Parathyroid hormone analysis

A blood sample was sent for parathyroid hormone (PTH) analysis. In the meantime, the patient and her family were questioned further.

There was no history of bone pain, recent fractures, or kidney stones. The patient did not use diuretics (e.g., thiazides, which can raise calcium). A breast exam, mammography, and chest xray did not suggest malignancy. Stool analysis for occult blood (which might be a clue to a GI malignancy) was negative.

The parathyroid hormone tests yielded the following results: 

                             Patient         Reference
PTH, intact molecule (P)    56 pg/ml            9 - 51
Calcium, total (S)        13.6 mg/dl        8.4 - 10.1
Calcium, ionized (S)       6.9 mg/dl         4.4 - 5.5

(S = serum, P = plasma)

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