Intraoperative Parathyroid Hormone Testing Research Articles

Association of Implementation of Operating Room-Based Parathyroid Hormone Testing with Operative Time and Cost.

Intraoperative parathyroid hormone (IOPTH) testing facilitates focused parathyroidectomy to establish biochemical cure but may be time-consuming. A dedicated immunoassay machine was relocated to the operating room for IOPTH. These data seek to determine association of operating room-based IOPTH with operative time, laboratory turnaround time (TAT), and cost. Patients who underwent parathyroidectomy from June 2017 to February 2020 were reviewed. Clinical and demographic data, operative time, and TAT were collected. Patients were compared by operation dates pre- or post-machine acquisition. A cost model was created to evaluate cost of care before and after operating room-based testing. A total of 285 patients were included. Post-machine, median operative time decreased from 69 minutes (interquartile range [IQR] 60 to 84) to 57 minutes (IQR 50 to 84.5), p 0.03. Additionally, median TAT for IOPTH values (preoperative, 0, 5, 10, and 15 minutes) decreased post-machine: time preoperative, 29 minutes (IQR 23 to 40) vs 18 minutes (IQR 17 to 23.5), p < 0.001; time 0, 33 minutes (IQR 27 to 39) vs 18.5 minutes (17.5 to 21), p < 0.001; time 5 minutes, 31 minutes (IQR 26 to 36) vs 20 minutes (IQR 18.5 to 21), p < 0.001; time 10 minutes, 32 minutes (IQR 27 to 39) vs 20 minutes (IQR 18.5 to 22.5), p < 0.001; and time 15 minutes, 30 minutes (IQR 26 to 36) vs 19 minutes (IQR 17 to 21), p < 0.001. Total costs pre- and post-machine were $4,442 and $4,111, respectively. With $331 cost reduction per operation and 127 operations per year, the IOPTH machine pays for itself in 3 years, or 378 surgeries, and saves $168,589 in the machine's remaining 4-year life span. Operating room-based parathyroid hormone testing results in improved operating productivity by decreasing result TAT and operative time and reduces cost.

Improving Intraoperative Parathyroid Hormone Lab Efficiency.

Intraoperative parathyroid hormone (iPTH) testing is often used to confirm successful removal of hypersecreting parathyroid glands during parathyroidectomy. Unfortunately, the iPTH test can be a time-consuming and highly variable process that occurs while the patient is under anesthesia. We set out to improve iPTH lab efficiency and variability. We performed a retrospective review of 85 patients who underwent parathyroidectomy at our institution from October 2017 to October 2019. Each step of the iPTH lab reporting process was recorded and analyzed. Three simulations were performed of the entire process. We then established interventions to modify inefficiencies in the process and studied 21 patients who underwent parathyroidectomy at our institution from November 2019 to March 2020. Twenty-five minutes of time inherent to the process were identified. Four critical steps were identified as modifiable steps in the process:1. Operating room (OR) blood draw ---> lab receipt.2. Lab receipt ---> placement on centrifuge.3. Removal from centrifuge ---> placement on PTH machine.4. PTH machine result ---> OR verbal report.We improved iPTH lab efficiency by 19%, decreasing the average lab result from 45 to 36minutes (P = .001). We improved iPTH lab variability by 62%, decreasing the standard deviation from 21 to 8minutes (P = .001). Utilizing a team-based approach to identify and expedite critical steps in the iPTH lab process can make a significant improvement in iPTH lab efficiency, improving patient care by decreasing total anesthesia time.

Challenging NICE guidelines on parathyroid surgery

BackgroundNational Institute of Clinical Excellence (NICE) recommend against routinely using Intra-Operative Parathyroid Hormone (IOPTH) for first-time parathyroid surgery due to its cost and minimal surgical benefit. The European Society of Endocrine Surgeons differ from this and recommends IOPTH with conflicting pre-operative or single imaging. NICE guidance acknowledged that this may change practice in larger centres. We devised a retrospective single-centre cohort study to analyse the impact of IOPTH on decision-making and cost-effectiveness. MethodologyFirst-time parathyroidectomy procedures for primary hyperparathyroidism were assessed between 2017 and 2019. Ultrasound (US) and Sestamibi with parathyroid single-photon emission with computed tomography (SPECT-CT) were compared with IOPTH. The contribution of IOPTH to cure and cost effectiveness ratio was calculated. Results114 cases were included, with IOPTH performed in all cases, SPECT-CT in 112 and US in 108 cases. A cure rate of 99.1% (113/114) was achieved. 11.4% (13/114) of the cure rate was influenced by IOPTH (P 0.01), instigating further exploration when its levels didn't decrease. This included 7.1% (4/56) in the concordant-imaging cohort. IOPTH accuracy (96.5%) was significantly superior (P = 0.03) to both US (80%) and SPECT-CT (81%). Comparing the total costs for IOPTH testing over 2 years (£39,721) with 13 potential re-operative procedures in its absence (£63,536), a positive cost-effectiveness ratio of £1832 per re-operative procedure averted was achieved. ConclusionAbandoning IOPTH in first-time parathyroid surgery is too ambitious when weighing the cost of re-operative surgery against cost savings obtained by using routine IOPTH to achieve an improved cure rate, even in concordant imaging.

Outcomes in patients with and without intraoperative parathyroid hormone testing for primary hyperparathyroidism: A retrospective observational analysis

ObjectivesThe use of intraoperative parathyroid hormone (ioPTH) monitoring has been recommended as an adjunct to improve likelihood of successful parathyroid surgery. We sought to compare the surgical outcomes as well as operative times and associated costs in patients with and without ioPTH in the setting of co-localizing studies for primary hyperparathyroidism. MethodsA retrospective review was conducted of patients undergoing surgery for nonfamilial primary hyperparathyroidism at a single institution from January 2013 to April 2019. Patients with a suspected single adenoma that co-localized on sestamibi and ultrasound were included resulting in 141 patients, of which 110 (78%) had ioPTH testing (group 1) while 31 (22%) did not (group 2). Time driven activity-based cost (TDABC) analysis was performed incorporating physician and staff compensation and anesthetic usage to determine the cost differential between groups. Study DesignRetrospective chart review. ResultsIn group 1, the use of ioPTH prompted re-exploration in 2 patients (1.8%). In both cases, the initial gland identified was normal parathyroid and persistent elevation of ioPTH resulted in additional dissection and removal of the adenoma. All but two group 1 patients had normal post-operative calcium levels at last follow up for an overall success rate of 97.3%. One group 2 patient (3.2%) was found to have recurrent hyperparathyroidism 33 months later with an adenoma identified in the same location as the initial excision. Otherwise all group 2 patients were eucalcemic at last follow-up for an overall success rate of 96.8%. The average time for the procedure in group 1 was 91.7 ± 28.1 minutes compared to 52.3 ± 16.9 minutes in group 2 (p<0.001). Mean TDABC for group 1 was $900.93 ± 261.49 compared to $487.52 ± 157.93 for group 2 (p<0.001). ConclusionsIn patients with co-localizing sestamibi scan and ultrasound and concordant operative findings, the use of ioPTH did not improve the success rate of minimally invasive parathyroid surgery, while increasing operative times and cost.

Data on length of parathyroidectomy surgery and intraoperative parathyroid hormone (PTH) assay turnaround times following a switch in the location for intraoperative PTH testing from near point-of-care to central laboratory.

Intraoperative monitoring of parathyroid hormone (PTH) is commonly used during parathyroidectomies. There are a number of practical challenges in achieving rapid turnaround time (TAT) for intraoperative PTH testing, whether the testing is performed point-of-care, near point-of-care, or in a central clinical laboratory. In the related research article, we analyzed a decade of data from 3025 intraoperative PTH tests on 897 unique patients. Of these, 1787 tests on 514 unique patients (375 female, 139 male) occurred while intraoperative PTH measurement was done as near point-of-care testing; the remaining 1238 tests on 383 unique patients (282 female, 101 male) occurred after a switch to intraoperative PTH measurement by the hospital central laboratory. The data in this article provides the patient age, gender, location of surgery (main operating rooms vs. ambulatory surgery center), incision to close time for surgery, and operation start to end times. For the central laboratory testing, additional data are provided for the intraoperative PTH TAT. The analyzed data is provided in the supplementary tables included in this article. Plots of operation start and end times are also included. The dataset reported is related to the research article entitled “Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone” [D. Jacob, G. Lal, D.R. Voss, T. Bebber, S.R. David, J. Kulhavy, S.L. Sugg, A.E. Merrill, M.D. Krasowski, Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone, Pract. Lab. Med. (2020) 22: e00176] [1]

Evaluation of switch from satellite laboratory to central laboratory for testing of intraoperative parathyroid hormone

ObjectivesThe aim of this study was to evaluate testing turnaround time (TAT) and incision to close time in parathyroid surgeries before and after switching intraoperative parathyroid hormone (PTH) testing from a near point of care location to a central clinical laboratory. Design and MethodsThis retrospective study covered a ten-year period. Both testing locations used the same Roche Diagnostics PTH immunoassay but on different analyzers. The predominant site for surgeries was the main operating rooms (ORs) in an adjacent building, with a limited number of parathyroid surgeries performed at a more distant ambulatory surgery center (ASC). Under ideal conditions, TAT for near point-of-care testing was 20 ​min, although multiple factors could increase TAT. Incision to close time from the electronic health record was used to define time of surgery. ResultsA total of 897 unique patients were identified for which 3031 orders for intraoperative PTH were placed (383 unique patients and 1244 orders after switch in testing site). The average total TAT times for testing (mean ​± ​SD) in the central laboratory were 23.9 ​± ​16.0 ​min (median, 22 ​min) for all specimens, 22.8 ​± ​7.9 ​min (median, 21 ​min) for main OR specimens, and 26.4 ​± ​7.1 ​min (median, 25 ​min) for ASC specimens. Incision to close time for parathyroidectomies showed decreases in mean, median, and standard deviation following testing change. ConclusionsSurgery time for parathyroidectomies may remain consistent or decrease if intraoperative PTH testing is moved from a near point of care to a central laboratory.

The Total Testing Process of Intra-Operative Parathyroid Hormone. A Narrative Review.

Primary hyperparathyroidism (pHPT) is a common endocrine disorder, due to an excessive secretion of parathyroid hormone (PTH) from one or more parathyroid gland(s), where the only cure remains surgery. The surgical approach has become less invasive over the years, thanks to the advances in the preoperative localization of the enlarged parathyroid gland, as well as to the possibility to measure intra-operative parathyroid hormone (IOPTH). After the targeted removal of a parathyroid gland, IOPTH can confirm biochemically the cure of pHPT, such that it helps the surgeon to judge if the parathyroidectomy has been successful and there is no need of additional dissection. As with all laboratory tests, the quality of IOPTH total testing process is essential to the best utilization of patients' results. However, this can be affected by errors occurring in different phases. This review aims to describe the total testing process of IOPTH. We performed a search in Pubmed and a review of the literature on the current management of pHPT and the total testing process of IOPTH measurement. Compared to previous studies focusing on single aspects of the IOPTH testing process, here we have analyzed all the steps crucial for the quality of IOPTH from the "pre-pre" to the "post-post" analytical phase. Clinicians and laboratory scientists should be aware of all the potential sources of errors in IOPTH measurement in order to improve their daily management of pHPT.

Intraoperative parathyroid hormone (PTH) testing in patients with primary hyperparathyroidism and PTH levels in the normal range

BackgroundPrimary hyperparathyroidism is a common endocrine disorder. Hypercalcemia with normal PTH levels is very unusual and can lead to diagnostic difficulties. There are very few very few studies in the literature and all with limited numerical samples. The goal of the present study was to determine the real incidence and characteristics of primary hyperparathyroidism with normal PTH and to evaluate if intraoperative PTH testing is useful in these patients.MethodsWe performed a retrospective review of 314 patients who had undergone parathyroidectomy to treat primary hyperparathyroidism between January 2002 and December 2016. Patients were divided in two groups according to biochemical preoperative findings: in Group A were included patients with normal serum PTH, in Group B those with increased serum PTH.ResultsNine patients (3.7%) were included in group A and 235 in group B. Patients in group A were younger (51.5 ± 12.9 years vs 59.6 ± 12.5); preoperative serum calcium and the incidence of coexisting thyroid disease were similar between the two groups. Symptomatic patients were more frequent in Group A (77.8% vs 39.1%; p = 0.048). There were no significant differences regarding preoperative localization studies and surgical procedure. Intraoperative PTH determination demonstrated sensitivity of 86% in group A and 97% in group B, specificity and positive predictive value of 100% in both the groups, negative predictive value of 67% in group A and 79% in group B. Histopathological examination demonstrated a single gland disease in 8 (88.9%) patients in group A and a multi gland disease in 1 (11.1%), in group B single gland disease was found in 218 (92.8%) patients and multi gland disease in 17 (7.2%). Unsuccessful surgery with persistent or recurrent hyperparathyroidism occurred in 1 (11.1%) patient in group A and 4 (1.7%) in group B.ConclusionsPrimary hyperparathyroidism with normal PTH is rare but physicians should be aware of this possibility in patients with hypercalcaemia. Patients with normal PTH levels are younger and more frequently symptomatic. Intraoperative PTH testing plays an important role in the operative management even in such patients.

Focused Parathyroidectomy without Intraoperative Parathyroid Hormone Testing: Acceptability after Preoperative Localization with SPECT-CT

Focused Parathyroidectomy without Intraoperative Parathyroid Hormone Testing: Acceptability after Preoperative Localization with SPECT-CT

Intraoperative parathyroid hormone testing in primary hyperparathyroidism surgery: time for giving up?

Intraoperative PTH testing (IOPTH) in treatment of primary hyperparathyroidism (PH) is debated. Some authors advise against IOPTH in patients with concordant preoperative imaging undergoing focused parathyroidectomy. This study aims to compare focused parathyroidectomy success rates with and without IOPTH in patients with concordant preoperative imaging. Retrospective cohort study involving 599 consecutive patients underwent surgery for PH from 2012 to 2017. Patients with discordant preoperative imaging were excluded. 426 patients underwent focused parathyroidectomy (214 patients without IOPTH and 212 with IOPTH) and were considered for the statistical analysis. In case of insufficient IOPTH decay (less than 50%), a bilateral exploration was carried out. The IOPTH group and the non-IOPTH group were similar for demographics and preoperative PTH and calcaemia. 413 patients were cured and disease persistence rates between groups were not significantly different (p > 0.05). Although further testing and randomized-controlled trials are required to validate our findings, our data show that IOPTH does not seem to improve the outcome in patients with concordant preoperative imaging undergoing focused parathyroidectomy.

Disparity between Preoperative and Pre-Excisional Intraoperative Parathyroid Hormone in Parathyroid Surgery.

Introduction Intraoperative parathyroid hormone (ioPTH) testing is a widely accepted standard for assessing the parathyroid gland function. A decline of preoperative parathyroid hormone (PTH) levels by more than 50% is one accepted measure of parathyroid surgery adequacy. However, there may be a variation between preoperative PTH levels obtained at a clinic visit and pre-excisional ioPTH. Objective Our study explores the differences between preoperative PTH and pre-excisional ioPTH levels, and the potential impact this difference has on determining the adequacy of parathyroid surgery. Methods A retrospective study that consisted of 33 patients that had undergone parathyroid resection between September 2009 and March 2016 at a tertiary academic center was performed. Each subject's preoperative PTH levels were obtained from clinic visits and pre-excisional ioPTH levels were recorded along with the time interval between the measurements. Results There was a significant difference between the mean preoperative PTH and the pre-excisional ioPTH levels of 147 pg/mL (95% confidence interval [CI] 11.43 to 284.47; p = 0.0396). The exclusion of four outliers revealed a further significant difference with a mean of 35.09 pg/mL (95% CI 20.27 to 49.92; p < 0.0001). The average time interval between blood draws was 48 days + 32 days. A weak correlation between the change in PTH values and the time interval between preoperative and pre-excision blood draws was noted (r2 = 0.15). Conclusion Our study reveals a significant difference between the preoperative PTH levels obtained at clinic visits and the pre-excisional intraoperative PTH levels. We recommend routine pre-excisional intraoperative PTH levels, despite evidence of elevated preoperative PTH levels, in order to more accurately assess the adequacy of surgical resection.

Characterizing the operative findings and utility of intraoperative parathyroid hormone (IOPTH) monitoring in patients with normal baseline IOPTH and normohormonal primary hyperparathyroidism

During parathyroidectomy with intraoperative parathyroid hormone monitoring, the successful removal of a hypersecreting gland(s) resulting in normocalcemia is indicated by a >50% decrease in intraoperative parathyroid hormone level, typically into the normal range. Some patients, however, will have baseline parathyroid hormone levels within the normal range. We sought to determine the utility of intraoperative parathyroid hormone testing in these patients. We retrospectively studied all patients who underwent parathyroidectomy for primary hyperparathyroidism at our institution over a 10-year period. Overall, 317 (17%) patients had parathyroid hormone within the normal range at the onset of operation (baseline intraoperative parathyroid hormone), and 1,544 (83%) had classic primary hyperparathyroidism. The intraoperative parathyroid hormone degradation was slower in normal baseline intraoperative parathyroid hormone patients than classic primary hyperparathyroidism patients, though this did not reach statistical significance (P < .254). A >50% intraoperative parathyroid hormone decrease predicted cure in 98.7% of normal baseline patients and 98.8% of classic primary hyperparathyroidism patients (P=.810). Normal baseline patients had a lesser cure rate the longer it took to achieve a 50% decrease intraoperatively; however, the cure rate was constant at any time point the 50% decrease occurred in patients with classic primary hyperparathyroidism (P<.05). The 50% rule delineating operative cure can be applied with equal confidence to patients with normal range, baseline intraoperative parathyroid hormone. Moreover, the time at which the 50% drop is achieved impacts operative success rates in these patients.

The use of intraoperative parathyroid hormone monitoring in minimally invasive parathyroid surgery.

Introduction Surgery is the first-line management option for patients with primary hyperparathyroidism (pHPT). Minimally invasive parathyroidectomy (MIP) is now preferable but few centres offer this service, mainly because of lack of intraoperative parathyroid hormone (IOPTH) testing. The aim of this study was to identify whether the measurement of IOPTH in patients having minimally invasive parathyroidectomy for pHPT alters their management. Methods A retrospective review was carried out of 78 consecutive patients who underwent parathyroid surgery by a single surgeon with a special interest in parathyroid surgery. The clinical impact of IOPTH monitoring was recorded postoperatively in a timely manner. Serum adjusted calcium levels were checked preoperatively (on admission) and one month postoperatively; normalisation was considered a cure. Results In the setting of curative MIP, IOPTH measurement did not influence the management in any of the patients but it could have led to bilateral parathyroid exploration (BPE) in three instances. Similarly, in cases that required lengthening of the MIP incision, IOPTH results did not influence patient management although it could have led to BPE in one case. Conclusion MIP offers an effective cure for patients with hyperparathyroidism. The addition of IOPTH testing adds increased expense, operating time and risk to patients otherwise suitable for MIP.

Is intraoperative parathyroid hormone testing in patients with renal insufficiency undergoing parathyroidectomy for primary hyperparathyroidism accurate?

BackgroundOur aim was to determine whether chronic renal insufficiency (CRI) impacted intraoperative parathyroid hormone (ioPTH) monitoring during parathyroidectomy. We hypothesized that ioPTH monitoring in patients with CRI would show slower decline, but would still accurately predict cure. MethodsA retrospective review was conducted of patients with primary hyperparathyroidism who underwent curative single adenoma parathyroidectomy. The percentage of patients reaching 50% decline of ioPTH was compared between groups stratified by renal function. ResultsBetween 2000 and 2013, 950 patients met inclusion criteria. At 5 minutes, 66% of patients with CRI met curative criteria versus 77% of normal renal function patients (P = .001). At 10 minutes, 89% vs 92% met criteria (P = .073), and by 15 minutes, the gap narrowed to 95% vs 97% (P = .142), respectively. ConclusionsDespite CRI patients with primary hyperparathyroidism having slower ioPTH decline after curative parathyroidectomy, 95% met ioPTH criteria by 15 minutes. Standard ioPTH criteria can be used with CRI patients.

CaPTHUS scoring model in primary hyperparathyroidism: can it eliminate the need for ioPTH testing?

The CaPTHUS model was reported to have a positive predictive value of 100 % to correctly predict single-gland disease in patients with primary hyperparathyroidism, thus obviating the need for intraoperative parathyroid hormone (ioPTH) testing. We sought to apply the CaPTHUS scoring model in our patient population and assess its utility in predicting long-term biochemical cure. We retrospective reviewed all parathyroidectomies for primary hyperparathyroidism performed at our university hospital from 2003 to 2012. We routinely perform ioPTH testing. Biochemical cure was defined as a normal calcium level at 6 months. A total of 1,421 patients met the inclusion criteria: 78 % of patients had a single adenoma at the time of surgery, 98 % had a normal serum calcium at 1 week postoperatively, and 96 % had a normal serum calcium level 6 months postoperatively. Using the CaPTHUS scoring model, 307 patients (22.5 %) had a score of ≥ 3, with a positive predictive value of 91 % for single adenoma. A CaPTHUS score of ≥ 3 had a positive predictive value of 98 % for biochemical cure at 1 week as well as at 6 months. In our population, where ioPTH testing is used routinely to guide use of bilateral exploration, patients with a preoperative CaPTHUS score of ≥ 3 had good long-term biochemical cure rates. However, the model only predicted adenoma in 91 % of cases. If minimally invasive parathyroidectomy without ioPTH testing had been done for these patients, the cure rate would have dropped from 98 % to an unacceptable 89 %. Even in these patients with high CaPTHUS scores, multigland disease is present in almost 10 %, and ioPTH testing is necessary.

Minimally Invasive Resection for Mediastinal Ectopic Parathyroid Glands

We reviewed our experience with ectopic mediastinal parathyroidectomy. Between March 1980 and September 2010,mediastinal parathyroidectomy was performed in33 patients with hypercalcemia secondary to hyperparathyroidism. Primary hyperparathyroidism was the main diagnosis in 32 patients (97%). Technetium-sestamibi scan was used in 23 (70%) for preoperative localization. Minimally invasive resections were performed in 18 patients (55%), and 15 (45%) underwent open surgery. The most common minimally invasive surgery approach was video-assisted thoracoscopy in 9 patients (27%); the most common open approach was median sternotomy in 11 (33%). Intraoperative parathyroid hormone monitoring was used in 22 patients (67%). The ectopic glands were intrathymic in 15 patients (45%), in the aortopulmonary window in 7 (21%), and in other intrathoracic locations in the remaining 11 (33%). Parathyroid adenomas were identified in 21 patients (64%); parathyroid hyperplasia and carcinoma were identified in 9 (27%) and 3 (9%), respectively. No early mortality occurred in either group. Reoperation was required in 1 patient in the minimally invasive surgery group because of hemothorax. Morbidity occurred in 8 patients (24%), the most common of which was hypocalcemia in 4 (12%). The mean length of stay was significantly shorter in the minimally invasive surgery group (2 versus 6 days; p < 0.001) but mortality and morbidity were not statistically different between the two groups (p= 0.05). Mean follow-up was 3 ± 3.7 years. Minimally invasive mediastinal parathyroidectomy has similar outcomes to open surgery, with significantly shorter length of hospital stay.

Minimal Benefit to Subsequent Intraoperative Parathyroid Hormone Testing After All Four Glands Have Been Identified

Modern tools, such as intraoperative parathyroid hormone (IoPTH) assay, reduce operative time and extent of parathyroidectomy. However, the utility of a subsequent final set of IoPTH after all four glands are visualized remains questionable. This study was designed to determine the added value of IoPTH assay following parathyroidectomy with four-gland visualization in patients with primary hyperparathyroidism (PHPT). A retrospective review of patients who underwent parathyroidectomy for PHPT between July 2001 and February 2012 by two experienced endocrine surgeons was performed. Included were patients with operative reports indicating that all four parathyroid glands were identified. Following four-gland visualization a subsequent final set of IoPTH was measured to confirm cure. Cure was defined as at least 50 % fall by 5, 10, or 15 min postexcision compared with preincision levels. Of 1,838 patients that underwent parathyroidectomy, four glands were visualized in 238 cases (13 %). Of those patients meeting inclusion criteria with four glands visualized, the final set of IoPTH fell to cure criteria in 235 patients (98 %). An inadequate drop was documented in three (2 %) patients all of which were found to have multigland disease. Only in one patient (0.4 %) was a fifth parathyroid gland identified and resected. In all three cases, the subsequent final IoPTH did not affect the ultimate outcome or cure rate. When experienced surgeons visualize all four parathyroid glands, drawing a subsequent final set of IoPTH rarely changes the operative course and therefore serves a limited role.

The Necessity and Reliability of Intraoperative Parathyroid Hormone (PTH) Testing in Patients with Mild Hyperparathyroidism and PTH Levels in the Normal Range: Reply

The Necessity and Reliability of Intraoperative Parathyroid Hormone (PTH) Testing in Patients with Mild Hyperparathyroidism and PTH Levels in the Normal Range: Reply

A 32-Year-Old Man With Recurrent Kidney Stones and an Abnormal Chest Radiograph

A 32-Year-Old Man With Recurrent Kidney Stones and an Abnormal Chest Radiograph

The Necessity and Reliability of Intraoperative Parathyroid Hormone (PTH) Testing in Patients with Mild Hyperparathyroidism and PTH Levels in the Normal Range

To the Editor, We read with interest the article by Alhefdhi et al. [1] and discussed it in our journal club. We congratulate the authors for raising the issue of using intraoperative parathyroid hormone (PTH) monitoring in mild primary hyperparathyroidism (PHPT). Because of the mild biochemical and clinical indicators and the indolent natural course of the disease, surgical intervention and its benefits remain controversial [2]. It is particularly difficult to apply intraoperative adjuncts to decide the surgical cure of the patient when the serum PTH level is within the normal range. Very few studies have focused on this issue [3], and we believe the utility of intraoperative PTH (IOPTH) monitoring in mild PHPT needs to be studied, as the incidence of mild PHPT, common in Western countries, is also becoming prevalent in developing countries. To improve our understanding of the authors’ approach, we would like clarification on several points: First, did the authors perform preoperative localization? If so, how many of their patients were diagnosed preoperatively with multigland disease? The authors mention that they investigated the patients undergoing ‘‘standard targeted parathyroidectomy’’; we are not clear what that means. Also, how did they approach patients with multiglandular disease? It would be particularly informative to know the clinicopathological and surgical details of the five patients who did not have IOPTH decline [50% until the end of the procedure. Routine cases can be managed by any means, but the characteristics of this problem group need to be addressed for improved outcome. When it became apparent that the IOPTH level had not decreased, what was done? The reported cure rate in the present study was 100%; however, the mean preoperative serum calcium level was 10.8 ± 0.1 mg/dl, and there might have been some patients with normal serum calcium with normal serum PTH (as per the inclusion criteria) Given this possibility, how did the authors decide that operative cure had been effected, especially in those five patients with no decline in the PTH level until the end of the operation?