Miastenia ocular juvenil. A propósito de tres casos

espanolCaso clinico: Presentamos 3 casos de miastenia ocular en ninos menores de 5 anos y analizamos su seguimiento. Todos debutaron con ptosis y alteracion de la motilidad ocular extrinseca (MOE). En el estudio diagnostico, un paciente presento anticuerpos contra receptor de acetilcolina negativos y electromiograma patologico; otro, anticuerpos positivos y electromiograma normal; el tercero, positividad de ambas pruebas. Fueron tratados con bromuro de piridostigmina, necesitando dos de ellos tratamiento corticoideo adicional. Discusion: Ptosis variable y alteraciones en la MOE son sugestivos de miastenia ocular, asi como autoinmunidad positiva y electromiograma alterado. El diagnostico precoz es fundamental dado su potencial ambliopizante. EnglishClinical case: We present 3 cases of ocular myasthenia in children under the age of five and we analyse their monitoring. All of them debuted with ptosis and altered extrinsic ocular motility. In the diagnostic study, one patient presented negative antibodies against acetylcholine receptor and pathological electromyogram; another one, positive antibodies and standard electromyogram; the third one, positivity in both tests. Patients were treated with pyridostigmine bromide, two of them needing additional corticoid treatment. Discussion: Variable ptosis and altered extrinsic ocular motility are suggestive of ocular myasthenia, as well as positive autoimmunity and altered electromyogram. Early diagnosis is essential given its tendency to amblyopia.