A novel form of familial congenital muscular dystrophy in two adolescents.

We report on two brothers (the product of first-degree consanguineous marriage; aged 15 and 12 years) who presented with severe hypotonia at birth, proximal muscle weakness associated with delayed motor milestones but normal cognitive function. Investigations (at 4 years of age) revealed mildly elevated serum creatine kinase (CK) levels (300 and 824 IU/l; N < or = 210). Muscle biopsies showed minimal change myopathy, no neurogenic atrophy but remarkable type-1 fibre predominance (up to 85.5%) without fibre-type disproportion. Clinical examination at 12 and 9 years, respectively, showed mild facial weakness and high-arched palate in both patients. The younger sibling also had ptosis but otherwise normal external ocular muscles. They showed symmetric proximal muscle weakness and wasting associated with calf-muscle hypertrophy. They could walk independently. A repeat muscle biopsy showed advanced dystrophic changes in the younger patient at the age of 10 years. Virtually all the remaining fibres were type 1. Immunohistochemistry revealed normal expression of the dystrophin-glycoprotein complex (DGC), including dystrophin, beta-dystroglycan, alpha-(adhalin), beta-, gamma-, and delta-sarcoglycan, laminin-alpha2 chain (merosin) and syntrophin. Mild dystrophic features and type-1 fibre predominance (92.5%) were seen in the biopsy of the older patient, whereas immunohistochemistry showed normal expression of the DGC. Both cases also showed clear expression of integrin alpha7 at the muscle fibre surface and in the blood vessels. Three years later, they could still walk, but with difficulty, and the older brother showed enlargement of the tongue and echocardiographic features of left ventricular dilated cardiomyopathy.

Mild congenital muscular dystrophy in two patients with an internally deleted laminin alpha2-chain.

Congenital muscular dystrophy (CMD) is a group of clinically and genetically heterogeneous disorders inherited in an autosomal recessive mode. The alpha2-chain of laminin-2 (previously called merosin) has been shown by immunohistochemical and genetic analyses to be implicated in the pathogenesis of the 'classic' form of CMD. In the 'merosin-deficient' subgroup, which represents about half of the cases, more definite evidence of the involvement of the laminin alpha2-chain has recently been reported with the identification of mutations in the gene encoding the alpha2-chain of laminin 2 (LAMA2) in CMD patients. Here we report on two siblings from a consanguineous family expressing an internally deleted laminin alpha2-chain as a result of a splice site mutation in the LAMA2 gene which causes the splicing of exon 25. The predicted protein lacks 63 amino acids in domain IVa which forms a globular structure on the short arm of the alpha2-chain. Interestingly, these patients appear mildly affected compared to others who completely lack this protein. This situation presents a striking analogy with Becker muscular dystrophy, where in-frame deletions in the dystrophin gene result in the expression of a semi-functional protein and lead to a mild phenotype.

Subacute sclerosing panencephalitis presenting as acute disseminated encephalomyelitis: a case report.

Subacute sclerosing panencephalitis is characterized by the insidious onset of diffuse cerebral dysfunction associated later with myoclonus and typical electroencephalographic changes. The disease progresses relentlessly to coma and death within 2 years. We report a case of acute onset and rapid course associated with atypical CSF, EEG and MRI features simulating acute disseminated encephalomyelitis. Brief review of relevant literature is presented.

Lethal congenital muscular dystrophy in two sibs with arthrogryposis multiplex: new entity or variant of cobblestone lissencephaly syndrome?

We report on two sisters of first degree cousin parents who were born with severe hypotonia, arthrogryposis multiplex congenita (AMC) and dysmorphic features consistent with the fetal akinesia/hypokinesia sequence. They needed assisted ventilation and each died at the age of 5 months. Both had type II lissencephaly (cobblestone lissencephaly) which was visualized by magnetic resonance imaging (MRI) in the proband. Ophthalmic evaluation revealed no ocular malformations in either of them. Brain auditory evoked potentials (BAEP) revealed bilateral severe sensorineural hearing loss in the proband, whereas an MRI-guided open muscle biopsy of the sartorius muscle (the only remaining thigh muscle) showed features of muscular dystrophy. Immunohistochemistry revealed normal dystrophin, dystrophin-associated glycoproteins (DAG) and merosin. Certain clinical and pathological features distinguish the disease seen in these sisters from reported isolated cases where lethal AMC was associated with brain dysplasia and from the main syndromes of congenital muscular dystrophy/cobblestone lissencephaly. Differences from the Walker-Warburg syndrome, which simulates it in severity, included the absence of severe hydrocephalus, normal creatine kinase (for age) and minimal (mainly periventricular) white matter abnormalities. The findings suggest either an independent entity, in the studied family, or an allelic variation of the cobblestone lissencephaly (type II lissencephaly) syndrome.

Muscular dystrophy associated with beta-Dystroglycan deficiency.

beta-Dystroglycan, a 43-kd transmembrane dystrophin-associated glycoprotein, plays an important role in linking dystrophin to the laminin-binding alpha-dystroglycan. alpha-/beta-Dystroglycan is encoded by a single gene on chromosome 3p21 and ubiquitously expressed in muscle and nonmuscle tissues. No known human diseases have been mapped to this locus. Here, we describe the selective deficiency of beta-dystroglycan in a 4-year-old Saudi boy with muscular dystrophy. The patient had a borderline elevation of serum creatine kinase level and early-onset proximal symmetrical muscle weakness and wasting without calf hypertrophy. The milder phenotype may suggest a secondary deficiency of beta-dystroglycan; however, the unique immunofluorescence labeling suggests that the patient may present a novel form of muscular dystrophy.

Clinical, biochemical and immunoelectron microscopical evidence of dual hormone production in a mammosomatotroph cell adenoma.

This paper reports the occurrence of a rare, yet distinct pituitary adenoma which was surgically removed from a 42-year-old male with both clinical and biochemical evidence of acromegaly and mild hyperprolactinaemia. The monomorphic adenoma consisted of mature cells which were ultrastructurally indistinguishable from those of a prolactinoma. Electron immunocytochemistry, including a series of double-labelling techniques using selected colloidal gold particles as markers, indicated the presence of a pituitary adenoma in which the cells were capable of simultaneously producing growth hormone and prolactin and packaging them within the same secretory granule. This is thought to represent a mammosomatotroph cell adenoma.