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PubMedDate not supplied

[Factors which may influence the surgical outcome in myasthenia gravis].

OBJECTIVE: This study intends to assess the factors which may influence the surgical outcome in myasthenia gravis. METHOD: 52 myasthenic patients were operated on in the IIIrd surgical unit, Iaşi, undergoing extended thymectomy through a complete longitudinal sternotomy during a period of 21 years (1980-2001), the surgical outcome being variable. The following factors: age, clinical stage (Osserman classification), the history length and the histopathology of the specimen were analysed in respect with the surgical outcome which varied from complete remission and clinical improvement till no effect and death. Out of 52 patients, 28 were under the age of 30 years and 24 above 30 years of age. 5 patients were operated on in the first clinical stage, 34 in the second clinical stage, 10 in the third stage and 3 in the fourth. 21 patients had had under 1 year history of the disease, 11 patients under 2 years and 20 patients over 2 years. 40 cases presented non-tumoral pathology of the thymus gland and 12 cases presented thymomas. RESULTS: The best surgical results were recorded in patients under 30 years of age, operated in the first and second clinical stage, with a history under 1 year and non-tumoral pathology of the thymus. CONCLUSION: Myasthenia gravis is the only one acquired autoimmune disease in which surgical treatment offers the chance of complete remission if the following criteria are encountered: young patient, short history, initial clinical stage and non-tumoral pathology.

Adolescent↗
PubMed2003

[310 cases of thymectomy for myasthenia gravis].

OBJECTIVE: To evaluate the clinical characteristics and long-term outcome of 310 cases of thymectomy for myasthenia Gravis. METHODS: The data of 310 patients with thymectomy were analyzed retrospectively to study the patient selection, operative techniques, perioperative management and results for myasthenia Gravis. Absolute and relative scores for clinical evaluation were used as the criteria to determine the therapeutic effects of thymectomy. RESULTS: There were no operative death and postoperative complication rates were 8.7% (27/310). The extra anatomic thymic tissue was found in up to 38.7% (120/310) patients and thymus hyperplasia occurred in 92.9% (288/310) cases. 92.6% (287/310) postoperative patients were followed up for 3 or more months; the percentage of patients being remitted, essentially remitted, significantly effective, effective and non-effective were 7.1% (22/310), 11.3% (35/310) 40.0% (124/310), 27.1% (84/310), 7.1% (22/310) respectively. The total long-term effective rate was 85.5% (265/310). The effective rate for type I, IIa, IIb, III, IV was 90.9% (20/22), 97.6% (40/41), 95.3% (162/170), 80.6% (29/36), 77.8% (14/18) respectively. CONCLUSIONS: Generalized typed and properly selected recurrent ocular-typed patients with Myasthenia Gravis undergoing extensive thymectomy would have good long-term outcomes.

Adult↗
PubMed2003

Myasthenia gravis in pediatric and elderly patients.

OBJECTIVE: To determine whether the clinical and pathologic characteristics and prognoses of myasthenia gravis (MG) patients below 15 years differ from those patients over 50 years after thymectomy. METHODS: We reviewed the registry material of 30 pediatric and 32 elderly MG patients after thymectomy, including their age, sex, clinical classification, pathological types, and prognoses. The Chi-square test or Wilcoxon's rank-sum test was used to determine the statistical differences between the children and elderly groups. RESULTS: No significant difference was seen in sex distribution between the two groups. (Chi-square test, P=0.625), but there were differences in clinical classification: more type I was observed in the pediatric group than in the elderly group, but more type II or III was seen in the elderly group (Wilcoxon's rank-sum test, P<0.001). As to pathological types, the pediatric group was also significantly different from the elderly group (Chi-square test, P<0.01). All of the patients (100%) in the pediatric group had thymus hyperplasia, but in the elderly group more than half (56.26%) were found to have thymoma (benign or malignant). The prognoses after thymectomy were better in the pediatric group than in the elderly group (Wilcoxon's rank-sum test, P<0.001). CONCLUSIONS: Because the prognoses are generally better than those of the elderly patients, we should be careful when operating on pediatric patients of ocular type. The elderly patients tend to receive more aggressive treatment because of more severe generalized types often associated with thymoma and poor prognoses. Both pediatric and elderly patients are seldom associated with other autoimmune disease.

Adolescent↗
PubMedDate not supplied

[Advances in the research on immunopathogenesis of myasthenia gravis].

Microscopic structure and immunologic function of the thymus gland are outlined, with an emphasis on its role in the process of T and B lymphocytes maturation. Other types of thymic cells are also described, including epithelial and myoid cells that presumably have a central role in initiation of an autoimmunologic process leading to myasthenic symptoms development. A detailed account is presented of issues concerning pathophysiology of myasthenia, the structure of nicotinic acetylcholine receptor (AchR) at neuromuscular junctions, and mechanisms underlying its destruction by autoantibodies. The role of T and B lymphocytes, of various cytokine types, of autoantibodies to various striated muscle antigens, as well as a possible role of genetic and bacterial factors in the development of myasthenia gravis are discussed. In conclusion it is stressed that since recent research findings go beyond the classic theory of myasthenia, a new consistent theory of the disease immunopathogenesis must be created in the future to place all the newly discovered phenomena in a logical conceptual structure.

Autoantibodies↗
PubMed1992

[Myasthenia gravis and steroid therapy].

In the past 20 years, we experienced 242 myasthenic patients in our hospital. Fifty five cases were administered high doses of adrenocorticosteroid hormone for a long time. Among them, we analysed 39 cases with complete clinical records from admission to the present. We analysed 5 additional cases in whom responses to the therapy somewhat unique in that four cases have not shown any improvement until the drug was reduced to certain dosages, and in the 5th case change of method from alternate-day to every day brought good recovery of the symptoms. As a result, adrenocorticosteroid hormone was effective for 100% of the patients in this series. However, complete remission appeared in the above mentioned 10 patients (26%), after 2-3 years' continuous administration. Prognosis was far better in those who showed shorter durations between the onset of the disease and thymectomy or thymectomy than in those of longer one. In these cases, the maximum daily doses were 60-100 mg in alternate-day administration, and the total amount of prednisolone was 9-15 g in individual cases. Through data of these cases, it is recommended that the maximum dosage is to be continued for as long as 2 to 19 weeks with average 7 weeks.

Adolescent↗
PubMed1991

Thymic enlargement in children.

The presence of an anterior mediastinal mass in an infant or child is a diagnostic and therapeutic challenge. Few papers in the literature specifically address subtypes of thymic tumors in the pediatric population and their treatment. Our purpose was to determine which children are at significant risk of having a malignant thymic tumor. Four children were younger than 18 months old. Of these, two (50%) had respiratory distress from tracheal compression although all four had benign tumors. Of the 14 older children, only two were symptomatic, both of these from myasthenia gravis rather than the size of the mass compressing surrounding structures. Four of the 14 masses (29%) were malignant although none of the four were symptomatic. Children with benign tumors lived significantly longer than those with malignant tumors. The significant incidence of malignancy in thymic tumors when the patient is 18 months or older necessitates surgical exploration with complete removal of the mass. Children younger than 18 months require close follow-up and a trial of corticosteroids. Surgery is necessary if the mass enlarges or becomes symptomatic.

Adolescent↗
PubMed1990

Retrovirus-like particles in human thymomas.

The pathogenesis of thymoma is unclear. In this study retrovirus-like particles in human thymomas were detected by electron microscopy. Forty-two thymomas; 25 without complications and 17 associated with autoimmune disorders such as myasthenia gravis (13), systemic lupus erythematosus (1), polymyositis (1), Sjögren's syndrome (1), and pure red cell anemia (1), were examined. Thymic tissues from 9 infants suffering from congenital heart diseases and 7 hyperplastic thymuses obtained from myasthenic patients served as controls. The retrovirus-like particles were observed in 37.0% of thymomas without complications; 50.0% of thymomas associated with myasthenia gravis and other autoimmune disorders; 62.5% of thymuses associated with myasthenia gravis; and 33.3% of thymuses from infants with heart disease. The envelopes, including the central cores of the retrovirus-like particles, had diameters ranging from 70 to 460 nm, depending on the source of the specimen. The retrovirus-like particles were located in the cytoplasm, vacuoles, vesicles and lumens of the endoplasmic reticula of epithelial and/or plasma cells. Some retrovirus-like particles were seen budding from plasma membranes. These observations suggest that the retrovirus-like particles in thymomas might be an activated form of retrovirus originating in normal thymic tissue.

Heart Defects, Congenital↗
PubMed1988

[Immunohistochemical study of 11 epithelial tumors of the thymus or thymomas with anti-keratin antibodies: KL-1].

Eleven cases of epithelial tumours of the thymus or thymoma and two thymuses without tumour were studied, using immunohistochemistry with anti-keratin antibodies (KL-1) which recognise cyto-keratin with a high molecular weight. In the normal thymus, KL-1 positivity seems to be limited to medullary epithelial elements and in particular Hassal's corpuscles. All the epithelial thymic tumours studied showed a net positivity for KL-1 overall in the tumour cells. This result and the demonstration of more or less well differentiated Hassal's corpuscles in these tumours make one think that these epithelial thymic tumours express some characters in relation with a differentiation of medullary type.

Antibodies, Monoclonal↗
PubMed1989

Clinical and molecular studies in Duchenne muscular dystrophy.

X-linked DMD is a serious condition characterized by progressive muscle wasting and weakness and death ensues in the late teens or early twenties. There is considerable clinical variability even within families and some suggestions of genetic heterogeneity. Though skeletal muscle is primarily involved, other tissues are also affected including cardiac and smooth muscle. Other abnormalities include mental retardation, thymus hyperplasia and possibly certain endocrinological changes. The responsible locus is at Xp21 and the gene product is a very large protein (dystrophin) which is normally localised to muscle cell membranes. It is hypothesised that its absence in DMD may result in instability of the muscle cell membrane with resultant ingress of calcium, an increase in intracellular calcium, and cell death. An understanding of this pathway is important in devising an effective treatment.

Animals↗