OBJECTIVES

To describe the clinical profile and outcomes of a series of adult patients diagnosed with ocular myasthenia gravis and to evaluate the potential factors affecting the risk of generalization.

This retrospective cohort study involved a medical chart review of adult patients seen from 2012 to 2019 at the neuro-ophthalmology clinic of a tertiary Philippine hospital with a clinical diagnosis of ocular myasthenia gravis supported by serologic, electrophysiologic, or pharmacologic test results. Outcomes of interest were complete stable remission, pharmacologic remission, minimal manifestations, and generalization. Kaplan-Meier method and log-rank test were used to analyze the probability of generalization.

The study sample consisted of 16 patients. The female to male ratio was 3:1. Mean age at symptom onset was 39 years. All patients received pharmacologic treatment, while two patients underwent thymectomy. No patient had remission as of last follow-up. Three patients had conversion of ocular myasthenia gravis to generalized myasthenia gravis. Mean time from symptom onset to generalization was 10.7 months. The generalization curves of patients who were symptomatic for less than two years and those who were symptomatic for at least two years prior to consult were significantly different (p = 0.049).

In this single-center study, there was female predominance among adult patients diagnosed with ocular myasthenia gravis. The incidence of generalization was 4 per 100 person-years while the 2-year probability of generalization was 30%. Further study is needed in order to determine the factors affecting the risk of generalization.

This study investigated the mechanism by which Jianpi Bushen Yiqi Decoction promotes acetylcholine receptor(AChR) clustering in myasthenia gravis through the Agrin/low-density lipoprotein receptor-related protein 4(LRP4)/muscle-specific receptor tyrosine kinases(MuSK) signaling pathway. A total of 114 female C57BL/6J mice were divided into the normal group, modeling group, and solvent control group. The normal group and the solvent control group were immunized with phosphate-buffered saline(PBS), while the modeling group was established as an experimental autoimmune myasthenia gravis(EAMG) model using the murine-derived AChR-α subunit R97-116 peptide fragment. After successful modeling, the mice were randomly assigned to the model group, the low-, medium-, and high-dose Jianpi Bushen Yiqi Decoction groups, and the prednisone group. After four weeks of continuous treatment, muscle strength was assessed using Lennon scores and grip strength tests. Immunofluorescence staining was conducted on differentiated C2C12 myotubes incubated with a drug-containing serum to observe the number of AChR clusters. The integrity of AChR on myofilaments in mouse gastrocnemius muscles was further assessed by immunofluorescence staining. Hematoxylin-Eosin(HE)staining was applied to examine pathological changes in the gastrocnemius muscles of EAMG mice treated with Jianpi Bushen Yiqi Decoction. Western blot was utilized to detect the expression of key proteins in the Agrin/LRP4/MuSK signaling pathway in both C2C12 myotubes and mouse gastrocnemius muscles. The results demonstrated that compared to the model group, the prednisone group exhibited a significant decrease in the body weights of mice, whereas no significant differences in the body weights of mice were observed among the low-, medium-, and high-dose Jianpi Bushen Yiqi Decoction groups. All treatment groups showed significantly improved grip strength and Lennon scores. Additionally, the formula promoted AChR clustering on myotubes and enhanced AChR integrity in gastrocnemius myofilaments and reduced inflammatory infiltration between muscle tissue and fibrous hyperplasia. Furthermore, Jianpi Bushen Yiqi Decoction upregulated the protein expression of AChRα1, Agrin, and p-MuSK in C2C12 myotubes and increased the protein expression of AChRα1, Agrin, MuSK, p-MuSK, LRP4, and docking protein 7(Dok-7)in gastrocnemius tissue. In conclusion, Jianpi Bushen Yiqi Decoction may promote AChR clustering by targeting key proteins in the Agrin/LRP4/MuSK signaling pathway, thereby improving neuromuscular junction function and enhancing muscle strength.
Animals ; Agrin/genetics* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; Receptors, Cholinergic/genetics* ; Female ; Mice, Inbred C57BL ; Receptor Protein-Tyrosine Kinases/genetics* ; Neuromuscular Junction/metabolism* ; Myasthenia Gravis, Autoimmune, Experimental/physiopathology* ; Humans ; LDL-Receptor Related Proteins

OBJECTIVES

To describe the clinical profile and outcomes of a series of adult patients diagnosed with ocular myasthenia gravis and to evaluate the potential factors affecting the risk of generalization.

This retrospective cohort study involved a medical chart review of adult patients seen from 2012 to 2019 at the neuro-ophthalmology clinic of a tertiary Philippine hospital with a clinical diagnosis of ocular myasthenia gravis supported by serologic, electrophysiologic, or pharmacologic test results. Outcomes of interest were complete stable remission, pharmacologic remission, minimal manifestations, and generalization. Kaplan-Meier method and log-rank test were used to analyze the probability of generalization.

The study sample consisted of 16 patients. The female to male ratio was 3:1. Mean age at symptom onset was 39 years. All patients received pharmacologic treatment, while two patients underwent thymectomy. No patient had remission as of last follow-up. Three patients had conversion of ocular myasthenia gravis to generalized myasthenia gravis. Mean time from symptom onset to generalization was 10.7 months. The generalization curves of patients who were symptomatic for less than two years and those who were symptomatic for at least two years prior to consult were significantly different (p = 0.049).

In this single-center study, there was female predominance among adult patients diagnosed with ocular myasthenia gravis. The incidence of generalization was 4 per 100 person-years while the 2-year probability of generalization was 30%. Further study is needed in order to determine the factors affecting the risk of generalization.

Thymomas are rare tumours which generally account for only 0.2 – 1.5% of mediastinal tumours in adults. Around 40% of patients present with systemic symptoms such as motor weakness due to myasthenia gravis (MG), pure red cell aplasia, and hypogammaglobulinemia. Based on recent guidelines, management of advanced thymoma uses a multimodal approach, which is thymectomy followed by radiotherapy, but not all health care centers have radiotherapy facilities. A 52-year-old woman presented with nasal voice and had difficulty swallowing food. Patient was diagnosed with myasthenia gravis (MG). CT scan with contrast of the thorax showed a heterogenous solid mass in anterior mediastinum. Histopathological examination showed thymoma type B2. Thymectomy followed by seven cycles of platinum-based chemotherapy were done on the patient. Evaluation afterward showed complete remission of thymoma. The patient’s motor weakness improved after the chemotherapy. Post-chemotherapy period was uneventful at six months on follow-up visit. The dosage of acetylcholinesterase inhibitor drug is reduced periodically due to improvement in motor weakness. The case emphasizes how to manage an advanced thymoma with MG with limited therapeutic options, and the importance of multidisciplinary management involving oncologists, surgeons, and neurologists.
Thymoma ; Myasthenia Gravis ; Drug Therapy ; Thymectomy

The incidence rate of Myasthenia Gravis coexisting with other autoimmune diseases is approximately 8.7 – 25%, but it is rarely associated with premature ovarian insufficiency (POI) with only less than 1% of women affected. This is a case of premature ovarian insufficiency in a 29 year old woman diagnosed with Myasthenia Gravis, who presented with lower extremity weakness and experienced two episodes of myasthenic crisis requiring thymectomy. Three years after, she noted oligomenorrhea that quickly progressed to amenorrhea. Extensive immunologic and genetic investigative studies showed no identifiable cause for the POI, except for its close temporal relationship with the occurrence of Myasthenia Gravis. The patient has been responsive to hormone replacement and immunomodulation therapy, and has not developed any further episodes of myasthenic crisis. A review of seven other reported cases describing a similar condition was also included in the discussion.
Myasthenia Gravis

INTRODUCTION

Pure red cell aplasia (PRCA) is defined as anemia in the presence of severe reticulocytopenia and absent or markedly decreased erythroid precursors in the marrow. When associated with another disease entity, it is classified as secondary acquired PRCA. A rare entity, thymolipoma, which constitutes 2% to 9% of thymic tumors has been associated with PRCA in some studies. The prevalence of thymolipoma among patients with myasthenia gravis reaches 43.8%. This paper presents the rare presentation of myasthenia gravis associated with thymolipoma and PRCA.

We present the case of a 64-year-old female who was diagnosed with myasthenia gravis and has been on maintenance pyridostigmine (Mestinon) for 12 years. She presented with symptoms of anemia and became transfusion requiring. Routine chest CT showed a thymic mass which was confirmed to be a thymolipoma during biopsy. Bone marrow studies confirmed the absence of erythroids, hence the diagnosis of secondary acquired PRCA.

There have been case reports associating PRCA with thymolipomas. Thymolipomas, which constitute 2% to 9% of thymic tumors are found among patients with myasthenia gravis, but the majority remains asymptomatic despite increasing tumor size. PRCA with associated thymic mass shows improvement of symptoms with tumor removal and immunosuppression. Oral corticosteroids result in a response rate of 39% while cyclosporine results in 77% response. This can be tapered off once response has been achieved.

This case report emphasizes the importance of early bone marrow studies among patients with myasthenia gravis presenting with sudden onset anemia.

Rheumatoid arthritis (RA) and myasthenia gravis (MG) are two distinct autoimmune diseases. Compared with the general population, the incidence of RA is notably higher among patients with MG. Similarly, the rate of MG in patients diagnosed with RA is also significantly increased. In this report, we presented an elderly female patient with a history usage of long-term glucocorticoid and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), whose RA symptoms remained inadequately controlled. She later exhibited drooping of the right eyelid and double vision, leading to a diagnosis of ocular myasthenia gravis (OMG). Then, we made a literature review and found that the RA patients with co-existing MG were relatively more common in middle-aged and elderly women, and most of them did not have thymoma. Thymoma wasn ' t found in our patient, which was consistent with the cli-nical characteristics of RA complicated with MG reported in previous reports. In addition, there was li-mited treatment experience in patients with both RA and MG. The treatment stratergies for RA or MG included glucocorticoids and immunosuppressants. Among the 18 patients we analyzed, 8 patients expe-rienced relief after csDMARDs, while other 8 patients received biologics or targeted DMARDs, including tumor necrosis factor inhibitors (TNFi) in 5 cases, JAK inhibitors in 2 cases, and B-cell depletion therapy (rituximab) in 2 cases. What called for special attention was that one RA patient was diagnosed with MG after using 23 months of methotrexate and 6 weeks of etanercept (TNFi), with rituximab 1 000 mg for the first time, followed by 500 mg every 6 months, and finally both RA and MG were well controlled. For the patient in this study, MG symptoms improved with increased dosage of prednisone. In order to tapper the dose of glucocorticoid, it was necessary for more potent immunosuppressant for both RA and MG. Given her history of cardiac conditions, JAK inhibitors were not considered, and due to the uncertain efficacy of TNFi, we chose to administer low-dose rituximab (100 mg). Subsequent follow-up revealed stable conditions for both RA and MG, allowing for discontinuance of glucocorticoid after 5 months. It reflected the potential efficacy and cost-effectiveness of low-dose, long-interval rituximab in treating RA patients combined with MG, while it also minimized infection risks. However, the duration for subsequent infusions remained uncertain and required further observation. In conclusion, RA combined with MG is rare. For patients exhibiting poor responses to csDMARDs, low-dose, long-interval rituximab might be a promising treatment option.
Humans ; Arthritis, Rheumatoid/drug therapy* ; Rituximab/administration & dosage* ; Myasthenia Gravis/drug therapy* ; Female ; Antirheumatic Agents/administration & dosage* ; Aged ; Glucocorticoids/therapeutic use*

OBJECTIVES: To investigate the clinical effect of different immunosuppressive treatment regimens in children with ocular myasthenia gravis (OMG). METHODS: A retrospective analysis was conducted on 130 children with OMG who were treated in the Department of Neurology, Jiangxi Children's Hospital, from February 2018 to February 2023. According to the treatment regimen, they were divided into four groups: glucocorticoid (GC) group (n=29), mycophenolate mofetil (MMF) group (GC+MMF; n=33), methotrexate (MTX) group (GC+MTX; n=30), and tacrolimus (FK506) group (GC+FK506; n=38). Treatment outcomes and adverse reactions were compared among the groups. RESULTS: After 3 months of treatment, the FK506 group had significantly lower scores of Myasthenia Gravis Quantitative Scale and Myasthenia Gravis-Specific Activities of Daily Living than the other three groups (P<0.05). After 3 months of treatment, the FK506 group had a significantly lower dose of prednisone than the GC group, and after 6 and 9 months of treatment, the MMF, MTX, and FK506 groups had a significantly lower dose of prednisone than the GC group (P<0.05). After 12 months of treatment, the MMF, MTX, and FK506 groups had a significantly lower incidence rate of GC-related adverse reactions than the GC group (P<0.05). CONCLUSIONS For children with OMG, the addition of various immunosuppressants can reduce the dosage of GC and adverse reactions. Among them, FK506 shows superior efficacy compared to other immunosuppressants in the early treatment of OMG.
Humans ; Child ; Prednisone/adverse effects* ; Tacrolimus/adverse effects* ; Retrospective Studies ; Activities of Daily Living ; Immunosuppressive Agents/adverse effects* ; Myasthenia Gravis/drug therapy* ; Glucocorticoids/therapeutic use* ; Mycophenolic Acid/adverse effects*

Autoantibodies ; Calcium Channels ; Humans ; Myasthenia Gravis ; Receptors, Cholinergic/metabolism*

OBJECTIVE: To compare the clinical efficacy between acupuncture combined with western medication and simple western medication for ocular myasthenia gravis (OMG), and to explore its possible mechanism. METHODS: A total of 60 patients of ocular myasthenia gravis were randomized into an acupuncture combined with western medication group (30 cases, 1 case dropped off) and a western medication group (30 cases, 2 cases dropped off). Oral pyridostigmine bromide tablet and prednisone acetate tablet were given in the western medication group. On the basis of the treatment in the western medication group, Tongdu Tiaoqi acupuncture (acupuncture for unblocking the governor vessel and regulating qi ) was applied at Baihui (GV 20), Fengfu (GV 16), Hegu (LI 4), Zusanli (ST 36), etc. in the acupuncture combined with western medication group, once a day, 6 days a week. The treatment was given 8 weeks in both groups. Before and after treatment, the OMG clinical absolute score was observed, electrophysiological indexes of orbicularis oculi (value of mean jitter, percentage of jitter >55 μs and percentage of blocks) were measured by single-fiber electromyography (SFEMG), serum levels of acetylcholine receptor antibody (AChR-Ab), interferon-gamma (IFN-γ) and interleukin-4 (IL-4) were detected by ELISA method. RESULTS: After treatment, the OMG clinical absolute scores, values of mean jitter, percentages of jitter >55 μs, percentages of blocks and serum levels of AChR-Ab, IFN-γ and IL-4 were decreased compared before treatment in both groups (P<0.05), and those in the acupuncture combined with western medication group were lower than the western medication group (P<0.05). CONCLUSION Acupuncture combined with western medication can effectively improve ptosis, palpebra superior fatigability, eye movement disorder and neuromuscular junction dysfunction in patients with ocular myasthenia gravis, the therapeutic effect is superior to simple western medication. Its mechanism may be related to down-regulating serum levels of AChR-Ab, IFN-γ and IL-4 and promoting the recovery of orbicularis oculi function.
Acupuncture Therapy ; Facial Muscles ; Humans ; Interferon-gamma ; Interleukin-4 ; Myasthenia Gravis/drug therapy*