Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Congenital fiber type disproportion (CFTD) is described clinically as muscle weakness and hypotonia with delayed motor development, usually from infancy. Muscle biopsy reveals that type 1 fibers predominate and smaller than type 2 fibers by a margin greater than 12% of the diameter of the type 2 fibers. There are no other subcellular abnormalities, and generally prognosis is good. The CFTD case is a six-month-old girl who manifested clinically as a floppy infant. A biopsied specimen from the left biceps brachii muscle revealed type 1 fiber predominance and hypoplasia with an increased number of undifferentiated type 2C fibers. Electromyogram, nerve conduction velocity and serum creatine kinase level were normal. The child learned to walk without assistance at 1 year 7 month old. Now 2-years and 10-months old, she can climb stairs without difficulty, although she cannot run fast.
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PMID:Congenital fiber type disproportion: report of one case. 228 44

Congenital Fiber Type Disproportion (CFTD) has recently been described as a consistent and stereotyped clinicopathological entity, including congenital nonprogressive hypotonia and weakness, contractures, kyphoscoliosis, high arched palate, dislocated hips, short stature, and feet deformities. Our personal experience with this condition suggests a wider disparity in the physical appearance and associated abnormalities of affected individuals than the well-defined clinical syndrome previously described. We are presenting 5 cases, including 2 siblings, whose muscle biopsies satisfy the major histological and statistical criteria for the diagnosis. Although each child clearly had hypotonia and weakness consistent with a congenital myopathy, only 3 had a sufficient number of other similarities to establish the diagnosis clinically. The clinical spectrum of the other cases ranged from one infant whose only abnormality was mild hypotonia in the legs to another whose problems included severe motor impairment, marked mental retardation, growth failure, frontal bossing, abnormal hair, and scoliosis. Even in retrospect, the diagnosis of CFTD could not have been supported on clinical grounds alone. Therefore, CFTD is a congenital myopathy whose diagnosis can be made only by muscle biopsy, rather than a distinct syndrome whose diagnosis can be assumed on the basis of clinical characteristics alone.
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PMID:Clinical variability in congenital fiber type disproportion. 738 15

Congenital fiber type disproportion is a rare type of congenital myopathy which presents as hypotonia, delayed motor milestones and dysmorphic facies. During the past 2 years we received 449 muscle biopsies, of which 4 cases were diagnosed as congenital fiber type disproportion (CFTD). In addition to CFTD, one case also had centronuclear features. Three of them were females and one was a male child. Although rare, it should be considered in the differential diagnosis of childhood muscle diseases. Histochemical staining is necessary for the diagnosis of this entity.
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PMID:Congenital fiber type disproportion: a rare type of congenital myopathy: a report of four cases. 1526 86

Congenital fiber type disproportion (CFTD) is a rare congenital myopathy characterized by hypotonia and generalized muscle weakness. Pathologic diagnosis of CFTD is based on the presence of type 1 fiber hypotrophy of at least 12% in the absence of other notable pathological findings. Mutations of the ACTA1 and SEPN1 genes have been identified in a small percentage of CFTD cases. The muscle tropomyosin 3 gene, TPM3, is mutated in rare cases of nemaline myopathy that typically exhibit type 1 fiber hypotrophy with nemaline rods, and recently mutations in the TPM3 gene were also found to cause CFTD. We screened the TPM3 gene in patients with a clinical diagnosis of CFTD, nemaline myopathy, and with undefined congenital myopathies. Mutations in TPM3 were identified in 6 out of 13 patients with CFTD, as well as in one case of nemaline myopathy. Review of muscle biopsies from patients with diagnoses of CFTD revealed that patients with a TPM3 mutation all displayed marked disproportion of fiber size, without type 1 fiber predominance. Several mutation-negative cases exhibited other abnormalities, such as central nuclei and central cores. These results support the utility of the CFTD diagnosis in directing the course of genetic testing.
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PMID:Mutations of tropomyosin 3 (TPM3) are common and associated with type 1 myofiber hypotrophy in congenital fiber type disproportion. 1995 33

Congenital myopathy with fibre type disproportion (CFTD) has been associated with mutations in ACTA1, SEPN1, RYR1 and TPM3 genes. We report the clinico-pathological and electrophysiological features of 2 unrelated cases with heterozygous TPM3 mutation. Case 1 is a 19-year-old lady who presented with motor delay in infancy, respiratory failure in early teens requiring non-invasive ventilation despite being ambulant, ptosis, axial more than proximal weakness and scoliosis. Case 2 is a 7-year-old boy with hypotonia, feeding difficulties, motor delay and scoliosis, also requiring non-invasive ventilation while ambulant. Muscle biopsies in both cases showed fibre type disproportion. Muscle MRI (Case 1) showed mild uniformly increased interstitial tissue in and around the muscles. Sequencing of TPM3 in case 1 revealed a previously described heterozygous c.503G > A(pArg168His) missense variant in exon 5 and a novel heterozygous missense mutation c.521A > C(pGlu174Ala), also in exon 5, in case 2. A mild abnormality in the single fibre EMG was documented on electrophysiology in both cases. These cases highlight the neuromuscular transmission defect in CFTD secondary to TPM3 mutations.
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PMID:Congenital fibre type disproportion associated with mutations in the tropomyosin 3 (TPM3) gene mimicking congenital myasthenia. 2095 Oct 40

Congenital fiber type disproportion (CFTD) is a form of congenital myopathy, which is defined by type 1 myofibers that are 12% smaller than type 2 myofibers, as well as a general predominance of type 1 myofibers. Conversely, myasthenia gravis (MG) is an acquired immune-mediated disease, in which the acetylcholine receptor (AChR) of the neuromuscular junction is blocked by antibodies. Thus, the anti-AChR antibody is nearly specific to MG. Herein, we report on a case of CFTD with increased anti-AChR antibody levels. A 23-month-old boy exhibited muscle hypotonia and weakness. Although he could walk by himself, he easily fell down and could not control his head for a long time. His blood test was positive for the anti-AChR antibody, while a muscle biopsy revealed characteristics of CFTD. We could not explain the relationship between MG and CFTD. However, we considered different diagnoses aside from MG, even when the patient's blood is positive for the anti-AChR antibody.
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PMID:A Case Report of Congenital Fiber Type Disproportion with an Increased Level of Anti-ACh Receptor Antibodies. 2376 16