RESUMEN
BACKGROUND: Non-motor symptoms in myasthenia gravis (MG) are rarely confirmed. Although there are some small cohort studies, a large-systemic survey has not yet been performed. METHODS: We investigated the incidence and clinical characteristics of patients with MG who had taste disorders and alopecia using data of 1710 patients with MG enrolled in the Japan MG Registry 2021. RESULTS: Among them, 104 (6.1%) out of 1692 patients and 138 (8.2%) out of 1688 patients had histories of taste disorders and alopecia, respectively. Among the patients with MG, taste disorders were significantly more common in women, those with severe symptoms, refractory MG, or thymoma-associated MG, and were less common in those with ocular MG. The taste disorders often occurred after the onset of MG and often responded to MG treatments. Alopecia was more common in MG patients with a history of bulbar palsy and thymoma, and it often occurred before the onset of MG and sometimes responded to MG treatments. Multivariate logistic regression analysis revealed taste disturbance was associated with worst quantitative MG score and thymoma-associated MG; and alopecia was associated with thymoma-associated MG. CONCLUSION: Clinicians should be aware of the non-motor symptoms in MG, especially in patients with severe myasthenic symptoms and thymoma-associated MG.
Asunto(s)
Alopecia , Miastenia Gravis , Trastornos del Gusto , Humanos , Miastenia Gravis/epidemiología , Miastenia Gravis/complicaciones , Miastenia Gravis/diagnóstico , Alopecia/epidemiología , Alopecia/diagnóstico , Femenino , Masculino , Trastornos del Gusto/epidemiología , Trastornos del Gusto/etiología , Persona de Mediana Edad , Adulto , Anciano , Japón/epidemiología , Sistema de Registros , Timoma/complicaciones , Timoma/epidemiología , IncidenciaRESUMEN
Myasthenia gravis (MG) is an autoantibody-mediated disease of the neuromuscular junction. Semaphorin 4A (Sema4A) is involved in the activation of T cells in various inflammatory disorders. In this study, we aimed to investigate whether Sema4A is involved in the pathogenesis of MG. We measured serum Sema4A concentrations in 30 treatment-naïve MG patients with acetylcholine receptor (AChR) antibodies, 7 with muscle-specific tyrosine kinase (MuSK) antibodies and 21 normal controls. As a result, serum Sema4A levels were significantly higher in patients with AChR antibody-positive MG and MuSK antibody-positive MG than in controls (p ≤ 0.0001 for both MG groups). Serum Sema4A levels were correlated with AChR antibody levels (Spearman's ρ = 0.39, p = 0.03) and MG Foundation of America clinical classification classes (Spearman's ρ = 0.38, p = 0.04) in patients with AChR antibody-positive MG. In conclusion, high serum Sema4A levels may reflect T-cell activation, and this molecule could be a potential marker of disease activity in MG.
Asunto(s)
Miastenia Gravis , Semaforinas , Humanos , Miastenia Gravis/diagnóstico , AutoanticuerposRESUMEN
This study included 51 patients with muscle-specific kinase antibody-positive myasthenia gravis (MuSK-MG) from a Japanese multicenter survey to examine clinical features and outcomes. Median onset age was 37 years and female predominance was observed. All patients developed generalized symptoms and almost all (50/51) patients had bulbar symptoms. About half of the patients met the criteria for refractory MG. The refractory group had a lower age of onset, higher severity scores, and higher maximum daily doses of oral prednisolone compared to the nonrefractory group. The outcomes for MuSK-MG patients in Japan are not favorable, indicating the need for more aggressive treatment.
Asunto(s)
Miastenia Gravis , Humanos , Femenino , Adulto , Masculino , Japón , Miastenia Gravis/tratamiento farmacológico , Miastenia Gravis/diagnóstico , Prednisolona/uso terapéutico , Músculos , Autoanticuerpos/uso terapéuticoRESUMEN
This study measured the serum levels of of 15 cytokines in 15 patients with anti-muscle-specific kinase antibody-positive MG (MuSK-MG) using a multiplex suspension array system. Fifteen patients with non-inflammatory neurological diseases served as controls. Compared with controls, patients with MuSK-MG showed higher levels of Th1- (IFN-γ), Th2- (IL-25, IL-31, and IL-33), Th17- (IL-22), Treg-related cytokines (IL-10), and soluble CD40 ligand (sCD40L). Higher serum Th2-related cytokines (IL-25 and IL-31) levels were correlated with less MG Foundation of America (MGFA) class. These suggest that Th2-related cytokines have protective effects, whereas sCD40L and others may facilitate the disease.
Asunto(s)
Miastenia Gravis , Humanos , Citocinas , Células Th17RESUMEN
INTRODUCTION/AIMS: Myasthenia gravis (MG) is an autoimmune disease affecting the neuromuscular junction (NMJ) of skeletal muscle. Complement activation is one of the mechanisms by which anti-acetylcholine receptor (anti-AChR) autoantibodies reduce synaptic transmission at the NMJ. In this study, we aimed to examine the activation of the complement pathways, including the classical pathway, as potential contributors to the pathogenesis of MG with anti-AChR antibodies. METHODS: In this single-center, observational study of 45 patients with anti-AChR-antibody-positive generalized MG, serum concentrations of major components of the complement pathways, including C1q, C5, C5a, soluble C5b-9 (sC5b-9), Ba, and complement factor H, were measured using an enzyme-linked immunosorbent assay. A total of 25 patients with a non-inflammatory neurological disorder served as controls. In addition, the relationships of complement activation with clinical characteristics were examined. RESULTS: The patients with MG exhibited lower serum levels of C5 (p = .0001) and higher serum levels of sC5b-9 (p = .004) compared with the control group. At about 6 months (range, 172-209 days) after the start of immunotherapy, serum levels of Ba were significantly higher than baseline levels (p = .002) and were associated with improvement in MG clinical scores. DISCUSSION: Herein, we provide evidence for the activation of the classical complement pathway and its association with disease activity in anti-AChR-antibody-positive generalized MG.
Asunto(s)
Vía Clásica del Complemento , Miastenia Gravis , Humanos , Receptores Colinérgicos , Autoanticuerpos , Unión Neuromuscular/metabolismo , Complejo de Ataque a Membrana del Sistema ComplementoRESUMEN
The purpose of this study was to evaluate the safety and efficacy of BL 23 (Shenshu) acupuncture on serum cytokine levels. Sixteen healthy adults were randomized into the BL 23 acupuncture group or pseudo-acupuncture group and changes of serum cytokines were analyzed. The changes in IL-13, TNF-α, and GM-CSF levels were different between the BL 23 acupuncture group and pseudo-acupuncture group (P < 0.05). No adverse events associated with acupuncture were observed. In conclusion, BL 23 acupuncture can suppress immune responses via decreases in TNF-α and suppression of increases in IL-13 and GM-CSF. This study elucidated some of the mechanisms of the acupuncture effect.
Asunto(s)
Terapia por Acupuntura , Citocinas , Humanos , Adulto , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Factor de Necrosis Tumoral alfa , Interleucina-13RESUMEN
The efficacy of intravenous high-dose methylprednisolone (IVMP) in ocular myasthenia gravis (MG) has not been fully established. This study aimed to elucidate the effects of early intervention with IVMP for achieving the therapeutic targets (minimal manifestations [MM] or MM or better status with prednisolone ≤ 5 mg/day [MM5mg]) in ocular MG. In this observational study, we included a total of 1710 consecutive patients with MG enrolled in the Japan MG Registry in 2021. Of these, 204 patients with ocular MG who received immunotherapy were analyzed. The clinical course and time to first achieve MM or MM5mg after starting immunotherapy were compared between the early IVMP group (treated with IVMP within 3 months of treatment initiation) and the non-early IVMP group. Despite having greater clinical severity before immunotherapy and lower oral prednisolone doses throughout the course, the early IVMP group (n = 55) showed a higher rate of achievement of MM (P = 0.0040, log-rank test; hazard ratio 1.58, 95% confidence interval [CI] 1.13-2.20, P < 0.0001) and MM5mg (P = 0.0005, log-rank test; hazard ratio 1.78, 95% CI 1.27-2.51, P < 0.0001) compared with the non-early IVMP group (n = 149). In conclusion, an early intervention with IVMP is likely to increase the probability of achieving a better long-term outcome and reducing the total dose of corticosteroids in ocular MG.
Asunto(s)
Metilprednisolona , Miastenia Gravis , Humanos , Metilprednisolona/uso terapéutico , Resultado del Tratamiento , Administración Intravenosa , Miastenia Gravis/tratamiento farmacológico , InmunoterapiaRESUMEN
OBJECTIVES: Minimal symptom expression (MSE), defined as myasthenia gravis (MG) activities of daily living profile (MGADL) score 0 or 1, has been recently used as an indicator of treatment goal in MG. However, no study has determined when MSE is achieved. The current study aimed to investigate the timing and incidence of MSE achievement in generalized MG patients. METHODS: Eighty-five patients with acetylcholine receptor antibody-positive generalized MG were included. They were followed-up maximum 3 years after starting immunotherapy, and we reviewed the MGADL score, prednisolone dose, and achievement of MSE and minimal manifestations (MM) or better status. RESULTS: MSE was achieved in 37.6, 45.2, 55.8, 60.3, and 57.1% of the patients at 3, 6, 12, 24, and 36 months after treatment, respectively. Most patients who achieved MSE showed MM or better status at any phase. In addition, more than 2 years after the starting treatment, about 80% of patients who achieved MSE showed MM or better status with an oral prednisolone dose of 5 mg/day or less (MM-5 mg). Noteworthy, during the early stage of treatment, the proportion of patients who achieved MSE was higher than that who achieved MM-5 mg. CONCLUSION: From the early phases of immunotherapy, MSE is a good marker of therapeutic goal in patients with generalized MG.
Asunto(s)
Actividades Cotidianas , Miastenia Gravis , Humanos , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamiento farmacológico , Receptores Colinérgicos , Prednisolona/uso terapéutico , AutoanticuerposRESUMEN
BACKGROUND/AIM: Low risk asymptomatic bone metastasis (LRABM) without gross osteolytic changes tends to be out of indication for radiotherapy. The aim of this study was to evaluate the time between the end of palliative radiotherapy of bone metastasis (BM) until the start of new pain, in patients with painful BM. PATIENTS AND METHODS: Patients with BM were prospectively assessed for location and strength of pain every month for one year after radiotherapy. The correlation of pain relapse at irradiated site, and pain onset outside the irradiated site was evaluated with sex, age, primary tumor, pathology of tumor, visceral metastases, baseline scores for Eastern Cooperative Oncology Group performance status (PS), and baseline verbal rating scale (VRS). RESULTS: A hundred and thirty-two patients were included (79 males and 53 females). Median age was 66 years. Primary sites were lung (n=60), breast (n=17), colon (n=12), prostate (n=11), and others (n=33) (one patient had two primary sites). Median follow-up was 185 days. Pain relief was observed in 92 patients (86.0%). Out of them, pain progression was observed in 69.6%. Median time to pain progression was 75.5 days. Pain onset outside the irradiated site was observed in 57 patients (43.2%). Median time to pain onset was 109 days. Out of the 57 patients, 13 (22.8%) had LRABM which existed before the start of radiotherapy. There were 54 patients with LRABM in this study and because many patients had more than one LRABM, the total LRABM sites were 123. Out of them, pain onset was observed within one year after irradiation in 44 (36%) lesions. Median time to pain onset was 67 days, which was the shortest of the three: irradiated site, out of the irradiated site, and LRABM site. Risk factors for high probability of pain onset within one year in LRABM lesions were female sex (showing a trend in univariate analysis), and pelvic, skull and spine metastasis (significant in multivariate analysis). CONCLUSION: Time to pain onsets in LRABM are relatively short, especially in female patients with pelvic, skull and spine metastasis. In these patients, prophylactic radiotherapy could be an option to consider.
Asunto(s)
Neoplasias Óseas , Dolor , Masculino , Humanos , Femenino , Anciano , Estudios Prospectivos , Dolor/etiología , Dolor/radioterapia , Cuidados Paliativos , Neoplasias Óseas/secundario , Enfermedad Crónica , RecurrenciaRESUMEN
BACKGROUND: Early fast-acting treatment (EFT) is the aggressive use of fast-acting therapies such as plasmapheresis, intravenous immunoglobulin and/or intravenous high-dose methylprednisolone (IVMP) from the early phases of treatment. EFT is reportedly beneficial for early achievement of minimal manifestations (MM) or better status with ≤5 mg/day prednisolone (MM5mg), a practical therapeutic target for myasthenia gravis (MG). OBJECTIVE: The current study aimed to clarify which specific EFT regimen is efficacious and the patient characteristics that confer sensitivity to EFT. METHODS: We recruited a total of 1710 consecutive patients with MG who enrolled in the Japan MG Registry for this large-cohort study. Among them, 1066 with generalised MG who had received immunotherapy were analysed. Prognostic background factors were matched in a 1:1 ratio using propensity score matching analysis between patients treated with EFT (n=350) and those treated without EFT (n=350). The clinical course and time to first achieve MM5mg after starting immunotherapy was analysed in relation to treatment combinations and patient characteristics. RESULTS: Kaplan-Meier analyses showed that EFT had a significant effect on the achievement of MM5mg (p<0.0001, log-rank test; HR 1.82, p<0.0001). Notably, EFT was efficacious for any type of MG, and the inclusion of IVMP resulted in earlier and more frequent achievement of MM5mg (p=0.0352, log-rank test; HR 1.46, p=0.0380). In addition, early administration of calcineurin inhibitors also promoted MM5mg achievement. CONCLUSION: Early cycles of intervention with EFT and early use of calcineurin inhibitors provides long-term benefits in terms of achieving therapeutic targets for generalised MG, regardless of clinical subtype.
Asunto(s)
Inhibidores de la Calcineurina , Miastenia Gravis , Humanos , Inhibidores de la Calcineurina/uso terapéutico , Estudios de Cohortes , Miastenia Gravis/tratamiento farmacológico , Metilprednisolona/uso terapéutico , InmunoterapiaRESUMEN
This study examined the role of Tfh and Treg associated molecules also known as checkpoint molecules, their ligands, and IL-21 in myasthenia gravis (MG) pathogenesis. Serum levels of sPD-1, sPD-L1, sICOS, sICOSLG, sCTLA4, and IL-21 were measured in 39 patients with acetylcholine receptor (AChR) antibody-positive generalized MG and 27 controls. sPD-1 and IL-21 levels were higher in MG patients than in controls. Additionally, sPD-1 levels correlated positively with the levels of IL-21, sICOSLG, sCTLA4, and AChR antibody titers. sICOS are correlated with MGADL and AChR antibody titers. These Tfh associated molecules could be used as biomarkers of MG disease activity.
Asunto(s)
Miastenia Gravis , Linfocitos T Colaboradores-Inductores , Humanos , Receptores Colinérgicos , Autoanticuerpos , Membrana CelularRESUMEN
OBJECTIVE: Myasthenia gravis (MG) is an antibody-mediated inflammatory disease affecting post-synaptic membranes of neuromuscular junctions, and objective biomarkers of MG disease activity are lacking. Pentraxin 3 (PTX3) is an acute-phase inflammatory glycoprotein in the same family as C-reactive protein that is associated with disease activity in several autoimmune disorders. Thus, we investigated whether circulating PTX3 is a useful biomarker of MG activity. METHODS: Serum PTX3 was measured in 40 patients with MG who were positive for anti-acetylcholine receptor antibody, and in 30 healthy and disease controls, using a commercial enzyme-linked immunosorbent assay kit. In patients with MG, the correlation of serum PTX3 levels with disease severity scales at serum sampling, including MG Foundation of America (MGFA) classification, MG activity of daily living (MG-ADL) score, and quantitative MG (QMG) score, were investigated. RESULTS: Although there was no significant difference in serum PTX3 between the MG and control groups (mean, 3346 pg/mL in MG group vs. 2870 pg/mL in control group, P = 0.56), serum PTX3 moderately correlated with all disease severity scores (MGFA classification: Spearman's ρ = 0.53, P = 0.0004; MG-ADL score: Spearman's ρ = 0.45, P = 0.004; QMG score: Spearman's ρ = 0.50, P = 0.004). CONCLUSION: Our results suggest that circulating PTX3 may reflect the extent of neuromuscular junction damage and might be involved in the pathogenesis of MG.
Asunto(s)
Proteína C-Reactiva , Miastenia Gravis , Componente Amiloide P Sérico , Biomarcadores , Proteína C-Reactiva/metabolismo , Humanos , Componente Amiloide P Sérico/metabolismo , Índice de Severidad de la EnfermedadRESUMEN
Immune-mediated necrotizing myopathy (IMNM) is a pathologically defined diagnosis of idiopathic inflammatory myopathies. Adequate studies on cytokines of IMNM is lacking. We measured serum levels of 27 cytokines/chemokines in 22 IMNM patients, 10 sporadic inclusion body myositis (IBM) patients, and 23 other neurological disorders (ONDs) patients. In IMNM patients, the correlations between clinical features and cytokine/chemokine levels, and changes in cytokine/chemokine levels after immunosuppressive therapy were examined. Compared with ONDs patients, IMNM patients had significantly increased serum levels of several cytokines. In particular, IP-10 and MIP-1α levels were prominently increased, decreased after immunosuppressive-therapy, and correlated with serum creatine kinase levels. IP-10 and MIP-1α could play important roles in the IMNM pathogenesis.
Asunto(s)
Enfermedades Autoinmunes , Miositis , Enfermedades Autoinmunes/diagnóstico , Quimiocina CCL3 , Quimiocina CXCL10 , Citocinas , Humanos , Músculo Esquelético/patologíaRESUMEN
Immunoadsorption apheresis (IA) or intravenous immunoglobulin (IVIg) is used to treat exacerbation of myasthenia gravis (MG). This study aimed to compare the efficacy and safety between IA and IVIg for MG patients with anti-acetylcholine receptor (AChR) antibodies. We retrospectively studied 19 AChR antibody-positive generalized MG patients who underwent IA (n = 9) or IVIg treatment (n = 10). We reviewed the MG activities of daily living profile (MG-ADL) scores at baseline, 1 and 3 months after the treatment. Adverse events during the treatment period were also reviewed. The MG-ADL scores showed significantly greater improvement from the baseline in the IA group than in the IVIg group (1 month: -7 vs -3, P = .035; 3 months -9 vs -2.5, P = .016). An adverse event that led to the discontinuation of the treatment was observed in only one patient in the IVIg group (anaphylactic reaction). Our data suggest that the IA treatment is safe and more efficacious than the IVIg treatment for aggravation of anti-AChR-positive MG. Larger prospective studies are required to confirm the finding.
Asunto(s)
Autoanticuerpos/sangre , Eliminación de Componentes Sanguíneos/métodos , Inmunoglobulinas Intravenosas/uso terapéutico , Miastenia Gravis/terapia , Autoanticuerpos/inmunología , Eliminación de Componentes Sanguíneos/efectos adversos , Femenino , Humanos , Inmunoglobulinas Intravenosas/efectos adversos , Masculino , Persona de Mediana Edad , Miastenia Gravis/inmunología , Receptores Colinérgicos/inmunología , Estudios RetrospectivosRESUMEN
BACKGROUND AND OBJECTIVES: To investigate intrathymic B lymphopoiesis in patients with myasthenia gravis (MG) and explore thymus pathology associated with clinical impact. METHODS: Thymic lymphocytes from 15 young patients without MG, 22 adult patients without MG, 14 patients with MG without thymoma, and 11 patients with MG with thymoma were subjected to flow cytometry analysis of T follicular helper (Tfh), naive B, memory B, plasmablasts, CD19+B220high thymic B cells, B-cell activating factor receptor, and C-X-C chemokine receptor 5 (CXCR5). Peripheral blood mononuclear cells of 16 healthy subjects and 21 untreated patients with MG were also analyzed. Immunologic values were compared, and correlations between relevant values and clinical parameters were evaluated. RESULTS: The frequencies of circulating and intrathymic plasmablasts were significantly higher in patients with MG than controls. On the other hand, the frequency of CD19+B220high thymic B cells was not increased in MG thymus. We observed a significant increase in CXCR5 expression on plasmablasts in MG thymus and an increased frequency of intrathymic plasmablasts that was correlated with preoperative disease activity. The frequency of intrathymic Tfh cells was significantly lower in patients who received immunosuppressive (IS) therapy than those without IS therapy. However, there was no significant difference in the frequency of intrathymic plasmablasts irrespective of IS therapy. DISCUSSION: Our findings confirmed a correlation between increased frequency of intrathymic plasmablasts and disease activity before thymectomy. We postulate that activated intrathymic plasmablasts endow pathogenic capacity in MG.
Asunto(s)
Linfocitos B , Leucocitos Mononucleares , Linfopoyesis , Miastenia Gravis , Células Madre , Linfocitos T , Timoma , Neoplasias del Timo , Adolescente , Adulto , Anciano , Linfocitos B/inmunología , Niño , Preescolar , Femenino , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad , Miastenia Gravis/sangre , Miastenia Gravis/inmunología , Miastenia Gravis/fisiopatología , Células Madre/inmunología , Linfocitos T/inmunología , Timectomía , Timoma/sangre , Timoma/inmunología , Timoma/fisiopatología , Neoplasias del Timo/sangre , Neoplasias del Timo/inmunología , Neoplasias del Timo/fisiopatología , Adulto JovenRESUMEN
Myasthenia gravis (MG), a neuromuscular junction disorder, is caused by pathogenic autoantibodies. Interleukin-6 (IL-6) plays important roles in T helper 17 (Th17), T follicular helper (Tfh), and B cell activations as well as in antibody production. This study aimed to evaluate the clinical significance of serum IL-6 level as a biomarker of disease activity in patients with anti-acetylcholine receptor (AChR) antibody-positive MG. In the present study, serum IL-6 levels were measured in 93 treatment-naïve patients with anti-AChR antibody-positive MG and compared with those in 101 controls. Moreover, correlations between serum IL-6 levels and clinical characteristics were analyzed. Serum IL-6 levels were significantly higher in patients with anti-AChR antibody-positive MG than in controls (median [interquartile range], 2.5 [1.5-8.3] pg/mL vs. 1.5 [1.5-3.2] pg/mL, P < 0.001). The serum levels were correlated with the MG Foundation of America clinical classification (Spearman's ρ = 0.27; P < 0.01) and decreased following immunosuppressive treatment in parallel with disease activity (P = 0.01). In conclusion, IL-6 is involved in the pathogenesis of anti-AChR antibody-positive MG and could be a therapeutic target in MG.
Asunto(s)
Autoanticuerpos/sangre , Progresión de la Enfermedad , Interleucina-6/sangre , Miastenia Gravis/sangre , Miastenia Gravis/diagnóstico , Anciano , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Myasthenia gravis (MG) is an autoimmune disease with autoantibodies against the mainly nicotinic acetylcholine receptor (AChR). High mobility group box1 (HMGB1) acts as a danger signal and drives the pathogenesis of autoimmune-mediated diseases. However, the role of HMGB1 in the pathogenesis of MG is not fully understood. Therefore, in this study, we analyzed serum levels of HMGB1 and immunohistochemical HMGB1 staining of muscle tissues in the passive transfer MG model to investigate the role of HMGB1 in MG. As a result, serum HMGB1 levels tended to be higher and the quantitative score of muscle pathology showed greater HMGB1 deposition (P = 0.02) along with sparser AChR staining and more severe inflammation in the passive transfer MG rats (n = 6) than those in control rats (n = 6). These findings indicate that HMGB1 is an important mediator and biomarker for inflammation in the pathogenesis of MG and can be a therapeutic target in MG.
Asunto(s)
Proteína HMGB1/metabolismo , Músculo Esquelético/metabolismo , Miastenia Gravis Autoinmune Experimental/metabolismo , Animales , Femenino , Proteína HMGB1/sangre , Miastenia Gravis Autoinmune Experimental/sangre , RatasRESUMEN
INTRODUCTION: In this study we aimed to investigate the dispersion of mean consecutive difference (MCD) of concentric needle jitter studies of patients with myasthenia gravis (MG) and its effect on diagnostic sensitivity for MG. METHODS: One hundred fifty-three patients, including 76 patients with MG and 77 controls with possible MG who later received another diagnosis, underwent stimulated concentric needle jitter studies of the frontalis muscle. MCD mean, standard deviation (SD), and coefficient of variation (CV) were calculated. Diagnostic sensitivity and specificity were determined using receiver operating characteristic (ROC) analyses. RESULTS: MG patients showed a significantly greater MCD mean (MG: control, 26.3 µs; 13.5 µs [median]; P < .0001), MCD SD (MG: control, 12.8 µs; 5.1 µs [median]; P < .0001), and MCD CV (MG: control, 46.1; 37.5 [median]; P < .001) than those without MG. An ROC curve of SD showed a large area under the curve (0.88), and a cut-off value of 7.2 µs, which was calculated by maximum Youden index, exhibited high diagnostic sensitivity (86%) for MG. Combined MCD mean, outliers, and SD criteria showed higher sensitivity (88%) than conventional criteria alone (82%), at the expense of lower specificity. Five MG patients with normal MCD mean and abnormal MCD SD had only ocular symptoms. DISCUSSION: The dispersion of MCD as measured by MCD SD greater than 7.2 µs is significantly increased in patients with MG and may be a useful measure of abnormal jitter in the diagnosis of MG, especially for identifying patients with mild disease.
Asunto(s)
Contracción Muscular/fisiología , Músculo Esquelético/fisiopatología , Miastenia Gravis/diagnóstico , Conducción Nerviosa/fisiología , Potenciales de Acción/fisiología , Adulto , Anciano , Estimulación Eléctrica , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/fisiopatología , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: This study aimed to investigate the timing of meeting the criteria for a status of "minimal manifestation (MM) or better" and the factors that influenced whether "MM or better status" or "MM or better status with an oral prednisolone (PSL) dose of 5 mg/day or less (5-mg MM)" was met in patients with acetylcholine receptor (AChR) antibody-positive generalized myasthenia gravis (MG). METHODS: We performed a retrospective study in 93 patients with AChR antibody-positive generalized MG who were followed for 3 years after the start of immunotherapy. We reviewed clinical data, such as MG-related symptoms, the MG activities of daily living profile (MGADL) score, immunotherapy including the dose of PSL, and achievement of the status of MM or better at baseline and 3, 6, 12, 24, and 36 months after treatment. RESULTS: An MM or better status was achieved in 60% of the patients 3 months and in 90% of the patients 2 years after initiating immunotherapy. At 2 years, 60% of the patients had achieved the treatment goal, which was an "5-mg MM". More frequent plasmapheresis and higher dose of PSL within 3 months after immunotherapy initiation were associated with difficulty in achieving the 5-mg MM status at 2 years. CONCLUSION: Approximately 60% of the MG patients achieved the treatment goal within 2 years after treatment. PSL dose and the cumulative number of plasmapheresis procedures at 3 months after immunotherapy initiation may help identify treatment-resistant patients with MG.
Asunto(s)
Actividades Cotidianas , Miastenia Gravis , Autoanticuerpos , Humanos , Miastenia Gravis/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVE: To investigate the association between changes in anti-acetylcholine receptor antibody (AChR Ab) levels induced by immunosuppressive treatment and myasthenia gravis (MG) prognosis at 1-year post-treatment in patients with MG. METHODS: We included 53 consecutive AChR Ab-positive patients with MG whose AChR Ab levels were remeasured within 100 days of initiating immunosuppressive treatment (median remeasuring time post-treatment: 71 (55-84) days). The AChR Ab level reduction rate (RR-AChRAb, %/day) adjusted for the time between treatment initiation, and AChR Ab level remeasurement was calculated as follows: (pretreatment-post-treatment AChR Ab level)/pretreatment AChR Ab level/days between therapy initiation and AChR Ab level remeasurement ×100. Participants were divided into two groups based on the cut-off value of RR-AChR Ab, determined using receiver operating characteristic analyses for achieving minimal manifestation (MM) or better status at 1-year postimmunosuppressive treatment. The Myasthenia Gravis Foundation of America postintervention status and MG activity of daily living (MG-ADL) score at 1-year post-treatment were compared between the two groups. RESULTS: The RR-AChRAb cut-off value was 0.64%/day. The high RR-AChRAb group had a higher ratio of MM or better status (90% vs 65%, p=0.03) and lower MG-ADL score (median; 1 vs 2, p=0.04) than the low RR-AChRAb group. Kaplan-Meier analyses showed the early MM achievement in the high RR-AChRAb group (p=0.002, log-rank test). CONCLUSIONS: High RR-AChRAb is associated with a favourable outcome at 1-year post-treatment. AChR Ab remeasurement within 100 days of therapy may be useful for predicting AChR Ab-positive MG outcomes at 1-year post-treatment.