Intra‐operative parathyroid hormone kinetics and influencing factors with high baseline PTH: a prospective study. (1st April 2013)

• Record Type: Journal Article
• Authors: Singh, Dependra N.; Gupta, Sushil K.; Chand, Gyan; Mishra, Anjali; Agarwal, Gaurav; Verma, Ashok Kumar; Mishra, Saroj Kanta; Shukla, Manoj; Agarwal, Amit
• Is Part Of: Clinical endocrinology. Volume 78:Number 6(2013:Jun.)
• Page Start: 935
• Page End: 941
• Publication Date: 2013-04-01
• Subjects: Endocrinology -- Periodicals; 616.4005
• DOI: 10.1111/cen.12067
• Languages: English
• ISSNs: 0300-0664

Abstract

<abstract abstract-type="main" id="cen12067-abs-0001"> <title>Summary</title> <sec id="cen12067-sec-0001" sec-type="section"> <title>Background and objective</title> <p>Intra‐operative parathyroid hormone (IOPTH) kinetics and therefore the efficacy of IOPTH utilization as a predictor of cure are likely to be affected by baseline IOPTH levels, vitamin D deficiency and parathyroid weight.</p> </sec> <sec id="cen12067-sec-0002" sec-type="section"> <title>Patients and methods</title> <p>Consecutive subjects with primary hyperparathyroidism (PHPT, <italic> n</italic> = 51) undergoing parathyroidectomy with IOPTH monitoring were studied prospectively during the period October 2009–November 2011. Samples were collected pre‐incision, pre‐excision and post‐excision (5, 10, 15 min). Iterative analysis of IOPTH kinetics and half‐life calculation was carried out in subgroups. Nonparametric testing was used for group statistics.</p> </sec> <sec id="cen12067-sec-0003" sec-type="section"> <title>Results</title> <p>Hypovitaminosis D (25(OH)D<sub>3</sub> < 50 n<sc>m</sc>) was present in 39 (76%), serum PTH > 1000 ng/l in 23 (45%), and giant parathyroid adenoma (weight > 3000 mg) in 23 (45%). The percentage drop at 10 min was significantly higher in large adenomas (weight > 3000 mg). Miami and 5 min criteria showed the highest negative predictive value and maximum accuracy. The average percentage IOPTH drop observed at 5 min post‐excision was 79·8%. Kinetic analysis showed a mean half‐life of PTH of 2·57 ± 0·27 min (range: 0·07–11·55).</p> </sec> <sec id="cen12067-sec-0004" sec-type="section"> <title>Conclusion</title> <p>IOPTH monitoring is reliable even in patients with extremely high baseline IOPTH value, with a greater percentage drop at 5 and 10 min post‐excision. In patients with high baseline IOPTH, a 50% decay in PTH value at 5 min may be indicative of cure, obviating the need for 10 and 15 min samples. IOPTH kinetics are altered by adenoma weight but not affected by vitamin D status or baseline IOPTH levels.</p> </sec> </abstract>