Rapid increase in bone mineral density in a child with osteoporosis and autoimmune hypoparathyroidism treated with PTH 1-34.

We describe a 16-year-old girl with autoimmune polyglandular syndrome type 1 including hypoparathyroidism, who had osteoporosis that improved rapidly with parathyroid hormone replacement therapy. Patients with hypoparathyroidism usually have high bone mass. Our patient developed vertebral compression fractures at age 10, shortly after hypoparathyroidism was diagnosed. She continued to have low lumbar bone mass until age 16, when a dual energy x-ray absorptiometry (DEXA) revealed a Z score of - 2.2 SD. Several factors including decreased physical activity, total body magnesium depletion, and intermittent ketoconazole and short-term prednisone treatment, may have contributed to the development and progression of osteoporosis. Therapy with synthetic human parathyroid hormone (PTH) 1-34 rapidly normalized lumbar bone mass, as assessed by DEXA.