Dystrophic Myopathy of the Diaphragm with Recurrent Severe Respiratory Failure is Congenital Myasthenic Syndrome 11.

We here present the case of a patient with a congenital myasthenic syndrome (CMS) due to pathogenic variants in the RAPSN gene. During childhood he experienced recurrent episodes of respiratory failure during respiratory infections. This and other cases were reported as isolated dystrophy of the diaphragmatic musculature.

Impaired oxygen utilization in skeletal muscle of CRPS I patients.

Background: The purpose of this study was to evaluate oxygen extraction and utilization in end stage chronic complex regional pain syndrome type I (CRPS I) patients undergoing amputation and to relate these to muscle histology of the amputated limb.

Materials And Methods: In 25 patients with severe CRPS I requiring amputation of the affected limb venous blood samples and in 11 patients skeletal muscle specimens were analyzed.

Results: The mean venous oxygen saturation (S(v)O(2)) value (94.

The oxidative response in the chronic constriction injury model of neuropathic pain.

Background: In the chronic constriction injury model of rat neuropathic pain, oxidative stress as well as antioxidants superoxide dismutase and reduced glutathione (GSH) are important determinants of neuropathological and behavioral consequences. Studies of the chronic constriction injury model observed (indirect) signs of inflammation. We, therefore, investigated the level of oxidative stress and antioxidant enzymes in skeletal muscle tissue of the rat hind paw and (jugular vein) plasma at d 7 after nerve injury.

Muscle 3243A-->G mutation load and capacity of the mitochondrial energy-generating system.

Objective: The mitochondrial energy-generating system (MEGS) encompasses the mitochondrial enzymatic reactions from oxidation of pyruvate to the export of adenosine triphosphate. It is investigated in intact muscle mitochondria by measuring the pyruvate oxidation and adenosine triphosphate production rates, which we refer to as the "MEGS capacity." Currently, little is known about MEGS pathology in patients with mutations in the mitochondrial DNA.

Severe congenital muscular dystrophy in a LAMA2-mutated case.

Clinical features and molecular data are described for a patient with undetectable expression of laminin alpha2 chain (merosin) and severe congenital muscular dystrophy. Molecular analysis of the LAMA2 gene revealed two previously un-described mutations. The patient achieved independent sitting at age 2, but lost head balance at age 7; he was never able to stand unsupported.

Null mutations and lethal congenital form of glycogen storage disease type IV.

Glycogen branching enzyme deficiency (glycogen storage disease type IV, GSD-IV) is a rare autosomal recessive disorder of the glycogen synthesis with high mortality. Two female newborns showed severe hypotonia at birth and both died of cardiorespiratory failure, at 4 and 12 weeks, respectively. In both patients, muscle biopsies showed deposits of PAS-positive diastase-resistant material and biochemical analysis in cultured fibroblasts showed markedly reduced glycogen branching enzyme activity.

Early diagnosis of ALS: the search for signs of denervation in clinically normal muscles.

Aim And Methods: We prospectively investigated whether early diagnosis of amyotrophic lateral sclerosis (ALS) could be facilitated by demonstrating signs of denervation in a muscle of a clinical and electromyographical unaffected region. Muscle fibre conduction velocity (MFCV) was determined in 18 patients in whom the diagnosis ALS was considered but not established beyond a level of clinically possible ALS according to the revised El Escorial criteria. A muscle biopsy was obtained from the same muscle, to demonstrate neurogenic changes.

Multiple oxidative phosphorylation deficiencies in severe childhood multi-system disorders due to polymerase gamma (POLG1) mutations.

Failure to thrive, feeding difficulties, variable forms of infantile epilepsy or psychomotor developmental delay and hypotonia were the most frequent clinical disease presentations in eight children with combined oxidative phosphorylation enzyme complex deficiencies carrying mutations in the polymerase gamma (POLG1) gene. Five out of eight patients developed severe liver dysfunction during the course of the disease. Three of these patients fulfilled the disease criteria for Alpers syndrome.

A case of neuromuscular mimicry.

Recognizing an ALS-mimic can be challenging. Here, we describe a patient with a slowly progressive dysarthria and dysphagia, with fasciculations of the tongue and general hyperreflexia, fulfilling the diagnostic criteria of 'clinical probable ALS'. Because of a non-conclusive EMG, a muscle biopsy was performed that surprisingly showed widespread nemaline rods.

Secondary mitochondrial dysfunction in propionic aciduria: a pathogenic role for endogenous mitochondrial toxins.

Mitochondrial dysfunction during acute metabolic crises is considered an important pathomechanism in inherited disorders of propionate metabolism, i.e. propionic and methylmalonic acidurias.

Congenital hypertrophic cardiomyopathy, cataract, mitochondrial myopathy and defective oxidative phosphorylation in two siblings with Sengers-like syndrome.

Unlabelled: We describe two siblings with a Sengers-like syndrome, who presented with congenital hypertrophic cardiomyopathy, infantile cataract, mitochondrial myopathy, lactic acidosis and normal mental development. A mitochondrial adenine nucleotide translocator 1 (ANT1) defect was detected since the ANT1 protein was not detectable by immmunoblotting in muscle samples of the patients. Additionally to these features of classical Sengers syndrome (OMIM 212350), we found that the mitochondrial oxidative phosphorylation, measured by biochemical analysis, was severely compromised in skeletal muscle in both children.

Novel mutations in three patients with LGMD2C with phenotypic differences.

Limb-girdle muscular dystrophy type 2C is an autosomal-recessive disorder caused by mutations in gamma-sarcoglycan encoding gene. This disease is characterized by childhood onset of progressive muscular dystrophy. Because of the clinical presentation, this disorder may be misdiagnosed as a dystrophinopathy.

Investigation of a family following fulminant malignant hyperthermia.

Unlabelled: Malignant hyperthermia (MH) is a pharmacogenetic neuromuscular disorder triggered by inhalational anesthetics or succinylcholine. We studied in detail 24 relatives of a patient who died after experiencing MH. All steps of the screening procedure follow developments in testing for the diagnosis of MH susceptibility from 1984 until 2002.

Muscle-fiber conduction velocity and electromyography as diagnostic tools in patients with suspected inflammatory myopathy: a prospective study.

Combinations of different techniques can increase the diagnostic yield from neurophysiological examination of muscle. In 25 patients with suspected inflammatory myopathy, we prospectively performed needle electromyography (EMG) and measured muscle-fiber conduction velocity (MFCV) in a single muscle, using a technique with direct muscle-fiber stimulation and recording. Results of MFCV were compared with final diagnosis, EMG, and needle muscle biopsy.

Concomitant dermatomyositis and myasthenia gravis presenting with respiratory insufficiency.

We report a 28-year-old woman with a history of chronic immune-mediated hepatitis, in whom the simultaneous manifestation of dermatomyositis and myasthenia gravis resulted in severe neck extensor weakness and subacute respiratory insufficiency, followed by proximal muscle weakness and external ophthalmoplegia. Radiological signs of a thymoma were absent. The distinguishing clinical, electrophysiological, and biopsy findings are discussed.