Why is my calcium too high?
Ken: This 78 year old presented for evaluation of hypercalcemia. She was incidentally found to have a serum calcium of 10.9 mg/dl. At that time her PTH was 75, phosphate was 2.8 and 25-OH vitamin D was 17 ng/dl. Patient was on HCTZ which was discontinued. 6 weeks later a repeat serum calcium was 11.1 …