Genotype-phenotype correlations in ocular manifestations of Marinesco-Sjögren syndrome: Case report and literature review.

PURPOSE: This study aims to present a family with two children with MSS who presented with different ophthalmic features. We also aim to review MSS patients' ocular manifestations to provide a basis for future clinical trials and improve MSS patients' ophthalmologic care. CASE DESCRIPTION: Both patients presented with global developmental delay, microcephaly, cerebellar ataxia, and myopathy. The older sibling had developed bilateral cataracts at the age of six. Her 2 years younger sister interestingly showed bilateral hyperopic refractive error without cataracts yet. Mendeliome sequencing unraveled a novel homozygous frameshift mutation in the SIL1 gene (SIL1, NM_022464.5, c.1042dupG, p.E348Gfs*4), causing MSS. A systematic literature review revealed that cataracts appear in 96% of MSS cases with a mean onset at 3.2 years. Additional frequent ocular features were strabismus (51.6%) and nystagmus (45.2%). CONCLUSION: SIL1-related MSS is associated with marked clinical variability. Cataracts can develop later than neuromuscular features and cognitive signs. Since cataract is a relatively late finding, patients may refer to ophthalmologists for other reasons such as refractive errors, strabismus, or nystagmus. Molecular genetic testing for SIL1 is essential to facilitate early diagnosis in patients with suspected MSS.

Effect of anesthesia on electrocorticography for localization of epileptic focus: Literature review and future directions.

Intraoperative electrocorticography (ECoG) is a useful technique to guide resections in epilepsy surgery and is mostly performed under general anesthesia. In this systematic literature review, we seek to investigate the effect of anesthetic agents on the quality and reliability of ECoG for localization of the epileptic focus. We conducted a systematic search using PubMed and EMBASE until January 2019, aiming to review the effects of anesthesia on ECoG yield. Fifty-eight studies were included from 1016 reviewed. There are favorable reports for dexmedetomidine and remifentanil during ECoG recording. There is inadequate, or sometimes conflicting, evidence to support using enflurane, isoflurane, sevoflurane, and propofol. There is evidence to avoid halothane, nitrous oxide, etomidate, ketamine, thiopental, methohexital, midazolam, fentanyl, and alfentanil due to undesired effects. Depth of anesthesia, intraoperative awareness, and surgical outcomes were not consistently evaluated. Available studies provide helpful information about the effect of anesthesia on ECoG to localize the epileptic focus. The proper use of anesthetic agents and careful dose titration, and effective communication between the neurophysiologist and anesthesiologist based on ECoG activity are essential in optimizing recordings. Anesthesia is a crucial variate to consider in the design of studies investigating ECoG and related biomarkers.

Genotype-Phenotype Correlations in Charcot-Marie-Tooth Disease Due to MTMR2 Mutations and Implications in Membrane Trafficking.

Charcot-Marie-Tooth type 4 (CMT4) is an autosomal recessive severe form of neuropathy with genetic heterogeneity. CMT4B1 is caused by mutations in the myotubularin-related 2 (MTMR2) gene and as a member of the myotubularin family, the MTMR2 protein is crucial for the modulation of membrane trafficking. To enable future clinical trials, we performed a detailed review of the published cases with MTMR2 mutations and describe four novel cases identified through whole-exome sequencing (WES). The four unrelated families harbor novel homozygous mutations in MTMR2 (NM_016156, Family 1: c.1490dupC; p.Phe498IlefsTer2; Family 2: c.1479+1G>A; Family 3: c.1090C>T; p.Arg364Ter; Family 4: c.883C>T; p.Arg295Ter) and present with CMT4B1-related severe early-onset motor and sensory neuropathy, generalized muscle atrophy, facial and bulbar weakness, and pes cavus deformity. The clinical description of the new mutations reported here overlap with previously reported CMT4B1 phenotypes caused by mutations in the phosphatase domain of MTMR2, suggesting that nonsense MTMR2 mutations, which are predicted to result in loss or disruption of the phosphatase domain, are associated with a severe phenotype and loss of independent ambulation by the early twenties. Whereas the few reported missense mutations and also those truncating mutations occurring at the C-terminus after the phosphatase domain cause a rather mild phenotype and patients were still ambulatory above the age 30 years. Charcot-Marie-Tooth neuropathy and Centronuclear Myopathy causing mutations have been shown to occur in proteins involved in membrane remodeling and trafficking pathway mediated by phosphoinositides. Earlier studies have showing the rescue of MTM1 myopathy by MTMR2 overexpression, emphasize the importance of maintaining the phosphoinositides equilibrium and highlight a potential compensatory mechanism amongst members of this pathway. This proved that the regulation of expression of these proteins involved in the membrane remodeling pathway may compensate each other's loss- or gain-of-function mutations by restoring the phosphoinositides equilibrium. This provides a potential therapeutic strategy for neuromuscular diseases resulting from mutations in the membrane remodeling pathway.

Neutropenia and Increased Mean Corpuscular Volume (MCV) With Abnormal Neurologic Findings: A Case of Cobalamin D Deficiency.

BACKGROUND: Disorders of intracellular cobalamin (Cbl) metabolism are classified from A to J according to biochemical phenotype, and genetic and complementation analyses. CblD-deficient patients present with developmental, hematologic, neurologic, and metabolic findings. CLINICAL OBSERVATION: An 11-year-old boy presented with neutropenia, increased mean corpuscular volume, psychomotor retardation, and seizures. His plasma total homocysteine and urinary methylmalonic acid levels were elevated, and a homozygous nonsense mutation [p. R250X (c.748C>T] leading to premature termination of translation was identified in the MMADHC gene, which was compatible with CblD defect. CONCLUSION: In the presence of increased mean corpuscular volume and other hematologic manifestations, such as leukopenia, thrombocytopenia, and megaloblastic anemia, with severe nonspecific or mild neurologic symptoms, Cbl synthesis defects should be considered.

Brain susceptibility changes in neurologically asymptomatic pediatric patients with Wilson's disease: evaluation with quantitative susceptibility mapping.

Background Wilson's disease (WD) is a copper metabolism disorder that causes hepatolenticular degeneration. It is important to diagnose WD before central nervous system involvement. Purpose To demonstrate the early susceptibility changes associated with the copper accumulation in the brain of neurologically asymptomatic pediatric patients with WD using quantitative susceptibility mapping (QSM). Material and Methods Twelve patients with neurologically asymptomatic WD (mean age = 13.7 ± 3.3 years) and 14 age-matched controls were prospectively examined using a 1.5-T clinical scanner. Routine magnetic resonance (MR) sequences and a three-dimensional multi-echo spoiled gradient echo (GRE) sequence were used and QSM maps were reproduced. The quantitative susceptibility of corpus striatum, thalamus, substantia nigra, and pons were analyzed with the region of interest analysis on QSM maps. The susceptibility values of two groups were statistically compared using a two-sample t-test. Results Conventional MR images of the patients and control group were similar. However increased magnetic susceptibility in the thalamus, pons and left posterior putamen were observed in the patients compared to the control group ( p < 0.05). Conclusion We observed statistically increased susceptibility values in the brains of neurologically asymptomatic patients with WD although the conventional MR images were normal. This might be compatible with early brain impairment, before neurological symptoms occur.

Insights from genotype-phenotype correlations by novel SPEG mutations causing centronuclear myopathy.

Centronuclear myopathies (CNM) are a clinically and genetically heterogeneous group of congenital myopathies, defined histologically by increased number of fibres with centrally located nuclei, and type I fibre predominance in muscle biopsy. Myotubular myopathy, the X-linked form of CNM caused by mutations in the phosphoinositide phosphatase MTM1, is histologically characteristic since muscle fibres resemble myotubes. Here we present two unrelated patients with CNM and typical myotubular fibres in the muscle biopsy caused by mutations in striated muscle preferentially expressed protein kinase (SPEG). Next generation sequencing revealed novel biallelic homozygous mutations in SPEG in both cases. Patient 1 showed the c.1627_1628insA (p.Thr544Aspfs*48) mutation and patient 2 the c.9586C>T (p.Arg3196*) mutation. The clinical phenotype was distinctive in the two patients since patient 2 developed a dilated cardiomyopathy with milder myopathy features, while patient 1 showed only myopathic features without cardiac involvement. These findings expand the genotype-phenotype correlations after the initial report. Additionally, we describe whole body muscle MRI of patient 2 and we argue on the different SPEG isoforms in skeletal muscle and heart as the possible explanation leading to variable phenotypes of SPEG mutations.

Efficiency of a Combination of Pharmacological Treatment and Nondrug Interventions in Childhood Narcolepsy.

Objective Narcolepsy is a chronic sleep disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic and/or hypnopompic hallucinations, and sleep paralysis. It is one of the most important causes of excessive daytime sleepiness in the pediatric population. The aim of this study is to present the clinical and laboratory findings, and treatment results of pediatric patients with narcolepsy. Materials and Methods We studied five unrelated consecutive children with narcolepsy, focusing on clinical and laboratory features, the therapy and outcome over the 33-month follow-up period. Results The study subjects included two boys and three girls. The mean age at diagnosis was 11.8 ± 3.3 years (range: 8-16 years). Three patients had cataplexy. There were no hypnagogic hallucinations and/or sleep paralysis in any patients. All patients were educated about sleep hygiene, appropriate nutrition, and regular exercise. Three patients were treated with modafinil, while two patients received methylphenidate. Sodium oxybate was added to existing treatment in patients with cataplexy. Cataplexy attacks did not respond well to the treatment in one patient; therefore intravenous immunoglobulin therapy was given. Conclusions Early diagnosis is important to help narcoleptic patients in improving their quality of life. A combination of pharmacological treatment and nondrug interventions can greatly improve children's clinical symptoms.

Pseudotumour Cerebri Presentation in a Child Under the Gonadotropin-Releasing Hormone Agonist Treatment.

Gonadotropin-releasing hormone analogues are common treatment option in central precocious puberty in childhood as well as in endometriosis, infertility, and prostate cancer in adults. Pseudotumor cerebri is a rare side effect observed in adults. We present the case of a girl with precocious puberty treated with triptorelin acetate who developed pseudotumor cerebri after the 4th dose. She had headaches, and her blood pressure was detected to be above the 99 percentile. There were no causes underlying of hypertension such as cardiac, renal, or endocrine. Neurological examination was normal except bilateral papilledema. Cranial magnetic resonance imaging was normal. Cerebrospinal fluid (CSF) opening pressure was elevated. Triptorelin therapy was ceased and acetazolamide was applied; CSF pressure returned to normal. We observed pseudotumor cerebri after precocious puberty treatment, a finding for the first time ever seen in childhood.

A rare case of congenital fibrosis of extraocular muscle type 1A due to KIF21A mutation with Marcus Gunn jaw-winking phenomenon.

BACKGROUND: Congenital fibrosis of the extraocular muscles (CFEOM1) is classically a congenital, non-progressive, restrictive strabismus syndrome characterized by bilateral ptosis and ophthalmoplegia with an infraducted position of the globes. This autosomal dominant syndrome is caused by mutations in the KIF21A gene. METHODS AND RESULTS: In this report we describe a 5-year-old boy, and his mother, both of whom have a mutation in the KIF21A gene, who possesses typical features of CFEOM1 syndrome. Besides displaying typical features of CFEOM1, he demonstrated Marcus Gunn jaw-winking phenomenon. The patient additionally had a positive family history of such features. CONCLUSION: This is first report of the coexistence of CFEOM and Marcus Gunn jaw-winking phenomenon in a patient with a KIF21A mutation from Turkey. We explain the phenotypic findings associated with mutations in KIF21A including CFEOM1A and Marcus Gunn jaw-winking phenomenon.

Torticollis in children: an alert symptom not to be turned away.

PURPOSE: The aim of this study is to investigate the spectrum of underlying disease in children with torticollis. METHODS: We investigated the spectrum of underlying disease and to evaluate the clinical features of the children presented with torticollis in the last 2 years. RESULTS: Of the 20 children (13 girls and 7 boys with the mean age of 8 years, ranging 2 months-12 years), eight of them have craniospinal pathologies (cerebellar tumors in three, exophytic brain stem glioma, eosinophilic granuloma of C2 vertebra, neuroenteric cyst of the spinal cord, Chiari type 3 malformation, arachnoid cysts causing brainstem compression, and cerebellar empyema), followed by osseous origin in five (congenital vertebral anomalies including hemivertebrae, blocked vertebra, and segmentation anomalies), two muscular torticollis (soft tissue inflammation due to subclavian artery catheterization, myositis ossificans with sternocleidomastoid muscle atrophy), and ocular (congenital cataract and microphthalmia), Sandifer syndrome, paroxysmal torticollis, retropharyngeal abscess each in one patients were detected. Ten patients underwent surgery; two patients received medical therapy for reflux and benign paroxysmal torticollis; and one patient with torticollis due to muscle spasm and soft tissue inflammation was treated with physiotherapy. CONCLUSIONS: Various underlying disorders from relatively benign to life-threatening conditions may present with torticollis. The first step should be always a careful and complete physical examination, which must include all systems. Imaging must be performed for ruling out underlying life-threatening diseases in children with torticollis, particularly, if acquired neurological symptoms exist. Besides craniospinal tumors, ophthalmological problems and central nervous system infections should also be kept in mind. Moreover, early diagnosis of these disorders will reduce mortality and morbidity. Therefore, alertness of clinicians in pediatric and pediatric neurosurgery practice must be increased about this alert symptom.

Different etiologies of acquired torticollis in childhood.

INTRODUCTION: Torticollis can be congenital or may be acquired in childhood. Acquired torticollis occurs because of another problem and usually presents in previously normal children. The causes of acquired torticollis include ligamentous, muscular, osseous, ocular, psychiatric, and neurologic disorders. OBJECTIVE: We performed this study to evaluate the underlying causes of torticollis in childhood. MATERIAL AND METHODS: Ten children presented with complaints of torticollis between April 2007 and April 2012 were enrolled in this study. The additional findings of physical examination included neck pain, twisted neck, walking disorder, imbalance, and vomiting The identified etiologies of the enrolled children was acute disseminated encephalomyelitis in a 2.5-year-old boy, posterior fossa tumor in a 10-month-old boy, spontaneous spinal epidural hematoma in a 5-year-old hemophiliac boy, cervical osteoblastoma in a 3-year-old boy, arachnoid cyst located at posterior fossa in a 16-month-old boy, aneurysm of the anterior communicating artery in a 6-year-old girl, pontine glioma in a 10-year-old girl, and a psychogenic torticollis in a 7-year-old boy were presented. CONCLUSION: There is a wide differential diagnosis for a patient with torticollis, not just neurological in etiology which should be considered in any patient with acquired torticollis. Moreover, early diagnosis of etiological disease will reduce mortality and morbidity. Therefore, clinicians managing children with torticollis must be vigilant about underlying neurological complications.