title: [Muscle biopsy in children: Usefulness in 2012].
abstract: Muscle biopsy is a mainstay diagnostic tool for investigating neuromuscular disorders in children. We report the yield of pediatric muscle biopsy in a population of 415 children by a retrospective study of 419 biopsies performed between 1/01/2000 and 31/12/2009 in a neuropediatric department, including mitochondrial respiratory chain analysis for 87 children. Two hundred and fifty-five biopsies were from boys (61%) 164 from girls (39%). Their mean age at biopsy was 6.5years; 155 (37%) biopsies were obtained before the child was 5years old. Final histopathological diagnoses were: congenital myopathy (n=193, including 15 structural congenital myopathies); progressive muscular dystrophy (n=75 [18%] including 57 dystrophinopathies); congenital muscular dystrophy (n=17, including six primary merosinopathies); dermatomyositis (n=11); spinal muscular atrophy (n=9, including six atypical spinal muscular atrophies); metabolic myopathy (n=32, including 19 mitochondrial myopathies); encephalomyopathy (n=53 [13%], including 27 with a mitochondrial respiratory chain defect). Pathological diagnosis remained undetermined in 16 cases. In 184 patients (44%), the muscle biopsy revealed specific histopathological anomalies (dystrophic process; specific ultrastructural abnormalities; perifascicular atrophy; neurogenic atrophy; metabolic anomalies) enabling a precise etiological diagnosis. For 85% of progressive muscular dystrophies, the biopsy resulted in a genetic diagnosis after identification of the protein defect. In 15% of the congenital myopathies, histopathological anomalies focused attention on one or several genes. Concerning dystrophinopathies, quantification of dystrophin deficiency on the biopsy specimen contributed to the definition of the clinical phenotype: Duchenne, or Becker. In children with a myopathy, muscle biopsy is often indispensable to establish the etiological diagnosis. Based on the results from this series, muscle biopsy can provide a precise orientation in 45% of patients, leading to a genetic hypothesis.
authors.affiliation: Service de neuropédiatrie, hôpital Roger-Salengro, CHRU, rue du Professeur-Émile-Laine, 59037 Lille cedex, France; Centre de référence des maladies neuromusculaires, CHRU, 2, rue André-Verhaeghe, 59037 Lille cedex, France. Electronic address: jean-marie.cuisset@chru-lille.fr.
authors.forename: J-M
authors.initials: JM
authors.lastname: Cuisset
authors.forename: C-A
authors.initials: CA
authors.lastname: Maurage
authors.forename: A
authors.initials: A
authors.lastname: Carpentier
authors.forename: G
authors.initials: G
authors.lastname: Briand
authors.forename: A
authors.initials: A
authors.lastname: Thévenon
authors.forename: N
authors.initials: N
authors.lastname: Rouaix
authors.forename: L
authors.initials: L
authors.lastname: Vallée
mesh_terms: D000293:Adolescent; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology*; D009468:Neuromuscular Diseases / Q000145:classification / Q000151:congenital / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012189:Retrospective Studies
keywords: Biopsie musculaire; Children; Enfant; Muscle biopsy; Myopathie; Myopathy