[Case report of sister with Duane's syndrome and PGA, or myasthenia gravis].

We report a case of polyglandular autoimmune syndrome (PGA) complicated by Duane's syndrome. The patient was 44-year-old female with marked limitation of abduction in the left eye, lethargy, nonhomogeneous facial pigmentation, goiter, and oligomenorrhea. A diagnosis of chronic thyroiditis was first made to explain the patient's symptoms. Laboratory examinations were performed. Plasma ACTH level was high and plasma cortisol was low, and there was no response to the ACTH stimulation test. The presence of primary adrenocortical deficiency was confirmed. Moreover, primary gonadal failure was also present, and the diagnosis of PGA type II was made. The patient's elder sister had myasthenia gravis which is a condition known to occur with PGA type II. Therefore, the sister was also suspected to have PGA type II, as the syndrome can occur in family members. However, since she had been receiving large doses of steroids for her myasthenia gravis, laboratory findings were inconclusive. Duane's syndrome, which is characterized by congenital oculomotor disturbance, was also seen in the sister. It is still unknown whether the familial occurrence of Duane's syndrome has a genetic basis. There have been reports of congenital disorders occurring in combination with autoimmune diseases. Further investigation into the relationship between congenital anomalies and autoimmune diseases is necessary.