Chronic distal spinal amyotrophy localized to the both upper limbs (O'Sullivan and McLeod type)

A case of sporadic spinal muscular atrophy affecting the upper limbs and with a chronic course over 19 years is reported, features of the affection being similar to the rare cases reported in the literature. Distinguishing aspects of these cases are those of a particular topographical form of chronic spinal muscular atrophies: onset in adolescents or young adults, symmetrical weakness and atrophy of the small muscles of the hands sometimes extending to the forearms, a progressive and slow course, absence of sensory or pyramidal signs, normal findings on cervical cord examinations neurogenic electromyogram recordings and normal nerve conduction rates.     

Oculopharyngeal involvement in familial neurogenic muscular atrophy

A Japanese family with progressive spinal muscular atrophy is presented. Seven members in two generations were affected and the mode of inheritance was probably an autosomal recessive trait. A characteristic feature of this family was the presence of oculopharyngeal involvement in some of the affected members, in addition to the variable distribution of muscular atrophy among each of the affected members, such as mainly proximal or distal atrophies in the limbs. In one case the oculopharyngeal weakness appeared without limb involvement. The changes in the extremities were thought to be of neurogenic origin, and so was the progressive external ophthalmoplegia seen characteristically in these cases, although the latter was similar to ocular myopathy.     

Lipid peroxidation and superoxide dismutase activity in muscle and erythrocytes in adult muscular dystrophies and neurogenic atrophies

Summary Lipid peroxidation (LP) and superoxide dismutase (SOD) activity were determined in erythrocytes and skeletal muscle obtained from patients with limb-girdle and facioscapulohumeral muscular dystrophies, neurogenic atrophies and from age-matched control subjects. Neither lipid peroxidation nor SOD activity in erythrocytes of patients differed from control values. SOD activity and LP in muscle specimens were also normal in types of neurogenic atrophy. Lipid peroxidation in the muscle from patients with adult types of muscular dystrophy had a tendency to be increased. The values were widely scattered, the highest being obtained in the older patients with long duration of disease.     

Limb girdle syndromes. Clinical, morphological and electrophysiological studies

The clinical syndrome of slowly progressive proximal limb and limb girdle muscular weakness and atrophy, or limb girdle syndromes (LGS), has a diverse aetiology. Several of the congenital, mitochondrial and other metabolic myopathies and spinal muscular atrophies are recently recognized causes of LGS. Thus the position of limb girdle muscular dystrophy (LGMD) as a discrete entity in the nosology of muscle disease deserves reappraisal. We have therefore reevaluated our experience of 33 patients in this light. Detailed clinical, electrophysiological, and pathological studies including autopsies in 2 cases, were performed. As a result we are confident that LGMD does exist as a sporadic or autosomal dominant (2 families) or recessive condition (2 families). There are therefore probably at least 2 distinct genotypes. Typical LGMD (18 patients in our series) is characterized by slowly progressive symmetrical proximal upper and lower limb girdle weakness and atrophy, elevation of the serum creatine kinase at some stage, dystrophic or less severe myopathic muscle lesions on biopsy, and myopathic EMG findings. Two minor subgroups of LGMD were identified in our series with similar clinical and laboratory features but distinguishable by the development of either facial (4 patients) or by distal limb muscle involvement (3 patients). A further group of patients with sporadic LGS (5 patients) had slowly progressive proximal symmetrical upper and lower limb-girdle weakness and atrophy with myopathic or neurogenic features on either EMG or muscle biopsy so that the precise characterization was difficult. Two of these patients had distal limb muscle involvement and contractures. One patient had upper limb-girdle muscle atrophy with normal lower limbs. A disorder affecting muscle, nerve or both remains a possibility in these cases.     

Skeletal muscle CK-B activity in neurogenic muscular atrophies

Summary Creatine kinase isoenzymes were determined in skeletal muscle biopsy specimens of 34 patients suffering from neurogenic muscular atrophies. The findings were compared: (1) with those of 38 control muscle samples and (2) with those in 41 muscular dystrophies and other myopathic conditions. The measurements were made by electrophoretic separation and elution of the isoenzymes and by immunoinhibition assay. The results showed that the total and specific CK activity were significantly decreased (P<0.005) in neurogenic atrophies in contrast to myopathic conditions where no differences from control levels were observed. This decrease was due to a decrease of the CK-M subunit activity, while the CK-B subunit was elevated. The muscle CK-MB activity was considerably elevated in muscular dystrophies (P<0.02) and myositis (P<0.001), but it was also slightly elevated in neurogenic conditions. The similarity of the muscle CK isoenzyme pattern in neurogenic atrophies and myotonic dystrophy was noted. These findings could possibly reflect considerable difference in the regeneration process of neurogenic atrophies and muscular dystrophies.     

Neurogenic muscle involvement in myasthenia gravis: A clinical and histopathological study

An investigation was made into the occurrence of muscular atrophy and muscular pathology in a series of 170 patients with myasthenia gravis. The results can be summarized as follows: (1) Of the 148 patients with generalized myasthenia gravis, 14 showed local muscular atrophies. Of 10 biopsies from atrophic muscles, eight showed neurogenic changes, with or without lymphocytic infiltrations. One biopsy showed lymphocytic infiltrations only, and one showed type II-fibre atrophy (Table 1). No relationship was demonstrable between the presence of clilnical muscular atrophy and age, sex, duration of the disease, severity of the disease, presence of a thymoma, or drug resistant ophthalmoplegia. (2) In this group of patients 61 biopsies were examined from 46 individuals; 40 of these biopsies were taken from the quadriceps muscle. A thymoma was present in 17 patients. Examination disclosed neurogenic changes in 17 biopsies, lymphocytic infiltrates in 21, and myositis in one biopsy (Table 2). A distinct correlation was established between the presence of a thymoma and lymphocytic infiltrates, but none was demonstrable between thymoma and neurogenic changes (Table 3). (3) An enzyme-histochemical study was carried out in 35 cases, including 12 with neurogenic changes. A normal differentiation of type I- and type II-fibres was observed in eight instances, type grouping of type II-fibres in three, and type II-fibre atrophy in two cases. (4) In 21 patients and 19 controls, the smallest mean diameter was determined in the quadriceps muscle. Both type I- and type II-fibres proved to have a smaller mean diameter in the female patients than in the controls. In the male patients this could not be proven. (5) Of the eight patients who had died without disorders of ventilation, 90 muscle specimens were examined postmortem. Four of these patients had a thymoma. Lymphocytic infiltrations, found in 32 biopsy specimens, were mostly observed in the presence of a thymoma. Neurogenic changes were apparently unrelated to the presence of a thymoma (Tables 5 and 6). The post mortem examination included the spinal cord in five, and peripheral nerves in three cases. No abnormalities were found. (6) The muscular atrophy found in patients with myasthenia is not a myopathy but an affection of the lower motor neurone. Neurogenic changes were regularly found in the muscles of patients with myasthenia, even without muscular atrophy. The finding of these changes is no reason to reject the diagnosis. It is postulated that denervation occurs at the neuromuscular junction as a result of permanent absence of acetylcholine.     

Investigations on enzyme activity in the serum and CSF of patients with neuromuscular diseases

Summary The CPK, aldolase, GOT, GPT, and LDH concentrations in the serum and lumbar CSF of 80 patients with neuromuscular diseases and 20 controls were measured. The value obtained in serum were essentially in agreement with the data in the literature. This is the first publication reporting on regular CSF enzyme examinations in different neuromuscular disorders, particularly the results obtained in neurogenic muscular atrophies, which have certain characteristic features. The LDH activity in CSF was decreased in peroneal muscular atrophy, the GPT concentration in CSF was elevated in spinal muscular atrophy, and the mean activity of CSF aldolase was increased in amyotrophic lateral sclerosis. The simultaneous determination of enzymes in serum and CSF can provide valuable information in the research of certain details of pathomechanisms and thus lead to further improvement of diagnosis.     

Preferential distal muscle involvement in case of oculopharyngeal muscular dystrophy with (GCG) 13 expansion]

We reported a 52-year-old woman with oculopharyngeal muscular dystrophy (OPMD) harboring expanded (GCG) 13 mutation of the poly (A) binding protein 2 gene. She presented not only ptosis and dysphagia but distal dominant muscle atrophy in four extremities. CT demonstrated distal muscle atrophy with marked fat replacement in the biceps femoris, semitendinosus, membraneous, soleus, and gastrocnemius muscles. Although OPMD is considered to be a muscle disease, this patient showed even neurogenic features in the electrophysiological and pathological findings. Although previous reports indicate that OPMD is genetically homogeneous disease, some cases with OPMD may show some atypical features associated with neurogenic involvement.     

Severe spinal muscular atrophy variant associated with congenital bone fractures

Infantile autosomal recessive spinal muscular atrophy (type I) represents a lethal disorder leading to progressive symmetric muscular atrophy of limb and trunk muscles. Ninety-six percent cases of spinal muscular atrophy type I are caused by deletions or mutations in the survival motoneuron gene (SMNI) on chromosome 5q11.2-13.3. However, a number of chromosome 5q-negative patients with additional clinical features (respiratory distress, cerebellar hypoplasia) have been designated in the literature as infantile spinal muscular atrophy plus forms. In addition, the combination of severe spinal muscular atrophy and neurogenic arthrogryposis has been described. We present clinical, molecular, and autopsy findings of a newborn boy presenting with generalized muscular atrophy in combination with congenital bone fractures and extremely thin ribs but without contractures.     

Phenotypic variability in siblings with type III spinal muscular atrophy

Autosomal recessive spinal muscular atrophy (SMA) shows substantial phenotypic variability, presenting at a variety of ages from infancy to adult life. Diagnostic difficulties may arise because SMA sometimes produces a dystrophic or myopathic phenotype rather than classical neurogenic abnormalities. Two brothers are described who illustrate this principle and highlight the increasing importance of molecular genetics in investigating patients with neuromuscular diseases. The findings are discussed in the light of recent observations in a mouse model of SMA.     

Phosphomannosyl receptors of lysosomal enzymes of skeletal muscle in neuromuscular diseases

The phosphomannosyl receptor system is responsible for both the receptor-mediated endocytosis and the intracellular transport of lysosomal enzymes. In the present study this receptor system was examined in affected muscles of patients with various neuromuscular diseases. The total activity of beta-N-acetyl-glucosaminidase, a marker enzyme of lysosomal hydrolases, was significantly elevated in the patients with myopathies (polymyositis and muscular dystrophies) but only slightly increased in those with neurogenic muscle atrophies (amyotrophic lateral sclerosis, polyneuropathy or other neurogenic muscle disease). The increase was most prominent in the group of polymyositis. The content of phosphomannosyl receptors was increased in the patients with myogenic muscle disease but not in those with neurogenic disease. The receptor binding of lysosomal enzymes was saturable and inhibited with mannose 6-phosphate showing the typical characteristics of phosphomannosyl receptors. The characteristics of the receptors were very similar both to control and to diseased muscle samples. When surveying all the material, the content of phosphomannosyl receptors correlated highly significantly with the muscular activity of beta-N-acetylglucosaminidase, muscle atrophy index, and serum creatine kinase activity.     

A predominantly cervical form of spinal muscular atrophy.

Clinical heterogeneity within the group of spinal muscular atrophies (SMA) in children can pose practical problems of diagnosis, prognosis and genetic counselling. In addition to the classic forms, unusual cases have been described. Five children with an atypical type of SMA are reported, characterised by early involvement of cervical muscles contrasting with initially mild or absent affection of peripheral muscles. Secondary involvement of respiratory muscles was responsible for the death of three children in the second to fourth year. The disorder may be recessively inherited.     

Possible neurogenic factor in muscular dystrophy: its similarity to denervation atrophy

Muscle biopsy specimens from 179 cases of muscular dystrophies and from 140 cases of anterior horn cell disorders (from a total of 1,348 biopsied patients) were examined histologically. There were 72 cases of Duchenne type muscular dystrophy (DMD), five of Becker type MD, four girls with myopathy resembling DMD, 40 with limb-girdle, 10 with facioscapulohumeral, seven with late onset, 13 with congenital, and 28 with unclassifiable muscular dystrophies. Groups of small atrophied muscle fibres were encountered in 42 (23%) of the cases in this group, most frequently in patients with limb-girdle, facioscapulohumeral, and least frequently with DM dystrophy. In the second group there were 25 cases of infantile, 38 of juvenile, and 39 of adult spinal muscular atrophy (SMA); there were 21 patients with motor neurone disease (MND), six with poliomyelitis, and 11 with an unclassifiable type of anterior horn cell disorder. Pseudomyopathic changes were encountered in 43 (30%) of all cases in this group. They were most frequently present among patients with juvenile and adult SMA and in those with MND. The presence of group atrophy in muscular dystrophy is considered significant myopathological evidence of a denervation process. On the other hand, pseudomyopathic changes, variation in fibre size, rounding, central nuclei, and increase in connective tissue occurring in various anterior horn cell disorders are seen not to be specific `myopathic'' changes. Thus there was an overlap of pathological reactions in muscles from the dystrophies and the neurogenic atrophies. Comparably atrophied fibres (much less than 2 SDs below the normal mean diameter) and hypertrophied fibres (much more than 2 SDs above the normal mean diameter) were encountered in both dystrophy and neurogenic atrophy, considering the large muscles of the limb. Likewise, the mean fibre diameters were comparable in DMD and in juvenile SMA. The fourth evidence of a neurogenic factor in muscular dystrophy was derived from an examination of SDH preparations of muscle. There was a preponderance of type I muscle fibres in dystrophic muscles compared with specimens from controls, suggesting depletion of type II fibres. It appears that the concept of muscular dystrophy as a primary muscle disease needs to be re-examined.     

Hereditary motor neuropathy, distal type: electrophysiological and pathological studies of a case

A case of HMN, distal type transmitted as autosomal dominant is described. Clinical findings appear to be consistent with a peroneal muscular atrophy, indistinguishable from HMSN types I and II. The electrophysiological data reveal a pathological involvement of the anterior horns, whereas sensory and motor conduction are normal. A muscle biopsy showed neurogenic atrophy, while the morphology of the sural nerve was normal.

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Sommario Viene presentato un caso di HMN distal type trasmesso in modo autosomico dominante. La clinica appare essere quella di una atrofia muscolare peroneale indistinguibile da quella tipo HMSN I e II. I dati elettrofisiologici indicano la presenza di sofferenza delle corna anteriori mentre normale risulta essere la conduzione sia sensitiva che motoria. La biopsia muscolare mostra atrofia neurogena mentre normale appare la morfologia del nervo surale. Si discute il caso alla luce della letteratura.

     

THE DEVELOPMENT OF THE EXTENSOR DIGITORUM BREVIS MUSCLE IN PROGRESSIVE PROXIMAL MUSCULAR ATROPHIES

The development of the extensor digitorum brevis (EDB) muscle was studied in 39 healthy subjects, 27 patients with progressive proximal spinal muscular atrophy, 20 patients with limb-girdle muscular dystrophy and three with facioscapulohumeral muscular dystrophy. The EDB muscle is spared and usually hypertrophic in patients with muscular dystrophy, whereas it is often atrophic and weak in patients with spinal muscular atrophy. It is proposed that the degree of development of the EDB muscle can be used as a clinical sign in the differential diagnosis of progressive muscular atrophies.     

Role of the electrophysiologic examination in the diagnosis of Bassen-Kornzweig syndrome

An autosomal recessive disorder, abetalipoproteinemia or Bassen-Kornzweig disease, concerning two sisters are described. This disorder, clinically similar to Friedreich ataxia, should be examined by electrophysiological and laboratory procedures because of the possibility of treatment by high doses of vitamin A and E. The routine electrophysiological examination of the two sisters revealed a degenerative spinocerebellar and peripheral nervous process which confirmed the damage of large myelinated fibers, as reported in the literature: neurogenic muscular atrophy of distal muscles, polyphasic motor unit potentials, moderately decrease of lower motor and sensory nerve conduction rates, and reduced amplitude of evoked responses in sensory nerves and muscles. We stress out the diagnostic value of the heterogenous conduction decrease in the distal motor fibers, signs of processes of demyelination or distal regeneration.     

慢性脊髓性肌萎缩症的临床和肌活检

文章报道２４例慢性脊髓性肌萎缩症，其中婴儿型、少年型、成年型慢性近端型分别为５例、２例及１３例，面肩肱型２例，远端型和肩腓型各１例。本病主要临床表现为肌无力、肌萎缩和不同程度的肌束震颤，锥体束和周围神经一般不受累。各型肌萎缩的部位不同。３例患者伴有ＣＰＫ浓度增高。除２例肌电图正常外，其余表现为失神经性改变。光镜提示神经原性萎缩。电镜下见肌原纤维数量减少，Ｚ线变粗或波浪状以及线粒体和内质网肿胀。     

Clinical forms of inclusion body myositis: 12 cases

Inclusion body myositis is now a well-known disease but its incidence is underestimated. We report 12 cases with clinical heterogeneity. Three groups of patients could be described. The first one corresponded to asymmetrical muscle involvement and distribution with a slow clinical course (4 cases). The second was characterized by a polymyositis-like syndrome (3 cas), but steroid therapy was ineffective. The last group mimicked a chronic spinal muscular atrophy (4 cases). One patient showed a scapuloperoneal syndrome. Both myopathic and neurogenic EMG patterns were present in 6 patients; a neurogenic pattern was found in 4 cases and a myopathic pattern in 2 cases. In all patients, muscle biopsies showed rimmed vacuoles with eosinophilic inclusions. In 9 cases ultrastructural studies displayed abnormal filaments of 15-18 nm in diameter in the vacuoles. Intranuclear filaments were rarely observed. The significance of the filaments is unknown and their specificity is doubtful because they are present in other myopathies with rimmed vacuoles (some distal myopathies and oculopharyngeal muscular dystrophies). Finally a rich inflammatory exudate was present in 8 patients only.     

A case of adult-onset nemaline myopathy (adult-onset rod disease) with distal muscular hypertrophy]

We reported a 40-year-old male with adult-onset nemaline myopathy (adult-onset rod disease) showing muscular hypertrophy of distal limbs. At the age of 25, he noticed thinness of his thighs. Difficulty in climbing stairs slowly progressed from the age of 35. On admission neurological examination revealed muscular weakness and atrophy of proximal limbs and hypertrophy of distal flexors. Normal laboratory tests included serum creatine kinase, myoglobin, aldolase and pyruvate. Electromyography revealed severe neurogenic changes in the right biceps brachial muscle and the right quadriceps muscle, and moderate changes in the right gastrocnemius. Biopsy specimen of the deltoid muscle demonstrated type 1 fiber predominance and type 1 fiber atrophy, and there was small group atrophy and type grouping. Abundant nemaline rods were found mainly in type 1 fibers (81.5%). In order to evaluate hypertrophy of calf muscles, T1-weighted MRI of lower extremity was performed. While transaxial images through mid thigh showed moderate fatty replacement, increased volume and little fatty replacement were found in the mid calf. Therefore, hypertrophy of the calf muscle seemed to be compensative hypertrophy. But in this case neurogenic factors were indicated electromyographically and histologically. These findings may advocate the notion that neurogenic factors involved not only congenital but adult-onset rod disease.     

NCAM, vimentin and neonatal myosin heavy chain expression in human muscle diseases

The intermediate filament protein vimentin, the neonatal isoform of the myosin heavy chain gene (MHCn), and the neural cell adhesion molecule (NCAM) are developmentally and/or neurally regulated molecules that reappear transiently after the induction of necrosis, or denervation. Immunostaining using antibodies against these molecules helps to identify regenerating and/or denervated muscle fibres even if they are not recognized by conventional staining procedures. This study examined the expression of vimentin, MHCn, and NCAM using immunohistochemistry in 82 biopsy specimens from muscular dystrophies, inflammatory myopathies, and neurogenic atrophies. Anti-vimentin labelled significantly more fibres than anti-MHCn staining in the inflammatory myopathies (P<0.03) but not in the muscular dystrophies (P=0.58) and neurogenic atrophies (P=0. 58). The fraction of NCAM+ fibres was always more elevated than vimentin+ or MHCn+ fibres. In the necrotizing myopathies, most NCAM+ fibres were regenerating ones (co-expressing vimentin). In neurogenic atrophies, half the NCAM+ fibres were regenerating and half of them were NCAM+/vimentin- and thus were considered to be denervated. Taken together, anti-vimentin staining detects a broader spectrum of regenerating fibres than anti-MHCn, at least in the inflammatory myopathies. The number of anti-NCAM labelled fibres in the necrotizing myopathies is similar, but not identical, to the number of regenerating fibres. Co-staining with anti-vimentin (or anti-MHCn) and anti-NCAM identifies a subset of fibres that is considered to be denervated.