[Thymectomy in juvenile myasthenia gravis]

Juvenile myasthenia gravis (JMG) is an infrequent autoimmune disease, the symptoms and therapeutic handling of which do not differ from those of the adult forms. Chronic treatment with corticoids very often causes side effects in childhood, which is why patients are being submitted to thymectomies at younger ages with better results. AIMS. To analyse the clinical and evolutionary profile of JMG treated by thymectomy in our centre.

We report the case of four girls aged between 5 and 13 who were diagnosed as suffering from generalised myasthenia gravis (MG) with bulbar affectation. One of them started with a myasthenic crisis. The four of them were submitted to Tensilon s test, an electrophysiological study, determination of AChR, thoracic CT, and study of autoimmunity and thyroid functioning. After surgery the thymus was analysed histologically.

They all gave positive in Tensilon s test and were seropositive for AChR. They were treated with anticholinesterases, up to the maximum tolerated dose, and corticoids, without complete remission being accomplished and so they were submitted to a thymectomy in the first year of evolution. In three cases surgical approach was transsternal and in the other by means of a videothoracoscope. All the thymuses showed lymphoid hyperplasia. After a variable follow up the girls are at present asymptomatic, although none of them has been able to completely give up the pharmacological treatment.

Thymectomy is one of the mainstays of treatment for JMG. The ever more frequent use of videothoracoscopic techniques achieves results that are similar to those obtained by conventional surgery but with fewer post operative and aesthetic problems