Congenital muscular dystrophy associated with calf hypertrophy, microcephaly and severe mental retardation in three Italian families: evidence for a novel CMD syndrome

We describe four Italian patients (aged 3, 4, 12, and 13 years ) affected by a novel autosomal form of recessive congenital muscular dystrophy. These patients were from three non-consanguineous families and presented an almost identical phenotype. This was characterized by hypotonia at birth, joint contractures associated with severe psychomotor retardation, absent speech, inability to walk and almost no interest in their surroundings. In addition, all patients had a striking enlargement of the calf and quadriceps muscles. Ophthalmologic examination revealed no structural ocular abnormalities in any of the children; one patient had severe myopia. In all cases a magnetic resonance imaging of the brain showed an abnormal posterior cranial fossa with enlargement of the cisterna magna and variable hypoplasia of the vermis of the cerebellum. Abnormality of the white matter was also present in all patients, in the form of patchy signal most evident in the periventricular areas. Serum CK was grossly elevated in all. The muscle biopsy from all cases showed dystrophic changes compatible with congenital muscular dystrophy. Immunofluorescence studies showed mild to moderate partial deficiency of laminin 2 chain. Linkage analysis in the only informative family excluded the known loci for congenital muscular dystrophy, including laminin 2 chain on chromosome 6q2, the Fukuyama congenital muscular dystrophy locus on 9q3 and the muscle-eye-brain disease on chromosome 1p3. We propose that this represent a novel severe variant of congenital muscular dystrophy, with associated central nervous system involvement.     

Merosin-positive congenital muscular dystrophy with transient brain dysmyelination, pontocerebellar hypoplasia and mental retardation

The congenital muscular dystrophies (CMDs) are a heterogeneous group of disorders. Among these, the laminin alpha 2 chain 'merosin' deficient CMD is caused by mutations of the LAMA2 gene on chr 6q2 and Fukuyama CMD is linked to chr 9q31. We report a 7-year-old boy who was born to consanguineous healthy parents. His motor and mental development were slow. Creatine kinase (CK) was elevated (2.100 U/l), and the muscle biopsy was dystrophic. He sat unsupported at 12 months and took his first steps at 3 years of age. At 6 years of age he could walk up to 500 m. He was mentally retarded and spoke single words only. At 1 year, MR imaging of the brain showed abnormal increased periventricular T2-signal, consistent with dysmyelination as well as pontocerebellar hypoplasia and several cerebellar cysts. The pattern of gyration was normal. Follow-up at 4 years showed normalization of the previously abnormal periventricular T2-signal. Immunohistochemical analysis of the skeletal muscle showed normal expression of laminin alpha 2 for a C-terminal antibody and antibodies to the 300 and 150 kDa fragments, as well as of laminins alpha 5, beta 1, beta 2 and gamma 1. The boy has two healthy younger brothers. Linkage analysis excluded the candidate loci on chromosomes 6q2 and 9q31. As such, the patient's data are suggestive of a new form of laminin alpha 2 positive CMD characterized by transient brain dysmyelination, pontocerebellar hypoplasia and mental retardation.     

Congenital muscular dystrophy with severe retrocollis and mental retardation: a report of two siblings.

Two siblings with a congenital muscular dystrophy and severe mental retardation which was not due to dystrophin, merosin, or adhalin deficiency are described. These cases overlap with congenital muscular dystrophy of the Fukuyama-type but are less severe. Atypical features include limited facial involvement, retained ambulation, and severe retrocollis.     

A novel form of recessive limb girdle muscular dystrophy with mental retardation and abnormal expression of alpha-dystroglycan

The limb girdle muscular dystrophies are a heterogeneous group of conditions characterized by proximal muscle weakness and disease onset ranging from infancy to adulthood. We report here eight patients from seven unrelated families affected by a novel and relatively mild form of autosomal recessive limb girdle muscular dystrophy (LGMD2) with onset in the first decade of life and characterized by severe mental retardation but normal brain imaging. Immunocytochemical studies revealed a significant selective reduction of alpha-dystroglycan expression in the muscle biopsies. Linkage analysis excluded known loci for both limb girdle muscular dystrophy and congenital muscular dystrophies in the consanguineous families. We consider that this represents a novel form of muscular dystrophy with associated brain involvement. The biochemical studies suggest that it may belong to the growing number of muscular dystrophies with abnormal expression of alpha-dystroglycan.     

Facioscapulohumeral muscular dystrophy with severe mental retardation and epilepsy

We report here a case of a 20-year-old woman with facioscapulohumeral muscular dystrophy (FSHD). In this patient, the involvement of facial muscle had been present since early childhood, but obscured due to the complication of profound mental retardation. Epilepsy emerged at eight years of age. Symmetrical limb muscle weakness appeared at 15 years of age, which progressed such that she was wheelchair-bound at 18 years of age. An elevated serum creatine kinase, predominant involvement of hamstrings, scapular and abdominal muscles, as well as an impaired stapedial reflex at high tune, were compatible with the clinical features of FSHD. The diagnosis of 4q35-FSHD was confirmed by detection of a 10kb EcoRI fragment with a p13E-11 probe on a Southern blot. The intellectual disability in this patient was the most severe of all FSHD patients reported to date and has hindered a correct diagnosis. This entity should be included in the differential diagnoses for patients with muscular symptoms and accompanying mental retardation.     

Merosin-deficient congenital muscular dystrophy with mental retardation and cerebellar cysts,unlinked to the LAMA2, FCMD,MEB and CMD1B loci,in three Tunisian patients

We report three Tunisian patients affected by congenital muscular dystrophy with mental retardation and cerebellar cysts on cranial magnetic resonance imaging. The clinical features were characterized by hypotonia at birth, joint contractures associated with severe psychomotor retardation, absence of speech, inability to walk in three patients, but calf hypertrophy was noted only in two patients. Brain magnetic resonance imaging showed several cerebellar cysts and vermis hypoplasia in all of the patients. Abnormality of the white matter was present in two patients. The pattern of gyration was normal in all cases. Serum creatine kinase was elevated in all three cases and their muscle biopsy showed dystrophic changes compatible with congenital muscular dystrophy. The immunohistochemical analysis of the skeletal muscle revealed partial merosin deficiency, more pronounced for the N-terminal antibody. Linkage analysis excluded congenital muscular dystrophy loci on chromosomes 6q22, 9q31, 1p32 and 1q42. These patients constituted a particular form of congenital muscular dystrophy with a combination of severe motor delay, mental retardation, partial merosin deficiency and cerebellar cysts. Two patients showed white matter abnormalities on magnetic resonance imaging and hypertrophy of the calves. These cases, in addition to those reported previously, confirmed the large phenotypic variability in the group of secondary merosin deficiency congenital muscular dystrophy.     

Association of schizophrenia and mental retardation with facio-scapulohumeral muscular dystrophy

Three members of an Indian family with facio scapulohumeral dystrophy (FSHD linked to chromosome 4q35 with short EcoR1 segment of 23 Kb are reported where two male adults had schizophrenia. One family member developed isolated facial weakness with mild mental retardation. This genetically proven FSHD family is reported because of its uncommon associations.     

Merosin-deficient congenital muscular dystrophy with mental retardation and cerebellar cysts unlinked to the LAMA2, FCMD and MEB loci

We report a case of congenital muscular dystrophy with secondary merosin deficiency, structural involvement of the central nervous system and mental retardation in an 8-year-old girl from a consanguineous family. She had early-onset hypotonia, generalized muscle wasting, with weakness especially of the neck muscles, joint contractures, mental retardation and high creatine kinase. Muscle biopsy showed dystrophic changes with partial deficiency of the laminin ₂ chain. Cranial magnetic resonance imaging revealed multiple small cysts in the cerebellum, without cerebral cortical dysplasia or white matter changes. The laminin ₂ chain (6q2), Fukuyama type congenital muscular dystrophy (9q31–q33) and muscle–eye–brain disease (1p32–p34) loci were all excluded by linkage analysis. We suggest that this case represents a new entity in the nosology of congenital muscular dystrophy.     

Severe fascioscapulohumeral muscular dystrophy presenting with Coats' disease and mental retardation

We describe two Norwegian children with fascioscapulohumeral muscular dystrophy in whom Coats' disease, deafness, mental retardation and possible epilepsy were the presenting features. The children have a 4q35 deletion giving a small residual repeat fragment that they have inherited from their father who is a mosaic. Fundal changes consistent with bilateral Coats' disease were found in both children. The rapid development of neovascular glaucoma necessitated removal of an eye from one child that on pathological examination showed the classical features of Coats' disease. Cryotherapy was successful in maintaining sight in the other affected eyes.     

Familial lethal cardiomyopathy with mental retardation and scapuloperoneal muscular dystrophy.

A family is described with a neuromuscular disorder characterised by possible X-linked recessive inheritance, a benign, slowly progressive muscular dystrophy with predominant humeroperoneal distribution and lack of contractures or pseudohypertrophy, central nervous system involvement, myopia and lethal cardiomyopathy. The possibility of cardiac transplant as life-saving therapy is suggested.     

Multifocal glial nodules in a case of Duchenne muscular dystrophy with severe mental retardation

A case of Duchenne muscular dystrophy with multifocal hamartomatous glial nodules in the cerebral cortex is reported. The patient had suffered severe mental retardation since boyhood, dying of aspiration pneumonia at the age of 23 years. Post-mortem examination revealed an atrophic brain with normal gyri. Microscopically, multifocal small nodules composed of bizzare astrocytic cells, multinucleated cells, neuron-like cells, small astrocytes and glial fibers were found in the first, fifth and sixth layers of the prefrontal cortex. Some of the bizarre cells showed intense immunoreactivity for glial fibrillary acidic protein and moderate to very weak reactivity for ubiquitin, tau protein and αB crystallin but no immunoreactivity for neurofilament and synaptophysin, suggesting that these cells were of astrocytic origin. The nodules were considered to be due to hamartomatous changes that had occurred in the early stage of brain development, and that might have been partly responsible for the pathogenetic mechanisms of mental retardation.     

Merosin-positive congenital muscular dystrophy in two siblings with cataract and slight mental retardation.

We report on two siblings that have been followed for 14 years, with merosin-positive congenital muscular dystrophy (CMD), cataract, retinitis pigmentosa, dysversion of the optic disc, but no cerebral anomalies, except for microcephaly and slight mental retardation (MR). The younger child had three generalized seizures easily controlled by anticonvulsant therapy. Both children presented hypotonia from birth, delayed psychomotor development, generalized muscular weakness, and atrophy and joint contractures of knees and ankles. The course of the disease, apparently static during the first 10 years of life, became progressive during the second decade with loss of deambulation by the age of 13. Creatine kinase was increased in both children. Bilateral cataract was diagnosed at 6-months of age. In spite of the occurrence of microcephaly, MR was slight and the siblings acquired reading and writing skills after the aged 10. Head magnetic resonance imaging showed normal results in both siblings. The classification of these cases within the broad spectrum of CMD is difficult since most of the known muscle-eye-brain syndromes generally show severe MR and brain anomalies. We consider these cases as corresponding to the rarer syndromes of merosin-positive CMD with associated features such as cataract and MR that were particularly emphasized during the 50th ENMC International Workshop on CMD [Dubowitz V. Workshop report: 50th ENMC International workshop on congenital muscular dystrophy. Neuromusc Disord 1997;7:539-547]. Further genetic, pathological, neuroradiological, and immunocytochemical studies will be necessary for better elucidation of the classification and pathogenesis of CMD.     

Merosin-positive congenital muscular dystrophy with mental retardation, microcephaly and central nervous system abnormalities unlinked to the Fukuyama muscular dystrophy and muscular-eye-brain loci: report of three siblings

Classical merosin (2 laminin)-positive congenital muscular dystrophy is a heterogeneous subgroup of disorders; a few cases characterized by severe mental retardation, brain involvement and no ocular abnormalities were called Fukuyama-like congenital muscular dystrophy. We report a family of healthy non-consanguineous parents, with four affected siblings, of which one died at the age of 7 months due to an intercurrent illness, who presented congenital hypotonia, severe mental retardation, microcephaly, delayed psychomotor development, generalized muscular wasting and weakness with mild facial involvement, calf pseudohypertrophy, joint contractures and areflexia. Muscle biopsy disclosed severe muscular dystrophy. Immunostaining for laminin 2 80 kDa and clone Mer3/22B2 monoclonal antibodies, 1 and 1 chain was preserved. Magnetic resonance imaging findings were consistent with pontocerebellar hypoplasia, bilateral opercular abnormalities and focal cortical dysplasia as well as minute periventricular white matter changes. Clusters of small T2-weighted focal hyperintensities in both cerebellar hemispheres consistent with cysts were observed in two of the three siblings studied with magnetic resonance imaging. Ophthalmologic and cardiologic examination was normal. Haplotype analysis using microsatellite markers excluded the Fukuyama congenital muscular dystrophy, LAMA2 and muscle-eye-brain disease loci. Thus, a wider spectrum of phenotypes, gene defects and protein deficiencies might be involved in congenital muscular dystrophy with brain abnormalities.     

Mutations in ZASP define a novel form of muscular dystrophy in humans

Myofibrillar myopathy (MFM) is a morphologically distinct disorder in which disintegration of the Z-disk and then of the myofibrils is followed by abnormal accumulation of multiple proteins. Mutations in desmin, alphaB-crystallin, and myotilin, all Z-disk-related proteins, cause MFM in the minority of cases. ZASP (a Z-band alternatively spliced PDZ motif-containing protein) is another Z-disk-associated protein, and targeted deletion of ZASP in mouse causes skeletal and cardiac myopathy. We therefore searched for mutations in ZASP in 54 MFM patients and detected 3 heterozygous missense mutations in 11. Their age at onset was 44 to 73 years. Dominant inheritance was apparent in seven patients, cardiac involvement in three, and signs of peripheral neuropathy in five. Most patients had proximal and distal weakness, but in six, the weakness was greater distally than proximally. Ten carried either of two mutations in exon 6 (A147T and A165V) at or within a motif important in linking ZASP to the Z-disk; one carried a missense mutation in exon 9 (R268C). We conclude that (1) mutations in ZASP cause stereotyped MFM pathology; (2) cardiomyopathy, distal more than proximal weakness, and neuropathy are in the spectrum of zaspopathy; and (3) mutations in ZASP define a novel form of autosomal dominant muscular dystrophy in humans.     

Novel missense mutation in the L1 gene in a child with corpus callosum agenesis, retardation, adducted thumbs, spastic paraparesis, and hydrocephalus

Corpus callosum agenesis, retardation, adducted thumbs, spastic paraparesis, and hydrocephalus (CRASH syndrome) is an X-linked recessive disorder caused by mutations in the neuronal cell adhesion molecule L1 (LICAM) gene. L1 plays a key role in axon outgrowth and pathfinding during the development of the nervous system. We describe the case of a boy from the United Arab Emirates who presented with CRASH syndrome. Scanning the L1 gene of the patient resulted in the discovery of a novel missense mutation: transition of a G (guanine) to T (thymine) at position 604 (G604-->T), which results in conversion of aspartic acid to tyrosine at position 202 (D202Y) of the L1 protein. It is very likely that the cerebral dysgenesis is due to the abnormal structure and function of L1.