Objective: To analyze the diagnostic value of skeletal muscle biopsy in patients with rhabdomyolysis. Methods: Clinical and pathological data of 26 patients with rhabdomyolysis from January 2002 to December 2018 undergoing muscle biopsy were collected. Results: Eighteen males and 8 females were finally recruited with median age of 6-73 (37.3±19.6) years. The average time from onset to biopsy was 44 days (median course was 30 days). All patients had acute manifestations with muscle pain and/or weakness. Serum creatine kinase was between 1 648-92 660 U/L. Muscle biopsies showed nonspecific changes in 12 cases (a few with type 2 muscle fiber atrophy, slight deposition of lipid droplets), 10 cases with necrotizing myopathy (muscle fiber necrosis and regeneration). Toxic neurogenic damages were seen in 2 cases (type 1 and type 2 angular atrophic muscle fibers with group change), lipid storage disease in 1 case (lipid droplets deposit significantly) and idiopathic inflammatory myopathy in 1 case (muscle fiber necrosis and regeneration, with lymphocyte infiltration). The etiology of non-specific pathological changes included short-term strenuous exercise in 6 patients, poisoning in two, chronic kidney disease in one, viral infection in one, hypothyroidism in one and unknown reason in one. As to patients with necrotizing myopathy, seven were poisoning or drug-related, one with hyperthyroidism, two with unknown reason. Conclusions: Among the numerous causes of rhabdomyolysis, exercise usually links nonspecific skeletal muscle changes and poisoning or drug-related disorders are commonly associated with necrotic myopathy. Rhabdomyolysis induced by primary myopathy is rare.

Objective To investigate the clinical features and laboratory results in a patient with late onset autosomal recessive spastic ataxia of Charlevoix-Saguenay ( ARSACS ) carrying novel SACS ( spastic ataxia of Charlevoix-Saguenay ) gene heterozygous mutations .Methods A 26-year-old Chinese man developed since the age of 13 a progressive weakness and stiffness of his bilateral lower limbs and gait unsteadiness.He had pyramidal tract sign in his bilateral lower limbs , cerebellar ataxia and sensory-motor polyneuropathy , with hyperelastica and swan neck-like deformities of the fingers , pes cavus and hammer toes.Funduscopy and optical coherence tomography , brain and cervical MRI , conduction velocity of peripheral nerve , motor evoked potentials , visual and brainstem auditory evoked potentials , ultrasound of peripheral nerve , hips and legs MRI , electronystagmography , and targeted capture and next generation sequencing were performed .Results Funduscopy and optical coherence tomography revealed thickening of the retinal nerve fiber layer with unclear margined optic disc .MRI revealed symmetrical linear hypointensity lesions in the pons on T 2 and T2 FLAIR weighted images , thickened bilateral cerebellar peduncles , and flattened and atrophied cervical and upper thoracic spinal cord .Nerve conduction studies showed sensory nerve action potentials were absent in four limbs , motor conduction velocity was slowed , amplitude of muscle response was significantly decreased in lower-limb nerves ( decreased by 80% -100%) but normal in upper-limb nerves.Central motor conduction time of motor evoked potential was prolonged .Targeted capture and next generation sequencing revealed novel SACS compound heterozygous mutations , c.12637 _12638delGA (p.Glu4213ArgFs*3) and c.11274_11276delAAC (p.Ile3758_Thr3759delinsMet) derived from each parent respectively , which were confirmed by Sanger sequencing analyses . Conclusions Recognizing ARSACS triad and its characteristics on fundus and brain MRI is helpful for correct diagnosis . Our findings expand the clinical and genetic spectrum of ARSACS .

Objective To summary the pathological and genetic features in nine Chinese limb girdle muscular dystrophy 2I (LGMD2I) patients.Methods Nine LGMD2I patients were recruited from Peking University First Hospital between 2011 and 2016, who came from nine unrelated and non-consanguineous families.The mean age of onset was (8.2±5.2) years (2 to 19 years), and the mean disease duration was (10.4±6.1) years (1 to 24 years).There were six males and three females, present with weakness in limb girdle muscles, four of whom accompanied with calf hypertrophy and three with scapular winging.Serum creatine kinase was 964-23 131 U/L (normal 25-190 U/L).Five of them who conducted electromyogram showed myogenic pattern.Muscle biopsy and next generation sequencing were performed in these patients, then sanger sequencing was performed to determine whether the variants co-segregated with the phenotype in these families.Results Muscle biopsy revealed myopathy features in six patients, dystrophic change in one, and only mild changes in two.Major histocompatibility complex-Ⅰ was positive in six cases, and rimmed vacuoles were found in two.There were seven mutations in fukutin-related protein (FKRP) gene.A reported mutation of c.545A>G (p.Y182C) appeared in eight cases, including three homozygotes and five compound heterozygotes.The mutation of c.1067T>C (p.Ile356Thr) was reported too.And c.1263C>A (p.Tyr421X), c.534G>T(p.Thr178Cys), c.1027G>C (p.Glu343Gln), c.1027G>T(p.Glu343X), c.1448A>G (p.Tyr483Cys) were found to be novel mutations.Conclusions LGMD2I showed large variation in myopathology.The missense mutation A545G(Y182C) is a hot spot of FKRP gene in our series.

Limb - girdle muscular dystrophy (LGMD) is a group of disorders caused by gene mutations, with proximal muscle weakness as their main manifestation. Although various subtypes of LGMD share the common feature, heterogenity exist both in clinical phenotype and genetic defects. The diagnosis should be based on the combination of the clinical symptoms, muscle imaging findings, myo-pathological changes and genetic testing. Multi - discipline management is currently for patients. There has been progress in the diagnosis and treatment of LGMD worldwide in recent years. This review will summarize the advances in the LGMD diagnosis, treatment as well as clinical features of different subtypes of LGMD in order to improve the understanding of LGMD. DOI: 10.3969/j.issn.1672-6731.2017.08.005

目的 研究线粒体病患者血液氨基酸谱和酰基肉碱谱的变化特点.方法 对50例线粒体病、20例多酰基辅酶A脱氢酶缺陷(MADD)患者和22名健康对照,使用串联质谱法检测血液中氨基酸和酰基肉碱水平.选取线粒体病组与MADD组、健康对照组分别比较差异均有统计学意义(均P＜0.05),而MADD组同健康对照组比较差异无统计学意义(P≥0.05)的氨基酸、酰基肉碱相关指标绘制ROC曲线,选取曲线下面积(AUC)最大的指标,计算其诊断线粒体病的敏感度、特异度.结果 线粒体病组谷氨酸及鸟氨酸水平分别为中位数89.80 μmol/L、27.70 μmol/L,均低于MADD组(中位数113.46 μmol/L、33.52 μmol/L,均P＜0.05)和健康对照组(中位数107.33 μmol/L、34.08 μmol/L,均P＜0.001),丙氨酸/谷氨酸比值(中位数2.72)高于MADD组(中位数1.86,P＜0.05)和健康对照组(中位数1.55,P＜0.001).线粒体病组乙酰肉碱、羟丁酰肉碱、羟异戊酰肉碱、戊二酰肉碱、羟棕榈酰肉碱水平分别为中位数27.25 μmol/L、0.28 μmol/L、0.33 μmol/L、0.10 μmol/L、0.08 μmol/L,均高于MADD组(中位数21.32μmol/L、0.17 μmol/L、0.19 μmol/L、0.09 μmol/L、0.06 μmol/L,均P＜0.05)和健康对照组(中位数21.26 μmol/L、0.18 μmol/L、0.20 μmol/L、0.07 μmol/L、0.05 μmol/L,均P＜0.01).对上述氨基酸、酰基肉碱指标绘制ROC曲线,其中丙氨酸/谷氨酸比值AUC 0.864,当丙氨酸/谷氨酸比值＞2.17时诊断线粒体病的敏感度和特异度分别为76.00％和85.71％.结论 线粒体病的血氨基酸和酰基肉碱改变具有一定规律,有可能作为该类疾病的辅助检查方法.