A 72-year-old woman presents to your office complaining of generalized bone pain and weakness. On further questioning, she reports that she has increased thirst, polyuria, heart burns, constipation, tingling and numbness in her fingers and pruritus. A bone densitometry study reveals a significant loss of cortical bone. You order laboratory studies, which reveal increased calcium levels, increased PTH levels, increased alkaline phosphatase, and decreased phosphate levels. What is the most common cause of this patient’ disorder?
