Postoperative Parathyroid Hormone Research Articles

A prospective cross-sectional study on hypocalcemia after total thyroidectomy in patients with Graves' disease: insights on secondary hyperparathyroidism.

To investigate the parathyroid function and calcium (Ca) levels in the secondary hyperparathyroidism (SHPT) state in patients with Graves' disease. We examined 31 consecutive patients with Graves' disease without chronic kidney disease, who were treated with total thyroidectomy. The patients were divided into a normal parathyroid hormone (PTH) group (NPTH group; n = 19) with a PTH level ≤ 65pg/mL, and a secondary hyperparathyroidism group (SHPT group; n = 12), with a PTH level > 65pg/mL. The PTH and Ca-related parameters were examined and the risk factors for postoperative hypocalcemia were analyzed. The preoperative Ca level was significantly lower (2.24 ± 0.06 vs. 2.31 ± 0.07mmol/L, p < 0.05) in the SHPT group than in the NPTH group. The reduction in PTH, 1,25-dihydroxyvitamin D (1,25(OH)2D), and Ca levels from the preoperative day to the next morning was significantly greater in the SHPT group than in the NPTH group (p < 0.05). When intraoperative factors were included, the decrease in the PTH level alone was significant. SHPT was a significant factor in determining the extent of PTH reduction. Hyperfunctioning parathyroid glands in the SHPT state were more susceptible to postoperative PTH reduction, which, combined with low preoperative Ca levels, increased the risk of postoperative hypocalcemia in patients with Graves' disease.

Postoperative parathyroid hormone (PTH) is equivalent to perioperative PTH drop in predicting postsurgical hypoparathyroidism.

Postoperative surgical hypoparathyroidism (PoSH) following thyroid surgery is an established complication. Several predictive factors have been identified including perioperative parathyroid hormone (PTH) levels. The aim of the study is to compare the drop in perioperative PTH to postoperative day 1 PTH in predicting hypocalcaemia and hypoparathyroidism. Records of consecutive patients who had either total or completion thyroidectomy with or without central neck dissection in a 3-year period in a single thyroid surgery unit were accessed to retrieve data on demographics, pathology, surgery, perioperative biochemistry and management. Of 295 included patients, there were 227 (76.9%) females. Forty-five (15.3%) had completion thyroidectomy, and the rest had total thyroidectomy. Seventy-eight (26.4%) had concomitant central neck dissection. Sixty-four (21.7%) had hypocalcaemia on the day after surgery. Hypoparathyroidism persisted in 10.5% of patients at 6 months. Both day 1 PTH and a drop in PTH predicted day 1 hypocalcaemia (p < 0.001) and 6-month hypoparathyroidism (p < 0.001). The area under the receiver operating characteristic (ROC) curves for day 1 PTH and drop in PTH for the prediction of day 1 hypocalcaemia (0.729 vs 0.726, respectively) and for 6-month hypoparathyroidism (0.964 vs 0.958, respectively) were similar, albeit slightly better for day 1 PTH. Day 1 PTH is equivalent to (if not better than) drop in PTH in predicting short- and long-term PoSH. Preoperative PTH measurements may not be needed in the detection and/or management of PoSH after thyroid surgery.

Clinical characteristics and outcomes of patients operated for primary hyperparathyroidism at Tampere University Hospital in 2017-2018.

Studies on the outcomes of parathyroid surgery are scarce. The aim was to report the outcomes and to study the association between pre- and peri-operative information with the outcomes of patients operated for primary hyperparathyroidism. This was a retrospective, descriptive study with unselected patients treated surgically for primary hyperparathyroidism from a catchment population of 704,500 in Finland. Data were acquired from the electronic hospital registers based on parathyroid surgery procedure codes between 1 January 2017 and 31 December 2018. Preoperative data, surgical data, preoperative and postoperative laboratory values, histopathological findings, and postoperative clinical data were recorded. During the 2-year study period, 149 patients with primary hyperparathyroidism were treated surgically with a 97% remission rate. Surgical complications included postoperative bleeding in two patients (1%) and vocal cord paralysis in one patient (0.6%). No postoperative infections were reported. Three patients (2%) developed postoperative hypoparathyroidism necessitating the use of alfacalcidol more than 1 month after surgery. Ionized calcium measured 0-1 days after surgery was not statistically significantly associated with remission or postoperative hypoparathyroidism. Serum parathyroid hormone (PTH) assessed 0-1 days postoperatively was associated with persistent disease, but not with postoperative hypoparathyroidism. The histopathological diagnosis was adenoma or hyperplasia in 112 patients (75%), atypical adenoma in 28 patients (19%), and carcinoma in five patients (3%). Patients with parathyroid carcinoma had higher preoperative ionized calcium and PTH values than those with adenoma or hyperplasia. Most patients who were operated due to primary hyperparathyroidism achieved normocalcemia after surgery, and the frequency of complications was low. Ionized calcium taken 0-1 days after surgery was not associated with remission of hyperparathyroidism or postoperative hypoparathyroidism. High postoperative serum PTH predicted persistent disease.

Post-thyroidectomy hypocalcemia in Saudi Arabia: a review of incidence rates and risk factors

Post-thyroidectomy hypocalcemia is a frequent and variable complication in Saudi Arabia, which can extend hospital stays and raise healthcare costs. A systematic search was performed using databases for studies published before January 2024 documenting hypocalcemia rates in Saudi Arabian adults following thyroidectomy. Eighteen studies met our criteria, encompassing 3,455 patients. The analyses revealed substantial variability across included studies in terms of sample size, design, and reported hypocalcemia rates. Overall rates ranged from 0.07% to 67.4% (averaging 24.4%), with transient cases being more prevalent (averaging 26.8%). Permanent hypocalcemia rates were lower (averaging 1.3%, ranging from 0% to 3.7%). Preoperative and postoperative parathyroid hormone (PTH) levels consistently predicted hypocalcemia. Additional potential contributing factors included the number of parathyroid glands (PGs) identified during surgery, gender, pre-surgical hyperthyroidism, and surgical expertise and experience. These findings translate to several implications for surgical practice and patient management. Close monitoring of PTH levels holds significant importance. Selective identification of PGs during surgery might decrease the risk of hypoparathyroidism. In addition, surgeon training and supervision are pivotal for achieving optimal outcomes. Identifying patients at risk for hypocalcemia early might facilitate earlier discharge. In conclusion, post-thyroidectomy hypocalcemia poses a variable and widespread complication in Saudi Arabia. Comprehending its risk factors and implementing targeted strategies have the potential to improve patient management and outcomes.

Risk factors for postoperative hypocalcemia following total thyroidectomy: a retrospective study.

and Objectives: Hypocalcemia is a commonly reported complication after thyroid surgery. Many possible risk factors have been identified. The purpose of this study is to analyze various risk factors possibly associated with development of postoperative hypocalcemia after thyroid surgery by dividing the sample population into postoperative hypocalcemia and normal calcium groups. Retrospective. Multiple centers in the Makkah region of Saudi Arabia. Risk factors for postoperative hypocalcemia that were obtained for analysis include patient factors, perioperative blood parameters factors, disease-related factors, and surgical factors. Postoperative hypocalcemia was defined as a reduction of the total calcium level to <8.0 mg/dL. Hypocalcemic and normocalcemic patients were compared by multivariate logistic regression. Distinguish independent risk factors for postoperative hypocalcemia after thyroidectomy. 215 patients. The incidence of hypocalcemia was 52.1% (112 of 215 patients). According to multivariate analysis, statistically significant risk factors for predicting postoperative hypocalcemia included postoperative parathyroid hormone level <10 pg/dL, inadvertent parathyroid gland resection, and neck dissection surgeries. The causes of postoperative hypocalcemia are multi-factorial. Because many of these factors are modifiable, they should be identified postoperatively to distinguish high-risk groups and implement early preventive measures. Retrospective with a relatively small size. We encourage additional prospective studies with a larger sample size in multiple regions of the country, which might reveal further significant results.

Intraoperative prevention of postoperative hypoparathyroidism.

More than 30,000 thyroid surgeries are performed annually in the Russian Federation. The surgeries are relatively safe because of the prevention methods for postoperative complications. Currently, there is no single effective method of postoperative hypoparathyroidism prevention. This complication is frequently reported and may be health and life-threatening. We aimed to estimate the effectiveness of the intraoperative ICG-angiography and intrathyroid injection of Brilliant Green for the prevention of postoperative hypoparathyroidism. One hundred and forty-three thyroidectomies were performed. Patients were divided into three groups: intraoperative angiography was used in 24 cases; Brilliant Green was injected in 58 cases to identify parathyroid glands; the visual estimation of the parathyroid preservation was used in 61 cases. Calcium level was measured in all patients before and after surgery. Calcium level in the serum before and after surgery was 2.37±0.14 and 2.27±0.17 in Group 1, 2.38±0.16 and 2.21±0.16 in Group 2, and 2.39±0.17 and 2.18±0.19 in Group 3. Postoperative hypocalcemia was more prominent in the group with the visually estimated PTG than in the two other groups. The differences in postoperative calcium levels in Groups 1 and 3 were statistically different. Pre- and postoperative Parathormone levels were 6.2±0.4 in Group 1, 5.6±0.57 in Group 2, and 3.5±0.32 in Group 3. Postoperative levels significantly differed in Groups 1 and 3 (p<0.01) and in Groups 2 and 3 (p<0.05). ICG-angiography and intrathyroid injection of the Brilliant Green are safe methods of identification and sparing of the parathyroid glands. The severity of hypocalcemia and hypoparathormonemia in Group 3 shows the necessity of finding new methods in endocrine surgery to improve patient outcomes.

Surgical management of neonatal severe hyperparathyroidism.

Neonatal severe hyperparathyroidism (NSHPT) is a rare disease that can be lethal. Most patients require parathyroidectomy. Report experience in managing this severe disease. Retrospective chart review of case series. Tertiary health care center. We reviewed data on patients managed for NSHPT from June 2001 to January 2023. Demographic, clinical, and follow-up data were collected, and descriptive data were generated. Pre- and postoperative levels of parathyroid hormone (PTH) and serum calcium, and effect of autotransplantation. 19 RESULTS: The 13 males and 6 females had a a mean age of 46 days at referral. The mean preoperative parathyroid hormone (PTH) and serum calcium levels were 996 ng/L and 4.54 mmol/L, respectively. Twelve patients underwent ultrasonography preoperatively. Of these, six had prominent glands, while no glands were seen in the other six. A Sestamibi scan was done for 15 patients, of which nine showed negative results and six showed positive results, with three glands observed in the neck and three in the sublingual area. Nineteen patients underwent renal ultrasonography, with nine showing nephrocalcinosis. The mean age at surgery was 5.2 months. Total parathyroidectomy (four glands) was performed in 17 patients, and 15 underwent concurrent auto-transplantation. One patient had three glands removed, in addition to auto-transplantation. Another underwent single gland excision as a redo-surgery after previous surgery elsewhere. The mean postoperative follow-up duration was 6 years. The mean postoperative PTH and calcium levels were 25 ng/L and 1.64 mmol/L, respectively. Ultimately, all the patients were required to initiate calcium and vitamin D supplements, except for two patients who had undergone auto-transplantation. Molecular genetic screening of the calcium-sensing receptor gene reported likely pathogenic/pathogenic mutations in 16 of 19 patients (13 were homozygous, two were heterozygous, one was negative, and data was unavailable for the remaining three patients). Surgical treatment of NSHPT is effective. Preoperative radiological localization studies did not impact the treatment plan. Auto-transplantation proved ineffective in maintaining independence from medical supplements. The retrospective nature of the study may imply inaccuracybut since the data are gathered from electronic medical records, we believe it is highly accurate. The small sample size limits generalizability.

Impact of autofluorescence for detection of parathyroid glands during thyroidectomy on postoperative parathyroid hormone levels: parallel multicentre randomized clinical trial.

Techniques for autofluorescence have been introduced to visualize the parathyroid glands during surgery and to reduce hypoparathyroidism after thyroidectomy. This parallel multicentre RCT investigated the use of Fluobeam® LX to visualize the parathyroid glands by autofluorescence during total thyroidectomy compared with no use. There was no restriction on the indication for surgery. Patients were randomized 1 : 1 and were blinded to the group allocation. The hypothesis was that autofluorescence enables identification and protection of the parathyroid glands during thyroidectomy. The primary endpoint was the rate of low parathyroid hormone (PTH) levels the day after surgery. Some 535 patients were randomized, and 486 patients received an intervention according to the study protocol, 246 in the Fluobeam® LX group and 240 in the control group. Some 64 patients (26.0 per cent) in the Fluobeam® LX group and 77 (32.1 per cent) in the control group had low levels of PTH after thyroidectomy (P = 0.141; relative risk (RR) 0.81, 95 per cent c.i. 0.61 to 1.07). Subanalysis of 174 patients undergoing central lymph node clearance showed that 15 of 82 (18 per cent) in the Fluobeam® LX group and 31 of 92 (33 per cent) in the control group had low levels of PTH on postoperative day 1 (P = 0.021; RR 0.54, 0.31 to 0.93). More parathyroid glands were identified during operation in patients who had surgery with Fluobeam® LX, and fewer parathyroid glands in the surgical specimen on definitive histopathology. No specific harm related to the use of Fluobeam® LX was reported. The use of autofluorescence during thyroidectomy did not reduce the rate of low PTH levels on postoperative day 1 in the whole group of patients. It did, however, reduce the rate in a subgroup of patients. Registration number: NCT04509011 (http://www.clinicaltrials.gov).

Neck Reoperation for Recurrent or Persistent Renal Hyperparathyroidism.

Patients with renal hyperparathyroidism undergoing parathyroidectomy may experience relapse. Reoperation for persistent or recurrent disease, particularly in the neck region, is challenging and has a high complication rate because of difficult exploration. We aimed to evaluate the effectiveness of neck reoperation in renal hyperparathyroidism. Patients with recurrent or persistent renal hyperparathyroidism who underwent neck reoperation between January 2015 and August 2022 were investigated, focusing on operative findings, perioperative biochemical changes, and significance of intraoperative parathyroid hormone (PTH) measurements. During reoperation, 35 parathyroid glands were identified and removed from the 26 enrolled patients, with one, two, and three glands retrieved from 19 (73.2%), five (19.2%), and two (7.6%) patients, respectively. Most removed glands (68.6%) were located in the lower neck, followed by the mediastinum, carotid sheath, and upper neck. Successful resection, defined as a postoperative PTH level of <300pg/mL, was achieved in 21 patients (80.8%). The remaining four (15.4%) and one (3.9%) patients were classified as having persistent and recurrent disease, respectively. The extent of PTH reduction was correlated with specimen weight, specimen volume, and preoperative alkaline phosphatase (ALP) level. The mean intraoperative PTH ratio (10 min after excision/pre-excision) was 0.23, and all patients with persistent or recurrent disease had a PTH ratio >0.3. Severe hypocalcemia (<7.5mg/dL) occurred in 19 (73.0%) patients after reoperation. Neck reoperation is an effective therapeutic option in patients with recurrent or persistent renal hyperparathyroidism. A decrease in PTH level by >70% during reoperation (PTH ratio <0.3) predicts successful resection.

Comparison of clinical effects of endoscopic thyroidectomy using the modified gasless transsubclavian approach and traditional open surgery for cN0 unilateral papillary thyroid carcinoma

Objective: To compare the clinical effects of endoscopic thyroidectomy using a modified gasless transsubclavian approach and the traditional neck approach for unilateral papillary thyroid carcinoma (cN0). Methods: The clinical data of 135 patients with cN0 papillary thyroid carcinoma who underwent unilateral thyroidectomy in the Department of Thyroid Surgery, the First Hospital of Jilin University from October 2020 to November 2022 were retrospectively analyzed. There were 37 males and 98 females, aging (43.2±8.8) years (range: 21 to 59 years). There were 51 cases using the modified gasless transsubclavian approach (TS group) and 84 cases using the traditional neck approach (TN group). Comparative analyses were performed between the operative results of the 2 groups by t-test, Wilcoxon rank sum test, and χ2 test. Results: All endoscopic operations were successfully completed without conversion to the traditional neck approach. Compared to the TN group, the TS group had a longer operation time (M(IQR)) (73.5 (22.5) minutes vs. 90.0 (30.0) minutes, Z=-5.831, P<0.01), more postoperative drainage (60 (25) ml vs. 95 (45) ml, Z=-6.275, P<0.01), higher hospitalization costs (22 687 (3 488) yuan vs. 26 652 (2 431) yuan, Z=-6.944, P<0.01), and a higher rate of parathyroid autotransplantation (15.5% (13/84) vs. 60.8% (31/51), χ2=29.651, P<0.01). There was no significant difference in the total exposure rate of the central compartment, postoperative hospitalization time, the number of dissected lymph nodes, the number of metastatic lymph nodes, C-reactive protein ratio before and after operation, and preoperative and postoperative parathyroid hormone (all P>0.05). Conclusion: Endoscopic thyroidectomy using the modified gasless transsubclavian approach is safe for cN0 papillary thyroid carcinoma, with longer operating time, more postoperative drainage, higher hospitalization costs, and more difficulty in preserving the inferior parathyroid gland in situ compared to traditional open surgery.

A symptom-based algorithm for calcium management after thyroid surgery: a prospective multi-center study.

Evidence based treatment guidelines for the management of post-thyroidectomy hypocalcemia are absent. The aim of this study was to evaluate a newly developed symptom-based treatment algorithm including a protocolized attempt to phase out supplementation. In a prospective multicenter study, patients were treated according to the new algorithm and compared to a historical cohort of patients treated with a biochemically-based approach. The primary outcome was the proportion of patients receiving calcium and/or alphacalcidol supplementation. Secondary outcomes were calcium-related complications and predictors for supplementation. 134 patients were included prospectively, and compared to 392 historical patients. The new algorithm significantly reduced the proportion of patients treated with calcium and/or alphacalcidol during the first postoperative year (OR 0.36 [95% CI 0.23 - 0.54], p<0.001), and persistently at 12 months follow-up (OR 0.51 [0.28 - 0.90], p<0.05). No severe calcium-related complications occurred, even though calcium-related visits to the emergency department and readmissions increased (OR 11.5 [4.51 - 29.3], p<0.001) and (OR 3.46 [1.58 - 7.57], p<0.05), respectively. The proportional change in pre- to postoperative parathyroid hormone (PTH) was an independent predictor for supplementation (OR 1.04 [1.02 - 1.07], p<0.05). Symptom-based management of post-thyroidectomy hypocalcemia and a protocolized attempt to phase out supplementation safely reduced the proportion of patients receiving supplementation, although the number of calcium-related hospital visits increased. For the future, we envision a more individualized treatment approach for patients at risk for delayed symptomatic hypocalcemia, including the proportional change in pre- to postoperative PTH.

PARATHYROID HORMONE ASSAY IN PREDICTING POST OPERATIVE HYPOCALCEMIA AFTER TOTAL THYROIDECTOMY

Objectives: Injury to the parathyroids during thyroidectomy leads to either transient ischemia or even infarction of the glands which results in hypocalcemia. Early identification of post-operative hypocalcemia after thyroidectomy can be achieved by assessing parathormone (PTH) level. The present study correlates post-operative serum PTH at 4 h with serum calcium levels after total thyroidectomy and subsequent development of hypocalcemia. This study thus aims to determine the efficacy of parathyroid hormone assay in predicting post-operative hypocalcemia after total thyroidectomy. Methods: After obtaining approval for the study from the Institutional Review Board, patients admitted in surgery department of Kottayam medical college for total thyroidectomy are evaluated with post-operative PTH levels at 4 h after surgery and serial monitoring of serum calcium levels. Patients are evaluated clinically for signs and symptoms of hypocalcemia and their association is studied. Results: 20% of the study population developed hypocalcemia. Intact PTH was found to be lower in patients who developed symptoms of hypocalcemia. There was a statistically significant correlation between the two groups. A 4-h intact PTH value of 14 pg/mL was found to have high sensitivity (93.8%) and specificity (91.6%). Conclusion: Hypocalcemia is one of the most feared complications after total thyroidectomy. Intact PTH measurement 4 h after total thyroidectomy can be used to predict the incidence of hypocalcemia after total thyroidectomy. Therefore, patients having low 4-h intact PTH value could be started on calcium supplementation and those having high PTH could be safely discharged early.

The Obesity Paradox in Thyroid Surgery: Is Higher BMI Protective Against Hypoparathyroidism?

With a demonstrated association between adiposity and parathyroid hormone (PTH) levels, we hypothesized that patients with a higher body mass index (BMI) would have lower rates of postoperative hypoparathyroidism following total thyroidectomy. retrospective review of patients undergoing total thyroidectomy from 2015 to 2021. Demographics, BMI, surgical indications, and laboratory data including pre- and postoperative PTH values were examined. Of the 352 patients with complete clinicopathologic data, most were female (n = 272, 77.3%) with an average age of 42.7 (SD+/-19.4). Obese (BMI 30-39.99) was most common BMI group (n = 108, 30.8%), with 11.7% (n = 41) morbidly obese (BMI > 40). Morbidly obese patients had significantly higher postoperative PTH levels than BMI < 18.5 (46.0 vs 19.3pg/mL, P = .004). Patient race was significantly associated with pre- and postoperative PTH (P = .03, P = .004.) On multivariable analysis, preoperative PTH, race, and BMI were independent predictors of higher postoperative PTH (P < .05 for all). Patients with higher BMI and non-white race have relative protection from postoperative hypoparathyroidism.

Early postoperative PTH level following total thyroidectomy as a predictor of hypocalcemia: a single center-based study in Bangladesh

Background: Assessment of parathyroid hormone (PTH) following thyroid surgery assists in the prediction of hypocalcemia and permits early intervention and therapy with oral calcium and/or vitamin D supplements.&#x0D; Methods: This retrospective analysis comprised 141 individuals who had undergone a total or completion thyroidectomy over the previous four years. The blood PTH level was measured 3 hours after surgery to determine its change and to predict hypocalcemia.&#x0D; Results: Patients were predominately female (75.2%), and the mean age was 48.73 ± 13.44 years. The main surgical procedure was total thyroidectomy (80.14%), and the main cause for surgery was a multinodular goiter (34.04%). A comparable number of patients with each type of thyroid disease (multinodular goiter, papillary thyroid cancer, thyroiditis, Graves’ disease or toxic multinodular goiter were enrolled. Three hours after surgery 93 patients (65.95%) had serum PTH levels of &gt;10 pg/ml (mean 28.06) and 90 patients (68.38%) had normal serum calcium (mean 8.66). Most of these 93 patients (65.95%) didn't require postoperative supplementation, whereas 48 patients (34.05 %) with serum PTH levels less than 10 pg/ml required some form of supplementation; 39 (27.65 %) required both oral calcium and vitamin D supplements, and 9 (6.4 %) required only oral vitamin D supplementation. There was a significant correlation between the 3-h postoperative PTH level and hypocalcemia (P-value 0.000). The type of pathology had no significant association with low serum PTH level after surgery (P-value 0.166).&#x0D; Conclusion: Asymptotic individuals with PTH levels less than 10 pg/ml, who are regarded as being in the high-risk category, can start taking calcium and/or vitamin D supplements early if their PTH levels are measured at 3 hours following complete thyroidectomy. To predict hypocalcemia, more research is required to compare the outcome of early serum PTH level with the day one serum PTH level following complete thyroidectomy.&#x0D; Central Medical College Journal Vol 6 No 2 Jauly 2022 Page: 82-89

The Relationship of Solitary Parathyroid Adenoma Volume with Pre- and Post-operative Parathormone and Calcium Levels

Objective: Parathyroid size, weight, position and histopathological characteristics have been investigated as possible candidates of predictive value. We aimed to investigate the relationship between the volume of the parathyroid gland as calculated by sonographic measurements and the amount of postoperative decrease in serum calcium and parathyroid hormone (PTH) levels .&#x0D; Materials and Methods: Preoperative and postoperative plasma levels of corrected calcium and intact PTH were noted. The size of each adenomatous parathyroid gland was calculated as an ellipsoid based on the preoperative sonographic measurements using the formula “V=π/6 x diameters”. &#x0D; Results: A total of 61 (76.3%) females and 19 (23.8%) males were included in the study. The median age of the patients was 58 years. The average volume of the adenomatous parathyroid gland was calculated to be 13.4 cm3. Plasma levels of both calcium and PTH significantly decreased following surgery (p:0.000, p:0.000, respectively). There was significant correlation between the adenoma volume and the change in calcium value (r: -0.500, p:0.000) but not for the PTH value (r: 0.036, p:0.750).&#x0D; Conclusion: Our significant results may suggest a relationship between the volume of adenoma and plasma calcium levels, but more extended studies with larger patient groups are needed for more consistent results.

Postoperative Serum Parathyroid Hormone Levels as a Predictor of Hypocalcemia in Patients Undergoing Total Thyroidectomy.

Postoperative hypocalcemia is a common complication of total thyroidectomy; the onset and severity of post-operative hypocalcemia is unpredictable. Various attempts have been made to identify predictors of hypocalcemia. There has been an increasing interest in serum levels of parathyroid hormone (PTH) as an early predictor of the development of hypocalcemia after total thyroidectomy. However, there is no consensus on the time intervals and cut-off levels of serum PTH to predict hypocalcemia. In this study, we intend to use serum PTH levels at 4th and 12th hour after total thyroidectomy to identify patients at risk of developing Postoperative hypocalcemia and to evaluate the role of PTH in predicting hypocalcemia. A Cross sectional analytical study conducted in 33 patients undergoing total/completion thyroidectomy from December 2018 to May 2020. Serum total calcium, Serum ionized calcium and Serum intact PTH levels were measured on three occasions (Preoperative and 4th and 12th hour Postoperative). Between both Postoperative levels of PTH, the one with better predictability of hypocalcemia was determined. Postoperative 4th hour PTH is a better predictor of transient hypocalcemia than Postoperative 12th hour PTH, as the association of the former with serum ionized calcium level was statistically highly significant with p value 0.005 and 0.021 respectively. Serum PTH determination after four hours of total thyroidectomy is a relatively better predictor of transient hypocalcemia, and can guide calcium supplementation for those at high risk in the Postoperative period. However, to determine the risk of hypocalcemia at the end of 1month of follow-up, both the Postoperative 4th and post-operative 12th hour PTH have similar diagnostic accuracy.

Abstract #1398160: A Rare Case of Water Clear Cell Parathyroid Adenoma Escaping Sestamibi Scan and Neck Ultrasound – A Diagnostic Conundrum of a Rare Pathological Intity with a Rare Presentation

Parathyroid water-clear cell hyperplasia (WCCH) and water-clear cell adenoma (WCCA) are extremely rare causes of primary hyperparathyroidism (PHPT). WCCH contributes to < 1% of all PHPT however WCCA is exceptionally rare and has been reported only in less than 30 case reports. We are presenting a very rare indolent pathological entity with a very rare presentation escaping common diagnostic measures of Sestamibi scan and neck ultrasound. A 63-year-old female presented for evaluation of severe osteoporosis with a T-score of -3.6. Laboratory workup revealed elevated parathyroid hormone (PTH) of 122 pg/ml (reference range 12-88 pg/ml), Normal calcium 9.8 mg/dl, Normal vitamin D 50 ng/ml, and normal magnesium 2.2 mg/dl. 24-hour urine calcium was 421 mg/24H. Diagnosis was consistent with normocalcemic PHPT and meeting surgical criteria with osteoporosis and high urine calcium. Sestamibi scan did not identify any focal activity. CT H&N revealed an 8 mm mass inferior and posterior to right thyroid lobe with partial washout and slightly different enhancement compared to thyroid gland. Neck ultrasound (US) reported that previously noted tissue activity on the CT H&N is not visualized and most likely represents normal thyroid tissue. Patient was referred to otolaryngology surgery and underwent four gland explorations, including right inferior and left superior parathyroidectomy. Pathology of superior parathyroid gland revealed parathyroid water clear cell adenoma. 3-month Postoperative PTH 29.4 pg/ml and calcium level of 9.3 mg/dl. Solitary parathyroid adenoma (SPA) attributes to 80-85% of PHPT. Majority of cases is due to Chief cell adenomas, less frequent pathologies include oxyphil cell adenoma, lipoadenoma, WCCA or mixed type. Scientific literature regarding WCCA presentation and diagnosis is blurred due to its rarity. Clinical presentation of WCCA resembles other etiologies of PHPT, though some data suggest that is frequently indolent and manifests with mild PHPT. Literature suggests that WCCA has low biochemical activity and most cases had normal to mildly elevated calcium-our patient support this hypothesis-. Hypercalcemia does not manifest until significant growth of the adenoma, though few reported cases manifested with hypercalcemia. Unlike other SPA where Sestamibi scan sensitivity is 91%, literature suggests possibility of false-negative results with WCCA which is hypothesized to be attributed to its different histology of glycogen-rich vacuolized cytoplasm that leads to fast Sestamibi wash-out, for the same reason data suggest that US is more decisive given high water content of cells -Our patient didn’t follow this rule and escaped Sistamibi and US though seen on CT- which still makes the diagnosis of WCCA a conundrum. Some cases underwent surgical excision based on clinical diagnosis which led to revision of PHPT and/or hypercalcemia. There is no available data suggesting different long-term follow-up regimens for WCCA compared to other SPA. Further literature with longer follow-up is needed for this extremely rare entity for a comprehensive understanding of its natural course.

Revision Parathyroid Surgery - Challenges and Considerations in Comparison to Primary Surgery.

Revision parathyroidectomy is made necessary by recurrent or persistent parathyroid disease. This study aimed to identify challenges in revision surgery compared to primary parathyroid surgery. All revision parathyroidectomies performed by one surgeon over a 17-year period were assessed for demographics, imaging, histology, biochemistry, cure rate, gland weight, gland location and gland ectopia, and compared to a series of 100 primary parathyroidectomies. Twenty-eight revision surgical procedures were identified. Sestamibi scanning for gland localisation was superior to ultrasound in both primary and revision surgery. Pre-operative calcium and gland weight were significantly higher in revision cases. There were no significant differences in post-operative calcium levels, pre- or post-operative parathyroid hormone levels, or gland location. 36 per cent of glands excised in revision surgery were ectopic, compared to 25 per cent in primary procedures. The cure rate was significantly lower in revision surgery. Revision parathyroidectomy patients present with higher pre-operative calcium and larger adenomas; the cure rate is significantly lower in these patients.

Serum Parathyroid Hormone and Vitamin D Levels as Predictors of Hypocalcemia after Total/ Near Total Thyroidectomy

Background: Post-operative Hypocalcaemia is the most-common complication of total and near-total thyroidectomy which is a selective treatment for benign and malignant thyroid diseases. Incidence ranges from 0.5-50%. Objectives: The role of vitamin-D and Parathyroid hormone(PTH) in incidence of Hypocalcemia after thyroidectomy has been taken into consideration. Methods: This is a prospective interventional study is conducted in Kasturba Medical College and hospital, Manipal after taking written informed consent from the participants. It aimed at surveying the serum level of preoperative Vitamin D, PTH and calcium before total-thyroidectomy surgery and its relationship with the incidence of postoperative hypocalcemia after the surgery. The study was done on 70 patients who were-planned for total/near total thyroidectomy. Preoperative Vitamin D, PTH, calcium and Postoperative 4 hours-PTH, Calcium were measured on POD-1, POD-2-4, the results obtained were then analysed. Results: Considering the cut-off of calcium as 8.6mg/dl, 42 patients developed hypocalcemia on POD-1, 28 patients on POD-2. Preoperative calcium and postoperative PTH levels in people having hypocalcaemia where significantly less compared to the patients having normal calcium. 4-hours post-operative PTH measurements showed 51% sensitivity, 100% specificity and strong co-relation between postoperative hypocalcemia and drop in PTH levels- (p=<0.001). Out of 42 patients who developed hypocalcemia 28- (65%) patients had vitamin-D deficiency(p=0.5) on POD-1 and out of 51 patients with hypocalcemia on POD 2-4, 33(78%) had-vitamin-D-deficiency(p=0.3852). Which was not statically significant. Conclusion:4 hours post-operative PTH level is a predictor of early postoperative hypocalcemia, by detecting this we can effectively manage postoperative hypocalcemia

Risk Factors for Hypoparathyroidism after Thyroid Surgery: A Single-Center Study

Hypoparathyroidism is one of the most common complications after thyroidectomy. This study evaluated the incidence and potential risk factors for postoperative hypoparathyroidism after thyroid surgical procedures in a single high-volume center. In this retrospective study, in all patients undergoing thyroid surgery from 2018 to 2021, a 6 h postoperative parathyroid hormone level (PTH) was evaluated. Patients were divided into two groups based on 6 h postoperative PTH levels (≤12 and >12 pg/mL). A total of 734 patients were enrolled in this study. Most patients (702, 95.6%) underwent a total thyroidectomy, while 32 patients underwent a lobectomy (4.4%). A total of 230 patients (31.3%) had a postoperative PTH level of <12 pg/mL. Postoperative temporary hypoparathyroidism was more frequently associated with female sex, age < 40 y, neck dissection, the yield of lymph node dissection, and incidental parathyroidectomy. Incidental parathyroidectomy was reported in 122 patients (16.6%) and was correlated with thyroid cancer and neck dissection. Young patients undergoing neck dissection and with incidental parathyroidectomy have the highest risk of postoperative hypoparathyroidism after thyroid surgery. However, incidental parathyroidectomy did not necessarily correlate with postoperative hypocalcemia, suggesting that the pathogenesis of this complication is multifactorial and may include an impaired blood supply to parathyroid glands during thyroid surgery.