RESULTS: Thirty-four patients and 7 evaluators completed the study. Thirteen patients were aged 2 through 4 years and 21 were 5 through 17 years. The Gross Motor Function Measure was completed by 34 subjects. Six variables for pulmonary function tests were measured in 20 subjects. Quantitative muscle testing was performed on 21 subjects in 8 muscle groups. Thirty-three subjects completed the PedsQL Neuromuscular Module for Parents. The intraclass correlation coefficient and Bradley-Blackwood procedures indicated a very high level of agreement between measures. CONCLUSION: The Gross Motor Function Measure, pulmonary function tests, quantitative muscle testing, and quality of life are reliable outcome measures for clinical trials in pediatric spinal muscular atrophy.

Adolescent↗
PubMed2003

Postoperative malnutrition in Duchenne muscular dystrophy.

Dysphagia and aspiration seem to be rare in Duchenne muscular dystrophy, but cachexia can be associated with early death. Commonly, weight loss can be attributed to inadequate caloric intake caused by loss of ability to self-feed and/or fatigue. Our objective was to determine whether scoliosis repair is associated with malnutrition. A retrospective chart review was undertaken of patients with Duchenne muscular dystrophy, including those who underwent operative repair of scoliosis. We identified nine boys who lost > 5% body weight within 12 months of surgery. Eight patients who gained weight after surgery and eight patients of comparable age who had no surgery served as control subjects. All patients had no change in biceps strength after surgery, but those who lost weight were unable to self-feed. We found that weight loss after surgery was associated with loss of self-feeding. We conclude that pre- and postoperative management of patients with Duchenne muscular dystrophy should include feeding evaluation and determination of postural changes.

Activities of Daily Living↗
PubMed2002

Outcome measures for pediatric spinal muscular atrophy.

BACKGROUND: Spinal muscular atrophy (SMA) is a genetic disease of the anterior horn cell with a frequency of 8 per 100 000 live births and a high rate of mortality during infancy. The American Spinal Muscular Atrophy Randomized Trials (AmSMART) Group is an organization of 5 centers formed to perform clinical trials in children with SMA. OBJECTIVE: To devise reliable methods to measure strength, motor function, lung function, and quality of life for use as outcome measures in children with SMA. SETTING: Tertiary referral center, pediatric neurology department. PATIENTS AND METHODS: Twelve children with SMA aged 2 to 14 years were enrolled in a reliability study of 4 outcome measures: quantitative muscle testing (in children >5 years), gross motor function measure, pulmonary function tests, and quality of life. The Richmond Quantitative Measurement System was used to test grip, knee flexion and extension, and elbow flexion. Gross motor function measure was performed as described, and pulmonary function tests were measured using the KoKo system. Quality of life was assessed via the PedsQL and the PedsQL Neuromuscular Module for patients and parents. RESULTS: Ten children fulfilled the inclusion criteria and completed at least 3 visits with 3 evaluators in 6 months. Using a weighted kappa, the gross motor function measure showed high interrater reliability. Quantitative muscle testing showed greater variability among the weakest children; the findings for pulmonary function tests and quality of life were inconclusive. The PedsQL Neuromuscular Module for parents had moderately high reliability. CONCLUSION: A tool for motor function may be more useful in clinical trials of childhood SMA than one for quantitative muscle strength.

Adolescent↗
PubMed2002

Assessment of cardiac function in adolescents with Duchenne muscular dystrophy: importance of neurohormones.

Initial signs of cardiac dysfunction caused by Duchenne muscular dystrophy are usually detected during adolescence. However, decreased physical activity can allow better tolerance of decreased cardiac function. Mild myocardial dysfunction secondary to ischemic or idiopathic cardiomyopathy is accompanied by elevation of plasma levels of norepinephrine and atrial natriuretic factor. This is considered an adaptation to maintain adequate perfusion. We evaluated neurohormone levels in 17 adolescents (median age 14 years) with Duchenne muscular dystrophy and different degrees of ventricular dysfunction determined by echocardiography. All patients were asymptomatic. Electrocardiographic abnormalities were present in 14 of 17 (82%). Shortening fraction was below normal in 9 of 17 (53%). Norepinephrine plasma levels were elevated in 3, and all had normal atrial natriuretic factor levels. There was no association between fractional shortening and norepinephrine plasma level (P = .66). The majority of younger adolescents with Duchenne muscular dystrophy and abnormal ventricular function do not show signs of inadequate perfusion, as evidenced by normal measurements of neurohormones.

Adolescent↗