Comparison between Rapid Intraoperative and Central Laboratory Parathormone Dosage in 12 Kidney Transplant Candidates

Abstract

Background The rapid intraoperative parathormone (PTH) and at central laboratory PTH dosage gives similar results. The central laboratory provides results in longer times and higher costs. Intraoperative measurement can reduce time and costs during parathyroidectomy. Methods Twelve patients undergoing parathyroidectomy for hyperparathyroidism renal transplant candidates were included. Diagnosis was made by laboratory tests (serum calcium, PTH) and imaging techniques (ultrasonography and scintigraphy). All patients presented PTH levels of >400 pg/mL (the limit value to be maintained in list for kidney transplantation) and resistant to medical therapy. For each patient, 2 blood samples were collected before surgery at anesthesia induction for PTH testing intraoperative (rapid assay) and central laboratory, and 10 minutes after the removal of each gland. The times from collection-processing to communication to the surgeon of the results were compared for both the methods. It was considered successful the abatement of PTH of ≥70% at rapid intraoperative testing and consequently surgical intervention stopped before communication of central laboratory PTH testing. Results The average time of reporting the test results of the central laboratory was 41.5 minutes (SD ± 9), whereas with the rapid intraoperative PTH (ioPTH) testing the average time was 9.9 minutes (SD ± 2.02). An average of 33.6 minutes of the duration per intervention (SD ± 10.27) were virtually saved with the use of ioPTH testing. The 2 values of the Pearson correlation (ρ) of 0.99 obtained (for baseline) and 0.975 (for the 10-minute) lead us to conclude that there is an excellent correlation between the series of data. Conclusions Rapid ioPTH testing, owing to its accuracy, permits a dramatic reduction of operating time for patients with secondary hyperparathyroidism that need to be treated before inclusion on the waiting list.