First, these labs very clearly indicate primary hyperparathyroidism, since the calcium and PTH are both far outside normal range.

We don’t need anything else to make the diagnosis. A low calcium diet is not going to change this diagnosis. Your calcium and PTH levels may both fluctuate to some extent, since that happens with primary hyperparathyroidism, but the diagnosis will not change.

CT scans (and all parathyroid scans for that matter) are often wrong when it comes to primary hyperparathyroidism. Parathyroid tumors can be very small and as a result may not show up on any scans. Imaging studies are not needed to make the diagnosis. And you do not need a “positive” scan in order to have parathyroid surgery. If your labs indicate primary hyperparathyroidism, then you are a candidate for surgery whether we see a tumor on scan or not.

Regarding diet: it is unlikely that avoiding all dietary calcium will change your serum calcium level all that much. As mentioned above, the levels can fluctuate. So you may see a slightly lower calcium in a few months, but that doesn’t mean that the disease is improving, or has changed at all. The calcium can rise or fall somewhat with each blood draw, but the disease is still there. With primary hyperparathyroidism, the calcium is high because the parathyroid tumor is overactive, not because you are getting too much calcium in diet.

It is actually very hard to take in so much calcium through diet that you would raise your serum calcium level. You can raise your calcium level by taking Vitamin D supplements, which is why I recommend not taking Vitamin D supplements when the calcium is high. Having a normal amount of dietary calcium is not likely to chance the calcium, though.

The only cure for primary hyperparathyroidism is surgery. Dietary changes will not affect the overall course of the disease.