A 20-year Clinical and Genetic Neuromuscular Cohort Analysis in Lebanon: An International Effort.

BACKGROUND: Clinical and molecular data on the occurrence and frequency of inherited neuromuscular disorders (NMD) in the Lebanese population is scarce. OBJECTIVE: This study aims to provide a retrospective overview of hereditary NMDs based on our clinical consultations in Lebanon. METHODS: Clinical and molecular data of patients referred to a multi-disciplinary consultation for neuromuscular disorders over a 20-year period (1999-2019) was reviewed. RESULTS: A total of 506 patients were diagnosed with 62 different disorders encompassing 10 classes of NMDs. 103 variants in 49 genes were identified. In this cohort, 81.4% of patients were diagnosed with motor neuron diseases and muscular dystrophies, with almost half of these described with spinal muscular atrophy (SMA) (40.3% of patients). We estimate a high SMA incidence of 1 in 7,500 births in Lebanon. Duchenne and Becker muscular dystrophy were the second most frequently diagnosed NMDs (17% of patients). These disorders were associated with the highest number of variants (39) identified in this study. A highly heterogeneous presentation of Limb Girdle Muscular Dystrophy and Charcot-Marie-Tooth disease was notably identified. The least common disorders (5.5% of patients) involved congenital, metabolic, and mitochondrial myopathies, congenital myasthenic syndromes, and myotonic dystrophies. A review of the literature for selected NMDs in Lebanon is provided. CONCLUSIONS: Our study indicates a high prevalence and underreporting of heterogeneous forms of NMDs in Lebanon- a major challenge with many novel NMD treatments in the pipeline. This report calls for a regional NMD patient registry.

The importance of acknowledging diagnostic uncertainty in patients with new-onset paroxysmal spells.

OBJECTIVE: The aims of this study were to evaluate the frequency of paroxysmal spells of indeterminate nature (PSIN) in a large cohort of children and adults with suspected new-onset seizures, to evaluate the reasons for including patients in this category, and to calculate the rate of erroneous diagnoses if the epileptologists were compelled to label those events as epileptic seizures or nonepileptic paroxysmal spells. METHODS: Patients identified for this study participated in a prospective study evaluating patients with suspected new-onset unprovoked seizures. The workup included a detailed history and a thorough description of the spells, a 3-hour video EEG recording, and an epilepsy protocol brain MRI. Based exclusively on a detailed description of the ictal events, two epileptologists were asked to independently classify each patient into those with a definite diagnosis of unprovoked seizures or a definite diagnosis of a nonepileptic paroxysmal spells (group 1) and those with PSIN (group 2). RESULTS: A total of 1880 consecutive patients were enrolled with 255 (13.6%) included in the PSIN group. Patients with PSIN were significantly younger than those with a definite diagnosis, and PSIN were significantly more frequent in children with developmental delay. The most common reason for including patients in the PSIN group was the inability to categorically discriminate between a seizure and a nonepileptic mimicker. When the raters were compelled to classify the spells in the PSIN group, the frequencies of erroneous diagnoses ranged between 32% and 38%. The final diagnoses on those patients were made based on the results of the EEG, MRI, and follow-up visits. SIGNIFICANCE: Our data indicate that a diagnostic category of PSIN should be recognized and ought to be used in clinical practice. Acknowledging this uncertainty will result in lower frequencies of erroneous diagnoses, possible stigma, and potential exposure to unnecessary antiseizure medications.

Loss of C2orf69 defines a fatal autoinflammatory syndrome in humans and zebrafish that evokes a glycogen-storage-associated mitochondriopathy.

Human C2orf69 is an evolutionarily conserved gene whose function is unknown. Here, we report eight unrelated families from which 20 children presented with a fatal syndrome consisting of severe autoinflammation and progredient leukoencephalopathy with recurrent seizures; 12 of these subjects, whose DNA was available, segregated homozygous loss-of-function C2orf69 variants. C2ORF69 bears homology to esterase enzymes, and orthologs can be found in most eukaryotic genomes, including that of unicellular phytoplankton. We found that endogenous C2ORF69 (1) is loosely bound to mitochondria, (2) affects mitochondrial membrane potential and oxidative respiration in cultured neurons, and (3) controls the levels of the glycogen branching enzyme 1 (GBE1) consistent with a glycogen-storage-associated mitochondriopathy. We show that CRISPR-Cas9-mediated inactivation of zebrafish C2orf69 results in lethality by 8 months of age due to spontaneous epileptic seizures, which is preceded by persistent brain inflammation. Collectively, our results delineate an autoinflammatory Mendelian disorder of C2orf69 deficiency that disrupts the development/homeostasis of the immune and central nervous systems.

Salvage therapy for vagal nerve stimulator infection; Literature review and report of a delayed recurrence.

BACKGROUND: Vagal Nerve Stimulation (VNS) is one of the most common neuro-modulation based approaches for the treatment of medically intractable epilepsy. Despite advances in technology and surgical techniques, hardware infection remains a recognized and feared complication in VNS placement. Management of such infections is scarce in the literature with the majority of data available in case reports. It ranges from immediate removal of the VNS device to conservative treatment with antibiotics in an attempt to salvage the device, particularly in patients who demonstrated significant improvement in seizure frequency and quality of life. METHODS: We performed a review of the literature in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify reported cases of salvaged VNS infection. A literature search for relevant English articles was conducted using Medline. References of relevant articles were also reviewed. Articles that comprised an attempt to salvage an infected VNS were included. RESULTS: We obtained 12 articles describing an attempt to salvage an infected VNS. Out of a total of 62 reported VNS infections and 43 salvage attempts using a variety of antibiotic-based approaches, 17 cases were successfully salvaged and 26 cases failed the salvage attempt and had to be explanted eventually. Moreover, we report a case of an 18-year-old male with Lennox-Gastaut syndrome who presented21 days after VNS placement with a MRSA deep tissue infection. An attempt was made to treat the infection with long-term culture-based intravenous antibiotics, but it recurred three years later with neck wound dehiscence and positive wound culture for the same organism, and ex-plantation was thus performed. CONCLUSION: The management of VNS infections remains a dilemma for neurosurgeons. Although the idea of salvaging an infected VNS seems appealing, hardware removal seems to be inevitable despite adequate antibiotic treatment.

Dravet Syndrome in Lebanon: First Report on Cases with SCN1A Mutations.

Dravet syndrome, also known as severe myoclonic epilepsy in infancy, is a rare disease characterized by the appearance of different types of seizures in a healthy baby, triggered by various factors and stressful events. We report 8 Lebanese cases referred for molecular analysis of the SCN1A gene. Results were positive in 7 cases and revealed de novo variants at the heterozygous state in different exons of the gene for all except one, where the variant was intronic. Four variants were novel. Confirmation of Dravet syndrome is important for a better follow-up and treatment, preventing the occurrence of status epilepticus and severe neurological deterioration.

Contribution of next generation sequencing in pediatric practice in Lebanon. A Study on 213 cases.

BACKGROUND: According to the Catalogue of Transmission Genetics in Arabs, less than half of diseases reported in Lebanese patients are mapped. In the recent years, Next Generation Sequencing (NGS) techniques have significantly improved clinical diagnosis, compared to traditional sequencing methods. METHODS: A total of 213 analyses by NGS (167 by whole exome sequencing (WES) and 46 by multigene panels tests) were performed on pediatric patients across different regions of Lebanon over a period of two years (December 2015-December 2017). RESULTS: Neurological disorders were the most frequent referral demand for both WES and gene panels (122/213). Pathogenic, likely pathogenic, or variants of unknown significance were identified in 69.5% of the WES and panel patients combined. Over half of the patients with such variants had an autosomal recessive disorder. A definite molecular diagnosis (pathogenic or likely pathogenic variants) was achieved in 34.1% and 47.8% of the patients studied by WES and the multigene panels, respectively. Thirty-three novel variants were found in the cases that were molecularly solved; 26 of these being identified by WES and seven by the multigene panels. In three consanguineous families, autosomal recessive inheritance of genes previously reported as showing dominant inheritance patterns were found. Biallelism was found in six cases, digenism in four cases, and one case was trigenic. CONCLUSION: Our study thus suggests that NGS tools are valuable for an improved clinical diagnosis, and highlights that the increased adoption of such techniques will significantly further improve our understanding of the genetic basis of inherited diseases in Lebanon.

Irreversible Loss of Vision in a Child due to Occipital Infarction after Gastroenteritis.

A 2½-year-old girl developed a bilateral occipital infarct following severe gastroenteritis with bilateral vision of light perception. Evaluations for sickle cell anemia, hemolytic anemia and coagulopathies were negative. Cortical blindness is an uncommon but dramatic complication of gastroenteritis, hence the need of prompt hydration and other supportive measures to avoid irreversible visual loss or mental sequela.

Isolated digital gangrene complicating hepatitis a infection in a child.

Hepatitis A virus is rarely associated with extrahepatic complications. A child presented with a history suggesting Raynaud's phenomenon and severe digital gangrene, as a complication of hepatitis A infection. Coagulation study results (protein C, protein S, antithrombin III, and activated protein C resistance) were all normal except for anticardiolipin antibodies, which were present on initial presentation and resolved later. Antinuclear antibodies, rheumatoid factor, lupus anticoagulant, antineutrophilic cytoplasmic antibodies, and Venereal Disease Research Laboratory test were all negative. Cryoglobulins were not detected. C3 and C4 levels were normal. Blood urea nitrogen and creatinine levels were normal as well. The patient was treated with aspirin and diclofenac, and improved slowly with complete resolution of gangrene and symptoms after 3 months. She remains asymptomatic 4 years later. Transient antiphospholipid syndrome or isolated Raynaud's phenomenon may be added to the list of extrahepatic complications of hepatitis A.