{"title":"Concurrent Carpal Tunnel Syndrome and Recurrent Motor Branch of the Median Nerve Compression: A Diagnostic Complexity.","authors":"Özgür Zeliha Karaahmet, Egemen Ayhan, Yasemin Tombak Yıldızkan, Ebru Umay","doi":"10.1097/CND.0000000000000474","DOIUrl":"10.1097/CND.0000000000000474","url":null,"abstract":"","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"148-150"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000477
Shin J Oh
Objectives: In 2015, a new term "nodopathy" was introduced to represent a group of neuropathy because of autoantibodies at the node of Ranvier and paranodal area. This review was conducted to highlight the electrophysiologic characteristics of acute and chronic nodopathies by the newly introduced term: "nodal conduction block (CB); CB without temporal dispersion or slow nerve conduction velocity" and by introducing a new term: "internodal CB; CB with temporal dispersion or/and slow nerve conduction velocity".
Methods: Through PubMed searches, 23 cases of acute (<4 weeks of neuropathy) nodopathy and 12 cases of chronic (>4 weeks of neuropathy) nodopathy are identified. Two other required inclusion criteria are positive nodal antibody test and detailed nerve conduction data with or without figure. All existing data were analyzed to see whether these cases had nodal or internodal CB.
Results: Among 23 cases of acute nodopathy, 11 had nodal CB, 9 internodal CB, and 3 mixed CB. Thus, nodal CB was observed in 61% of acute nodopathy cases and internodal CB in 52% of acute nodopathy cases. Among 12 cases of chronic nodopathy, all 12 had internodal CB.
Conclusions: Nodal CB is the nerve conduction characteristic of acute nodopathy, but internodal CB does not rule out acute nodopathy. Internodal CB is the nerve conduction characteristic of chronic nodopathy.
{"title":"Nodal Conduction Block and Internodal Conduction Block in Nodopathy.","authors":"Shin J Oh","doi":"10.1097/CND.0000000000000477","DOIUrl":"10.1097/CND.0000000000000477","url":null,"abstract":"<p><strong>Objectives: </strong>In 2015, a new term \"nodopathy\" was introduced to represent a group of neuropathy because of autoantibodies at the node of Ranvier and paranodal area. This review was conducted to highlight the electrophysiologic characteristics of acute and chronic nodopathies by the newly introduced term: \"nodal conduction block (CB); CB without temporal dispersion or slow nerve conduction velocity\" and by introducing a new term: \"internodal CB; CB with temporal dispersion or/and slow nerve conduction velocity\".</p><p><strong>Methods: </strong>Through PubMed searches, 23 cases of acute (<4 weeks of neuropathy) nodopathy and 12 cases of chronic (>4 weeks of neuropathy) nodopathy are identified. Two other required inclusion criteria are positive nodal antibody test and detailed nerve conduction data with or without figure. All existing data were analyzed to see whether these cases had nodal or internodal CB.</p><p><strong>Results: </strong>Among 23 cases of acute nodopathy, 11 had nodal CB, 9 internodal CB, and 3 mixed CB. Thus, nodal CB was observed in 61% of acute nodopathy cases and internodal CB in 52% of acute nodopathy cases. Among 12 cases of chronic nodopathy, all 12 had internodal CB.</p><p><strong>Conclusions: </strong>Nodal CB is the nerve conduction characteristic of acute nodopathy, but internodal CB does not rule out acute nodopathy. Internodal CB is the nerve conduction characteristic of chronic nodopathy.</p>","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"163-170"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000463
Carolyn Black, Haibi Cai, Aliya Shabbir, Leo H Wang
Objective: Ultrasound studies in inclusion body myositis (IBM) have reported a characteristic pattern of increased echointensity in the flexor digitorum profundus (FDP) with relative sparing of the flexor carpi ulnaris (FCU). We examined the relationship between echointensity of the FDP and FCU muscles and hand strength or patient-reported outcomes (PROs).
Methods: A total of 15 patients with IBM were recruited. Ultrasound images of the FDP and FCU muscles were obtained by a point-of-care ultrasound and graded using the modified Heckmatt score. Hand grip and neutral pinch strength were measured by dynamometry. PROs were assessed by the IBM Upper Extremity Function Scale.
Results: FDP and/or FCU modified Heckmatt score showed a significant relationship with grip, neutral pinch strength, and PROs.
Conclusions: Point-of-care ultrasound examination of the forearm may serve as an extension of the neuromuscular examination. The semi-qualitative echointensity rating based on modified Heckmatt score seems to correlate well with the objective strength measurement and PROs.
目的:包涵体肌炎(IBM)的超声研究报告了一种特征性模式,即拇屈肌(FDP)的回声密度增加,而尺桡侧屈肌(FCU)的回声密度相对较低。我们研究了 FDP 和 FCU 肌肉的回声密度与手部力量或患者报告结果(PROs)之间的关系:方法:共招募了 15 名 IBM 患者。方法:共招募了 15 名 IBM 患者,通过床旁超声检查获得了 FDP 和 FCU 肌肉的超声图像,并使用改良的 Heckmatt 评分进行了分级。通过测力计测量手部握力和中立捏力。通过IBM上肢功能量表对PROs进行评估:结果:FDP 和/或 FCU 改良 Heckmatt 评分与握力、中性捏力和 PROs 有显著关系:结论:前臂的定点超声检查可作为神经肌肉检查的延伸。基于改良 Heckmatt 评分的半定性回声强度评级似乎与客观力量测量和 PROs 有很好的相关性。
{"title":"Relationship Between Hand Function and Handheld Ultrasound Imaging in Inclusion Body Myositis.","authors":"Carolyn Black, Haibi Cai, Aliya Shabbir, Leo H Wang","doi":"10.1097/CND.0000000000000463","DOIUrl":"10.1097/CND.0000000000000463","url":null,"abstract":"<p><strong>Objective: </strong>Ultrasound studies in inclusion body myositis (IBM) have reported a characteristic pattern of increased echointensity in the flexor digitorum profundus (FDP) with relative sparing of the flexor carpi ulnaris (FCU). We examined the relationship between echointensity of the FDP and FCU muscles and hand strength or patient-reported outcomes (PROs).</p><p><strong>Methods: </strong>A total of 15 patients with IBM were recruited. Ultrasound images of the FDP and FCU muscles were obtained by a point-of-care ultrasound and graded using the modified Heckmatt score. Hand grip and neutral pinch strength were measured by dynamometry. PROs were assessed by the IBM Upper Extremity Function Scale.</p><p><strong>Results: </strong>FDP and/or FCU modified Heckmatt score showed a significant relationship with grip, neutral pinch strength, and PROs.</p><p><strong>Conclusions: </strong>Point-of-care ultrasound examination of the forearm may serve as an extension of the neuromuscular examination. The semi-qualitative echointensity rating based on modified Heckmatt score seems to correlate well with the objective strength measurement and PROs.</p>","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"115-121"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000470
Abena Kwegyir-Aggrey, James B Meiling, Nicholas J Miller, Rachana K Gandhi Mehta
{"title":"An Unusual Presentation of MuSK-Myasthenia Gravis With Bladder Incontinence Responding to Rituximab Treatment: A Case Report and Review of the Literature.","authors":"Abena Kwegyir-Aggrey, James B Meiling, Nicholas J Miller, Rachana K Gandhi Mehta","doi":"10.1097/CND.0000000000000470","DOIUrl":"10.1097/CND.0000000000000470","url":null,"abstract":"","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"145-146"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140040537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000466
Fulvio A Scorza, Josef Finsterer
{"title":"Axonal Neuropathy in Severe SARS-CoV-2 Infections Is Multicausal.","authors":"Fulvio A Scorza, Josef Finsterer","doi":"10.1097/CND.0000000000000466","DOIUrl":"10.1097/CND.0000000000000466","url":null,"abstract":"","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"142-144"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000465
Aditya Vijayakrishnan Nair, Madhavi Kandagaddala, Ajith Sivadasan, A T Prabhakar, Shalini Nair, Vivek Mathew, Sanjith Aaron, Mathew Alexander
Objectives: Neuromuscular disorders could have respiratory involvement early or late into illness. Rarely, patients may present with a hypercapnic respiratory failure (with minimal motor signs) unmasking an underlying disease. There are hardly any studies which have addressed the spectrum and challenges involved in management of this subset, especially in the real-world scenario.
Methods: A retrospective study comprising consecutive patients hospitalized with hypercapnic respiratory failure as the sole/dominant manifestation. The clinical-electrophysiological spectrum, phrenic conductions, diaphragm thickness, and outcomes were analyzed.
Results: Twenty-seven patients were included, the mean age was 47.29 (SD 15.22) years, and the median duration of respiratory symptoms was 2 months (interquartile range [IQR] 1-4). Orthopnea was present in 23 patients (85.2%) and encephalopathy in 8 patients (29.6%). Phrenic nerve latencies and amplitudes were abnormal in 83.3% and 95.6%, respectively. Abnormal diaphragm thickness was noted in 78.5%. Based on a comprehensive electrophysiological strategy and paraclinical tests, an etiology was established in all. Reversible etiologies were identified in 17 patients (62.9%). These included myasthenia gravis (anti-AChR and MuSK), inflammatory myopathy, riboflavin transporter deficiency neuronopathy, Pompe disease, bilateral phrenic neuritis, and thyrotoxicosis. Respiratory onset motor neuron disease was diagnosed in 8 patients (29.6%). Despite diaphragmatic involvement, a functional respiratory recovery was noted at discharge (45%) and last follow-up (60%). Predictors for good outcomes included female sex, normal nerve conductions, and recent-onset respiratory symptoms.
Discussion: A good functional recovery was noted in most of the patients including respiratory onset motor neuron disease. A systematic algorithmic approach helps in proper triaging, early diagnosis, and treatment. Clinical and electrodiagnostic challenges and observations from a tertiary care referral center are discussed.
{"title":"\"De Novo\" Hypercapnic Respiratory Failure Unmasking Neuromuscular Disorders: Experiences From a Tertiary Care Center and Review of Literature.","authors":"Aditya Vijayakrishnan Nair, Madhavi Kandagaddala, Ajith Sivadasan, A T Prabhakar, Shalini Nair, Vivek Mathew, Sanjith Aaron, Mathew Alexander","doi":"10.1097/CND.0000000000000465","DOIUrl":"10.1097/CND.0000000000000465","url":null,"abstract":"<p><strong>Objectives: </strong>Neuromuscular disorders could have respiratory involvement early or late into illness. Rarely, patients may present with a hypercapnic respiratory failure (with minimal motor signs) unmasking an underlying disease. There are hardly any studies which have addressed the spectrum and challenges involved in management of this subset, especially in the real-world scenario.</p><p><strong>Methods: </strong>A retrospective study comprising consecutive patients hospitalized with hypercapnic respiratory failure as the sole/dominant manifestation. The clinical-electrophysiological spectrum, phrenic conductions, diaphragm thickness, and outcomes were analyzed.</p><p><strong>Results: </strong>Twenty-seven patients were included, the mean age was 47.29 (SD 15.22) years, and the median duration of respiratory symptoms was 2 months (interquartile range [IQR] 1-4). Orthopnea was present in 23 patients (85.2%) and encephalopathy in 8 patients (29.6%). Phrenic nerve latencies and amplitudes were abnormal in 83.3% and 95.6%, respectively. Abnormal diaphragm thickness was noted in 78.5%. Based on a comprehensive electrophysiological strategy and paraclinical tests, an etiology was established in all. Reversible etiologies were identified in 17 patients (62.9%). These included myasthenia gravis (anti-AChR and MuSK), inflammatory myopathy, riboflavin transporter deficiency neuronopathy, Pompe disease, bilateral phrenic neuritis, and thyrotoxicosis. Respiratory onset motor neuron disease was diagnosed in 8 patients (29.6%). Despite diaphragmatic involvement, a functional respiratory recovery was noted at discharge (45%) and last follow-up (60%). Predictors for good outcomes included female sex, normal nerve conductions, and recent-onset respiratory symptoms.</p><p><strong>Discussion: </strong>A good functional recovery was noted in most of the patients including respiratory onset motor neuron disease. A systematic algorithmic approach helps in proper triaging, early diagnosis, and treatment. Clinical and electrodiagnostic challenges and observations from a tertiary care referral center are discussed.</p>","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"122-131"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-01DOI: 10.1097/CND.0000000000000472
Peyton J Murin, Ivana Massabki, Jafar Kafaie
Objectives: Small fiber neuropathy (SFN) is a subtype of painful neuropathies defined by dysfunction of the Aδ and unmyelinated C fibers. It presents with both neuropathic pain and dysautonomia symptoms, posing a significant diagnostic and therapeutic challenge. To address this challenge, research has been conducted to identify autoantibodies and define their association with phenotypes.
Methods: Eleven cases of anti-plexin-D1 seropositive SFN were reviewed, along with relevant literature, in attempt to better define anti-plexin-D1 SFN demographics, symptoms, associated medical conditions, and therapeutics.
Results: Anti-plexin-D1 SFN typically presents in female patients, with neuropathic pain, normal skin biopsy findings, and normal nerve conduction studies. Anti-plexin-D1 shows an association with concurrent chronic pain, with almost half of the patients undergoing an interventional procedure.
Conclusions: Anti-plexin-D1 represents a unique subgroup of SFN, defined by distinct demographics, phenotype, biopsy findings, and therapeutic management.
目的:小纤维神经病(SFN)是疼痛性神经病的一种亚型,由 Aδ 纤维和无髓鞘 C 纤维的功能障碍所定义。它同时表现出神经性疼痛和自主神经功能障碍症状,给诊断和治疗带来了巨大挑战。为应对这一挑战,研究人员已开始识别自身抗体并确定其与表型的关联:方法:研究人员回顾了11例抗plexin-D1血清阳性SFN病例以及相关文献,试图更好地界定抗plexin-D1 SFN的人口统计学特征、症状、相关医疗条件和治疗方法:结果:抗plexin-D1 SFN通常出现在女性患者身上,伴有神经性疼痛、正常的皮肤活检结果和正常的神经传导研究。抗plexin-D1与并发慢性疼痛有关,近一半患者接受了介入治疗:结论:抗plexin-D1代表了一种独特的SFN亚群,其人口统计学、表型、活检结果和治疗方法各不相同。
{"title":"Anti-Plexin-D1 Seropositive Small Fiber Neuropathy: Clinical Phenotype, Demographics, and Literature Review.","authors":"Peyton J Murin, Ivana Massabki, Jafar Kafaie","doi":"10.1097/CND.0000000000000472","DOIUrl":"10.1097/CND.0000000000000472","url":null,"abstract":"<p><strong>Objectives: </strong>Small fiber neuropathy (SFN) is a subtype of painful neuropathies defined by dysfunction of the Aδ and unmyelinated C fibers. It presents with both neuropathic pain and dysautonomia symptoms, posing a significant diagnostic and therapeutic challenge. To address this challenge, research has been conducted to identify autoantibodies and define their association with phenotypes.</p><p><strong>Methods: </strong>Eleven cases of anti-plexin-D1 seropositive SFN were reviewed, along with relevant literature, in attempt to better define anti-plexin-D1 SFN demographics, symptoms, associated medical conditions, and therapeutics.</p><p><strong>Results: </strong>Anti-plexin-D1 SFN typically presents in female patients, with neuropathic pain, normal skin biopsy findings, and normal nerve conduction studies. Anti-plexin-D1 shows an association with concurrent chronic pain, with almost half of the patients undergoing an interventional procedure.</p><p><strong>Conclusions: </strong>Anti-plexin-D1 represents a unique subgroup of SFN, defined by distinct demographics, phenotype, biopsy findings, and therapeutic management.</p>","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 3","pages":"132-140"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140029165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1097/CND.0000000000000460
Mustafa Al-Chalabi, Prajwal Hegde, Sara R Moore, Yasmeen Abouainain, Myles Keener, Hira Parvez, Jeremy Eid, Sidra Saleem, Ajaz Sheikh
<p><strong>Objectives: </strong>Isaac syndrome (IS) is a condition characterized by peripheral nerve hyperexcitability caused by voltage-gated potassium channel (VGKC)-complex antibodies. Muscle twitching, stiffness, hypertrophy, and dysautonomic characteristics, such as hyperhidrosis, are common manifestations. The syndrome can be autoimmune or paraneoplastic, with thymoma being a common cause of paraneoplastic IS. Furthermore, this condition could be handed down from one generation to another. However, there is limited information regarding outcomes, relapses, associated syndromes, associated malignancies (other than thymoma), and treatment options. Despite its rarity, there remains a need for effective management strategies for patients with IS. To address this gap, we conducted a systematic review to summarize the most common and effective treatments of IS in immunomodulatory agents and symptomatic medications, as well as to describe outcomes, relapses, and associated malignancies. Altogether, this review serves to guide clinical practice recommendations for IS and highlight areas for further research.</p><p><strong>Methods: </strong>We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol to conduct a systematic review of cases reposted through the PubMed and Google Scholar databases. The terms "Isaac Syndrome" and "Acquired Neuromyotonia" were used. The Joanna Briggs Institute's critical appraisal tool was used to evaluate the quality of the included studies.</p><p><strong>Results: </strong>We identified 61 case reports and 4 case series, comprising a total of 70 patients with IS (mean age at onset: 42.5 ± 18 years, and 69% were males). Fourteen cases reported relapses. Thymoma was the most common malignancy associated with IS, followed by lymphoma. Among various serum antibodies, voltage-gated potassium channel-complex antibodies were the most reported antibodies elevated in IS (reported in 38 patients and elevated in 21 patients [55.2%]), followed by acetylcholine ganglionic receptor antibodies, which were reported in 30% of patients (n = 21) and were elevated in 5 cases. The most common electromyography findings were myokymic discharges (n = 22), followed by fasciculations (n = 21) and neuromyotonia (n = 19). For treatment, combining anticonvulsants such as carbamazepine with immunotherapy therapy showed the best results in controlling the symptoms. Among immunotherapy therapies, the combination of plasma exchange plus intravenous high-dose steroids achieved the best results in the acute treatment of IS ([n = 6], with improvement noted in 83.3% [n = 5] of cases). Among the symptomatic treatments with anticonvulsants, carbamazepine was the most efficacious anticonvulsant in treatment of IS, with an average effective dosing of 480 mg/day (carbamazepine was used in 32.3% of acute treatment strategies [n = 23], with improvement noted in 73.9% [n = 17] of cases).</p><p><strong>Conclusions: </strong>IS a rare neu
{"title":"Systematic Review of the Clinical Characteristics and Management of Isaac Syndrome.","authors":"Mustafa Al-Chalabi, Prajwal Hegde, Sara R Moore, Yasmeen Abouainain, Myles Keener, Hira Parvez, Jeremy Eid, Sidra Saleem, Ajaz Sheikh","doi":"10.1097/CND.0000000000000460","DOIUrl":"10.1097/CND.0000000000000460","url":null,"abstract":"<p><strong>Objectives: </strong>Isaac syndrome (IS) is a condition characterized by peripheral nerve hyperexcitability caused by voltage-gated potassium channel (VGKC)-complex antibodies. Muscle twitching, stiffness, hypertrophy, and dysautonomic characteristics, such as hyperhidrosis, are common manifestations. The syndrome can be autoimmune or paraneoplastic, with thymoma being a common cause of paraneoplastic IS. Furthermore, this condition could be handed down from one generation to another. However, there is limited information regarding outcomes, relapses, associated syndromes, associated malignancies (other than thymoma), and treatment options. Despite its rarity, there remains a need for effective management strategies for patients with IS. To address this gap, we conducted a systematic review to summarize the most common and effective treatments of IS in immunomodulatory agents and symptomatic medications, as well as to describe outcomes, relapses, and associated malignancies. Altogether, this review serves to guide clinical practice recommendations for IS and highlight areas for further research.</p><p><strong>Methods: </strong>We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol to conduct a systematic review of cases reposted through the PubMed and Google Scholar databases. The terms \"Isaac Syndrome\" and \"Acquired Neuromyotonia\" were used. The Joanna Briggs Institute's critical appraisal tool was used to evaluate the quality of the included studies.</p><p><strong>Results: </strong>We identified 61 case reports and 4 case series, comprising a total of 70 patients with IS (mean age at onset: 42.5 ± 18 years, and 69% were males). Fourteen cases reported relapses. Thymoma was the most common malignancy associated with IS, followed by lymphoma. Among various serum antibodies, voltage-gated potassium channel-complex antibodies were the most reported antibodies elevated in IS (reported in 38 patients and elevated in 21 patients [55.2%]), followed by acetylcholine ganglionic receptor antibodies, which were reported in 30% of patients (n = 21) and were elevated in 5 cases. The most common electromyography findings were myokymic discharges (n = 22), followed by fasciculations (n = 21) and neuromyotonia (n = 19). For treatment, combining anticonvulsants such as carbamazepine with immunotherapy therapy showed the best results in controlling the symptoms. Among immunotherapy therapies, the combination of plasma exchange plus intravenous high-dose steroids achieved the best results in the acute treatment of IS ([n = 6], with improvement noted in 83.3% [n = 5] of cases). Among the symptomatic treatments with anticonvulsants, carbamazepine was the most efficacious anticonvulsant in treatment of IS, with an average effective dosing of 480 mg/day (carbamazepine was used in 32.3% of acute treatment strategies [n = 23], with improvement noted in 73.9% [n = 17] of cases).</p><p><strong>Conclusions: </strong>IS a rare neu","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 2","pages":"94-106"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92156920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract: Immune checkpoint inhibitors used to treat malignancies may lead to various immune-related adverse events (irAEs) including conditions such as myositis and myasthenia gravis (MG). Here, we describe 2 cases of myositis treated effectively with therapeutic plasma exchange (PLEX). A 64-year-old man with thymic cancer developed leg weakness and dyspnea 1 month after the second dose of nivolumab with moderate weakness in proximal and distal muscles, with elevated creatine kinase levels. Another 77-year-old man with Stage IIIB squamous cell carcinoma of the lung developed progressive proximal muscle weakness and became nonambulatory after cycle 2 of durvalumab with persistently high creatine kinase levels despite prednisone treatment. Electrophysiology revealed irritative myopathy without evidence of neuromuscular junction dysfunction and MG antibody testing was nonrevealing. With PLEX, both patients noticed rapid improvement in strength. PLEX in conjunction with other immunosuppressive agents can result in rapid improvement in irAE-myositis even in patients without associated MG.
{"title":"Plasma Exchange in Patients With Myositis due to Immune Checkpoint Inhibitor Therapy.","authors":"Nakul Katyal, Tamiko R Katsumoto, Kavitha J Ramachandran, Muharrem Yunce, Srikanth Muppidi","doi":"10.1097/CND.0000000000000457","DOIUrl":"10.1097/CND.0000000000000457","url":null,"abstract":"<p><strong>Abstract: </strong>Immune checkpoint inhibitors used to treat malignancies may lead to various immune-related adverse events (irAEs) including conditions such as myositis and myasthenia gravis (MG). Here, we describe 2 cases of myositis treated effectively with therapeutic plasma exchange (PLEX). A 64-year-old man with thymic cancer developed leg weakness and dyspnea 1 month after the second dose of nivolumab with moderate weakness in proximal and distal muscles, with elevated creatine kinase levels. Another 77-year-old man with Stage IIIB squamous cell carcinoma of the lung developed progressive proximal muscle weakness and became nonambulatory after cycle 2 of durvalumab with persistently high creatine kinase levels despite prednisone treatment. Electrophysiology revealed irritative myopathy without evidence of neuromuscular junction dysfunction and MG antibody testing was nonrevealing. With PLEX, both patients noticed rapid improvement in strength. PLEX in conjunction with other immunosuppressive agents can result in rapid improvement in irAE-myositis even in patients without associated MG.</p>","PeriodicalId":39645,"journal":{"name":"Journal of Clinical Neuromuscular Disease","volume":"25 2","pages":"89-93"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10645099/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92156917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}