Introduction. - Primary hypoparathyroidism and adhesive capsulitis of the shoulder in the same patient does not seem to have been reported previously. We report two cases in first-degree relatives.

Patients. - Case 1: In 1999, a 41-year-old woman experienced seizures simulating epilepsy. She had been treated 5 years earlier for idiopathic adhesive capsulitis of both shoulders. Computed tomography of the brain showed calcifications in the basal ganglia meeting criteria for Fahr's disease, and incipient bilateral cataract was found. A diagnosis of idiopathic primary hypoparathyroidism was given. After 1 month of calcium and vitamin D supplementation, improvements were noted in the clinical symptoms, laboratory test, and electroencephalogram. Case 2: The 70-year-old father of case 1, who had an unremarkable medical history, had been receiving treatment for about 2 years for adhesive capsulitis of the left shoulder. Routine laboratory tests disclosed idiopathic primary hypoparathyroidism. The outcome was favorable with calcium and vitamin D supplementation.

Conclusion. - Our cases suggest that there may be a common immunological or genetic basis for primary hypoparathyroidism and adhesive capsulitis. Alternatively, adhesive capsulitis may be a manifestation of hypoparathyroidism. Although genetic factors involved in primary hypoparathyroidism have been elucidated, the pathophysiology of the disease remains unclear. Finally, a chance association remains possible.