Secondary Hyperparathyroidism is quite common. I see a new case nearly every week. Secondary Hyperparathyroidism happens when the parathyroid glands are doing their job.
If you do not have enough calcium in your diet, or if you take meds for GERD (heartburn), or if your vitamin D level is low, or if you take Calcium Carbonate instead of Calcium Citrate, or if you have Colitis or Irritable Bowel Syndrome, you may not be absorbing enough calcium.
Your serum calcium level MUST be maintained to keep your heart working. Therefore the parathyroid glands increase PTH in order to release calcium from the bones. Over months and years huge amounts of calcium can be stolen from your bones. This can cause Low Bone Mineral Density and Osteoporosis.
A normal serum calcium level and a high PTH usually indicate Secondary Hyperparathyroidism. To detect this you must test for PTH. DXA usually shows low BMD. Often the Vertebral Fracture Assessment (VFA) shows weakened bones in the form of Vertebral Compression Fractures.
Treatment is straightforward. We need to bring vitamin D levels to above 40ng/ml. This often requires megadose vitamin D3. We need to supply 1200 to 1500 mg calcium daily in diet and supplements. We usually switch to Calcium Citrate.
We retest PTH (and usually 25-hydroxy vitamin D) 3 months later. Almost always the Secondary Hyperparathyroidism is resolved. Often fixing calcium and vitamin D intake is all we need. Sometimes we need to add Osteoporosis Medications for persistent Osteoporosis.
Jay Ginther, MD
2009, Revised May 2011