Treatment of myasthenia gravis. Report on 139 patients

Abstract

In the treatment of myasthenia gravis (MG) considerable progress has recently been achieved. Our experience is based on the observation of 139 patients with an average follow-up of 3 years and 4 months. A treatment plan and results are presented. Indications for thymectomy: all cases of MG in adult life, apart from ocular myasthenia without radiological thymoma and without electrophysiological and pharmacological signs of generalization; before puberty only cases with radiological thymoma and severely incapacitating or life-threatening signs. Median sternotomy is preferable for thymoma, the transcervical approach with a sternal split for non-neoplastic thymus. Mediastinal radiotherapy is indicated after removal of an invasive or adhesive thymoma. Indications for corticosteroids: 1) before thymectomy: respiratory weakness; 2) soon after thymectomy: life-threatening signs; 3) later after thymectomy: incapacitating or life-threatening signs; 4) as an alternative to thymectomy: when surgery cannot be performed or it is not indicated. Oral Prednisone was nearly always preferred: alternate-day high single dose (75 to 115 mg) has given good results in most cases even if in some cases a small dose was required in the "off day"; inversely a lower alternate-day or daily dose was often sufficient. Long-term results: following this schedule for adult patients good results were scored in 67% of thymomas, in 94% of hyperplasias, and in 62% of unthymectomized patients: in prepuberal life the few cases of severe MG have all shown a favorable evolution.