Crisis Miasténica: Reporte de Caso y Revisión de la Literatura / Myasthenic Crisis: Case Report and Literature Review

Introducción. La crisis miasténica es la complicación más grave que sufren los pacientes con Miastenia Gravis. Esta enfermedad se caracteriza clínicamente por debilidad muscular generalizada, que particularmente mejora con el reposo y empeora con el ejercicio debido al agotamiento de la conducción nerviosa a nivel post sináptico. El manejo de la crisis miasténica tiene como piedra angular tratar la causa desencadenante, así como utilizar los fármacos de acción rápida y los descritos en la literatura para enfrentar este escenario, como la plasmaféresis, inmunoglobulinas o terapia biológica. Además, es crucial tener un adecuado manejo desde el punto de vista ventilatorio manteniendo la protección pulmonar y sobre todo diafragmática, con las herramientas disponibles en la actualidad al lado de la cama del paciente. Asimismo, el weaning o destete del ventilador mecánico debe llevarse a cabo de manera objetiva y bajo evaluaciones específicas para lograr un desenlace optimo.

Introduction. Myasthenic crisis is the most serious complication suffered by patients with Myasthenia Gravis. This disease is clinically characterized by generalized muscle weakness, which particularly improves with rest and worsens with exercise due to depletion of nerve conduction at the post-synaptic level. The cornerstone of managing myasthenic crisis is treating the triggering cause, as well as using fast-acting drugs and interventions described in the literature to deal with this scenario, such as plasmapheresis, immunoglobulins, or biological therapy. In addition, it is imperative to ensure adecuate management from the ventilatory perspective, preserving lung function and safeguarding the diaphragm with the tools currently available at the patient's bedside. Likewise, weaning from the mechanical ventilator must be conducted objectively and guided by specific evaluations to achieve an optimal outcome.

Application of new surgical clinical classification and staging of myasthenia gravis in the perioperative period / 中国胸心血管外科临床杂志

@#Objective     To exploring the effectiveness of perioperative application of new surgical clinical classification and staging for myasthenia gravis (MG) in reducing the incidence of postoperative myasthenic crisis (MC). Methods     The clinical data of patients with generalized MG admitted to the Comprehensive Treatment Center for Myasthenia Gravis of Henan Provincial People’s Hospital from January 2018 to June 2022 were retrospectively analyzed, who were scored with myasthenia gravis-activities of daily living (MG-ADL) score and quantification of the myasthenia gravis (QMG) score at the first visit, 1 day before surgery, and 3 days after surgery. The patients were divided into a group A (typeⅡ) and a group B (typeⅢ+Ⅳ+Ⅴ) by the new surgical clinical classification and staging of MG according to the disease progression process, and all patients underwent expanded thoracoscopic thymus (tumor) resection after medication and other interventions to control symptoms in remission or stability. The incidence of MC and the efficiency rate after surgery were analyzed. The normal distribution method and percentile method were used to calculate the unilateral 95% reference range of the QMG score and MG-ADL score. Results     Finally 126 patients were enrolled, including 62 males and 64 females, aged 13-71 years, with an average age of 46.00±13.00 years. There were 95 patients in the group A and 31 patients in the group B, and the differences of the preoperative baseline data between the two groups were not statistically significant (P>0.05). The incidence of postoperative MC was 1.05% (1/95) in the group A and 3.23%(1/31) in the group B (P>0.05). The effective one-sided 95% reference range of the QMG score and MG-ADL score 1 day before surgery was 0-7.75 and 0-5.00, and there was no postoperative death in both groups. Conclusion     The new surgical clinical classification and staging of MG can guide the timing of surgery, which can benefit patients undergoing surgery for MG and greatly reduce the incidence of postoperative MC.

Perioperative Management of Myasthenia Gravis Patient for off Pump Coronary Artery Bypass Surgery and Thymectomy

Myasthenia gravis (MG) is an autoimmune disorder characterized by antibody?mediated immunologic reaction striking the acetylcholine receptors. The anesthesia concerns for patients with MG include the disease state, drug interactions, and the anesthetic medications particularly the neuromuscular blocking agents (NMBAs). The anesthesia management in these patients is meticulous and requires appropriate execution of knowledge. Besides, such patient for off?pump coronary artery bypass surgery is quite uncommon; hence, we report this case.

Analysis of risk factors of myasthenia crisis after thymectomy in patients with myasthenia gravis / 中国胸心血管外科临床杂志

@#Objective    To analyze the risk factors of myasthenia gravis crisis after thymectomy with myasthenia gravis (MG). Methods    Sixty-five myasthenia gravis patients who had myasthenia crisis after thymectomy in Xuanwu Hospital, Capital Medical University from June 2006 to June 2019 were retrospectively enrolled, including 31 males and 34 females, aged 15-78 (45.7±17.8) years. The relationship between myasthenia crisis after thymectomy and surgical option, operation time, pathological type, et al. were anylyzed. Results    Operation time and pathological type were the predictive factors of postoperative myasthenic crisis. The area under receiver operating characteristic curve (AUC) of MG type (Osserman) was 0.676, the cut-off value wasⅡB type, the sensitivity was 37.5%, the specificity was 90.5%, and the Youden’s index was 0.280. The AUC of thymoma stage (Masaoka) was 0.682, cut-off value was stageⅡ, sensitivity was 62.5%, specificity was 66.7%, and Youden’s index was 0.292. The AUC of blood loss was 0.658, the cut-off value was 90 mL, the sensitivity was 87.5%, the specificity was 69.6%, and the Youden’s index was 0.304. Conclusion    Preoperative MG classification, pathological type, operation time and blood loss are the risk factors of postoperative myasthenic crisis. Therefore, adequate preoperative preparation, rapid and careful intraoperative operation and active postoperative management can reduce the occurrence of postoperative myasthenic crisis.

Miastenia Gravis: reporte de dos casos y revisión de la literatura / Myasthenia Gravis: two case reports and review

Myasthenia gravis is an acquired autoimmune disorder of the neuromuscular junction characterized by fluctuating weakness and fatigability of skeletal muscles. The diagnosis can be established by clinical and serologic testing, with predominance of autoantibodies against the acetylcholine receptor, and Muscle-specific kinase antibodies. We report two cases of Myasthenia gravis, the first one is a 31 year old patient with a debut of the disease, mainly with bulbar symptoms, and the second one is a 29 year old patient diagnosed with generalized Miasthenia Gravis also mainly with bulbar symptoms with worsening of symptomatology. In this report treatments alternatives and management approaches are discused

Cardiomyopathy in Patients with Myasthenia Gravis Crisis

Myasthenia gravis (MG) crisis is a life-threatening condition characterized by respiratory failure requiring intubation and mechanical ventilation. Cardiac problem in patients with MG crisis is a rare condition, presenting as cardiomyopathy, arrhythmia, heart failure and sudden death. We report two cases that developed arrhythmia and stress-induced cardiomyopathy during MG crisis episodes.

Relationships between the pathology classification, Masaoka clinical stage and postoperation myasthenic crisis in patients of myasthenia gravis with thymoma / 中国医师进修杂志

Objective To investigate the relationships between the pathology classification, Masaoka clinical stage and postoperation myasthenic crisis in patients of myasthenia gravis with thymoma undergoing thymectomy. Methods Clinical records of 56 patients of myasthenia gravis with thymoma from January 2006 to December 2015 who had underwent thymectomy were reviewed retrospectively. The following factors were analyzed to find the relation to the occurrence of myasthenic crisis after thymectomy: WHO pathology classification, Masaoka clinical stage and tumor size. Results Sixteen patients experienced postoperative myasthenic crisis after thymectomy. Statistical analysis revealed that the incidence of postoperative myasthenic crisis in patients with Masaoka Ⅲ stage was significantly higher than that in patients with Masaoka Ⅰ and Ⅱ stage: 39.39% (13/33) vs. 13.04% (3/23), the incidence of postoperative myasthenic crisis in patients with WHO pathology classification B3 and C type was significantly higher than patients with WHO pathology classification B2 type: 50.00% (12/24) vs. 14.29% (4/28), the incidence of postoperative myasthenic crisis in patients with tumor size more than 5 cm was significantly lower than patients with tumor size less than 5 cm: 10/17 vs. 15.38% (6/39), and there were statistical differences (P＜0.05 or＜0.01). Conclusions WHO pathology classification and Masaoka clinical stage are significantly correlated with the occurrence of myasthenia crisis after thymectomy. The patients with MasaokaⅢstage, WHO pathology classification B3 and C type and tumor size more than 5 cm have the risk of postoperative myasthenic crisis after thymectomy. The comprehensive intervention before and after operation can prevent myasthenia crisis.

Strategies to shorten the duration of mechanical ventilation in patients with post-thymectomy myasthenic crisis / 中华胸心血管外科杂志

Objective To identify the clinical and demographical features that may impact the duration of mechanical ventilation(DMV) in the patients with post-thymectomy myasthenic crisis(PTMC).Methods Reviewed the patients who had PTMC from June 2008 to November 2015.Cox proportional hazard regression analysis was used to identify potential prognostic factors that may impact DMV and long-term survival,respectively.One-way ANOVA analysis was used to compare the four groups with continuous variates.Statistical powers were calculated by using XLSTAT.Results In total,seventy patients with PTMC were enrolled.Alcoholic abuse,high MGFA classification and Clavien-Dindo classification were the critical factors that remarkably delayed early extubation.Postoperative lung infection(PLI) as sole complication did not prolong DMV as compared to those without any complication,however,PLI with other more severe complications requiring at least pharmacological treatment seemed to remarkably prolong DMV,as compared to those without any complication.Conclusion Preoperative abstinence,proper treatment of MG and postoperative complications can decrease the incidence of PTMC,shorten the use of ventilator time and improve the prognosis of patients.

Risk factors of myasthenic crisis after thymectomy: a meta analysis / 中华胸心血管外科杂志

Objective To evaluate the risk factors of myasthenic crisis after thymectomy for myasthenia gravis.Methods Meta-analysis was performed to screen risk factors of myasthenic crisis after thymectomy for myasthenia gravis based on 21 associated articles published and carried out using Stata12.0.Results Twenty one studies were identified, including 3 092 patients and 698 patients developed myasthenic crisis after thymectomy.Complicated with thymoma(OR =3.93, 95％ CI 2.37-6.50, P =0.000), Ossermen classification (OR =0.12, 95 ％ CI 0.09-0.17 , P =0.000) , history of preoperative myasthenic crisis (OR =5.36, 95 ％ CI 3.82-7.51, P =0.000) , use steroid hormonea (OR =1.75,95 ％ CI 1.26-2.43, P =0.001) , postopertive lung infection(OR =4.27,95％ CI 1.63-11.18, P =0.003) , operation methods(OR =0.34,95％ CI 0.21-0.56, P =0.000) , the dose of preoperative anticholinesterase drags (OR =0.35, 95 ％ CI 0.18-0.66, P =0.000) ,pulmonary function(OR =0.18, 95％ CI 0.06-0.57, P =0.004), preoperative serum level of anti-acetylcholine receptor antibody(OR =0.06, 95％ CI0.03-0.13, P =0.000)were associated with myasthenic crisis after thymectomy.Gender, course of disease were not associated with myasthenic crisis after thymectomy.Conclusion With thymoma, Ossermen classification, history of preoperative myasthenic crisis, use steroid hormonea, operation methods, the high dose of preoperative anticholinesterase drugs, poor pulmonary function, postopertive lung infection, high preoperative serum level of anti-acetylcholine receptor antibody are risk factors affecting myasthenic crisis after thymectomy.

Update on diagnosis and therapy of juvenile myasthenic crisis / 中国小儿急救医学

Myasthenia gravis is an autoimmune disorder resulting from the production of antibodies against acetylcholine receptors leading to the destruction of the postsynaptic membrane at the neuromuscular junction.Myasthenic crisis is defined as any myasthenia gravis exacerbation necessitating mechanical ventila-tion or post-operation extubation delayed beyond 24 hours because of respiratory weakness.Most patients presenting with myasthenic crisis have an identifiable risk factor.The diagnosis of myasthenic crisis should be suspected in all patients with respiratory failure,particularly those with unclear etiology.Acute management of myasthenic crisis includes ventilatory therapy,removal of the offending trigger and immunomodulatory treat-ments.The latter includes plasma exchange or intravenous immunoglobulin,and high dose corticosteroids therapy.

Anti-musk Myasthenic Crisis in the Puerperium: The Management Dilemma.

Myasthenia gravis (MG) is a chronic neuromuscular junction (NMJ) dysfunction with a wide spectrum of neurological manifestations. MG is as a result of autoantibodies directed against NMJ at the postsynaptic level involving nicotinic or other postsynaptic antigens. The newly identified subtype of MG with antibodies against the muscle-specific receptor tyrosine kinase (Anti-MuSK) shows an unpredictable response to current MG treatment. The initial presentation of this disease entity often poses a diagnostic challenge and a treatment dilemma to the clinician. We present a case of life threatening Anti-MuSK-positive myasthenic crisis occurring during puerperium which required a temporary surgical airway and percutaneous endoscopic gastrostomy tube for feeding. She had dysphonia for 7 years but was not diagnosed. The complications and management dilemma of this case report are highlighted.

Miastenia gravis: un diagnóstico diferencial importante a la hora de evaluar a un paciente con sintomatología ORL / Myasthenia gravis: an important differential diagnosis when assessing a patient with ent symptomatology

La miastenia gravis (MG) es una enfermedad autoinmune que afecta a la unión neuromuscular, y que se caracteriza por la presencia de autoanticuerpos dirigidos contra los receptores de membrana postsinápticos, bloqueando así la transmisión neuromuscular, y logrando de esta forma un descenso en el número de receptores en la placa neuromotora. Se presenta clínicamente como una debilidad muscular focalizada, de algunos grupos musculares, o generalizada. En el contexto ORL las presentaciones más clásicas afectan a la musculatura bulbar, presentándose como disfonía, disfagia, debilidad de la musculatura facial o la combinación de todas ellas. Presentamos 2 casos clínicos de pacientes con manifestaciones totalmente distintas de la misma enfermedad. En el primer caso se presenta a una paciente con compromiso leve de la musculatura bulbar y en el segundo, un paciente con una miastenia generalizada que es internado grave en la UCI por una crisis miasténica. Realizamos una revisión bibliográfica de las últimas pruebas diagnósticas y tratamientos para la MG, y tratamos de definir los signos y síntomas que nos ayudarán como otorrinolaringólogos a un diagnóstico y tratamiento oportuno.

Myasthenia gravis is an autoimmune disease of the neuromuscular junction, characterized by the presence of autoantibodies directed against the postsynaptic membrane receptors, blocking neuromuscular transmission in skeletal striated muscles, leading to a decrease in the number of receptors at the motor neuroplate. Clinically, myasthenia gravis presents as focalized or generalized muscle weakness. For the ENT the most frequent presentation is the bulbar involvement which presents as dysphonia, dysphagia, weakness of facial musculature or a combination of all. We report 2 cases of patients with completely different manifestations of the same disease. The first case is a patient with mild bulbar musculature compromise and the other, is a patient with severe generalized myasthenia who had to be admitted to the ICU for a myasthenic crisis.

The myasthenic patient in crisis: an update of the management in Neurointensive Care Unit / Pacientes miastenicos em crise: uma melhora de conduta na unidade de terapia intensiva

Myasthenia gravis (MG) is an autoimmune disorder affecting neuromuscular transmission leading to generalized or localized muscle weakness due most frequently to the presence of autoantibodies against acetylcholine receptors in the postsynaptic motor end-plate. Myasthenic crisis (MC) is a complication of MG characterized by worsening muscle weakness, resulting in respiratory failure that requires intubation and mechanical ventilation. It also includes postsurgical patients, in whom exacerbation of muscle weakness from MG causes a delay in extubation. MC is a very important, serious, and reversible neurological emergency that affects 20–30% of the myasthenic patients, usually within the first year of illness and maybe the debut form of the disease. Most patients have a predisposing factor that triggers the crisis, generally an infection of the respiratory tract. Immunoglobulins, plasma exchange, and steroids are the cornerstones of immunotherapy. Today with the modern neurocritical care, mortality rate of MC is less than 5%.

Miastenia grave (MG) é um distúbio autoimune que afeta principalmente a transmissão neuromuscular, levando a fraqueza muscular generalizada ou localizada. É devida mais frequentemente à presença de auto-anticorpos anti-receptores de acetilcolina na fenda pós-sináptica da placa motora. A crise miastênica (CM) é uma complicação da MG caracterizada por piora da fraqueza muscular, resultando en falência respiratória, o que requer entubação endotraqueal e ventilação mecânica. Isto ocorre também em pacientes pós-cirúrgicos, em que há piora da fraqueza muscular devido à MG, causando um atraso na extubação. MC é uma emergência neurológica importante, séria e reversível que afeta 20–30% dos pacientes miastênicos, usualmente duranteo primeiro ano de enfermidade, podendo a crise miastênica ser a manifestação inicial da MG. A maioria dos pacientes tem fatores predisponentes que desencadeiam a crise, geralmente uma infecção do trato respiratório. Imunoglobulina, plasmaférese e esteróides são a pedra angular da imunoterapia. Hoje, dentro da terapia neurocrítica, a taxa de mortalidade na CM é menor que 5%.