PubMed Health⌕ Search

Biomedical subjects

R J Barohn

Publications and source records attributed to R J Barohn.

At least 19 recordsLinked to original sources

Pilot trial of etanercept in the treatment of inclusion-body myositis.

Inclusion-body myositis (IBM) is an inflammatory muscle disease that has proven resistant to treatment. Tumor necrosis factor molecules have been detected in muscle biopsies from patients with IBM. Etanercept is a TNFalpha receptor fusion protein that binds and inactivates tumor necrosis factor. Nine patients were treated with etanercept at a dose of 25 mg, two times a week for an average of 17 +/- 6.1 months. Each patient was evaluated using quantitative strength testing. Their data were compared to two different control groups. The first control group consisted of patients who participated in trials of beta-interferon-1A and had received placebo. There was no significant difference. The second control group was a natural history cohort of IBM patients. There was no statistically significant difference between the treated group and the natural history group at 6 and 12 months when looking at elbow flexors, or 6 months when looking at hand grip. In the treated patients there was a small but significant improvement (p = 0.002) in handgrip at 12 months.

Cohort Studies↗

Bilateral isolated phrenic neuropathy causing painless bilateral diaphragmatic paralysis.

The authors report four patients with a syndrome of painless bilateral isolated phrenic neuropathy. Electrophysiologic testing demonstrated active denervation restricted to the diaphragm. Long-term recovery was poor. The authors conclude that bilateral isolated phrenic neuropathy is a cause of painless diaphragmatic paralysis distinguishable from immune brachial plexus neuropathy and other neuromuscular disorders with similar clinical presentation.

Adult↗

Myopathy with skeletal asymmetry and hemidiaphragm elevation is caused by myotubularin mutations.

The authors report two families with a myopathy phenotype affecting only women, marked by asymmetric weakness, skeletal asymmetry, and an elevated hemidiaphragm. One family had a mutation in a stop codon in exon 9 of the myotubularin gene, and the other had a splice site mutation in exon 13. Both families had manifesting and nonmanifesting carriers. Skewed X-inactivation appeared to explain the clinical manifestations in only one of the two families.

Adult↗

Can we eliminate placebo in ALS clinical trials?

BACKGROUND: Previous studies concluded that the decline in strength in patients with amyotrophic lateral sclerosis (ALS) is a linear function. If so, a patient's natural history might serve as the control, instead of placebo, in a clinical trial. METHODS: A placebo-controlled ALS clinical trial included a natural history phase, followed by a 6-month treatment phase. Each patient's forced vital capacity (FVC) score and maximal voluntary isometric contraction (MVIC) raw scores were measured monthly, standardized, and averaged into megascores. For 138 patients, the arm, leg, FVC, arm+leg combination, and arm+leg+FVC combination megascore slopes during the natural history phase and during the placebo phase were compared. RESULTS: The mean slope of megascores during the natural history phase and the mean slope during the placebo phase were not different for the arm, leg, and arm+leg megascores, but were different for the FVC and arm+leg+FVC combination megascores. CONCLUSIONS: Natural history controls may be useful in ALS exploratory trials that use arm megascore slope as the primary outcome measure. However, there are distinct limitations to the use of natural history controls, so that Phase 3 ALS clinical trials require placebo controls.

Amyotrophic Lateral Sclerosis↗

Axonal multifocal motor neuropathy without conduction block or other features of demyelination.

BACKGROUND: Conduction block is considered an essential finding for the distinction between motor neuropathies and lower motor neuron disorders. Only a small number of reports describe patients with multifocal motor neuropathies who lack overt conduction block, although in these cases other features of demyelination still suggest the presence of a demyelinating disorder. In contrast, a purely axonal multifocal motor neuropathy has not been described. METHODS: This report describes nine patients with slowly or nonprogressive multifocal motor neuropathies who had purely axonal electrodiagnostic features. RESULTS: GM1 antibodies titers were normal in all nine cases. Six patients were treated with either prednisone or IV immunoglobulin and three showed convincing improvement. CONCLUSIONS: These findings suggest an immune-mediated motor neuropathy with axonal electrophysiologic features that appears to be distinct from both multifocal motor neuropathy and established motor neuron disorders.

Adolescent↗

A preliminary evaluation of a prospective study of pulmonary function studies and symptoms of hypoventilation in ALS/MND patients.

There is still no consensus as to which physiologic marker should be used as a trigger for the initiation of non-invasive positive pressure ventilation (NPPV) in patients with amyotrophic lateral sclerosis (ALS). Current practice parameters recommend that the decision to begin treatment be based upon forced vital capacity (FVC) measurements. A prospective, randomized study was performed in 20 ALS patients who had an FVC of 70-100%. Patients received baseline assessments including: ALS functional rating scale-respiratory version (ALSFRS-R), pulmonary symptom scale, Short form 36 (SF-36), FVC%, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and nocturnal oximetry. Patients were randomized to receive NPPV based upon nocturnal oximetry studies suggesting oxygen desaturation <90% for one cumulative minute ("early intervention") or a FVC <50% ("standard of care"). At enrollment, there was no significant correlation between FVC% and the ALSFRS-R, symptom score, MEP, MIP, or duration of nocturnal desaturation <90%. An increase in the vitality subscale of the SF-36 was demonstrated in 5/6 patients randomized to "early intervention" with NPPV. Our data indicate that FVC% correlates poorly with respiratory symptoms and suggests that MIP and nocturnal oximetry may be more sensitive measures of early respiratory insufficiency. In addition, intervention with NPPV earlier than our current standard of care may result in improved quality of life.

Disease Progression↗

Genomic organization of the dysferlin gene and novel mutations in Miyoshi myopathy.

OBJECTIVE: Mutations in the skeletal muscle gene dysferlin cause two autosomal recessive forms of muscular dystrophy: Miyoshi myopathy (MM) and limb girdle muscular dystrophy type 2B (LGMD2B). The purpose of this study was to define the genomic organization of the dysferlin gene and conduct mutational screening and a survey of clinical features in 21 patients with defined molecular defects in the dysferlin gene. METHODS: Genomic organization of the gene was determined by comparing the dysferlin cDNA and genomic sequence in P1-derived artificial chromosomes (PACs) containing the gene. Mutational screening entailed conformational analysis and sequencing of genomic DNA and cDNA. Clinical records of patients with defined dysferlin gene defects were reviewed retrospectively. RESULTS: The dysferlin gene encompasses 55 exons spanning over 150 kb of genomic DNA. Mutational screening revealed nine novel mutations associated with MM. The range of onset in this patient group was narrow with a mean of 19.0 +/- 3.9 years. CONCLUSION: This study confirms that the dysferlin gene is mutated in MM and LGMD2B and extends understanding of the timing of onset of the disease. Knowledge of the genomic organization of the gene will facilitate mutation detection and investigations of the molecular biologic properties of the dysferlin gene.

Adolescent↗

Phase III randomized trial of gabapentin in patients with amyotrophic lateral sclerosis.

BACKGROUND: Preclinical and clinical studies of gabapentin in patients with ALS led the authors to undertake a phase III randomized clinical trial. METHODS: Patients were randomly assigned, in a double-blinded fashion, to receive oral gabapentin 3,600 mg or placebo daily for 9 months. The primary outcome measure was the average rate of decline in isometric arm muscle strength for those with two or more evaluations. RESULTS: Two hundred four patients enrolled, 196 had two or more evaluations, and 128 patients completed the study. The mean rate of decline of the arm muscle strength was not significantly different between the groups. Moreover, there was no beneficial effect upon the rate of decline of other secondary measures (vital capacity, survival, ALS functional rating scale, timed walking) nor was there any symptomatic benefit. In fact, analysis of the combined data from the phase II and III trials revealed a significantly more rapid decline of forced vital capacity in patients treated with gabapentin. CONCLUSION: These data provide no evidence of a beneficial effect of gabapentin on disease progression or symptoms in patients with ALS.

Acetates↗

Randomized controlled trial of IVIg in untreated chronic inflammatory demyelinating polyradiculoneuropathy.

OBJECTIVE: To determine the efficacy of IV immunoglobulin (IVIg) given patients with untreated chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). METHODS: A randomized, double-blind, multicenter, investigator-initiated study compared IVIg (Aventis Behring LLC, King of Prussia, PA) with placebo (5% albumin). On days 1, 2, and 21, IVIg (1 g/kg) or placebo was given. The primary outcome measure was the change in muscle strength from baseline to day 42, using the average muscle score (AMS). Secondary outcome measures included change from baseline AMS at days 10 and 21, the Hughes' functional disability scale, forced vital capacity (FVC), and nerve conduction studies (NCS) of four motor nerves (median, ulnar, peroneal, and tibial). RESULTS: The patients (n = 33) were randomized. Of these, 30 (14 women, 16 men, aged 54 +/- 20 years, range 13 to 82) received IVIg and 23 were given placebo (12 women, 11 men, aged 50 +/- 18 years, range 23 to 73). Baseline AMS values of the groups were similar (IVIg 7.06 +/- 1.31 versus placebo 7.28 +/- 1.18, p = 0.53). There were two dropouts in placebo group and one in the IVIg group. Mean AMS improved at day 42 comparing IVIg with placebo (0.63 versus -0.1, p = 0.006). Improved strength was seen by day 10. The placebo group lost strength over this same interval. In the IVIg, 11 subjects improved by the functional disability scale; none worsened. This differed (p = 0.019) from those in the placebo-treated group (two improved, two got worse, remainder unchanged). Forced vital capacity did not improve with IVIg treatment. IVIg improved ulnar motor distal latency (p = 0.005), tibial distal compound muscle amplitude (p = 0.003), and peroneal nerve conduction velocity (p = 0.03). CONCLUSIONS: IVIg improves strength in patients with untreated CIDP by day 10 with continued benefit through day 42; more than one third improve by at least a functional grade on a disability scale. This study provides data supporting IVIg as the initial treatment for CIDP.

Adolescent↗

Clinical spectrum of chronic acquired demyelinating polyneuropathies.

A number of presentations of chronic demyelinating polyneuropathy have been identified, each distinguished by its phenotypic pattern. In addition to classic chronic inflammatory demyelinating polyneuropathy (CIDP), which is characterized clinically by symmetric proximal and distal weakness and sensory loss, several regional variants can be recognized: multifocal motor neuropathy (MMN: asymmetric and pure motor), multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy (asymmetric, sensory, and motor), and distal acquired demyelinating symmetric (DADS) neuropathy (symmetric, distal, sensory, and motor). There are also temporal, pathological, and disease-associated variants. This review describes a clinical scheme for approaching the chronic acquired demyelinating polyneuropathies that leads to a rational use of supportive laboratory studies and treatment options. In addition, we propose new diagnostic criteria for CIDP that more accurately reflect current clinical practice.

Humans↗

Cervicobrachial involvement in diabetic radiculoplexopathy.

Diabetic radiculoplexopathy is commonly viewed as a condition affecting the lower extremities. However, other regions may also be affected and the presence of upper extremity involvement has rarely been emphasized. Our goal was to illustrate the clinical features of arm involvement in this condition. Of 60 patients with diabetic lumbosacral radiculoplexopathy, we identified 9 who also had upper extremity involvement. The study included 8 men and 1 woman, ranging in age from 36 to 71 years. Upper limb involvement developed simultaneously with the onset of lower limb disorder in 1 patient, preceded it by 2 months in another patient, and occurred between 3 weeks and 15 months later in the remaining 7. In 5 cases, arm involvement developed after symptoms in the legs began to improve. The upper extremity weakness affected the hands and forearms most severely. It was unilateral in 5 patients and bilateral but asymmetric in 4. Pain was often present, but it was not a prominent feature. In most patients, neurologic deficits in the arms improved spontaneously after 2-9 months. We conclude that diabetic radiculoplexopathy may involve the cervical region before, after, or simultaneously with the lumbosacral syndrome. The upper limb process is similar to that in the legs, with subacutely progressive weakness and pain followed by spontaneous recovery.

Adult↗

Clinical and genetic aspects of distal myopathies.

Although most muscle disorders produce proximal weakness, some myopathies may manifest predominantly or exclusively distal weakness. Although several congenital, inflammatory, or metabolic myopathies may produce mainly distal weakness, there are several distinct entities, typically referred to as distal myopathies. Most of these are inherited conditions. The distal myopathies are rare, but characteristic clinical and histological features aid in their identification. Advances in molecular genetics have led to the identification of the gene lesions responsible for several of these entities and have also expanded our understanding of the genetic relationships of distal myopathies to other inherited disorders of muscle. This review summarizes current knowledge of the clinical and molecular aspects of the distal myopathies.

Adult↗

Update on the evaluation and therapy of autoimmune neuromuscular junction disorders.

Many recent strides have increased our understanding of the immune-mediated diseases of neuromuscular junction transmission. Nevertheless, patients with myasthenia gravis and the Lambert-Eaton myasthenic syndrome often present diagnostic and therapeutic challenges to clinicians. Both conditions have a wide range of clinical presentations and the number of treatment modalities available to these patients continues to increase. This creates a need for an individualized approach for managing these patients. Other important controversies exist because the benefits of some treatments are not firmly established by clinical trials. After a brief review of the pertinent scientific basis of these diseases, we focus on present issues governing the clinical evaluation and management of myasthenia gravis and the Lambert-Eaton myasthenic syndrome.

Autoimmune Diseases↗

Superficial peroneal nerve/peroneus brevis muscle biopsy in vasculitic neuropathy.

OBJECTIVE: To determine the sensitivity and specificity of superficial peroneal nerve (SPN)/peroneus brevis muscle (PBM) biopsy in a cohort of patients with suspected peripheral nerve vasculitis. BACKGROUND: In patients with suspected vasculitic neuropathy, combined nerve and muscle biopsies have been advocated as a way to increase the diagnostic yield, but the sensitivity and specificity of this approach have not been evaluated. Pathologic predictors of biopsy-proven peripheral nerve vasculitis have also not been analyzed in a systematic fashion. METHODS: The clinical, laboratory, and pathologic data for all patients undergoing SPN/PBM biopsy for possible vasculitis from 1986 through 1996 were analyzed. Biopsies were classified as positive, negative, or suspicious for vasculitis. Patients were then divided into vasculitis and nonvasculitis cohorts by final clinical diagnosis. RESULTS: Of 70 SPN/PBM biopsies, 22 (30%) showed definite vasculitis; nerve was diagnostic in 90% (n = 20) and muscle in 50% (n = 11). Nerve biopsy had a higher yield than muscle in patients with nonsystemic vasculitic neuropathy (p = 0. 0047) but not in those with systemic vasculitis. The estimated sensitivity of a positive SPN/PBM biopsy for vasculitis was 60%. Considering biopsies either positive or suspicious for vasculitis increased the sensitivity to 86% with a corresponding specificity of 85%. Pathologic features associated with necrotizing vasculitis were muscle fiber necrosis/regeneration (relative risk 18.1; 95% CI 3.4 to 96.1), predominant axonal nerve pathology (>8.8; >1.0 to 77.4), Wallerian-like degeneration (5.6; 1.4 to 21.9), and asymmetric nerve fiber loss (4.6; 1.4 to 15.9). CONCLUSIONS: These findings establish the yield, sensitivity, and specificity of SPN/PBM biopsy for diagnosing vasculitic neuropathy and validate the use of suggestive pathologic features for diagnosing cases lacking definite necrotizing vascular changes.

Aged↗