Plasmapheresis as preparatory method for thymectomy in myasthenia gravis

Abstract

SUMMARY -To study the effects of plasmapheresis in preparation for thymectomy, two groups of 40 patients were selected from a sample of 286 patients with myasthenia gravis examined by the first author Group 1 included patients (15 male and 25 female; age range 8-64 yrs) who underwent thymectomy without previous plasmapheresis, whereas patients in group 2 (17 male and 23 female; age range 11-61 yrs) were thymectomized after plasmapheresis. We required patients to have a minimum follow-up period of 12 months to be included in the study. A clinical evaluation protocol composed of 76 items was developed for the study. We found significant improvement in respiratory function and muscular strength in patients thymetomized after plasmapheresis. Furthermore, the combined treatment reduced cost and length of hospital stay. Therefore, we conclude that plasmapheresis should be considered as a coadjuvant to thymectomy in the treatment of myasthenia gravis.KEY WORDS: myasthenia gravis, thymectomy, plasmapheresis. Plasmaferese como método preparatório de timectomia em miastenia graveRESUMO -No intuito de estudar as repercussões de um curso de plasmaferese como método preparatório para a timectomia, tomamos duas amostras de 40 pacientes selecionados de um universo de 286 casos de miastenia gravis, em que a investigação clínica, eletrofisiológica, laboratorial, o seguimento e o protocolo foram completamente realizados. Consideramos como grupo 1 aquele em que a timectomia foi realizada sem preparação pre-operatória e grupo 2 aquele em que a plasmaferese foi executada como coadjuvante a timectomia. O grupo 1 era composto de 15 pacientes do sexo masculino e 25 do feminino; a idade variou de 8 a 64 anos com mediana de 30 anos. No segundo grupo, 17 eram masculinos e 23 femininos; a idade variou de 11 a 61 anos com mediana de 33 anos. Foi preenchida ficha de avaliação clínica sequencial de 76 itens e traçamos um curso de plasmaferese de 5 sessões seguido da timectomia, mantendo a mesma técnica operatória, realizada pela mesma equipe cirúrgica, tentando assim minimizar as distorções na análise e manuseio destes pacientes. Obtivemos melhora clínica, da insuficiência respiratória, da força muscular e reduzimos também o custo da internação quando comparada aos pacientes em que a cirurgia foi realizada sem a plasmaferese e em alguns casos em que realizamos preparação com corticosteróides. Acreditamos que a plasmaferese deva ser considerada como método coadjuvante no tratamento cirúrgico desta grave afecção. PALAVRAS-CHAVE: miastenia gravis, timectomia, plasmaferese.Myasthenia gravis (MG) is a disease of the neuromuscular junction characterized by weakness and abnormal fatigue in the skeletal muscles. It was first described by Thomas Willis in 1672.However, a more precise clinical account of this disorder was offered by Campbell and Bramwell in 1900 4 . In 1901, Oppenheim hypothesized that MG was a disease of the neuromuscular junction by analogy with symptoms of curare poisoning 21 . Several clinical aspects suggest that the basic defect ...

Plasmapheresis in the treatment of myasthenia gravis: retrospective study of 26 patients

“…In case 6 PE was performed four days previous to thymectomy for preparing the patient to surgery, as suggested by others 17,21,22 .The patient had difficulty in the maintenance of motor strength while lowering prednisone. As expected postoperative result was uneventful.…”

“…A multicenter study from Taiwan showed that 34.9% of PE was indicated for MG patient 16 . A restricted number of national publications about PE and MG was encountered [17][18][19][20] . Seggia et al 17 from Rio de Janeiro analyzed costs and benefits of PE in the preparation of patients for thymectomy.…”

“…A restricted number of national publications about PE and MG was encountered [17][18][19][20] . Seggia et al 17 from Rio de Janeiro analyzed costs and benefits of PE in the preparation of patients for thymectomy. ing limb, axial muscle or both and lesser involvement of oropharyngeal muscles) in eight cases; IIIb (deficit predominantly oropharyngeal and/or respiratory plus limb and/or axial muscles lesser involved) in 11 cases; IVb (severe weakness predominantly affecting oropharyngeal and/or respiratory muscles, may also have lesser or equal deficit of limb, axial muscles or both) in two and class V (intubated, with or without mechanical ventilation) in five cases.…”

“…In a group of 144 sessions of PE, Wendell Neto et al 19 encountered 10.4 % of paresthesias, 2 % of hypotension and 10,4 % of allergic reactions. Seggia et al 17 also presented a list of PE side effects in their patients, all easily managed.…”

Thymectomy in Myasthenia Gravis

“…This will help in the postoperative period as well as in reducing preoperatively given corticosteroid levels [44]. Seggia et al [45] showed that plasmapheresis significantly improves respiratory functions and muscle strength in patients with myasthenia treated with thymectomy and significantly reduces hospitalization times.…”