Extrapyramidal symptoms and advanced calcification of the basal ganglia in a patient with autosomal dominant hypocalcemia.

Most cases of hypoparathyroidism with decreased parathyroid hormone (PTH) secretion, excluding secondary hypoparathyroidism, are considered to be idiopathic. We herein report a relatively rare case of hypoparathyroidism with extrapyramidal symptoms, including brachybasia and a frozen gait, caused by advanced basal ganglia calcification in a 64-year-old man with hypoparathyroidism. A DNA (deoxyribonucleic acid) analysis of blood samples obtained from the patient and his eldest daughter revealed autosomal dominant hypocalcemia (ADH) with mutations in the calcium-sensing receptor (CaSR) gene. In cases of chronic hypoparathyroidism, calcification of the basal ganglia is observed if the patient is not treated for a long period. However, extrapyramidal symptoms as a complication of hypoparathyroidism are relatively rare.