SEARCH · PubMed Health

Results for “MYASTHENIA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

PubMed1984

Myasthenia gravis and HLA antigens in American blacks and other races.

The association of HLA B8 and DR3 with generalised adult onset myasthenia gravis (GMG) in European Caucasoids is now well established. Studies of the HLA association with myasthenia gravis (MG) in other races might help to determine the location of a critical disease locus. Some previous studies in Japanese, Thais, Asian Indians and Filipinos have been reported. In this study HLA A, B, C and DR typing on 28 American blacks with either GMG or ocular myasthenia gravis (OMG) is reported. A significant increase in both HLA A1 and B8 was detected but there was an increase in DR5 rather than DR3. A review of the HLA antigen frequencies in other races and in D-penicillamine (D-Pen) induced MG suggests that prior claims implicating immune response genes marked by DR3 require review. It seems unlikely that any particular HLA allele is involved directly. Other possibly relevant combinations of alleles or supratypes are suggested. These may provide the basis for future studies of the immunogenetic basis for MG.

Asian People↗

PubMed1996

Soluble complement receptor 1 (sCR1) protects against experimental autoimmune myasthenia gravis.

The loss of muscle function seen in myasthenia gravis and in the animal model of the disease, experimental autoimmune myasthenia gravis (EAMG) is in part due to the activation of complement by anti-acetylcholine receptor (AChR) antibodies at the motor end-plate. In this study we describe the effects of a soluble recombinant form of human complement receptor 1 (sCR1) on the development of clinical disease and receptor loss in EAMG induced passively by administration of anti-AChR antibodies. Daily intraperitoneal injection of sCR1 significantly reduced the weight loss and severity of clinical symptoms seen and allowed treated animals to recover normal muscle function. These data suggest that sCR1 could provide a useful additional therapeutic agent in myasthenia.

Animals↗

PubMed1999

Paraneoplastic pemphigus associated with Castleman tumor, myasthenia gravis and bronchiolitis obliterans.

BACKGROUND: Cases of paraneoplastic pemphigus (PNP) have been reported associated with various lymphoproliferative malignancies and benign Castleman tumors, with the most severe course and fatal outcome seen in patients with bronchiolitis obliterans. OBJECTIVE: The aim was to establish immunologic associations by coexistence of Castleman tumor, myasthenia gravis, and bronchiolitis obliterans and to evaluate the treatment modalities. METHODS: Clinical studies included computed tomography of the mediastinum, computed tomography and magnetic resonance imaging of the abdominal cavity, and quantitative electromyography. Direct and indirect immunofluorescence on various substrates, immunoblot analysis, immunoprecipitation, and specific enzyme-linked immunosorbent assay using recombinant desmogleins (Dsg) were performed as immunologic assays. RESULTS: Direct and indirect immunofluorescence including rat bladder showed intercellular antibodies. Immunoblotting disclosed antibodies to envoplakin (210 kd protein) and periplakin (190 kd protein); in addition, immunoprecipitation detected antibodies to desmoplakin I (250 kd protein). Antibodies to Dsg3 (pemphigus vulgaris antigen) were detected by specific enzyme-linked immunosorbent assay. Myasthenia gravis was controlled by drugs; however, mucocutaneous changes were not fully responsive to corticosteroids and cyclophosphamide pulses, cyclosporine, and intravenous immunoglobulins. The surgical removal of Castleman tumor did not change the course of the disease. The fatal outcome was the result of bronchiolitis obliterans that occurred after the surgery and was only transitionally controlled by plasmapheresis. CONCLUSION: This is the first case of paraneoplastic pemphigus associated with Castleman tumor, myasthenia gravis, and bronchiolitis obliterans. Despite a benign character of the tumor the patient died, as do all patients with bronchiolitis obliterans. Massive plasmapheresis has only a transient effect. We confirmed the presence of antibodies to Dsg 3, in addition to the set of specific paraneoplastic pemphigus antibodies against various proteins of plakin family.

Adult↗

PubMed1984

Drugs that may exacerbate myasthenia gravis.

Myasthenia gravis is an uncommon disease. The emergency physician should be cautious when prescribing medications to myasthenics for problems not related to myasthenia gravis. We have discussed some of those agents (Figure 3) that are recognized to cause exacerbation of MG or that may have the potential to exacerbate MG. We recommend that management of any medical or surgical problem of the myasthenic be done in consultation with a managing neurologist, and that either early follow-up or admission is necessary when these agents are used in the patient with myasthenia gravis.

Anti-Bacterial Agents↗

PubMed1983

Acetylcholine receptors and myasthenia gravis.

Recent years have seen considerable progress in understanding the nature of the molecular events involved in neuromuscular transmission. The acetylcholine receptor (AChR) has been purified to homogeneity and acetylcholine-induced ion transport has been reconstituted by incorporation of pure AChR into artificial membranes. Immunization against purified AChR induces a condition, clinically and physiologically similar to the human disease myasthenia gravis, which is due to circulating anti-AChR antibodies. This model, experimental autoimmune myasthenia gravis, is proving useful for investigating the role of genetic factors in determining the immune response to AChRs and for testing various experimental approaches to specific treatment. Myasthenia gravis is an autoimmune disease in which there is loss of acetylcholine receptors at the neuromuscular junction. Anti-AChR antibodies can be detected in the majority of patients and they cause loss of AChR by a variety of mechanisms. Anti-AChR antibody is heterogeneous and not restricted in idiotype. The role of the thymus in MG is still uncertain, but recent experiments implicate the presence of a cell type in MG thymus which may be involved in autosensitization to AChR.

Adolescent↗

PubMed2003

Anticholinergic agents for the treatment of "death rattle" in patients with myasthenia gravis.

Difficulty clearing upper airway secretions (death rattle) is a frequent problem at the end of life. Treatment often includes the use of anticholinergic drugs. Myasthenia gravis is a disease characterized by muscle weakness and fatigue caused by an immune-mediated deficiency of acetylcholine receptors at the neuromuscular junction, and it is treated with anticholinesterase agents. We report the case of a patient dying of myasthenia gravis who had problems with the "death rattle" and who presented a dilemma as to whether the use of anticholinergics would be helpful or would cause deterioration of her myasthenia. This is accompanied by a review of the relevant literature.

Aged↗

PubMed1992

T cells with specificity for idiotypic determinants on human monoclonal autoantibodies in myasthenia gravis.

The activation of T cells from 46 patients with myasthenia gravis and 28 healthy individuals by two human monoclonal autoantibodies was studied. B-cell clones were produced by transformation of peripheral lymphocytes from a patient using Epstein-Barr virus and subsequent cloning. Two myasthenia-specific autoantibodies, one anti-receptor-antibody and one antiidiotypic antibody, both carrying separate recurrent idiotopes, were used in this study. Single activated T cells were identified by their secretion of IL2 and IFN gamma using a cell enzyme-linked-immunosorbent technique. The idiotypic antibody activated T cells in patients but not in most of the controls at concentrations of 1 pg/ml and 10 pg/ml. High concentrations of antibody resulted in T-cell activation in both groups. A similar dose-response pattern was recorded using the antiidiotypic antibody. Incubation with the idiotypic antibody resulted in T-cell stimulation, measured as numbers of IFN gamma-secreting cells that exceeded the mean +2 SD of controls, in 78% of patients and in 7% of the healthy individuals (p less than 0.001). The antiidiotypic antibody activated T cells in 50% of patients and in 4% of the healthy individuals (p less than 0.001). T-cell activation measured as numbers of IL2-secreting cells showed a difference between patients and controls which was as significant as for IFN gamma secretion. The results demonstrate the presence of T cells with specificity for disease-specific determinants on idiotypic and antiidiotypic antibodies in myasthenia gravis.

Adult↗

PubMed1997

[Acute respiratory insufficiency revealing myasthenia gravis: apropos of 3 cases].

BACKGROUND: Myasthenia gravis is usually revealed by a ptosis or a diplopia. A respiratory muscle weakness often occurs during the course but an acute respiratory failure as initial feature is unusual. CASE REPORTS: Three girls, aged 8, 10 and 14 years, were hospitalised in an intensive care unit, along a 15 year-period, for an acute respiratory distress. The first two children suffered from skeletal and bulbar muscle weakness. The third, admitted with the diagnosis of unexplained pneumonia, was complaining of skeletal and bulbar muscle weakness for the last 18 months. Myasthenia gravis was confirmed with electromyography, and detection of the acetylcholine-receptors antibodies in all three cases. CONCLUSION: Any unexplained acute respiratory distress must lead to search for skeletal and bulbar muscle weakness, specially after muscular exercise or at the end of day, manifestations which characterize myasthenia gravis.

Acute Disease↗

PubMed2001

Therapeutic options in ocular myasthenia gravis.

The term ocular myasthenia gravis refers to the disease clinically restricted to extrinsic ocular muscles. It can be disabling as ptosis, and to a greater extent diplopia, both interfere with daily activities. Although ocular disturbances are the most frequent initial complaints in myasthenic patients, symptoms usually progress to generalized disease and only 15% of patients complain of purely ocular weakness for the entire course of their illness. Secondary generalization occurs with the highest frequency in the first 2 years from the onset. Both the severity of symptoms and the risk of generalization should be taken into account when devising a therapeutic plan for these patients. Anticholinesterases are of limited efficacy and a considerable proportion of patients require additional therapy. Corticosteroid therapy, generally prednisone on an alternate-day schedule, is very effective, but a reason for concern is represented by the frequent need for long-term administration with increased risk of severe complications. In patients unresponsive to prednisone or requiring too high dosages, immunosuppressive drugs like azathioprine should be used with the same criteria applied in generalized myasthenia. As corticosteroids and immunosuppressants reduce the chance of generalization, their use is justified in patients with recent-onset disabling disease. In long-standing cases with low risk of generalization, treatment is aimed at the relief of symptoms and pharmacological therapy should be reduced to the minimum effective dosage. The indication for thymectomy in ocular myasthenia remains highly controversial and should be reserved for disabled patients in the early stages of the disease.

Adrenal Cortex Hormones↗

PubMed1999

Thymectomy for myasthenia gravis: a 27-year experience.

OBJECTIVE: Thymectomy is considered an effective therapeutic option for patients with myasthenia gravis (MG). We reviewed our 27-year experience with surgical treatment of MG with respect to long-term results and factors affecting outcome. METHODS: Between 1970 and 1997, we performed 232 thymectomies for MG. Fifteen patients were lost to follow-up; the remaining 217 form the object of our study. Sixty-two patients (28.4%) had thymoma. Myasthenia was graded according to a modified Osserman classification: 51 patients (23.5%) were in class I, 81(37.3%) in class IIA, 52 (24%) in class IIB, 26 (12%) in class III and seven (3.2%) in class IV. Mean duration of symptoms before the operation was 12+/-10 months. Fifty-eight thymectomies for thymoma were performed through a median sternotomy and four through a clamshell incision. Forty-six thymectomies for non-thymomatous MG were performed through a standard cervicotomy, 101 procedures through a partial upper sternal-splitting incision and eight through a complete median sternotomy. RESULTS: Operative mortality was 0.92% (two patients). After a mean follow-up of 119 months, 71% of all patients improved their clinical status (25% without medications and asymptomatic; 46% with a reduction of medications and/or clinically improved); 39 (18%) have a stable disease with no clinical modifications; 12 (5%) presented a deterioration of their clinical status with worse symptoms, required more medications, or both. Thirteen patients (6%) died because of MG (mean survival 34.3+/-3.6 months). The presence of a thymoma negatively influenced the prognosis. Younger patients showed a more favorable outcome as well as patients with a shorter duration of symptoms before the operation; patients with lower classes of myasthenia showed a higher rate of remission. CONCLUSIONS: Thymectomy is effective in the management of patients with MG at all stages with low morbidity. Patients with thymoma present a less favorable outcome.

Adult↗

PubMed1999

Preoperative preparation and anesthetic management of patients with myasthenia gravis.

Patients with myasthenia gravis have specific clinical problems that must be addressed by the anesthesiologist when surgery is contemplated. Optimal perioperative management of myasthenia gravis patients undergoing thymectomy requires careful preoperative assessment and preparation. This assessment and preparation includes evaluation for concomitant autoimmune, respiratory, and cardiac disorders as well as optimization of medical management for myasthenia. There are important intraoperative concerns to be addressed including appropriate monitoring, premedication, and other agents used during surgery including muscle relaxants and anesthetic agents. Postoperatively, attention must be directed specifically to pain relief, ventilatory management, and the appropriate titration of reversal agents and anticholinesterase inhibitors. Optimal management of all these factors maximizes the chance for successful and uncomplicated hospitalization.

Anesthesia, General↗

PubMed2001

Analysis of thymectomy for myasthenia gravis in older patients: a 20-year single institution experience.

BACKGROUND: Thymectomy has become recognized as an integral element in the care of the patient with myasthenia gravis. Although the number of elderly patients with myasthenia is substantial, little data exist demonstrating the efficacy and morbidity of thymectomy in this population. STUDY DESIGN: We retrospectively analyzed 126 cervicomediastinal thymectomies performed at a single university hospital from 1980 to 1998. Patients 55 years or older were compared with those less than 55. Efficacy was measured by determining the change in Osserman score, the rate of remission during followup, and the reduction in medication requirements after thymectomy. RESULTS: Older patients (n = 28) had similar Osserman scores (p = 0.8) and similar rates of complete and partial remission as the younger group (n = 98) at a mean +/- SEM followup of 58 +/- 5 months. The two groups did not differ in the number (p = 0.4) and doses of medications used to control myasthenic symptoms after operation. Older age was associated with an increased length of hospitalization (13.8 +/- 3.2 days versus 9.7 +/- 0.6 days, p = 0.05) and a higher incidence of reintubation, and longer ventilatory support (2.6 +/- 1.3 days versus 0.1 +/- 0.1 days, p = 0.001). CONCLUSIONS: Increased age does not alter the outcomes of thymectomy for myasthenia gravis. Older patients can expect to have similar responses and require a similar number of postoperative medications as younger patients, but with a higher short-term morbidity.

Adolescent↗

PubMed2004

[Video-assisted thoracoscopic thymectomy for the treatment of myasthenia gravis].

OBJECTIVE: Traditionally, thymectomy for myasthenia gravis has been performed using either a transcervical approach or a median sternotomy. However, excision of the thymic tissue by video-assisted thoracoscopic surgery is less aggressive and recovery is faster. The aim of this study was to evaluate the usefulness and outcomes of video-assisted thoracoscopic thymectomy. PATIENTS AND METHODS: Over the past 10 years, we have performed 25 video-assisted thoracoscopic thymectomies on patients with myasthenia gravis at our unit. This study included 16 women and 9 men, with a mean age of 48.1 years (range, 14-74 years). Right-side (22 cases) or left-side (3 cases) thoracoscopic surgery was performed, with a mean intervention time of 110 minutes (range, 60-193 minutes). RESULTS: No patient required assisted ventilation for more than 4 hours and the maximum stay in intensive care was less than 24 hours. Complications from surgery included 3 cases of contralateral pneumothorax, 1 pleural effusion, and 2 intraoperative hemorrhages from the thymic vein, all of which were resolved by video-assisted thoracoscopy. Likewise, 3 cases required conversion (due to hemorrhaging in 2 patients and technical difficulties in 1) and 2 required a second thoracoscopic intervention. No deaths occurred and clinical outcome was excellent in 11 cases (medical treatment no longer required), good in 10 (reduced medical treatment), and poor in 4 (no changes). CONCLUSIONS: Video-assisted thoracoscopic thymectomy is effective in the treatment of myasthenia gravis and improves patient recovery. In addition, the excellent surgical view allows the thymectomy to be performed with absolute safety.

Adolescent↗

PubMed1998

Myasthenia gravis presenting with dysphagia and postoperative ventilatory failure.

We report a case of myasthenia gravis presenting to the department of otolaryngology with acute dysphagia on two separate occasions over a one-year period. Diagnosis of myasthenia gravis was made when the patient developed ventilatory failure after his second general anaesthetic for rigid oesophagoscopy. Our patient required emergency transfer to the intensive therapy unit for ventilation. He improved after treatment with corticosteroids, anticholinesterase and immunosuppressive medications. Our case was unusual in that cricopharyngeal spasm causing dysphagia and significant aspiration was demonstrated by a barium swallow and this was completely resolved after treatment of the myasthenia gravis.

Acute Disease↗

PubMed2006

Myasthenia gravis mimicking unilateral vocal fold paralysis at presentation.

OBJECTIVES: To demonstrate the importance of detailed clinical analysis in the differential diagnosis of unilateral vocal fold paralysis, and to provide an update on current knowledge and treatment of myasthenia gravis. CASE REPORT: A female patient presented with left unilateral vocal fold immobility. Diagnostic investigation revealed a 10 mm thyroid adenoma, but no other abnormality likely to cause unilateral vocal fold paralysis. Follow-up flexible endoscopy at three months showed laryngeal remobilisation with persistent left vocal fold bowing and vertical asymmetry of the vocal folds on phonation. Over the following months, voice quality varied between normal and breathy, with the breathy periods lasting from three days to one month. Laryngeal electromyography (EMG) showed a slight bilateral paradoxical activation of both posterior crico-arytenoid muscles on phonation. Magnetic resonance imaging of the brain and brainstem was normal. A diagnostic test for myasthenia gravis with intravenous edrophonium bromide (Tensilon) lead to an immediate improvement in voice quality. The patient was subsequently treated with pyridostigmine bromide, with complete resolution of dysphonia. CONCLUSIONS: Myasthenia gravis affecting the larynx may mimic unilateral vocal fold paresis or paralysis. A personal or family history of auto-immune disease, fluctuating symptoms, motor deficits in cranial nerve territories, and normal or subnormal laryngeal EMG results should lead the physician to reconsider a diagnosis of idiopathic unilateral vocal fold paralysis and to perform specific testing.

Adult↗

PubMed1999

Pseudo-myasthenia gravis and thymic hyperplasia in Graves' disease.

BACKGROUND: Diagnostic confusion between thyroid disease and myasthenia gravis (MG) can arise because the two may have similar clinical features, and also because of the more frequent coexistence of these autoimmune disorders in the same individual. In MG, autoantibodies directed against the acetylcholine receptor result in muscle weakness. Thymic pathology is well recognized in MG, with thymic hyperplasia frequent in early onset MG and thymoma more common in later onset MG. In Graves' disease, autoantibodies against thyroid antigens result in hyperthyroidism. A seldom-recognized feature of Grave's disease is the occurrence of an enlarged thymus (thymic hyperplasia) on chest CT, or of thymic lymphoid hyperplasia pathologically. CASE STUDY: This report describes a case in which the discovery of a mediastinal mass during imaging of the thyroid, and the presence of myasthenic-like symptoms, in a patient with Graves' disease prompted investigations into whether the patient also had MG. RESULTS: Despite symptoms which strongly suggested MG, subsequent investigations did not confirm the diagnosis, and treatment of Grave's lead to a resolution of the symptoms and regression of the thymic enlargement seen on CT. CONCLUSIONS: The case study highlighted clinical similarities between Grave's disease and myasthenia gravis which might cause diagnostic confusion, and also the investigations which are useful in order to differentiate the two diseases. In addition to common clinical features, the autoimmune diseases Grave's disease and myasthenia gravis may both produce radiological thymic enlargement.

Adult↗

PubMed2002

Immunobiochemical characteristics of IgG antibodies in myasthenia.

The abzyme activity of mAb35 and pQ1-209 was compared with that of normal rabbit IgG and serum IgG from patients with various forms of myasthenia. It was found that mAb35 and pQ1-209 and IgG from patients with myasthenia possess catalytic activity. IgG from myasthenia patients with thymomas possess creatine phosphokinase activity, which 2-fold surpassed the control.

Animals↗

PubMed1999

Myasthenia gravis and polymyositis as manifestations of chronic graft-versus-host-disease.

Myasthenia gravis and polymyositis are each a rare manifestation of immune dysregulation in chronic graft-versus-host disease (cGVHD). We report a 4-year-old boy with idiopathic acquired aplastic anemia who developed myasthenia gravis 22 months and polymyositis 69 months after an allogeneic BMT (5/6 matched, MLC-nonreactive). The occurrence of both syndromes in one patient is unique. Autoimmune dysfunction may be associated with the development of cGVHD as demonstrated by the high incidence of prior aplastic anemia in BMT patients presenting with myasthenia gravis and polymyositis. Recognition of these neurologic manifestations is important in the diagnosis and treatment of cGVHD.

Anemia, Aplastic↗