ABSTRACT
Pseudohypoparathyroidism is a rare disease that is characterized by target cell resistance to the effects of parathyroid hormone and this disease is classified into various types depending on the phenotypic and biochemical findings. The patients with pseudohypoparathyroidism present with the clinical and biochemical features of hypoparathyroidism, but they have an increased serum level of parathyroid hormone. We experienced a case of pseudohypoparathyroidism in a 24 years old woman who had Graves' disease at that time. She had hypocalcemia, hyperphosphatemia, an elevated serum parathyroid hormone level and a normal urinary basal cyclic AMP(adenosine monophosphate) level. She also had a normal phenotypic appearance. Therefore, she was classified as suffering with pseudohypoparathyroidism type II. The clinical and laboratory abnormalities were improved by calcium supplementation in addition to vitamin D. To the best of our knowledge, this is the first case of pseudohypoparathyroidism combined with Graves' disease in Korea.