Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1100 page)

   
Normal range:
12–65 pg/mL.

   Use

   Differential diagnosis of hyperparathyroidism and hypoparathyroidism.

   Very sensitive in detecting PTH suppression by 1,25-dihydroxyvitamin D; therefore, used for monitoring that treatment of chronic renal failure.

   Intraoperative PTH assay to determine removal of abnormally secreting tissue; may replace routine frozen section; can replace traditional four-gland explorations and distinguishes single from multiglandular disease.

   Preoperative and 10–20 minutes postresection assay; this causes 50–75% reduction, indicating successful resection of parathyroid adenoma.

   Interpretation

Increased In

   Primary and secondary hyperparathyroidism

   Pseudohypoparathyroidism

   Hereditary vitamin D dependency types 1 and 2, vitamin D deficiency

   Z-E syndrome

   Familial medullary thyroid carcinoma

   MEN types I, IIa, and IIb