Thursday, July 25, 2024

Ashya King update

In 2014, the parents of five-year-old brain tumour patient Ashya King removed him from NHS care and travel abroad instead.

Ashya had successfully undergone surgery to remove the tumour but the hospital planned to treat him with radiotherapy to ensure the cancer did not return.

Naghmeh and Brett King wanted their son to get proton beam therapy instead, a similar treatment to radiotherapy which is thought to have fewer side effects, but was not offered on the NHS at the time.

Ashya was taken out of Southampton General Hospital and the family travelled to France. This sparked an international manhunt which resulted in the parents being arrested in Spain.

But the High Court eventually ruled that Ashya could get proton therapy in the Czech Republic. A decade later, he is still alive and the NHS now offers some brain cancer patients proton therapy.

https://www.dailymail.co.uk/health/article-13435169/truth-foreign-cancer-clinics-terminally-ill-child-experts-alarm-unproven-treatments.html

See: https://childnervoussystem.blogspot.com/2024/07/sounding-alarm-about-unorthodox-and.html
https://childnervoussystem.blogspot.com/2020/01/ashya-kings-3-year-remission.html
https://childnervoussystem.blogspot.com/2017/07/ashya-king-and-freya-bevan-updates.html
https://childnervoussystem.blogspot.com/2015/02/ashya-king-redux_24.html

Sounding the alarm about "unorthodox" and "unproven" treatments for terminally ill children

Desperate families are raising millions of pounds every year to send their terminally-ill children abroad for 'unproven' brain cancer treatments which 'do not work', experts warn.

Overseas clinics are offering places on clinical trials for experimental drugs to young patients – but making them pay for every aspect of the care.

All have been told by NHS doctors that there is nothing more that can be done to slow the disease – so feel they have little other choice.

The medical centres – often in Mexico, Germany and the US – charge a high price, with families stumping up as much as £1 million. Most raise the cash via crowdfunding websites such as GoFundMe and JustGiving.

However, top brain tumour experts claim many of these clinics offer 'unorthodox' medicines and surgical procedures and sometimes 'take advantage' of families looking for a shred of hope.

In some cases, these treatments have a high rate of side effects, hospitalising some children, they say. And in many cases these therapies do not extend lives.

Some child brain tumour doctors told The Mail on Sunday they know of families who sought help from clinics which offered ineffective low-carbohydrate diets and cannabis oil treatments.

According to GoFundMe, around £500,000 is raised every year to fund private treatment and associated costs for children with one form of rare brain tumour alone, diffuse intrinsic pontine glioma (DIPG).

Our findings come after the Government announced last week it would spend £40 million on brain tumour research in an effort to improve the poor outcomes for the disease.

Brain Tumour Research is calling on the Government to use the money to fund more clinical trials for children with the disease, so parents are not forced to raise these large sums – or placed in extreme financial difficulty.

Childhood brain tumours are some of the trickiest diseases in the world to treat – but one type is arguably even worse than the rest.

Every year, around 30 British children are diagnosed with a diffuse midline glioma, a fast-growing and incurable brain tumour, also known as a DIPG.

While it can affect adults, the disease is most common in young children – for reasons still not understood.

The first signs are often headaches, seizures, sudden mental or behavioural changes, as well as vision or speech problems.

These tumours commonly grow around a crucial part of the brain stem known as the pons, which links the brain to the spinal cord.

Due to this sensitive position, most surgeons will not operate on DIPG patients.

The NHS typically only offers radiotherapy in such cases, which can slow the disease, but cannot cure it. Even with radiotherapy, most DIPG patients live no longer than 18 months after diagnosis.

'We know of at least five families who last year were raising money to travel overseas. The numbers taking these last-chance options shames the UK,' says Dr Karen Noble, Director of Research at Brain Tumour Research.

'Of course parents will travel the four corners of the Earth to find hope, but this hope must be based on science and clinical evidence. Our position isn't one of criticism of the families, it is one of complete understanding and outrage that this situation has been reached as the UK slides down the list of countries where clinical trials are being instigated.'

'Sadly the majority of overseas treatments do not extend the lives of children any more than standard NHS treatment,' says Dr Fernando Carceller, consultant paediatric neuro-oncologist at The Royal Marsden NHS Foundation Trust.

'And there are cases where children experience uncomfortable side effects while taking these drugs.'

Every year, around 16,000 people in the UK are diagnosed with a brain tumour. Roughly 400 of these are in children.

Fewer than a fifth of patients survive longer than five years after diagnosis.

Brain tumours are also the biggest cancer killer of children.

Clinical trials – which enable patients to access new, experimental treatments before they are approved – can offer some hope.

However there has been a 40 per cent reduction in new trials since 2017, due to a lack of funding and the impact of the Covid pandemic. News about experimental therapies often spreads through Facebook groups dedicated to brain tumour families.

Prior to the pandemic, experts say there was a surge in demand for an unproven procedure in Mexico which involved injecting chemotherapy drugs directly into the arteries that carry blood to the brain.

This was based on the theory that many cancer drugs are ineffective because they cannot pass the blood-brain barrier – a membrane filter which blocks unwanted substances from reaching the brain.

In one case, the British family of nine-year-old Lucy Moroney raised £300,000 in 2017 to send her to Mexico for the procedure.

However, less than a year after starting the treatment, Lucy died. There is still no high-quality evidence that the procedure benefited patients.

Experts say that, since then, there have been other new treatment trends that have led to parents travelling abroad.

'I've had parents asking about ketogenic [low-carbohydrate] diet and CBD [cannabis] oil clinics for their children,' says Dr Carceller.

'These trends come and go but families will cling on to anything. They don't want their children to miss out on an experimental treatment which could save them.'

He added: 'The majority of physicians at these clinics would not take on children who are too unwell to benefit. But there are doctors out there taking advantage of the desperate situation these families are in.'

Unlike when going abroad, taking part in clinical trials in the UK does not cost anything.

Eight-year-old Rudi Abbot from Edinburgh was told by the NHS in 2022 that his brain cancer could not be cured, and was sent to Seattle in the US for an experimental immune-boosting drug trial after his parents raised £110,000.

Rudi remained on the medicine for just four months before doctors concluded it had no effect. He died less than a year later.

While experts sympathise with parents doing what they can to save their children, some question whether these crowdfunding ventures are being put to good use.

'These are huge lumps of money we're talking about,' says Dr Carceller. 'In some cases, it would be enough to open a new trial in the UK in itself.

There is also a risk the patient could fall severely unwell while abroad – placing the family in even greater financial difficulty.

In 2022, George Fox, 13, from Bedfordshire travelled to Los Angeles after his parents raised £300,000 on GoFundMe to get him on an unapproved cancer therapy.

However, during the journey, his condition deteriorated and he was taken into emergency care. He never began the treatment. The family were left with a £500,000 medical bill, paid by raising another £200,000 through crowdfunding. He died months later.

'Families are away from their support network and do not have the NHS if a child deteriorates overseas,' says Prof Darren Hargrave, a paediatric neuro-oncologist at Great Ormond Street in London. 'They may find they face unexpected and massive additional costs and stress.'

However, there are some children who do benefit from travelling abroad for treatment.

In 2014, the parents of five-year-old brain tumour patient Ashya King removed him from NHS care and travel abroad instead.

Ashya had successfully undergone surgery to remove the tumour but the hospital planned to treat him with radiotherapy to ensure the cancer did not return.

Naghmeh and Brett King wanted their son to get proton beam therapy instead, a similar treatment to radiotherapy which is thought to have fewer side effects, but was not offered on the NHS at the time.

Ashya was taken out of Southampton General Hospital and the family travelled to France. This sparked an international manhunt which resulted in the parents being arrested in Spain.

But the High Court eventually ruled that Ashya could get proton therapy in the Czech Republic. A decade later, he is still alive and the NHS now offers some brain cancer patients proton therapy.

Experts say these cases are rare and that the blunt truth is that, in many cases, there is nothing that can be done for patients – particularly those with DIPG tumours.

'When I see children with these tumours, I want to make sure the child is cared for,' says Prof Hargrave. 'We want to make sure they don't suffer and that the family is supported.

'We might talk about experimental trials as an option, but we'd be honest about the chances of trial therapies working.'

Experts agree though that it is crucial the Government makes more funding available for brain cancer clinical trials in the UK.

'Trials are not a panacea but they are the best solution we have,' says Dr Carceller.

'The more patients we can get on trials in the UK, the greater chance we have at finding new cures.'

The first sign that seven-year-old Jasmine Freeman was anything but perfectly healthy was when she began to experience double vision in February 2023.

Her optician in Bracknell, Berkshire, could not find anything wrong with her eyes, so, several weeks later, Jasmine was sent to hospital for an MRI brain scan.

Her father Anthony, 37, says he got the news that night: Jasmine had a brain tumour.

The next day, a neurosurgeon further explained to Anthony and Jakki, Jasmine's mother, that she had an incurable midline glioma.

'We were told that she likely only had 12 to 18 months even if she underwent radiotherapy,' says Anthony, a former operations manager at Heathrow airport, who is separated from Jakki. 'I refused to believe that there was simply nothing that they could do.'

Anthony researched experimental overseas treatments and found a drug called Onc-201 being tested in the US and the Netherlands. The family raised £246,000 via GoFundMe for the treatment but Jasmine died in January 2024, less than a year after diagnosis. Anthony says: 'We wanted to keep her with us as long as possible.'

https://www.dailymail.co.uk/health/article-13435169/truth-foreign-cancer-clinics-terminally-ill-child-experts-alarm-unproven-treatments.html

Pelizaeus-Merzbacher siblings

My name is Robert and I live in Franklin Square, New York with my family. My wife Kristen and I have four sons; Brian (27) Trevor (25), Andrew (22), and Dylan (20). All of them are currently living at home.

We had thought our life was changing when a sonogram in 1996 revealed that Brian would be born with a bi-lateral cleft lip and palate. Our research indicated that it could be fixed soon after birth and he would be able to live a normal life. Kristen and I were prepared to face that challenge. Brian was born on May 20 of that year at 41 weeks. We were not surprised when he was brought to the neonatal ICU shortly after birth.

Shortly on, we noticed that he had nystagmus, a shaking of the eyeballs. He never reached any developmental milestones such as XYZ. We had no idea what was wrong. This was the worst part. Neither of us has a family history of neurological disorders, although I had an aunt with a cleft palate. We went to several doctors in an attempt to find a diagnosis. We were first told that it could be a birth injury due to him being born one week late and having meconium in the amniotic fluid. That could have been aided by the bi-lateral cleft palate. We also tested for a multitude of other diseases. Brian was always happy and cognizant of everything around him. He just had poor head control and couldn’t drink or eat unassisted.

Brian received physical, occupational, and speech / feeding therapy. However, none of these therapists or the physicians knew what they were treating. They just considered it to be “cerebral palsy-like.)

This continued for the next seven years. We continued with our team of doctors for Brian. We were seeing a plastic surgeon and a prosthodontist for his face, and a neurologist, orthopedist, physiatrist, ophthalmologist, gastroenterologist, nutritionist, cardiologist, as well as regular visits to his pediatrician.

Kristen gave birth on June 26, 2003 to our 4th son Dylan. Its was her fourth Cesarean section. I was excited to meet the new member of the family. I just had a feeling in my gut that something wasn’t right by just looking at him. I’m not sure if it was parental instinct or the experience at Brian’s birth which I had suppressed, but I just noticed something was wrong.

I went over to Kristen and she asked about him while she was getting her tubes tied. I told her, “I think we might have another Brian on our hands.” Her look at me said it all

Dylan went into the neonatal ICU and was discharged with us a few days later. His neurological development mirrored Brian’s, but not their personalities. Brian was a lovable child that would smile at everyone that would come up to him. Dylan knew what he wanted and made sure you knew it, and had a sarcastic smile, even at a young age.




In 2004, My son’s neurologist, Dr. Chaula Kharode, took a blood sample that was sent to Baylor University for a F.I.S.H. (fluorescence in situ hybridization) test.

We got the positive results for PMD on a Saturday. Brian and I flew to Indianapolis the following Wednesday for a meeting of the PMD Family Support group. I was surprised to see adults with the disease, and meet some of the most knowledgeable, caring, and down to earth parents I have ever met. We felt at home and relieved that it was not a death sentence.

Fast forward to the present. The six of us are living with PMD. It affects the entire family. Brian and Dylan are reliant on us for all daily life skills. They cannot sit up or eat and drink unassisted. They cannot be left home alone. Trevor works in Connecticut but lives at home to help us out. It is increasingly difficult to lift them. Durable medical equipment has been able to help especially XYZ., . Brian was also hospitalized twice in 2023 for pulmonary issues, including getting a chest tube inserted.

Brian and Dylan both attended a special needs school with Brian graduating at age 21. He now attends a day program for disabled adults. They realize they are different from the abled population but that doesn’t affect their personalities. They enjoy travelling up to their grandparent’s lake house, going to hockey games, and meeting new people.

They each have their own choices in what television shows to watch, who sits where in the van, and which setting to have the air conditioner on. They are non-verbal, but we know what they want. They definitely let us know!

We started sending them to a summer sleep-away camp for the disabled in around 2016. They love it. Dylan will let out an angry cry when we come to visit, because he thinks we are picking him up. Camping trips have to be to accessible sites, it is difficult to go to events together as a family. We are happy to send them back to camp after a three-year hiatus. The staff at Camp Loyaltown, in Hunter, New York, is wonderful. We were only worried for them the first year.

Kristen and I are realists. Any new therapeutic that comes out will probably not affect our boys, but anything to keep them comfortable and extend their lives would have to be considered. I am more concerned about future generations. PMD in the Gasperetti family will end with this generation, as we do not have the girl we always wanted.

https://www.pmdfoundation.org/blog/gasperetti-brothers

Perplexity on my part regarding XYZ.

Next-generation phenotyping for patients with ultrarare disorders

Schmidt, A., Danyel, M., Grundmann, K. et al. Next-generation phenotyping integrated in a national framework for patients with ultrarare disorders improves genetic diagnostics and yields new molecular findings. Nat Genet (2024). https://doi.org/10.1038/s41588-024-01836-1

Abstract

Individuals with ultrarare disorders pose a structural challenge for healthcare systems since expert clinical knowledge is required to establish diagnoses. In TRANSLATE NAMSE, a 3-year prospective study, we evaluated a novel diagnostic concept based on multidisciplinary expertise in Germany. Here we present the systematic investigation of the phenotypic and molecular genetic data of 1,577 patients who had undergone exome sequencing and were partially analyzed with next-generation phenotyping approaches. Molecular genetic diagnoses were established in 32% of the patients totaling 370 distinct molecular genetic causes, most with prevalence below 1:50,000. During the diagnostic process, 34 novel and 23 candidate genotype–phenotype associations were identified, mainly in individuals with neurodevelopmental disorders. Sequencing data of the subcohort that consented to computer-assisted analysis of their facial images with GestaltMatcher could be prioritized more efficiently compared with approaches based solely on clinical features and molecular scores. Our study demonstrates the synergy of using next-generation sequencing and phenotyping for diagnosing ultrarare diseases in routine healthcare and discovering novel etiologies by multidisciplinary teams.
_______________________________________________________

The majority of rare diseases have a genetic cause. The underlying genetic alteration can be found more and more easily, for example, by means of exome sequencing (ES), leading to a molecular genetic diagnosis. ES is an examination of all sections of our genetic material (DNA) that code for proteins. As part of a Germany-wide multicenter study, ES data was collected from 1,577 patients and systematically evaluated.

This made it possible to diagnose a total of 499 patients, with 34 patients showing new, previously unknown genetic diseases. The study thus makes a significant contribution to the initial description of new diseases. In addition, software based on the use of artificial intelligence (AI) was used for the first time on a broad scale to support clinical diagnosis.

The "GestaltMatcher" AI system can assist in the assessment of facial features with regard to the classification of congenital genetic syndromes. The results of the study, in which 16 university locations were involved, have been published in Nature Genetics.

Ultra-rare diseases require both multidisciplinary clinical expertise and comprehensive genetic diagnostics for optimal care. The three-year TRANSLATE NAMSE innovation fund project began at the end of 2017 with the aim of improving the care of those affected by means of modern diagnostic concepts.

Researchers from 16 university hospitals analyzed the ES data of 1,577 patients, including 1,309 children, who presented to rare disease centers as part of TRANSLATE NAMSE. The aim of the project was to find the cause of the disease in as many patients as possible using innovative examination methods.

A genetic cause of the rare disease was identified in 499 patients, 425 of whom were children. In total, the researchers found changes in 370 different genes.

"We are particularly proud of the discovery of 34 new molecular diseases, which is a great example of knowledge-generating patient care at university hospitals," says Dr. Theresa Brunet, one of the lead authors from the Institute of Human Genetics at the Klinikum rechts der Isar of the Technical University of Munich.

What happens next with the unsolved cases?

"We will examine the affected patients for whom we have not yet been able to find a diagnosis as part of the model project Genome Sequencing, or MVGenomSeq for short," says Dr. Tobias Haack, Deputy Director of the Institute of Medical Genetics and Applied Genomics at the University Hospital of Tübingen.

The MVGenomSeq builds on the success of the TRANSLATE NAMSE project and enables the analysis of clinical genomes at university hospitals throughout Germany. Unsolved cases can also be investigated in follow-up studies using new examination methods, such as long-read sequencing, which allows much longer DNA fragments to be analyzed.

"Long-read sequencing enables us to find genetic changes that are difficult to detect and we assume that we will be able to make further diagnoses using this method," says Dr. Nadja Ehmke, Head of Genome Diagnostics at Charité's Institute of Medical Genetics and Human Genetics and one of the last authors.

As part of the TRANSLATE NAMSE project, standardized procedures for extended genetic diagnostics for suspected rare diseases were also established at the participating rare disease centers, based on interdisciplinary case conferences. These were incorporated into standard care after the project was completed.

"The interdisciplinary case conferences play an important role for those affected. This enables a comprehensive clinical characterization, which is relevant for the phenotype-based evaluation of the genetic data. In addition, the detected variants can be discussed in an interdisciplinary context," says Dr. Magdalena Danyel, one of the first authors, who works as a specialist at the Institute of Medical Genetics and Human Genetics and a fellow of the Clinician Scientist Program of the Berlin Institute of Health (BIH) at Charité—Universitätsmedizin.

Rare genetic diseases can sometimes be recognized by the face

The researchers also investigated whether the supplementary use of machine learning and artificial intelligence (AI) tools improves diagnostic effectiveness and efficiency.

To this end, the "GestaltMatcher" software developed by researchers in Bonn, which uses computer-assisted facial analysis to support the person using it in the diagnosis of rare diseases, was tested on a broad scale for the first time.

The study used the sequence and image data of 224 people who had also consented to the computer-assisted analysis of their facial images, and it was shown that the AI-supported technology provides a clinical benefit.

The GestaltMatcher AI can recognize abnormalities in the face and assign them to specific diseases. An important question when assessing genetic data is: Does the phenotype match the genotype? The AI can provide support here.

"GestaltMatcher is like an expert opinion that we can provide to any medical professional in a matter of seconds. Early diagnosis is essential for those affected by rare diseases and their families. Supportive use of the software by pediatricians could already be useful in the case of abnormalities during the U7 screening at 21 to 24 months or U7a at 34 to 36 months," says corresponding author Prof. Peter Krawitz, Director of the Institute for Genomic Statistics and Bioinformatics (IGSB) at the University Hospital Bonn (UKB), where the GestaltMatcher AI is being developed.

Prof. Krawitz is also a member of the Cluster of Excellence ImmunoSensation2 and in the Transdisciplinary Research Areas (TRA) "Modeling" and "Life & Health" at the University of Bonn. The software and app can be made available to all doctors through the non-profit organization Arbeitsgemeinschaft für Gen-Diagnostik e.V. (AGD).

https://medicalxpress.com/news/2024-07-genetic-diagnostics-ultra-rare-diseases.html




Wednesday, July 24, 2024

Congenital myasthenic syndromes 2

Nathalie Smeets, Alexander Gheldof, Bart Dequeker, , Margaux Poleur , Sofia Maldonado Slootjes, Vinciane Van Parijs, Nicolas Deconinck, Pauline Dontaine,  Alicia Alonso-Jimenez, Jan De Bleecker, Willem De Ridder, Sarah Herdewyn, Stéphanie Paquay, Arnaud Vanlander, Liesbeth De Waele, Diane Beysen, Kristl G. Claeys, Nicolas Dubuisson, Isabelle Hansen, Gauthier Remiche, Sara Seneca, Véronique Bissay, Luc Régal. Congenital Myasthenic Syndromes in Belgium: Genetic and Clinical Characterization of Pediatric and Adult Patients. Pediatric Neurology, 2024-09-01, Volume 158, Pages 57-65.

Abstract

Background

Congenital myasthenic syndromes (CMS) are a group of genetic disorders characterized by impaired neuromuscular transmission. CMS typically present at a young age with fatigable muscle weakness, often with an abnormal response after repetitive nerve stimulation (RNS). Pharmacologic treatment can improve symptoms, depending on the underlying defect. Prevalence is likely underestimated. This study reports on patients with CMS followed in Belgium in 2022.

Methods

Data were gathered retrospectively from the medical charts. Only likely pathogenic and pathogenic variants were included in the analysis.

Results

We identified 37 patients, resulting in an estimated prevalence of 3.19 per 1,000,000. The patients harbored pathogenic variants in CHRNE, RAPSN, DOK7, PREPL, CHRNB1, CHRNG, COLQ , MUSK, CHRND, GFPT1, and GMPPB. CHRNE was the most commonly affected gene. Most patients showed disease onset at birth, during infancy, or during childhood. Symptom onset was at adult age in seven patients, caused by variants in CHRNE , DOK7 , MUSK , CHRND, and GMPPB . Severity and distribution of weakness varied, as did the presence of respiratory involvement, feeding problems, and extraneuromuscular manifestations. RNS was performed in 23 patients of whom 18 demonstrated a pathologic decrement. Most treatment responses were predictable based on the genotype.

Conclusions

This is the first pooled characterization of patients with CMS in Belgium. We broaden the phenotypical spectrum of pathogenic variants in CHRNE with adult-onset CMS. Systematically documenting larger cohorts of patients with CMS can aid in better clinical characterization and earlier recognition of this rare disease. We emphasize the importance of establishing a molecular genetic diagnosis to tailor treatment choices.


Daniel Natera-de Benito, Alessia Pugliese, Kiran Polavarapu, Velina Guergueltcheva, Ivailo Tournev, Albena Todorova, Joana Afonso Ribeiro, Daniel M. Fernández-Mayoralas, Carlos Ortez, Loreto Martorell, Berta Estévez-Arias, Leslie Matalonga, Steven Laurie, Cristina Jou, Jarred Lau, Rachel Thompson, Xinming Shen, Andrew G. Engel, Andres Nascimento, Hanns Lochmüller,
Duygu Selcen. Advancing the Understanding of Vesicle-Associated Membrane Protein 1-Related Congenital Myasthenic Syndrome: Phenotypic Insights, Favorable Response to 3,4-Diaminopyridine, and Clinical Characterization of Five New Cases. Pediatric Neurology, 2024-08-01, Volume 157, Pages 5-13.

Abstract

Background

Congenital myasthenic syndromes (CMS) are a group of inherited neuromuscular junction (NMJ) disorders arising from gene variants encoding diverse NMJ proteins. Recently, the VAMP1 gene, responsible for encoding the vesicle-associated membrane protein 1 (VAMP1), has been associated with CMS.

Methods

This study presents a characterization of five new individuals with VAMP1-related CMS, providing insights into the phenotype.

Results

The individuals with VAMP1-related CMS exhibited early disease onset, presenting symptoms prenatally or during the neonatal period, alongside severe respiratory involvement and feeding difficulties. Generalized weakness at birth was a common feature, and none of the individuals achieved independent walking ability. Notably, all cases exhibited scoliosis. The clinical course remained stable, without typical exacerbations seen in other CMS types. The response to anticholinesterase inhibitors and salbutamol was only partial, but the addition of 3,4-diaminopyridine (3,4-DAP) led to significant and substantial improvements, suggesting therapeutic benefits of 3,4-DAP for managing VAMP1-related CMS symptoms. Noteworthy is the identification of the VAMP1 (NM_014231.5): c.340delA; p.Ile114SerfsTer72 as a founder variant in the Iberian Peninsula and Latin America.

Conclusions

This study contributes valuable insights into VAMP1-related CMS, emphasizing their early onset, arthrogryposis, facial and generalized weakness, respiratory involvement, and feeding difficulties. Furthermore, the potential efficacy of 3,4-DAP as a useful therapeutic option warrants further exploration. The findings have implications for clinical management and genetic counseling in affected individuals. Additional research is necessary to elucidate the long-term outcomes of VAMP1-related CMS.

Thursday, July 18, 2024

Novel whole genome sequencing approaches and lessons for neuropathies

Novel Whole Genome Sequencing Approaches and Lessons for Neuropathies

June 25, 2024

Technological advancements and cost efficiencies in whole genome sequencing are driving the discovery of repeat expansions associated with inherited neuropathies. Dr. Stephan Zuchner, Professor of Human Genetics and Neurology at the University of Miami Miller School of Medicine, highlighted the importance of long-range human genome sequencing at the 2024 Peripheral Nerve System (PNS) Annual Meeting in Montreal, Canada, noting that approaches like PacBio, Oxford Nanopore, and Optical Genome Mapping are crucial for evaluating neuropathy-associated structural variations. He pointed out the challenges of next-generation sequencing (NGS) technologies: a significant portion of variations fall outside the coding region, and half of our genome is comprised of repeat elements.

"By far, the largest group of variants are rare variants. So rare variants are actually the most common type of variant." Dr. Zuchner discussed significant advancements in genomic analysis for neurological disorders, emphasizing the potential of NGS technologies in identifying causative genes of peripheral neuropathies. He stressed the importance of understanding the genetic basis of neuropathies and the potential for clinical trials, noting that "what we see in inherited neuropathies might be quite meaningful for other types of peripheral neuropathies."

Dr. Zuchner also discussed the discovery of three causative genes of neuropathy where structural changes were identified through short-read sequencing. However, he explained, "If we had long-read sequencing, we would have discovered them much faster." These three genes were RFC1, SORD, and FGF14. RFC1 and FGF14 are linked to late-onset cerebellar ataxia, and SORD is involved in Charcot-Marie-Tooth disease and diabetic neuropathy. Further elaborating on genomic instability and its implications for therapy, Dr. Zuchner explained that the FGF14 GAA repeat expansion locus exhibits germline meiotic instability, with inheritance from parents leading to size changes. He discussed how a protective sequence in FGF14 prevents repeat instability. "We have discovered a 70-base pair sequence just in front of the FGF14 repeat that is completely protective of such dynamic expansion. We looked at thousands of long-range sequences, and we can see the complete discrimination between people who have this 70-base pair protective physical variant versus those who don't. It really determines if you will expect or you will not expect ataxia."

Dr. Zuchner noted the potential of using the latest advancements in artificial intelligence and machine learning to predict classified genome variants into binary pathogenic categories by treating DNA and resulting protein sequences like a language. Large language models can yield accurate classifications of protein variants and determine their pathogenicity by comparing sequence variations across different species.

This Omics session shed light on the critical role of long-range whole genome sequencing and artificial intelligence in evaluating structural variations and understanding the complexities of rare variants in neuropathies. It also highlighted the potential for developing targeted therapies based on genomic insights.

https://focusonneurology.com/pns2024/novel-whole-genome-sequencing-approaches-and-lessons-for-neuropathies




Congenital myasthenic syndromes

Kediha MI, Tazir M, Sternberg D, Eymard B, Ali Pacha L. Innovative Therapeutic Approaches in Congenital Myasthenic Syndromes. Neurol Clin Pract. 2024 Jun;14(3):e200277. doi: 10.1212/CPJ.0000000000200277. Epub 2024 May 7. PMID: 38737513; PMCID: PMC11081764.

Abstract

Background and objectives: To provide real-word clinical follow-up data on patients carrying variations of congenital myasthenic syndromes (CMS) and who respond to some innovative drugs.

Methods: Patients recruited from the Neurology Department of the Mustapha Bacha university hospital in Algiers. Treated with innovative drugs, they were monitored and their clinical progress was evaluated on the basis of clinical arguments suggestive of CMSs, but also para clinical arguments (electromyography and genetic study).

Results: Six patients carrying different mutations in different genes of CMSs were studied. They had different pathophysiologic profiles (slow or fast channel syndromes, low expressor of receptor). Their therapeutic management was based on innovative drugs, normally indicated in other, non-neurological pathologies. Their outcome was toward a clear clinical improvement.

Discussion: This work relates the interest of proposing treatments (outside of Pyridostigmine) in the management of CMSs. These therapies can greatly modify the prognosis of patients suffering from this orphan disease.

Classification of evidence: This study provides Class IV evidence that for patients with congenital myasthenic syndromes, some innovative treatments are effective.

Kao JC, Milone M, Selcen D, Shen XM, Engel AG, Liewluck T. Congenital myasthenic syndromes in adult neurology clinic: A long road to diagnosis and therapy. Neurology. 2018 Nov 6;91(19):e1770-e1777. doi: 10.1212/WNL.0000000000006478. Epub 2018 Oct 5. PMID: 30291185; PMCID: PMC6251603.

Abstract

Objective: To investigate the diagnostic challenges of congenital myasthenic syndromes (CMS) in adult neuromuscular practice.

Methods: We searched the Mayo Clinic database for patients with CMS diagnosed in adulthood in the neuromuscular clinic between 2000 and 2016. Clinical, laboratory, and electrodiagnostic data were reviewed.

Results: We identified 34 patients with CMS, 30 of whom had a molecular diagnosis (14 DOK7, 6 RAPSN, 2 LRP4, 2 COLQ, 2 slow-channel syndrome, 1 primary acetylcholine receptor deficiency, 1 AGRN, 1 GFPT1, and 1 SCN4A). Ophthalmoparesis was often mild and present in 13 patients. Predominant limb-girdle weakness occurred in 19 patients. Two patients had only ptosis. Age at onset ranged from birth to 39 years (median 5 years). The median time from onset to diagnosis was 26 years (range 4-56 years). Thirteen patients had affected family members. Fatigable weakness was present when examined. Creatine kinase was elevated in 4 of 23 patients (range 1.2-4.2 times the upper limit of normal). Repetitive nerve stimulation revealed a decrement in 30 patients. Thirty-two patients were previously misdiagnosed with seronegative myasthenia gravis (n = 16), muscle diseases (n = 15), weakness of undetermined cause (n = 8), and others (n = 4). Fifteen patients received immunotherapy or thymectomy without benefits. Fourteen of the 25 patients receiving pyridostigmine did not improve or worsen.

Conclusion: Misdiagnosis occurred in 94% of the adult patients with CMS and causes a median diagnostic delay of nearly 3 decades from symptom onset. Seronegative myasthenia gravis and muscle diseases were the 2 most common misdiagnoses, which led to treatment delay and unnecessary exposure to immunotherapy, thymectomy, or muscle biopsy.