Prevalence, Mortality, and Cause of Death in Charcot-Marie-Tooth Disease in Korea: A Nationwide, Population-Based Study

Neuromuscular monitoring of a patient with Charcot-Marie-Tooth disease; which monitoring technique is adequate? - A case report and literature review

BACKGROUND

Charcot-Marie-Tooth disease (CMTD) is a hereditary polyneuropathy associated with a life-threatening risk of pulmonary complications.

CASE

A 61-year-old male with CMTD for 40 years was admitted for the drainage of an abscess in his left ankle. Total intravenous anesthesia was administered, and an electromyography device was attached to the hand for neuromuscular monitoring; however, the response was not measured. Kinemyography and acceleromyography devices were attached to both hands, and responses were obtained. After neuromuscular blockade (NMB) with rocuronium 0.6 mg/kg, the train-of-four (TOF) response on kinemyography was normally measured, but the post-tetanic count on acceleromyography consistently showed 0 during anesthesia. Sugammadex 200 mg was injected to reverse the NMB. After 5 min, the TOF ratios for kinemyography and acceleromyography exceeded 90%. The patient recovered without any complications.

CONCLUSIONS

For CMTD patients, acceleromyography or kinemyography is superior to electromyography, and sugammadex can be used to reverse NMB successfully.

Prevalence of Neuromuscular Diseases in Young South Korean Males; A Korean Military Manpower Administration and Medical Command Data-Based Study

BACKGROUND AND PURPOSE

All young males in South Korea must undergo a physical examination for their participation in military service. We aimed to determine the prevalence rate (PR) of various neuromuscular diseases in young South Korean males using the data of exempted patients and soldiers.

METHODS

The number of males exempted based on specific items of physical examination corresponding to neuromuscular disease during 2011-2020 were obtained from the records of the Military Manpower Administration. The list of enlisted soldier patients who were discharged from military service due to neuromuscular diseases during 2011-2020 was obtained from the Armed Forces Medical Command, and their medical records were reviewed.

RESULTS

The PR of neuromuscular diseases was calculated among 948 identified males: 713 exempted males and 235 soldiers. The PRs of overall hereditary neuropathies, Hirayama disease (HD), myasthenia gravis (MG), and inherited muscle diseases in South Korean males in their early 20s were 8.34 (95% confidence interval [CI], 7.39-9.30), 5.54 (95% CI, 4.76-6.32), 2.97 (95% CI, 2.40-3.55), and 10.38 (95% CI, 9.31-11.46) per 100,000 persons, respectively. Among the enlisted soldiers, hereditary neuropathy with liability to pressure palsy was the most common neuromuscular disease, with a prevalence among the enlisted soldiers of 3.11 (95% CI, 2.42-3.80) per 100,000 persons. Myotonic dystrophy was the most prevalent myopathy, followed by facioscapulohumeral muscular dystrophy.

CONCLUSIONS

The 10-year PRs of hereditary polyneuropathies, HD, MG, and inherited muscle diseases in young South Korean males have been reported. These data could be valuable to understanding each neuromuscular disease in the young male population of South Korea.

Clinical genetics of Charcot-Marie-Tooth disease

Recent research in the field of inherited peripheral neuropathies (IPNs) such as Charcot-Marie-Tooth (CMT) disease has helped identify the causative genes provided better understanding of the pathogenesis, and unraveled potential novel therapeutic targets. Several reports have described the epidemiology, clinical characteristics, molecular pathogenesis, and novel causative genes for CMT/IPNs in Japan. Based on the functions of the causative genes identified so far, the following molecular and cellular mechanisms are believed to be involved in the causation of CMTs/IPNs: myelin assembly, cytoskeletal structure, myelin-specific transcription factor, nuclear related, endosomal sorting and cell signaling, proteasome and protein aggregation, mitochondria-related, motor proteins and axonal transport, tRNA synthetases and RNA metabolism, and ion channel-related mechanisms. In this article, we review the epidemiology, genetic diagnosis, and clinicogenetic characteristics of CMT in Japan. In addition, we discuss the newly identified novel causative genes for CMT/IPNs in Japan, namely MME and COA7. Identification of the new causes of CMT will facilitate in-depth characterization of the underlying molecular mechanisms of CMT, leading to the establishment of therapeutic approaches such as drug development and gene therapy.

A meta-analysis on the prevalence of Charcot-Marie-Tooth disease and related inherited peripheral neuropathies

BACKGROUND

Charcot-Marie-Tooth disease and related inherited peripheral neuropathies (CMT&RIPNs) brings great suffering and heavy burden to patients, but its global prevalence rates have not been well described.

METHODS

We searched major English and Chinese databases for studies reporting the prevalence of CMT&RIPNs from the establishment of the databases to September 26, 2022. Based on the age, gender, study design, study region, and disease subtype, the included studies were correspondingly synthesized for meta-analyses on the overall prevalence and/or the subgroup analyses by using pool arcsine transformed proportions in the random-effects model.

RESULTS

Of the finally included 31 studies, 21 studied the whole age population and various types of CMT&RIPNs, and the others reported specific disease subtype(s) or adult or non-adult populations. The pooled prevalence was 17.69/100,000 (95% CI 12.32-24.33) for the whole age population and significantly higher for CMT1 [10.61/100,000 (95% CI 7.06-14.64)] than for other subtypes (P' < 0.001). Without statistical significance, the prevalence seemed higher in those aged ≥ 16 or 18 years (21.02/100,000) than in those aged < 16 years (16.13/100,000), in males (22.50/100,000) than in females (17.95/100,000), and in Northern Europe (30.97/100,000) than in other regions.

CONCLUSION

CMT&RIPNs are relatively more prevalent as CMT1 in the disease subtypes, and probably prevalent in older ages, males, and Northern Europe. More studies on the epidemiological characteristics of CMT&RIPNs with well-defined diagnosis criteria are needed to improve the prevalence evaluation and to arouse more attention to health care support.

Review of general and head and neck/oral and maxillofacial features of Charcot-Marie-Tooth disease and dental management considerations

Charcot-Marie-Tooth disease (CMTD) is an uncommon progressive neuromuscular disorder of the peripheral nervous system and primarily leads to distal extremity weakness and sensory deficits. Frequently, affected patients manifest pes cavus, drop foot, and digit contractures that may pose significant challenges in ambulation and grasping objects. Although there are numerous articles of this syndrome in the medical literature, there is a limited number of dental publications. The objective of this article is to review the general and head and neck/oral and maxillofacial features of CMTD. General guidelines for dental management are also provided.

Incidence, Disability, and Mortality in Patients With Guillain-Barré Syndrome in Korea: A Nationwide Population-Based Study

BACKGROUND AND PURPOSE

This study aimed to identify the epidemiological features of Guillain-Barré syndrome (GBS) in the Korean population.

METHODS

Patients with GBS were defined as those who were hospitalized with a primary diagnostic code of G61.0 on the Korean Classification of Disease in a department of neurology, rehabilitation medicine, or pediatrics. We evaluated the incidence and prevalence of GBS as well as physical disability, mortality, and cause of death in patients with GBS from 2002 to 2018 in the Korean population using the Korean National Health Insurance Service database.

RESULTS

We identified 11,146 patients with GBS. The ratio of males to females was 1.48. The age-adjusted incidence rate per 100,000 persons increased steadily from 0.84 in 2002 to 1.68 in 2018, as did the age-adjusted prevalence rate per 100,000 persons, from 0.77 to 15.62. The incidence and prevalence of GBS increased with age, peaking at 70-79 years. Among 10,114 patients without physical disability at the time of GBS being diagnosed, 502 (5.0%) patients had moderate disability and 526 (5.2%) had severe disability by the end of the study period. A total of 1,221 (11.0%) patients with GBS died during the mean follow-up period of 17 years (2002-2019). There were 144 (1.3%) in-hospital deaths.

CONCLUSIONS

This was the first nationwide epidemiological study of patients with GBS covering the entire population including patients of all ages in the Republic of Korea. We have revealed the seasonality of admissions, disability, and long-term mortality rates in patients with GBS.

Recent Advances in Drosophila Models of Charcot-Marie-Tooth Disease

Charcot-Marie-Tooth disease (CMT) is one of the most common inherited peripheral neuropathies. CMT patients typically show slowly progressive muscle weakness and sensory loss in a distal dominant pattern in childhood. The diagnosis of CMT is based on clinical symptoms, electrophysiological examinations, and genetic testing. Advances in genetic testing technology have revealed the genetic heterogeneity of CMT; more than 100 genes containing the disease causative mutations have been identified. Because a single genetic alteration in CMT leads to progressive neurodegeneration, studies of CMT patients and their respective models revealed the genotype-phenotype relationships of targeted genes. Conventionally, rodents and cell lines have often been used to study the pathogenesis of CMT. Recently, Drosophila has also attracted attention as a CMT model. In this review, we outline the clinical characteristics of CMT, describe the advantages and disadvantages of using Drosophila in CMT studies, and introduce recent advances in CMT research that successfully applied the use of Drosophila, in areas such as molecules associated with mitochondria, endosomes/lysosomes, transfer RNA, axonal transport, and glucose metabolism.