[A case of Kennedy-Alter-Sung syndrome associated with external ophthalmoplegia--therapeutic efficacy of fluoxymesterone].

We reported a case with Kennedy-Alter-Sung syndrome (KAS) associated with bilateral external ophthalmoplegia. The patient had movement disturbance of bilateral infra-oblique muscles. The doll's eye phenomenon was not noted. It was suggested that the external ophthalmoplegia was due to the involvement of the oculomotor nucleus that innervated infra-oblique muscle. The serum levels of testosterone and gonadotropin were high, suggesting that the feminization of KAS patients was caused by androgen insensitivity. The feminization of KAS patients is similar to the incomplete form of testicular feminization syndrome except that they do not have feminization of genitals. Therefore, we proposed that abnormalities of androgen receptors might play a role in the pathogenesis of KAS. Fluoxymesterone therapy significantly improved the muscle weakness of the extremities of the patient, even though the therapeutic efficacy was shown temporarily. The therapeutic efficacy of fluoxymesterone for muscle weakness supports our hypothesis.