Hi, thanks for writing in.

First, let’s look at your calcium levels. A calcium of 10.2 mg/dl is on the high end for your age. When you are in your 30s, sometimes you can have normal calcium levels in the low 10s. As you get older, your levels will tend to drop into the 9s (mg/dl). After about age 40, most adults should have calcium levels in the mid to high 9s. Typically we see the calcium level drop as you get older. In your case it is rising, which is more concerning for primary hyperparathyroidism. Your calcium of 9.0 in 2021 is actually a little low, which can be from low Vitamin D levels. But your current levels would not be caused by Vitamin D.

Vitamin D deficiency leads to low blood calcium levels, since the main role for Vitamin D is helping your intestines absorb calcium. If your calcium level was currently 9.0, with a low Vitamin D, then I would say that Vitamin D deficiency was the main concern. It’s a different story when the calcium is on the high end with a low Vitamin D. This picture is more consistent with primary hyperparathyroidism, since this causes low Vitamin D. A high calcium plus low Vitamin D often indicates primary hyperparathyroidism.

Your PTH level helps also. At 52 pg/ml, it is technically in “normal” range. But PTH can only be interpreted in relation to the calcium level. If the calcium level is normal, then we want to see a PTH in normal range. If the calcium is high, then we expect the PTH to drop into the low range. Your calcium right now is borderline, so the picture is not entirely clear.

Overall with labs like yours, at your age, I would be concerned about primary hyperparathyroidism, though I would not be prepared to make a final diagnosis. I would want to see more calcium and PTH levels, as well as prior calcium levels. Often with primary hyperparathyroidism the calcium and PTH levels will fluctuate, so if we check it a few more times we may be able to make a definitive diagnosis.