晚期婴儿型神经元蜡样质脂褐质沉积病

目的报道１例晚期婴儿型神经元蜡样质脂褐质沉积病（ＬＮＣＬ）的临床和病理结果。方法对１例ＬＮＣＬ病人进行临床、影像学和病理观察。结果病人２岁开始出现行走不稳和智力发育倒退,此后出现癫痫发作和视力下降,在７岁４个月死亡。头颅ＭＲＩ检查发现显著脑萎缩。病理检查显示大脑和小脑皮层的神经元严重脱失,呈海绵样改变,丘脑和纹状体的神经元也受到较严重的累及,小脑分子层出现大量的巨大轴索,残存神经元内充满黄色自发荧光的颗粒沉积物,沉积物也出现在其他躯体细胞内。电镜下沉积物主要由曲线体构成。结论此例病人的临床和病理改变符合ＬＮＣＬ的诊断,但小脑分子层出现大量的巨大轴索不同于既往报道,此例是否为一个新的ＬＮＣＬ变异型有待进一步确定     

Neuronal ceroid lipofuscinosis type-11 in an adolescent

Neuronal ceroid lipofuscinosis (NCL) is a group of progressive neurodegenerative disorders characterized by intracellular accumulation of ceroid lipopigments. Based on gene defect of NCL-associated proteins, 14 types of NCL have been described till date. NCL type 11 was first described in 2014 in two siblings as adult-onset NCL and was found to be due to a homozygous progranulin gene mutation. These siblings had progressive retinopathy, recurrent generalized seizures, moderate ataxia and subtle cognitive dysfunction. Palinopsia was present and MRI showed selective and severe cerebellar atrophy which was progressive with age. There have been no further reports of NCL 11 in literature. We here present a 14-year old girl born to second degree consanguineous couple who presented with gradually increasing frequency of seizures for the past 1?year without any signs of visual abnormalities and dementia. She had an elder sister who had progressive seizures and dementia from 8?years of age and died after few years. Her electroencephalogram showed frequent generalized epileptiform discharges and magnetic resonance imaging (MRI) showed pure cerebellar atrophy mainly affecting the vermis. MRI findings suggested a neurodegenerative disorder like NCL and prompted us to go for whole exome screen which revealed NCL type 11 due to homozygous mutation c.912G>A (p.Trp304Ter) in exon 9 of GRN gene (OMIM#614706). To the best of our knowledge this is the third case of NCL 11 and the first from Asia.     

一例晚期婴儿型神经元蜡样质脂褐素沉积病的临床、遗传和脑超微结构特点

目的 通过分析1例晚期婴儿型神经元蜡样质脂褐素沉积病(LINCL)病例.探讨LINCL的临床、遗传和病理特点. 方法 收集1例L1NCL患者的临床表现、家族史资料,并对其脑电图(EEG)、影像学和脑组织病理活检结果进行分析. 结果 EEG显示弥漫背景脑电慢化,间歇期阵发全面性棘慢波及尖慢波节律.头颅MRI检查发现患儿及其胞兄脑萎缩尤以小脑萎缩明显.脑组织活检光镜下见大脑皮层弥漫性损害,可见变性、萎缩和未成熟神经元.变性及萎缩的神经元内可见嗜银颗粒沉积,电镜下神经元胞浆中可见大量脂褐素样结构. 结论 此例患者的临床和病理改变符合LINCL的诊断,但其特殊的家族遗传史及病理特征提示其可能为新的LINCL变异型.     

Blood lymphocytes in neuronal ceroid lipofuscinosis

Ultrastructural examination of white blood cells of 8 patients with neuronal ceroid lipofuscinosis showed the characteristic cytosomes, i.e. curvilinear bodies, fingerprint profiles, osmiophilic bodies, as seen in nerve cells. The reliability of this simple technique in the diagnostic work-up of this progressive neurodegenerative disorder is emphasized.

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Sommario Vengono presentati i risultati dell'indagine ultrastrutturale dei linfociti circolanti in 8 pazienti affetti da Ceroido-Lipofuscinosi Neuronale. Nel citoplasma delle cellule ematiche sono stati osservati i medesimi citosomi (corpi curvilinei, processi ad impronte digitate, corpi osmiofili), che si riscontrano nei neuroni. Vengono sottolineati i vantaggi di questa semplice metodica nell'iter diagnostico di questa encefalopatia degenerativa a carattere progressivo.

     

Topographic heterogeneity of amyloid B-protein epitopes in brains with various forms of neuronal ceroid lipofuscinoses suggesting defective processing of amyloid precursor protein

Summary To verify our hypothesis of defective protease inhibitor domains that are encoded by abnormal processing of amyloid precursor protein (APP) in brains of patients with neuronal ceroid lipofuscinoses (NCL), immunohistochemical and cytochemical studies were performed with monoclonal antibodies (mAbs) directed against various domains of APP. For the studies, 22 autopsy brains were used: 12 with different forms of NCL, and 10 control brains. The staining procedure for the avidin-biotin complex (ABC) technique and the postembedding gold-labelled procedure for electron microscopy (EM) were employed. Of all mAbs used for the study, only mAbs generated against amyloid B-protein bound to neural tissue were affected with NCL. The strongest immunostaining of neurons and of some reactive glial cells was found in brains with the juvenile form of NCL. Only in the infantile form of the disease were some neurons overloaded with storage material weakly immunoreactive. In brains of patients with the adult form of NCL, immunoreactivity was found in affected neurons and in extracellularly deposited material of senile plaques. The results of EM study showed that the immunoreactivity was restricted to lysosomal cytosomes in neural tissue with any form of NCL selectively localized on the curvilinear and fingerprint proteinaceous component of ceroid lipofuscin. Studies performed on control aging brains and Alzheimer's disease (AD) brains confirmed previous observations of immunoreactivity being found diffusely in the protein component of some neurons containing lipopigment. The defective processing of APP in brains with NCL and AD and in ageing brains is discussed. Our present results support the notion of heterogeneity of ceroid lipofuscin storage material in various forms of NCL and underline the hypothesis that abnormalities found in the protease inhibitors or APP in the proteinaceous composition of storage lipopigment could be a key to the unknown etiology of NCL.Supported by NIH grant NS23717     

Neuronal ceroid lipofuscinoses

The neuronal ceroid lipofuscinoses (NCL) are neurodegenerative conditions that associate cognitive decline, progressive cerebellar atrophy, retinopathy, and myoclonic epilepsy. NCL result from the excessive accumulation of neuronal and extraneuronal lipopigments, despite having diverse underlying biochemical aetiologies. Here we review the clinical presentation, pathophysiology and genetics of these conditions as well as the approach to diagnosis and management.     

The adult and a new late adult forms of neuronal ceroid lipofuscinosis

Summary Three cases of the late adult form of neuronal ceroid lipofuscinosis (NCL) are reported. Two of these are siblings with a late clinical onset at ages 26 and 44 years. The third case, sporadic, has the oldest reported age for the onset of NCL, at 63 years and may be regarded as the first example of the presenile form of NCL. The clinical, morphological, histochemical, ultrastructural and genetic features of these three cases are discussed. The literature of the clinicopathological NCL cases with an onset at age of 25 and older is reviewed. The clinical and morphological differences between the late adult form and the presenile form of NCL as well as the difficulties in making the diagnosis are discussed.Supported by NIH Grant NS23717     

Perampanel attenuates myoclonus in a patient with neuronal ceroid lipofuscinoses type 2 disease

Neuronal ceroid lipofuscinoses type 2 disease (CLN2) is a very rare, autosomal recessive neurodegerative disease caused by deficient activity of the enzyme tripeptidyl peptidase 1 (TPP1). The seizures in CLN2 are polymorphic and resistant to antiepileptic drugs. In particular, myoclonus (epileptic and non-epileptic) predominant as the disease progresses. Herein, we present a child of CLN2 disease, who had near-continuous myoclonus, and was subsequently attenuated by administration of Perampanel. This girl had initially presented with language delay and generalized tonic clonic seizure at 3 years of age. The diagnosis of CLN2 was made via genetic study, which showed compound heterozygous mutation on TPP1 gene (c.622 C > T and partial gene deletion including at least exons 1–3). Currently, at the age of 8 years, there was near-continuous myoclonus (epileptic and non-epileptic), which worsen during acute illness. Eventually, she was given Perampanel with starting dose of 1 mg/day and slowly titrated upto 6 mg/day in 4 weeks. There was significant attenuation of myoclonus (>50% seizure reduction). To our knowledge, this is the first case in the literature describing the efficacy of perampanel in treating myoclonus in CLN2 disease.     

Structural basis of neuronal ceroid lipofuscinosis 1

To elucidate the basis of neuronal ceroid lipofuscinosis 1 (CLN1) from the viewpoint of enzyme structure, we constructed structural models of mutant palmitoyl protein thioesterase 1 (PPT1) proteins using molecular modeling software, jackal and TINKER. We classified the amino acid substitutions responsible for CLN1 and divided them into two groups, groups 1 and 2, based on the biochemical phenotype. Then, we examined the structural changes in the PPT1 protein for each group by calculating the solvent-accessible surface area (ASA) and the number of atoms affected. Our results revealed that the structural changes in group 1, which exhibits a complete deficiency of PPT1 activity, were generally large and located in the core region of the enzyme molecule. In group 2 exhibiting residual PPT1 activity, the structural changes in PPT1 were smaller and localized near the surface of the enzyme molecule. Coloring of affected atoms based on the distances between those in the wild type and mutants revealed the characteristic structural changes in the PPT1 protein geographically and semi-quantitatively. Structural investigation provides us with a deeper insight into the basis of CLN1.     

Correlations between genotype, ultrastructural morphology and clinical phenotype in the neuronal ceroid lipofuscinoses

The neuronal ceroid lipofuscinoses (NCLs) are a group of severe neurodegenerative diseases with onset usually in childhood and characterised by the intracellular accumulation of autofluorescent storage material. Within the last decade, mutations that cause NCL have been found in six human genes (CLN1, CLN2, CLN3, CLN5, CLN6 and CLN8). Mutations in two additional genes cause disease in animal models that share features with NCL-CTSD in sheep and mice and PPT2 in mice. Approximately 160 NCL disease-causing mutations have now been described (listed and fully cited in the NCL Mutation Database, ). Most mutations result in a classic morphology and disease phenotype, but some mutations are associated with disease that is of later onset, less severe or protracted in its course, or with atypical morphology. Seven common mutations exist, some having a worldwide distribution and others associated with families originating from specific geographical regions. This review attempts to correlate the gene, disease-causing mutation, morphology and clinical phenotype for each type of NCL.     

Neuronal ceroid lipofuscinoses: research update

This study describes the phenotype/genotype analysis of 159 probands with neuronal ceroid lipofuscinosis (37 CLN1, 72 classic CLN2, 10 variant LINCL, and 40 CLN3) collected at the New York State Institute for Basic Research in Developmental Disabilities (IBR). Phenotype/genotype comparison showed that mutations in the CLN1 gene were associated with different phenotypes: infantile, late infantile, and juvenile. Two common mutations (223A → C and 451C → T) were found in 26 of 37 CLN1 subjects (64% of alleles examined). A nonsense point mutation, 451C → T, was the most common in CLN1 subjects with infantile onset at 0–2 years, accounting for 50% of alleles studied. A missense point mutation, 223A → C, was the most common among CLN1 subjects with juvenile onset older than 4 years, accounting for 45% of alleles examined. Twenty-one other CLN1 mutations were identified in 4 of 37 subjects with infantile onset, 6 of 37 with late-infantile onset, and 6 of 37 with juvenile onset. All CLN1 probands were palmitoyl-protein thioesterase (PPT)-deficient and showed granular osmiophilic deposits (GROD) at the electron microscopic (EM) level. In the group of classic CLN2 (72 probands), two common mutations were found; an intronic 3556G → C transversion in the invariant AG of 3’ splice junction in 55% of probands, and a nonsense mutation 3670C → T in 30% of probands. Classic late-infantile onset (2–4 years) was found in 68 of 72 (95%) cases. All probands had deficiency of tripeptidyl-peptidase I (TPP1) activity and, at the EM level, curvilinear profiles. Ten probands with late-infantil onset did not show mutations in the CLN2 gene, had normal TPP1 activity, and at the EM level had mixed profiles. Further studies are in progress to identify genetic defect(s) in these subjects. The CLN3 group (40 probands) was divided into two categories: classic or typical presentation, and delayed classic or atypical presentation. All CLN3 patients had onset of symptoms after 4 years of age. In 40 probands, the 1.02-kb common deletion was found in one or two alleles of the CLN3 gene. Homozygotes for the common CLN3 deletion showed the classic phenotype. The phenotype in compound heterozygotes was either the classic or the delayed classic or atypical form. Thus, our study indicates that some mutations in the CLN1 and CLN2 genes may be associated with juvenile onset of the disease process and a more benign clinical course. Interfamilial and intrafamilial variations also were found, especially in the speed of becoming blind and neurologically disabled.     

成年型神经元蜡样质脂褐质沉积症的临床和病理特征

目的 报道2例成年型神经元蜡样质脂褐质沉积症(ANCL)临床特点和病理改变。方法 综合分析临床资料和病理结果。结果 患者临床表现为智能障碍、肌阵挛、运动障碍、行为异常及锥体外系症状。电镜下可见神经元及胶质细胞胞浆内有大量脂褐素体沉积。结论 根据起病年龄、临床表现及超微结构特征可诊断为成年型神经元蜡样质脂褐质沉积症，脑活检电镜检查是确诊本病的可靠方法。     

Infantile neuronal ceroid lipofuscinosis: the first reported case in Japan diagnosed by palmitoyl-protein thioesterase enzyme activity deficiency

We herein report on a Japanese boy with infantile neuronal ceroid lipofuscinosis (INCL). He was born of incest to a girl and her maternal uncle. His development was normal at 12 months, and began to display regression at 14 months. He lost his social smile and tracking eye movement at 16 months, and could not stand and developed severe hypotonic tetraplegia at 19 months. Myoclonic movement was observed in his trunk, eye and extremities. His height, body weight and head circumstance had been normal. Both MRI and CT scans of his head showed severe cerebral, cerebellar and brainstem atrophy. The electroretinogram showed a decrease in amplitude. Enzyme studies revealed a deficiency of palmitoyl-protein thioesterase activity in his lymphocytes at 0.98 nmol/h/mg protein (control: 90.99+/-34.23). This is the first case of INCL in Japan diagnosed by enzyme activity deficiency.     

Neuronal ceroid lipofuscinoses: detection of atypical forms

The neuronal ceroid lipofuscinoses (NCL) are progressive neurodegenerative diseases occurring in infancy and adulthood. Atypical forms of these diseases have been described and are particularly represented in the late-infantile and juvenile onset groups. Recent progress in biochemistry and molecular genetics has identified some of these variants as separate disease entities while disclosing the phenotypic variability of some classic forms. We report the result of a retrospective analysis performed on a series of 27 NCL patients, 15 of which were atypical as to clinical and/or pathological findings. Most of such patients, belonging to the late-infantile onset group and displaying homogeneous clinical-pathological features, were suggestive for CLN6. The two atypical juvenile NCL patients had features which resembled the “protracted form” of the disease. Given their relative frequency, strict clinical and pathological criteria are still the most useful tools for identifying and characterizing atypical forms and for defining phenotype-genotype correlations.     

Juvenile-onset neuronal ceroid lipofuscinosis with infantile CLN1 mutation and palmitoyl-protein thioesterase deficiency

Accurate diagnosis, especially in progressive hereditary diseases, is essential for the treatment and genetic counseling of the patient and the family. Neuronal ceroid lipofuscinoses (NCL) are amongst the most common groups of neurodegenerative diseases. Infantile, juvenile, and adult-onset types with multiple genotype–phenotype associations have been described. A fluorimetric enzyme assay for palmitoyl protein thioesterase (PPT) from leukocytes and fibroblasts has been previously developed to confirm the diagnosis of infantile NCL. We describe a patient with juvenile-onset NCL phenotype with a new CLN1 mutation and deficient PPT activity.
Over 40 different mutations have been found in patients with PPT deficiency, indicating that screening for known mutations is not an efficient way to diagnose this disorder. Therefore, PPT enzyme analysis should precede mutation analysis in suspected PPT deficiency, particularly in patients with granular osmiophilic deposits (GROD) or in patients who have negative ultrastructural data. The use of enzyme assay led to the diagnosis of this patient with juvenile-onset Finnish variant NCL with PPT deficiency, and we expect that greater awareness of the utility of the enzymatic assay may lead to identification of other similar cases awaiting a definitive diagnosis.     

Angulate lysosomes in skin biopsies of patients with degenerative neurological disorders: high frequency in neuronal ceroid lipofuscinosis

Angulate lysosomes with intralysosomal trilamellar structures were first described in patients with metabolic peroxisomal disorders. In this ultrastructural study of skin biopsies of 139 patients with degenerative neurological disorders and 45 patients with static encephalopathies, we observed angulate lysosomes with similar ultrastructure exclusively in degenerative neurological disorders. They were found in only a few cases (8%), but especially in patients with degenerative metabolic disorders (72%). Because they were never observed in patients with static encephalopathies, angulate lysosomes in the skin would seem to be a sign of progressive encephalopathy. The great majority (75%) of angulate lysosomes were associated with neuronal ceroid-lipofuscinosis (NCL). Their presence in skin biopsy could suggest the diagnosis of NCL and eliminate a peroxisomal disorder. In the latter pathology, angulate lysosomes, numerous in the liver and in the brain, were never observed in the skin. As described in pigmentary retinopathy, a conspicuous feature of NCL, we suggest that in this lysosomal storage disorder, the angulate lysosomes in skin biopsies could result from the phagocytosis of melanin. Received: 21 July 1998 / Revised: 7 October 1998, 15 December 1998 / Accepted: 17 December 1998