Effectiveness of intra-thecal methotrexate in refractory Anti-N-methyl-d-aspartate receptor encephalitis.

BACKGROUND: Anti-N-methyl-d-aspartate "anti-NMDA" receptor encephalitis is one of the most common autoimmune encephalitis for which first- and second-line therapies have been recommended following international consensus. However, some refractory cases do not respond to the first- and second-line therapy and require further immune-modulatory therapies such as intra-thecal methotrexate. In this study, we reviewed six confirmed cases of refractory anti-NMDA receptor encephalitis from two tertiary centers in Saudi Arabia that required escalation of treatment and received a six-month course of intra-thecal methotrexate. The aim of this study was to evaluate the effectiveness of intra-thecal methotrexate as immunomodulatory therapy for refractory anti-NMDA receptor encephalitis. METHODS: We retrospectively evaluated six confirmed cases of refractory anti-NMDA receptor encephalitis who did not improve after first- and second-line therapy and received monthly intra-thecal methotrexate treatment course for six consecutive months. We reviewed patient demography, underlying etiologies, and compared their modified Rankin score prior to receiving intra-thecal methotrexate and six months after completing the treatment. RESULTS: Three of the six patients showed a marked response to intra-thecal methotrexate with a modified Rankin scale of 0-1 at 6-month follow-up. None of the patients experienced any side effects during or after intra-thecal methotrexate treatment, and no flareups were observed. CONCLUSION: Intra-thecal methotrexate may be a potentially effective and relatively safe escalation option for immunomodulatory therapy of refractory anti-NMDA receptor encephalitis. Future studies on intra-thecal methotrexate -specific treatment regimens may further support its utility, efficacy, and safety in treating refractory anti-NMDA receptor encephalitis.

Aromatic L-amino acid decarboxylase deficiency in countries in the Middle East: a case series and literature review.

Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare inherited neurometabolic disorder that can lead to severe physical and developmental impairment. This report includes 16 patients from the Middle East and is the largest series of patients with confirmed AADC deficiency from this region reported to date. The patients displayed a range of signs and symptoms at presentation and almost all failed to reach major motor milestones. Missed and delayed diagnoses were common leading to the late introduction of targeted treatments. Eight unique variants were identified in the DDC gene, including six missense and two intronic variants. A previously undescribed variant was identified: an intronic variant between exons 13 and 14 (c.1243-10A>G). The patients were mostly treated with currently recommended medications, including dopamine agonists, vitamin B6, and monoamine oxidase inhibitors. One patient responded well, but treatment outcomes were otherwise mostly limited to mild symptomatic improvements. Five patients had died by the time of data collection, confirming that the condition is associated with premature mortality. There is an urgent need for earlier diagnosis, particularly given the potential for gene therapy as a transformative treatment for AADC deficiency when provided at an early age.  Conclusions: Delays in the diagnosis of AADC deficiency are common. There is an urgent need for earlier diagnosis, particularly given the potential for gene therapy as a transformative treatment for AADC deficiency when provided at an early age. What is Known: • Aromatic L-amino acid decarboxylase deficiency is a rare neurometabolic disorder that can lead to severe physical and developmental impairment. • Currently recommended medications provide mostly mild symptomatic improvements. What is New: • The clinical presentation of sixteen patients with confirmed AADC deficiency varied considerably and almost all failed to reach major motor milestones. • There is an urgent need for earlier diagnosis, given the potential for gene therapy as a transformative treatment for AADC deficiency when provided at an early age.

Treatable inherited metabolic epilepsies.

Inherited metabolic diseases usually present a complex clinical picture in which seizures are one of various neurological manifestations, which include developmental delays/regression, acute encephalopathy, neuropsychiatric manifestations, and movement disorders. However, a seizure can be the prominent feature in inherited metabolic disease. The specific diagnosis of an underlying inherited metabolic disorder in epileptic patients may help design specific treatments that can improve the seizures and stop neurodegeneration. In several inherited metabolic diseases such as vitamin-responsive epilepsies and other metabolic epilepsies, seizures are refractory to antiseizure medications but respond to specific treatments based on vitamin and cofactor supplementation or diet. This review discusses our current understanding of these inherited metabolic disorders associated with epilepsy, where early diagnosis and treatment initiation will significantly improve the outcome.

A novel variant in ATM gene causes ataxia telangiectasia revealed by whole-exome sequencing.

Ataxia-Telangiectasia (A-T) is an autosomal recessive disorder caused by variants in ATM gene and characterized by progressive neurologic impairment, cerebellar ataxia, and oculo-cutaneous telangiectasia. Immunodeficiency with a recurrent sinopulmonary infections are observed in patients with A-T. Here, we report a novel stop codon variant, c.5944 C>T (p.Gln1982*), revealed by whole-exome sequencing in a 9-year old boy. He presented with recurrent upper respiratory tract infections, failure to thrive, developmental delay, ataxic gait, and bulbar telangiectasia.

Congenital disorders of glycosylation: The Saudi experience.

We retrospectively reviewed Saudi patients who had a congenital disorder of glycosylation (CDG). Twenty-seven Saudi patients (14 males, 13 females) from 13 unrelated families were identified. Based on molecular studies, the 27 CDG patients were classified into different subtypes: ALG9-CDG (8 patients, 29.5%), ALG3-CDG (7 patients, 26%), COG6-CDG (7 patients, 26%), MGAT2-CDG (3 patients, 11%), SLC35A2-CDG (1 patient), and PMM2-CDG (1 patient). All the patients had homozygous gene mutations. The combined carrier frequency of CDG for the encountered founder mutations in the Saudi population is 11.5 per 10,000, which translates to a minimum disease burden of 14 patients per 1,000,000. Our study provides comprehensive epidemiologic information and prevalence figures for each of these CDG in a large cohort of congenital disorder of glycosylation patients.

Mitochondrial iron-sulfur cluster biogenesis from molecular understanding to clinical disease.

Iron_sulfur clusters (ISCs) are known to play a major role in various protein functions. Located in the mitochondria, cytosol, endoplasmic reticulum and nucleus, they contribute to various core cellular functions. Until recently, only a few human diseases related to mitochondrial ISC biogenesis defects have been described. Such diseases include Friedreich ataxia, combined oxidative phosphorylation deficiency 19, infantile complex II/III deficiency defect, hereditary myopathy with lactic acidosis and mitochondrial muscle myopathy, lipoic acid biosynthesis defects, multiple mitochondrial dysfunctions syndromes and non ketotic hyperglycinemia due to glutaredoxin 5 gene defect. Disorders of mitochondrial import, export and translation, including sideroblastic anemia with ataxia, EVEN-PLUS syndrome and mitochondrial complex I deficiency due to nucleotide-binding protein-like protein gene defect, have also been implicated in ISC biogenesis defects. With advances in next generation sequencing technologies, more disorders related to ISC biogenesis defects are expected to be elucidated. In this article, we aim to shed the light on mitochondrial ISC biogenesis, related proteins and their function, pathophysiology, clinical phenotypes of related disorders, diagnostic approach, and future implications.

Diagnosis and management of infantile epileptic spasms syndrome (IESS) in Gulf Cooperation Council (GCC) countries: Expert consensus statement.

Despite the availability of international recommendations for the management of Infantile Epileptic Spasms Syndrome (IESS), there is a lack of recommendations adapted to the local context of clinical practice of pediatric neurology in the Gulf Cooperation Council (GCC) countries. By an initiative from the Saudi Pediatric Neurology Society (SPNS), a literature review was performed and an expert panel comprised of 13 pediatric neurologists from all GCC countries (Saudi Arabia, Kuwait, Bahrain, Oman, Qatar, and the United Arab Emirates) was subsequently convened to discuss all issues related to the management and diagnosis practices of IESS in the GCC. The overall aim of this consensus document was to develop practical recommendations to support the care of patients with IESS in the GCC and to reflect on how clinical management approaches compare with those adopted internationally.

Novel TLR7 hemizygous variant in post-COVID-19 neurological deterioration: a case report with literature review.

The neurological complications of coronavirus disease 2019 (COVID-19) can range from simple tremors and dystonia to features of encephalopathy. Toll-like receptor 7 (TLR7) belongs to a family of innate immune receptors responsible for viral RNA detection (such as SARS-CoV-2) and immune response initiation. TLR7 loss of function variants have been previously reported as genetic risk factors for severe COVID-19 infection in young patients with no comorbidities. In this case, we report a pediatric patient who developed severe long-term neurological deterioration following his COVID-19 infection. Presenting first to the clinic with episodic dystonia and finger spasticity, the patient's condition rapidly deteriorated with a significant drop in the Glasgow Coma Scale (GCS). Despite improvement following initial treatment with rituximab and intravenous immunoglobulin, the patient's symptoms relapsed, and GCS further dropped to 3/15. Serial brain magnetic resonance imaging scans revealed diffuse parenchymal atrophy, ventricular enlargement, and spinal cord thickening. Autoimmune investigations were negative but clinical whole genome sequencing prioritized four gene variants, the most significant of which was a novel frameshift null variant of the X chromosomal TLR7 gene (c.1386_1389dup, p.[His464Ilefs*7]). This case illustrates a role for TLR7 in long-term COVID-19 complications and highlights that TLR7 deficiency in the future may be addressed as a therapeutic measure.

Developmental and/or epileptic encephalopathy with spike-and-wave activation in sleep in Saudi Arabia: Electroclinical, etiologic, genetic, and outcome multicenter study.

OBJECTIVES: To investigate the clinical features of developmental and/or epileptic encephalopathy with spike-and-wave activation in sleep (D/EE-SWAS), its electrographic characteristics, and etiology and to compare the effects of different treatment strategies on the outcomes using a Saudi Arabian database. METHODS: This multicenter study included children with D/EE-SWAS who were evaluated between 2010 and 2020 at 11 tertiary centers. Data were collected on their baseline clinical features, etiologies, and treatment modalities. Seizure reduction, spike-wave index, and cognitive state were examined as potential therapeutic outcomes. RESULTS: Ninety-one children were diagnosed with D/EE-SWAS, with a median age of 7 years (IQR: 3-5) and an almost equal sex distribution. The average age at which epilepsy was diagnosed was 3 years (IQR: 5-2). A genetic/metabolic etiology was found in 35.1% of the patients, and a structural etiology was found in 27.4%. Children with underlying genetic/metabolic diseases exhibited an earlier seizure onset (P = 0.001) than children with other etiologies. Benzodiazepines (76.6%) were the most common treatment, followed by steroids (51.9%). Sodium valproate (75%) was the most frequently used antiseizure medication, followed by levetiracetam (64.9%). Children with a later seizure onset were more likely to have better clinical responses (P = 0.046), EEG responses (P = 0.012), and cognitive outcomes (P = 0.006) than children with an earlier onset. Moreover, better seizure response and electrographic response were seen in patients with bilateral interictal discharges on the EEG than otherwise. Children had a higher likelihood of both clinical and electrographic improvement with combination therapy of benzodiazepines (P = 0.001) and steroids (P = 0.001) than with other therapies. SIGNIFICANCE: This study shows a higher prevalence of genetic/metabolic causes and suggests the superior efficacy of combination therapy with steroids and benzodiazepines in D/EE-SWAS. Prospective studies that strictly assess the treatment protocols and outcomes are needed.