脂质沉积性肌病10例临床病理分析

目的 检测抗线粒体抗体(anti-mitochondrial antibody,AMA)、BCL-2、Bax在脂质沉积性肌病(lipid storage myopathy,LSM)患者骨骼肌中的表达,探讨AMA在LSM中的诊断价值及细胞凋亡在LSM发病机制中的作用.方法 对18例患者肌肉组织活检标本进行AMA、BCL-2、Bax免疫组化染色,其中经临床、肌肉活检病理确诊的LSM患者10例,正常肌肉组织3例及非线粒体肌病组织5例作为对照组.结果 光镜下,LSM患者骨骼肌AMA免疫组化染色可见Ⅰ型肌纤维中有大量棕黄色细颗粒沉积;BCL-2在18例患者的肌纤维和小血管中有不同程度的表达,Bax在5例非线粒体肌病组织中的肌纤维和小血管中有表达.结论 LSM患者的骨骼肌纤维中存在有异常线粒体增多现象,AMA可作为诊断LSM的一个病理学指标.LSM和非线粒体肌病的发病机制中均存在凋亡因素的异常调节.     

背阔肌的组织化学特征研究

本文用酸碱预孵育肌球蛋白ATP酶法、乳酸脱氢酶法、油红O法、PAS法,研究了20只犬的背阔肌.结果表明,用肌球蛋白ATP酶法可将肌纤维分为Ⅰ型和Ⅱ型.Ⅰ型可分为3个亚型,Ⅱ型可分为ⅡA、ⅡB和ⅡC3个亚型.Ⅱ型肌纤维在背阔肌中占的比例大.Ⅱ型肌纤维含有较多糖原,Ⅰ型肌纤维含有较多脂肪颗粒.通过酶的染色观察,Ⅰ型、ⅡB和ⅡC亚型肌纤维的乳酸脱氢酶活性强弱无明显差别,ⅡA亚型肌纤维乳酸脱氢酶活性较弱.本文对背阔肌组织化学特征进行了讨论.     

9例强直性肌营养不良症组织化学和超微结构的研究

总结９例强直性肌营养不良症（ＭｙＤ）骨胳肌的病理，组织化学和超微结构的改变。光镜下观察主要改变为肌纤维退行性变，肌核内移，核链形成，肌膜下肌浆块和环行纤维形成等。肌球蛋白ＡＴＰ酶和ＮＡＤＨ－ＴＲ组织化学染色７８％显示选择性Ⅰ型纤维萎缩。电镜下观察超微结构的突出表现为肌膜出现广泛微小缺损，Ｚ带破坏，肌丝溶解，线粒体肿胀，肌质网扩张和肌纤维再生。遗传缺陷导致广泛膜功能异常，可能是引起酶代谢紊乱，线粒体     

脂质沉积性肌病八例临床病理研究

目的 观察旨质沉积性肌病的病理形态学特点,并探讨其病因及治疗效果。方法 收集经光镜和电镜检查确诊的脂质沉积性肌病８例,８例患者分别于股四头肌或者肱二头肌取活检,常规进行组织学和酶组织化学染色,光镜下观察,超薄切片,铅铀双染色,电镜下观察。并对８例患者的临床治疗用药进行分析。结果 8例患者肌催均有空泡及裂隙样改变,苏丹黑B及油红O脂肪染色示肌纤维内脂滴明显增加,电镜证实大量的脂肪滴堆积在残存的肌纤维中。病变为轻度者有3例,中度有2例,重度有3例,其中1例合并了糖原沉积病,1例合并细胞色素C氧化酶明显降低。使用肾上腺皮质激素治疗7例有效,1例无效,合并维生素B2及其他维生素等药物治疗效果好,肉毒碱治疗对系统性缺乏患者有显效。结论 脂质沉积性肌病确诊靠肌肉活检病理形态特征性改变,肾上腺皮质激素、肉毒碱、维生素、含有丰富肉毒碱食物综合治疗可获显效,由于病因多种,明确某一种病因后可针对病因特定治疗。     

脂质沉积性肌病的临床和病理分析(附8例报告)

脂质沉积性肌病 (ｌｉｐｉｄｓｔｏｒａｇｅｍｙｏｐａｔｈｙ ,ＬＳＭ )是肌肉中长链脂肪酸代谢障碍 ,致脂质沉积在肌纤维中而引起的一组肌病 ,属于常染色体隐性遗传病。其病因较多 ,但以肉毒碱缺乏所致常见。 70年代初才被认识[1] 。该病较少见 ,国内报道尚少。本文对其临床表现、肌肉病理特点及治疗进行报道与分析。临床资料一、一般资料　 8例中 ,男 4例 ,女 4例 ,年龄 12～ 36岁 ,病程 1～ 10年 ,平均 3.9年。 8例均进行肌活检组织化学病理与电镜观察而确诊。二、临床表现　起病缓慢 ,8例均明显累及四肢近端与颈项肌 ,四肢远端肌受累较…     

中央轴空病2例及文献复习

目的：探讨中央轴空病的病理特点,方法：通过HE、特殊染色及透射电镜的方法,观察2例中央轴空病患者的肌肉活检标本,并复习文献。结果：HE染色肌纤维中央有圆型深红色区,NADH－TR染色见肌纤维中央有圆型无着色的轴空区（尤其在Ⅰ型纤维）。该区PAS染色不着色,MGT染色呈紫色,电镜观察显示,轴空区肌节结构消失,肌丝排列紊乱,Z线物质呈水纹状,肌原纤维间未见线粒体,肌管,糖原和脂滴结构。结论：中央轴空病的确诊主要依靠肌活检病理诊断,组织化学,酶组织化学染色及电镜观察对该病确诊有重要意义。     

退变性颈椎失稳颈后深部肌肉的组织化学特征及其临床意义

目的：研究颈后深部肌肉的肌纤维型分布和横切面积,探讨其生理功能和在退变性颈椎失稳发病中的作用。方法：应用肌球蛋白ＡＴＰ酶染色法,观察正常人（４例）和退变性颈椎失稳患者（４例）颈后深部肌肉各型肌纤维的比例和结构特征,并测量肌纤维的横切面积。结果：正常人和退变性颈椎失稳患者颈后深部肌肉Ⅰ型和Ⅱ型纤维交织排列,横切面呈多边形或椭圆形,Ⅰ型纤维数量及横切面积均显著大于Ⅱ型纤维。退变性颈椎失稳患者肌纤维边界不清,横切面上可见小空泡,Ⅰ型纤维减少,Ⅱ型纤维增多。结论：颈后深部肌肉对维持颈段脊柱的生理姿势和运动起重要作用,肌纤维病理学改变是退变性颈椎失稳发病的重要因素之一。     

大鼠胸深肌肌纤维型的组成及分布

目的探讨SD大鼠胸深肌的肌纤维型组成和分布,借以了解该肌功能。方法采用Guth-Samaha肌球蛋白ATP酶组织化学染色法并稍做改良,对成年SD大鼠胸深肌冰冻切片进行肌纤维分型研究。结果大鼠胸深肌经肌球蛋白ATP酶组织化学染色后可明确分出2型肌纤维,即明亮色白的Ⅰ型纤维(慢缩纤维)和幽暗深褐的Ⅱ型纤维(快缩纤维),并且,两种纤维在肌内呈棋盘样均匀分布;图像分析仪下计数Ⅱ型纤维达到65%±6%,而Ⅰ纤维仅占35%±5%,前者明显高于后者(P<0.01)。结论大鼠胸深肌以Ⅱ型纤维为主,属于力量和速度型肌。     

大剂量甲状腺素对大鼠膈肌影响的实验研究

本文采用光镜SDH组织化学方法,透射电镜技术,显微图像分析技术。对给予甲状腺素后大鼠膈肌肌纤维的改变进行了定性和定量的研究。结果发现膈肌三型肌纤维出现不同程度的肌纤维萎缩,SDH活性减弱,含量减少,线粒体肿胀,空泡变性。本研究为甲亢肌病提供了形态学基础,并为甲亢肌病的发病机理提供了有益的参考。     

实验大鼠斜方肌肌纤维型组成及分布研究

目的探讨大鼠斜方肌的肌纤维型组成和分布,借以了解该肌功能。方法取成年SD大鼠斜方肌升部肌组织进行冰冻切片(8μm厚),采用Guth-Samaha肌球蛋白ATP酶组织化学染色法并稍做改良,对其进行肌纤维分型研究。结果SD大鼠斜方肌经肌球蛋白ATP酶组织化学染色后可明确分出2种肌纤维型,即白色的Ⅰ型纤维(慢缩纤维)和深褐色的Ⅱ型纤维(快缩纤维),2种肌纤维在肌内呈棋盘样均匀分布;图像分析计数其Ⅰ型纤维占(48.8±6.9)%,Ⅱ型纤维比例为(51.2±6.9)%,2者比较差异无统计学意义(P>0.05)。结论SD大鼠斜方肌2型肌纤维所占比例均等,与其维持颈背部姿势的作用一致。     

Fatal lipid storage myopathy with deficiency of cytochrome-c-oxidase and carnitine

Summary Two newborn female siblings fell ill with apathy, failure of suckling and a generalized progressive muscular hypotonia. Death occured at the age of 7 weeks, obviously caused by impairment of respiratory musculature. Biochemical studies in one child revealed carnitine deficiency especially in skeletal muscle; hepatic encephalopathy was absent. Both children had a generalized hyperaminoaciduria, an unusual finding in primary carnitine deficiency.Besides fatty metamorphosis of the liver, bilateral hydroureters and tubular calcifications of both kidneys, morphological studies showed a generalized lipid storage myopathy which predominated in Type-I-fibres and was accentuated in the muscles of the neck. Enzymehistochemical electron microscopy in longterm frozen muscle demonstrated that cytochrome-c-oxidase activity was absent not only in myopathic but also in most of the morphological unchanged muscle fibres. Only some fibres and endothelial cells displayed normal activity of mitochondria. Biochemically no cytochrome aa₃ (cytochrome-c-oxidase) could be found in skeletal muscle; cytochrome b was almost undetectable. - In newborns with fatal lipid storage myopathy and carnitine deficiency it seems necessary to look for additional defects in the respiratory chain. Enzyme histochemical electron microscopy is a sensitive method in identifying cytochrome-c-oxidase even after a 12 months period of storage.     

Inherited metabolic myopathy with storage of glycoproteins and glycosaminoglycans

Two related patients (mother and daughter, ages 28 and 5 years) showed mild to moderate weakness and atrophy of facial and shoulder muscles with congenital onset and minimal progression. Serum creatine kinase was elevated in the child. Muscle biopsy showed normal light-microscopic and histochemical findings, but scattered sarcoplasmic vacuoles with storage of granular material were evident on electron microscopy. Storage of granular material was also identified in fibroblasts which were weakly PAS-positive, stained metachromatically with toluidine blue and orthochromatically with alcian blue. Muscle glycogen values were lownormal. Repeated biochemical studies of cultured fibroblasts identified excessive storage of glycosaminoglycans and glycoproteins. The uptake of ³H-glucosamine in cultured fibroblasts was 1.7–3.4 times greater in the patients than in control individuals, while the rate of turnover of the radioisotope was normal. These findings suggest that the genetic defect in this inherited metabolic myopathy is related to excessive synthesis of glycosaminoglycans and glycoproteins.     

Diagnostische Bedeutung von Muskelbiopsien bei metabolischen Myopathien

Summary The clinical course of metabolic myopathies is dominated by progressive muscle weakness and wasting or aching contraction and recurrent rhabdomyolysis with intense exercise. Vacuolar muscle fibre degeneration is the leading pathological finding on routine histological examination. For further characterization of those histologically empty looking vacuoles, histochemistry and electron microscopy are employed. Increase of glycogen, lipid droplets or mitochondria can often be demonstrated and indicate the need for subsequent biochemical identification of the underlying metabolic defect. Some other metabolic myopathies that cause recurrent rhabdomyolysis lack myopathological abnormalities. These can only be diagnosed biochemically, but additional new histochemical screening methods might be helpful.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft und die Friedrich-Baur-Stiftung, München     

High frequency of ETFDH c.250G>A mutation in Taiwanese patients with late‐onset lipid storage myopathy

Lan M‐Y, Fu M‐H, Liu Y‐F, Huang C‐C, Chang Y‐Y, Liu J‐S, Peng C‐H, Chen S‐S. High frequency of ETFDH c.250G>A mutation in Taiwanese patients with late‐onset lipid storage myopathy. Lipid storage myopathies (LSMs) are characterized pathologically by the accumulation of lipid droplets in muscle fibers due to impaired cellular lipid metabolism. The purpose of this study was to determine etiologies and genetic mutations associated with LSMs in ethnic Han Taiwanese. The usefulness of the blood acylcarnitine (AC) profile for diagnosing LSMs in adult patients was also investigated. Nine patients were diagnosed with late‐onset LSMs following a review of muscle biopsies and medical records and were recruited retrospectively. Genetic studies were performed to detect mutations in the SLC22A5 for primary carnitine deficiency, PNPLA2 for neutral lipid storage disease with myopathy, ABHD5 for neutral lipid storage disease with ichthyosis, ETFDH for multiple acyl‐CoA dehydrogenation deficiency (MADD), and CPT2 for carnitine palmitoyltransferase II deficiency. Blood AC levels were measured by tandem mass spectrometry. The mutation c.250G>A in ETFDH was detected in seven (78%) patients, six of whom were homozygous for the variant. Patients with ETFDH mutations had elevated blood levels of ACs ranging from C8 to C16 species, a pattern consistent with MADD. ETFDH c.250G>A mutation is common in Taiwanese patients with late‐onset LSMs. The blood AC profile is a sensitive biochemical marker for diagnosing MADD arising from ETFDH mutations in adults.     

A new lipid storage myopathy observed in individuals with the Ruvalcaba-Myhre-Smith syndrome

Four patients with the Ruvalcaba-Myhre-Smith syndrome (primary macrocephaly with associated anomalies including pigmented macules on the penis in affected males, hamartomatous intestinal polyps, and lipomas) had evidence of delayed psychomotor development and/or hypotonia in childhood. Electromyography in 3 patients showed evidence of a myopathic process. Muscle biopsy in all four demonstrated a lipid storage myopathy with increased numbers of neutral lipid droplets--predominatly in type 1 fibers. The type 2 fibers were consistently smaller than expected. Electron microscopy was unremarkable except for evidence of lipid accumulation. Muscle carnitine and carnitine palmityl transferase levels were normal in one patient. This appears to be a previously unreported type of lipid storage myopathy characteristic of the Ruvalcaba-Myhre-Smith syndrome, a probable autosomal dominant trait.     

Electron microscopy in neuromuscular disorders

Electron microscopy has a strategic position in the diagnosis of neuromuscular disorders. In muscular fibers, the main abnormalities include vacuoles, inclusion bodies, and myofibrillar disorganization with or without abnormal inclusion material. Vacuolar changes include lipidic and glycogenic storage vacuoles, rimmed vacuoles, and lysosomal and autophagic vacuoles. Accumulation of abnormal inclusion material is found in nemaline myopathy, actinopathies, and hyaline body myopathy. Myofibrillar disorganization involves cores, multiminicores, and myosin chain depletion. Myofibrillar myopathies associate a pathologic pattern of myofibrillar dissolution and ectopic protein expression. They can be divided into two groups: myofibrillar myopathies with multiple expression proteins and myofibrillar myopathies with desmin and alphaB-crystallin expression only. In these two conditions, electron microscopy shows accumulation of a granulofilamentous material immunoreactive for desmin. At least three genes are implicated: desmin, alphaB-crystallin, and myotilin. Lastly, electron microscopy serves to identify changes, pathogenic or not, which are not shown up by light microscopy. Moreover, electron microscopy gives insight on pathophysiological mechanisms and can guide molecular genetics analysis.     

Cardiac ankyrin repeat protein is preferentially induced in atrophic myofibers of congenital myopathy and spinal muscular atrophy

Cardiac ankyrin repeat protein (CARP), which is structurally characterized by the presence of four ankyrin repeat motifs in its central region, is believed to be localized in the nucleus and to participate in the regulation of cardiac-specific gene expression in cardiomyocytes. However, we recently found that CARP was induced in skeletal muscle by denervation, leading us to speculate that CARP may be induced under some pathological conditions. In the present study, we immunohistochemically analyzed the expression of CARP in 11 cases of spinal muscular atrophy (SMA) and 14 cases of congenital myopathy. In SMA, CARP was expressed selectively in severely atrophic myofibers, suggesting that CARP expression may reflect the status of muscle atrophy. Furthermore, in the congenital myopathies, the expression patterns of CARP were distinct among the subtypes, which included nemaline myopathy, myotubular myopathy, central core disease, and congenital fiber type disproportion. Although CARP was preferentially expressed in severely damaged myofibers in nemaline myopathy, it was not detected in central core disease. These findings suggest that immunohistochemical evaluation of CARP may be helpful in the diagnosis of SMA and the congenital myopathies.     

线粒体肌病患者线粒体DNA的突变分析

目的分析线粒体肌病患者线粒体DNA的突变情况，为疾病诊断提供依据。方法用常规HE、酶组化染色和电镜检查等病理形态学方法对3例线粒体肌病疑似患者进行诊断，并用聚合酶链反应-单链构象多态和DNA测序等方法对患者线粒体DNA中全部22个tRNA基因进行突变筛查。结果3例患者均被确诊为线粒体肌病，其中例1tRNA—VaI基因发生A1627G纯合突变，例2tRNA—Val基因发生A1627G／A杂合突变，例3tRNA—Trp基因发生T5554C突变、tRNA—Arg基因发生A10412C／A杂合突变。结论线粒体DNA中的tRNA基因突变是线粒体肌病的重要病因之一。     

Symptomatic lipid storage in carriers for the PNPLA2 gene

Neutral lipid storage disease comprises a heterogeneous group of inherited disorders characterized by severe accumulation of cytoplasmic triglyceride droplets in several tissues and neutrophils. A novel type of autosomal recessive lipid myopathy due to PNPLA2 mutations was recently described with associated cardiac disease, myopathy and frequent infections, but without ichthyosis. Here we describe the clinical and biochemical characteristics of a long surviving patient and report on four carrier family members with diverse clinical involvement. Interestingly, heterozygous patients show neutral lipid storage in muscle and in the keratocytes of the skin, Jordans'' bodies, mild myopathy and frequent infections. Biochemical analysis of fibroblasts obtained from patients revealed increased triglyceride storage and reduced lipid droplet-associated triglyceride hydrolase activity. Together, our data implicate that the wild-type allele cannot fully compensate for the mutated dysfunctional allele of PNPLA2 leading to triglyceride accumulation in muscle and mild myopathy in PNPLA2 mutation carriers. The presence of neutral lipid droplets in the skin in PNPLA2 mutation carriers strengthens the link between NLSD and other neutral lipid storage diseases with ichthyosis.