Japanese familial case of myoclonus–dystonia syndrome with a splicing mutation in SGCE

Myoclonus–dystonia syndrome (MDS) is a rare autosomal‐dominant movement disorder characterized by brief, frequently alcohol‐responsive myoclonic jerks that begin in childhood or early adolescence, caused by mutations in the ε‐sarcoglycan gene (SGCE). The patient was a 6‐year‐old boy. At 2 years 8 months, he had abnormal movement when he ran due to dystonia of his left leg. At 3 years 5 months, he exhibited dystonia and myoclonic movement of his arms when eating. Myoclonus was likely to develop when he felt anxiety or exhaustion. Genomic DNA showed a heterozygous mutation in SGCE (c.109 + 1 G > T). His father and uncle with the same mutation also experienced milder dystonia or myoclonic movements. SGCE mutation can cause a broad range of clinical symptoms between and within families. We should consider MDS as a differential diagnosis for patients with paroxysmal walking abnormalities and/or myoclonic movements.     

Abnormal circadian rhythm in patients with GRIN1-related developmental epileptic encephalopathy

GRIN1 encodes the obligate subunit (GluN1) of glutamate N-methyl-d-aspartate receptor (NMDAr). Pathogenic variants in GRIN1 are a well-known cause of infantile encephalopathy characterized by profound developmental delay (DD), variable epileptic phenotypes, and distinctive behavioral abnormalities. Recently, GRIN1 has also been implicated in the pathogenesis of polymicrogyria (PMG).We investigated two patients presenting with severe intellectual disability (ID), epilepsy, stereotyped movements, and abnormal ocular movements. They showed distinctive circadian rhythm alterations and sleep-wake patterns anomalies characterized by recurrent cyclic crying or laughing spells. Genetic analysis led to the identification of two distinct de novo variants in GRIN1 affecting the same amino acid residue of an important functional protein domain.Recent advances in circadian rhythm and sleep regulation suggest that abnormal GluN1 function might play a relevant pathogenetic role for the peculiar behavioral abnormalities observed in GRIN1 patients. Our cases highlight the relevance of circadian rhythm abnormalities in epileptic children as a clue toward GRIN1 encephalopathy and expand the complex phenotypic spectrum of this severe genetic disorder.     

多参数流式细胞术在儿童骨髓增生异常综合征诊断和预后评估中的应用价值

目的 评估多参数流式细胞术（MFC）及流式细胞术积分系统（FCSS）在儿童MDS诊断和预后评估中的应用价值。方法 回顾性分析42例儿童MDS初诊患者的临床资料,采用MFC分析MDS患儿骨髓各细胞群的表型及比例,并对FCSS评分与儿童MDS分型的关系、FCSS评分与国际预后积分系统（IPSS）评分的关系、FCSS评分与修订国际预后积分系统（IPSS-R）评分的关系进行相关分析。结果 异常髓系原始细胞增多者共20例（48%）,19例（45%）淋系/髓系比> 1,淋系抗原在髓系细胞异常跨系表达者14例（33%）,CD13/CD16分化抗原异常者8例（19%）,CD56异常表达者5例（12%）,3例（7%）粒系侧散射角（SSC）减弱或增强,3例（7%）有核红细胞CD36表达减弱,2例（5%）有核红细胞CD71表达减弱,髓系CD33表达缺失、粒系CD11b表达减弱或缺失、单核细胞系CD56及CD14表达缺失者各1例（2%）。FCSS评分低危组、中危组、高危组的中位总体生存时间以及无事件生存时间的差异均有统计学意义（P < 0.05）;3个组的2年总体生存率以低危组最高,中危组与高危组间的差异无统计学意义（P > 0.05）;3个组的2年无事件生存率依次95%、60%、46%,差异有统计学意义（P < 0.05）。FCSS评分与儿童MDS分型以及IPSS、IPSS-R的评分均呈正相关（P < 0.05）。结论 MFC及FCSS可以协助儿童MDS的诊断和预后评估。     

Early onset primary dystonia

Dystonia is a syndrome characterized by sustained muscle contractions, frequently causing twisting and repetitive movements or abnormal postures. It is classified by age at onset, by distribution, and by aetiology. The aetiological classification distinguishes the following categories: primary, dystonia plus, secondary, heredo-degenerative and psychogenic dystonia.Primary dystonia is defined as clinical condition characterized by dystonia as the only neurological abnormality apart from tremor. Different genetic alterations and gene loci have been mapped in familial and sporadic patients. Early onset-primary dystonia (EO-PD) is the most severe form of primary dystonia, with clinical and genetic heterogeneity. It usually starts in one body part, subsequently spreads to involve other body regions with frequent generalization. DYT1 dystonia is transmitted as an autosomal dominant trait with reduced penetrance. The unique underlying mutation is a GAG deletion in the coding region of the TOR1A gene, located at chromosome 9q34. DYT16 dystonia is a novel recessive form of EO-PD, recently described in few patients, caused by mutations in the PRKRA gene located at chromosome 2q31. At least other two loci have been mapped, but there remains a large number of patients with EO-PD in whom no genetic alteration is discovered.     

Congenital glucose–galactose malabsorption: a novel deletion within the SLC5A1 gene

Glucose–galactose malabsorption (GGM) is an autosomal recessive disease caused by mutations in the Na⁺/glucose cotransporter gene SLC5A1 (OMIM 182380, phenotype number 606824). Patients with GGM present with neonatal onset of severe life-threatening diarrhoea and dehydration. We describe a 5-day-old girl with the typical clinical course of GGM. Our clinical diagnosis was confirmed by an abnormal chromatography of the stool and normal small bowel biopsies. Mutation analysis revealed a novel, homozygous deletion within exon 10 of the SLC5A1 gene, i.e. c.1107_1109 del AGT.     

Diagnosis by whole exome sequencing of atypical infantile onset Alexander disease masquerading as a mitochondrial disorder

IntroductionThere are many similarities, both clinical and radiological, between mitochondrial leukoencephalopathies and Alexander disease, an astrogliopathy. Clinically, both can manifest with a myriad of symptoms and signs, arising from the neonatal period to adulthood. Radiologically, both can demonstrate white matter changes, signal abnormalities of basal ganglia or thalami, brainstem abnormalities and contrast enhancement of white matter structures. Magnetic resonance spectroscopy may reveal elevation of lactate in the abnormal white matter in Alexander disease making the distinction even more challenging.Patient and MethodsWe present a child who was considered to have an infantile onset mitochondrial disorder due to a combination of neurological symptoms and signs (developmental regression, failure to thrive, episodic deterioration, abnormal eye movements, pyramidal and cerebellar signs), urinary excretion of 3-methyl-glutaconic acid and imaging findings (extensive white matter changes and cerebellar atrophy) with a normal head circumference. Whole exome sequence analysis was performed.ResultsThe child was found to harbor the R416W mutation, one of the most prevalent mutations in the glial fibrillary acidic protein (GFAP) gene that causes Alexander disease.ConclusionsAlexander disease should be considered in the differential diagnosis of infantile leukoencephalopathy, even when no macrocephaly is present. Next generation sequencing is a useful aid in unraveling the molecular etiology of leukoencephalopathies.     

Early-onset or rapidly progressive scoliosis in children: Check the eyes!

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare autosomal recessive disorder characterized by the absence of conjugate horizontal eye movements, and progressive scoliosis developing in childhood and adolescence, caused by mutations in the ROBO3 gene which has an important role in axonal guidance and neuronal migration. We describe two female children aged 12 years and 18 months, with progressive scoliosis, in whom the neurological examination showed absent conjugate horizontal eye movements, but preserved vertical gaze and convergence. Cerebral Magnetic resonance imaging findings included pontine hypoplasia, absent facial colliculi, butterfly configuration of the medulla and a deep midline pontine cleft, while Diffusion tensor imaging (DTI) maps showed the absence of decussating ponto-cerebellar fibers and superior cerebellar peduncles. Somatosensory and motor evoked potential studies demonstrated ipsilateral sensory and motor responses. The diagnosis was confirmed by the identification of bi-allelic mutations in the ROBO3 gene.     

A new variable phenotype in spinocerebellar ataxia 27 (SCA 27) caused by a deletion in the FGF14 gene

We present a young boy whose mild ataxia and abnormal eye movements repeatedly deteriorated with fever, making him unable to sit or walk during fever episodes. SNP-array analysis identified a 202 kb deletion in chromosome 13q33.1 containing the fibroblast growth factor (FGF)14 gene, which is associated with spinocerebellar ataxia (SCA) 27. This 13q deletion was also present in the proband's mother and grandmother. The mother was unable to perform tandem gait walking and had abnormal eye movements but had never sought medical attention. The grandmother predominantly had a postural tremor. FGF14 regulates brain sodium channels, especially in the cerebellum. Sodium channels can be fever sensitive. This family demonstrates phenotypic variability of FGF14 deletions (SCA 27), fever sensitivity of ataxia and the added value of SNP-array analysis in making a diagnosis.     

Extraintestinal manifestations in an infant with microvillus inclusion disease: complications or features of the disease?

Microvillus inclusion disease (MVID), a rare severe congenital enteropathy characterized by intracytoplasmic microvillous inclusions and variable brush border atrophy on intestinal epithelial cells histology, is associated with defective synthesis or abnormal function of the motor protein myosin Vb encoded by the MYO5B gene. Although MYO5B gene is expressed in all epithelial tissues, it is unclear so far whether organs other than intestine are affected in MVID patients. We report a case of an infant with MVID who presented liver dysfunction, hematuria, and Pneumocystis jiroveci pneumonia during the course of the disease. It is discussed whether extraintestinal manifestations in this patient are secondary consequences of MVID or might be features of the disease associated with altered MYO5B function. Conclusions: MVID is classically included in the differential diagnosis of congenital diarrhea of secretory type. Recent advances in our knowledge regarding the role of myosin Vb in the pathophysiology of MVID is expected to clarify the clinical spectrum of the disease and the possible primary involvement of organs other than intestine.     

Hypomyelination and congenital cataract: Identification of novel mutations in two unrelated families

BackgroundHypomyelination and congenital cataract (HCC) is a rare autosomal recessive white matter disorder characterized by congenital cataract, progressive neurologic impairment, and myelin deficiency in the central and peripheral nervous system, caused by mutations in the FAM126A gene.AimsTo report three patients of two unrelated families segregating novel mutations.Methodsclinical, neurophysiological, neuroradiologic and molecular investigations were carried out.ResultsAll patients show bilateral congenital cataract and progressive neurological impairment with peripheral neuropathy. The clinical phenotype is consistent with the severe form of HCC. Brain magnetic resonance imaging show the combination of a diffuse hypomyelination with superimposed periventricular white matter signal abnormalities.Conclusionsthis study describes three additional HCC patients indicating that this recently defined leukoencephalopathy should be included in the differential diagnosis of hypomyelination in childhood. The peculiar clinical and neuroradiologic findings are useful to properly address molecular investigations and allow the differential diagnosis between HCC and other hypomyelinating forms.     

Cutis laxa,fat pads and retinopathy due to ALDH18A1 mutation and review of the literature

Autosomal recessive cutis laxa (ARCL) is a connective tissue disorder characterized by wrinkled, inelastic skin, frequently associated with a neurologic involvement and multisystem disease. Next generation sequencing was performed in genetically unsolved patients with progeroid features, neurological and eye involvement to assess the underlying etiology. We describe an 6 month old child, diagnosed with a novel, homozygous nonsense mutation c.2339T>C in exon 18 of the ALDH18A1 gene, and reviewed all reported P5CS patients.So far 10 patients were described with mutations in ALDH18A1. Features of our patient that have been described in literature included cutis laxa on hands and feet, visible veins on thorax and abdomen, joint laxity, failure to thrive, short stature, microcephaly, and severe developmental and speech delay. Furthermore, abnormal fat distribution, retinal abnormalities, undescended testis, and retinitis pigmentosa have never been described in ALDH18A1. Some features described as unique in ALDH18A1 have been observed in PYCR1 patients, thus suggesting that the phenotypic overlap is higher than previously shown.In conclusion, the clinical phenotype caused by ALDH18A1 mutations is diverse, with variable degree of progeria in children, but always in association with neurologic disease. We suggest genetic testing for possible ALDH18A1 mutations in all patients with progeroid features, like wrinkled or parchment-like skin, abnormal growth, especially with central nervous system involvement and microcephaly.     

幼年型粒单核细胞白血病的临床及实验室特征分析

目的 分析幼年型粒单核细胞白血病（JMML）的临床与实验室特征。方法 对10例初诊JMML患者的临床特征及实验室结果进行回顾性分析,并与同期确诊的28例骨髓增生异常综合征（MDS）、44例慢性粒细胞白血病（CML）患儿进行对比。结果 与CML及MDS患者相比,JMML患儿皮疹、瘀斑及淋巴结肿大的出现几率较高,而血清胆碱酯酶（ChE）最低。JMML患儿抗碱血红蛋白（HbF）最高,白细胞计数高于MDS组而低于CML组,粒红比与病态造血比例分别低于CML与MDS组;JMML组成熟单核细胞标记CD14表达较高,髓系标记CD33、CD11b、CD13及CD15的表达高于MDS组而低于CML组,差异均有统计学意义（P < 0.05）,CD7及CD2高于CML组而低于MDS组（P < 0.05）。结论 JMML患儿皮疹、瘀斑、淋巴结肿大以及ChE降低较为多见,骨髓病态造血现象较少,CD14表达明显增高。     

Leopard syndrome: a report of five cases from one family in two generations

This is the first reported family with Leopard syndrome (LS) from Bosnia and Herzegovina. We report five cases of LS from two generations of the same family. In the present series of patients from one family, all patients carry the same recurrent mutation Y279C in the PTPN11 gene, exhibiting different phenotypes and a variable expression of multiple lentigines. The diagnosis may be on clinical basis as the diagnostic clues of LS are: multiple lentigines and cafè-au-lait-spots, short stature, distinctive face, congenital heart disease, conduction abnormalities, abnormal genitalia, and sensorineural deafness. Conclusion: the clinical diagnosis of LS should be molecularly confirmed in the patient.     

Early predictors of clinical and mental outcome in tuberous sclerosis complex: A prospective study

Aim

We aimed to identify early predictors of intractable epilepsy, intellectual disability (ID) and autism spectrum disorders (ASD) in the cohort of TSC patients initially diagnosed with cardiac rhabdomyomas (CR).

Pelizaeus–Merzbacher Disease: the First Genetically Approved Case Report from Iran

Background

Classic Pelizaeus-Merzbacher disease is a rare x-linked disorder of proteolipid protein expression first described clinically in 1885. This disease is characterized by abnormal eye movements, very slow motor development and involuntary movements. The causative gene is PLP1.

Case Presentation

A 1-year-old boy was referred to our clinic due to abnormal eye movements. He had horizontal and flickering eye oscillation, psychomotor retardation, hypotonia and head nodding. We found hypomyelination in brain MRI.

Conclusion

The possibility of Pelizaeus-Merzbacher disease should be considered in boys with abnormal eye movements, psychomotor retardation and hypotonia.     

Alpha-fetoprotein,a fascinating protein and biomarker in neurology

Alpha-fetoprotein (AFP) is present in fetal serum in concentrations up to 5,000,000 μg/l. After birth, AFP gene expression is turned down with a subsequent fall of the serum concentrations of this albumin-like protein to ‘adult values’ of circa 0.5–15 μg/l from the age of 2 years onwards. Irrespective of its assumed important functions, individuals with AFP deficiency appear fully healthy. The other way around, the presence of AFP in the circulation after the first years of life doesn't seem to harm, since individuals with ‘hereditary persistence of AFP’ are also without clinical abnormalities. During pregnancy, AFP (in maternal serum) has long been recognized as a marker for congenital anomalies of the fetus. Equally well known is AFP as biomarker for hepatocellular carcinoma and some other malignancies. There are at least four neurodegenerative disorders, all inherited as autosomal recessive traits and characterized by the presence of cerebellar ataxia, abnormal ocular movements, and neuropathy, for which an elevated concentration of serum AFP is an important diagnostic biomarker. The availability of a reliable biomarker is not only important during screening or diagnostic processes, but is also relevant for objective follow-up during (future) therapeutic interventions.     

Mutation p.Leu128Pro in the 1A domain of K16 causes pachyonychia congenita with focal palmoplantar keratoderma in a Chinese family

Pachyonychia congenita (PC), a rare autosomal dominant disorder characterized by hypertrophic nail dystrophy, is classified into two main clinical subtypes: PC-1 and PC-2. PC-1 is associated with mutations in the KRT6A or KRT16 genes, whereas PC-2 is linked to KRT6B or KRT17 mutations. Blood samples were collected from three generations of a new Chinese PC-1 family, including three PC patients and five unaffected family members. A novel missense mutation p.Leu128Pro (c.383T>C) was identified in a highly conserved helix motif in domain 1A of K16. The disease haplotype carried the mutation and cosegregated with the affection status. PolyPhen2 and SIFTS analysis rated the substitution as probably damaging; Swiss-Model analysis indicated that the structure of the mutant protein contained an unnormal α-helix. Overexpression of mutant protein in cultured cells led to abnormal cell morphology. Conclusion: The wider spectrum of KRT16 mutations suggests that changes in codons 125, 127, and 132 are most commonly responsible for PC-1 and that proline substitution mutations at codons 127 or 128 may produce more severe disease. This study extends the KRT16 mutation spectrum and adds new information on the clinical and genetic diversity of PC.     

Ehlers-Danlos Syndrome Type VI in a 17-Year-Old Iranian Boy with Severe Muscular Weakness – A Diagnostic Challenge?

Background

The Ehlers-Danlos syndrome type VI (EDSVI) is an autosomal recessive connective tissue disease which is characterized by severe hypotonia at birth, progressive kyphoscoliosis, skin hyperelasticity and fragility, joint hypermobility and (sub-)luxations, microcornea, rupture of arteries and the eye globe, and osteopenia. The enzyme collagen lysyl hydroxylase (LH1) is deficient in these patients due to mutations in the PLOD1 gene.

Case Presentation

We report a 17-year-old boy, born to related parents, with severe kyphoscoliosis, scar formation, joint hypermobility and multiple dislocations, muscular weakness, rupture of an ocular globe, and a history of severe infantile hypotonia. EDS VI was suspected clinically and confirmed by an elevated ratio of urinary total lysyl pyridinoline to hydroxylysyl pyridinoline, abnormal electrophoretic mobility of the α-collagen chains, and mutation analysis.

Conclusion

Because of the high rate of consanguineous marriages in Iran and, as a consequence thereof, an increased rate of autosomal recessive disorders, we urge physicians to consider EDS VI in the differential diagnosis of severe infantile hypotonia and muscular weakness, a disorder which can easily be confirmed by the analysis of urinary pyridinolines that is highly specific, sensitive, robust, fast, non-invasive, and inexpensive.     

Relapsing encephalopathy with cerebellar ataxia are caused by variants involving p.Arg756 in ATP1A3

Mutations in ATP1A3 lead to different phenotypes having in common acute neurological decompensation episodes triggered by a specific circumstance and followed by sequelae. Alongside Alternating Hemiplegia of Childhood (AHC), Rapid-onset Dystonia Parkinsonism (RDP) and Cerebellar ataxia, Areflexia, Pes cavus, Optic atrophy, Sensorineural hearing loss syndrome (CAPOS), a new Relapsing Encephalopathy with Cerebellar Ataxia (RECA) phenotype was published in 2015. We describe herein eight new pediatric cases. Most of them had no specific history when the first neurological decompensation episode occurred, before the age of 5 years, triggered by fever with severe paralytic hypotonia followed by ataxia with or without abnormal movements. Neurological sequelae with ataxia as the predominant symptom were present after the first episode in three cases and after at least one subsequent relapse in five cases. Five of the eight cases had a familial involvement with one of the two parents affected. The phenotype–genotype correlation is unequivocal with the causal substitution always located at position 756. The pathophysiology of the dysfunctions of the mutated ATPase pump, triggered by fever is unknown. Severe recurrent neurological decompensation episodes triggered by fever, without any metabolic cause, should lead to the sequencing of ATP1A3.