Autotransplantation Of Parathyroid Tissue Research Articles

#1807 Use of teriparatide to prevent severe hypocalcemia after parathyroidectomy in dialysis-dependent patients: a feasibility study

Abstract Background and Aims Hungry bone syndrome is a common postoperative complication after parathyroidectomy (PTx) for severe secondary hyperparathyroidism (SHPT). We aimed to conduct a feasibility study to assess the potential impact of teriparatide on the course of postoperative hypocalcemia after PTx in dialysis-dependent patients. Method We performed a randomized controlled pilot study in 20 dialysis-dependent patients with severe SHPT undergoing total parathyroidectomy with autotransplantation of parathyroid tissue. Patients were randomized to receive either 20 mcg teriparatide (Forsteo) subcutaneously on day 1 after surgery in addition to standard postoperative care (n=11) or standard postoperative care alone (n=9). Severe postoperative hypocalcemia was defined as an ionized serum calcium level of less than 0.8 mmol/l during the first 3 days after surgery. Results Patients in the two groups did not differ in terms of pre- and postoperative laboratory data, including PTH, corrected total calcium, ionized calcium and alkaline phosphatase levels – Table 1. Severe hypocalcemia was observed in 6 patients in the teriparatide group (55%) and in 4 patients (44%) in the control group (p=0.99). The proportion of patients with symptoms of hypocalcemia was higher in patients not receiving teriparatide (67% vs 27%, p=0.17), although these differences did not reach statistical significance. All post-PTx patients received standard supplementation according to local protocol, including calcium carbonate 20 gr/day, active vitamin D 2 mcg/day per os, and intravenous calcium gluconate supplementation on demand for symptoms of hypocalcemia (e.g. numbness, tingling, or cramps). Total elemental calcium requirement after surgery (which may serve as a surrogate for the severity of hungry bone syndrome) was higher in patients receiving standard treatment alone (41 [Q1-Q3: 33; 49] grams per hospitalization vs 33 [Q1-Q3: 25; 40] grams in the teriparatide group, p=0.0375) – Fig. 1. The total length of hospital stay was 4 ± 1 days in teriparatide group and 5 ± 2 in control group, p=0.36. Conclusion In dialysis-dependent patients after PTx, we observed a trend towards an alleviation of postoperative hypocalcemia after single injection of teriparatide in addition to routine care. Further studies with larger sample sizes are needed to confirm these preliminary results.

Chronic dialysis patient with severe secondary hyperparathyroidism undergoing parathyroidectomy in Indonesia: a case series

Link of Video Abstract: https://youtu.be/d196XKGsPekBackground: Parathyroidectomy is a method of treating secondary hyperparathyroidism associated with Chronic Kidney Disease (CKD), which has been largely abandoned in developed countries due to the existence of calcimimetic drugs which are reported to be effective in treating secondary hyperparathyroidism in this population. However, in developing countries like Indonesia, the availability of Calcimimetic drugs is still rare and expensive, so that parathyroidectomy can be an option. The study aimed to present four case reports of chronic HD patients with SHPT accompanied by clinical symptoms. As far as our knowledge goes, this is the first case series reported from Indonesia. Case Presentation: This research is a multicenter case series study. All patients had undergone dialysis for five years and complained of body aches. All calcium levels were within the normal range, while three patients had hyperphosphatemia and one patient had normal phosphate levels. All patients had iPTH levels >1000 pg/ml in the last six months. Before the surgery, all patients had received long-term phosphate-binding drugs, including calcium-based and non-calcium-based drugs and vitamin D3 agonists. All patients underwent total parathyroidectomy with autotransplantation of parathyroid tissue in the right antebrachial regions, except for the second patient who received the transplant in the left antebrachial region due to an AV fistula in the right arm. Conclusion: In dialysis patients, especially in developing countries, approximately 10.7% of them experience SHPT with PTH levels >1,000 pg/mL, and one study in Indonesia showed that around 35% of patients undergoing chronic hemodialysis had PTH levels >200 pg/ml, making parathyroidectomy a highly possible option considering that medications such as cinacalcet are more expensive and not widely available.

#5586 EFFICACY OF ABLATION OF PARATHYROID AUTOGRAFTS FOR RECURRENT HYPERPARATHYROIDISM AFTER TOTAL PARATHYROIDECTOMY AND DELTOID AUTO TRANSPLANTATION

Abstract Background and Aims TPDI is the treatment of choice for patients with severe hyperparathyroidism who have failed medical therapy in our centre. The auto-transplantation of parathyroid tissue in the deltoid reduces the risk of permanent hypoparathyroidism. However, there is a risk of recurrent hyperparathyroidism from the implanted parathyroid tissue. Traditionally, these autografts are removed surgically in the event of recurrent hyperparathyroidism exposing the patients to the risk of permanent hypoparathyroidism. We attempted radiologically guided ablation of the implanted tissue to allow near but not complete ablation of the tissue. We aim to report our experience in using this technique to treat patients with recurrent hyperparathyroidism following TPDI. Method This is a single centre retrospective study of 9 patients who are on regular dialysis and underwent ablation of their deltoid parathyroid implants at Singapore General Hospital between May 2020 to July 2022. Baseline demographic data, as well as biochemistry results including intact parathyroid hormone (iPTH), serum calcium, phosphorus and alkaline phosphatase (ALP) levels were retrieved from electronic medical records and analysed. We define successful procedure as achieving 2 out of the following 3 criteria: i. >50% drop in iPTH level at 3 months, ii. correction of hypercalcemia at 3 months, iii. off calcimimetic at 3 months Results A total of 9 patients underwent ablation of their parathyroid deltoid implants, of which 8 (89%) had thermal ablation and 1 (11%) had cryoablation. 1 patient required a repeat procedure within 3 month as only 50% of the implanted tissue were targeted instead of the intended 80% and another patient had a repeat procedure >3 month after initial unsuccessful procedure. The median age of patients undergoing this procedure was 60 years (IQR 60, 66) and majority were female (5/9, 55.5%). 8 out of 9 patients were on haemodialysis. 7 out of 9 patients (78%) had a successful procedure based on our definition. 6 patients (67%) had a >50% reduction of iPTH at 3 month, 6 patients (67%) were off calcimimetic at 3 months and out of the 5 patients who were hypercalcemic pre procedure, 4(80%) patients had normalisation of hypercalcemia at 3 months. 3 patients (33%) had iPTH < 2x upper limit of normal with only 1 out of the 3 patient requiring high dose oral calcium replacement at 3 months. Pre ablation levels of PTH decreased from 191.87 ± 93.52 pmol/L to 99.77 ± 111.007 pmol/L (P = 0.773) 1 day after ablation and 92.450 ± 70.235 pmol/L (P = .0450) at 1 month and 91.25 ± 81.25 (P = .024) pmol/L at 3 months. Serum calcium levels decreased from 2.48 mmol/L ± 0.286 pre ablation to 2.11 mmol/L ± 0.322 1 day post ablation (P = 0.007) and remained 2.28 mmol/L ± 0.403 (P = .122) at 3 months post ablation. Serum ALP levels decreased from 478 ± 292.00 pre ablation to 238 ± 157 at 3 months post ablation. There were no re-admissions and no immediate post procedure complications in all patients. 4 out of 9 patients (44%) required intravenous calcium replacement post- procedure during the same admission. Limitations of this study are the relatively short follow-up duration and the small number of patients. 2 out of the 9 patients were lost to follow up at 3 months. Conclusion Ablation of deltoid parathyroid autografts may be a safe and effective minimally invasive procedure to manage recurrent hyperparathyroidism and minimising the risk of permanent hypoparathyroidism. However, further studies with larger sample sizes and longer follow up duration would be prudent to confirm our findings

#3724 CHANGES IN CARDIOVASCULAR CALCIFICATION AFTER PARATHYROIDECTOMY IN DIALYSIS-DEPENDENT PATIENTS

Abstract Background and Aims Vascular calcification (VC) is common in patients with end stage kidney disease on dialysis and with secondary hyperparathyroidism (SHPT). There is a lack of knowledge regarding dynamics of VC after surgical treatment of SHPT. We aimed to evaluate evolution of coronary artery calcification (CAC) and abdominal aortic calcification (AAC) after parathyroidectomy (PTx) in dialysis patients with SHPT. Method The prospective cohort study included 33 dialysis-dependent patients (mean age of 50±13 years) with severe SHPT who underwent subtotal (n = 16) or total PTx with autotransplantation of parathyroid tissue (n = 17). Cardiac computed tomography scan (quantification of coronary calcium by Agatston method) and lateral lumbar X-ray (semi-quantitative Kauppila score) were used to assess prevalence of VC before and 18 months after surgery. Levels of serum total calcium, phosphorus, parathyroid hormone (PTH), and alkaline phosphatase (AP) before and 18 months after surgery were also evaluated. Results In our cohort median dialysis vintage before surgery was 71 [Q1-Q3: 29; 136] months, total serum Ca was 2.47±0.23 mmol/l, median PTH was 139 [Q1-Q3: 90; 161] pg/ml. Prevalence of CAC before PTx was 79% (n = 26), and 61% (n = 20) of patients had AAC. Of note, 54.5% of the patients had severe coronary calcification (>400 AU), while only 12% were considered to have severe calcification using Kauppila score (>12). We observed moderate positive correlation between CAC and AAC scores (Spearman's ρ = 0.699 [95% CI: 0.48; 0.84], р<0.0001). Both CAC and AAC scores correlated moderately with age of the patients (ρ = 0.57 [95% CI: 0.3; 0.76], р = 0.0002, and ρ = 0.64 [95% CI: 0.39; 0.8], р<0.0001, respectively), AAC had weak correlation with their dialysis vintage (ρ = 0.45 [95% CI: 0.14; 0.68], р = 0.005. Median of baseline CAC was 458 [Q1-Q3: 23; 1585] AU, after 18 months - 491 [Q1-Q3: 58; 1956] AU, no statistically significant differences were observed (p = 0.91, Wilcoxon test). We did not find statistically significant differences between median of Kauppila scores before and after PTx as well: 3 [Q1-Q3: 0; 10] and 2 [Q1-Q3: 0; 10], correspondingly, p = 0.17 (Wilcoxon test) – Fig. 1. As it can be seen from Fig. 1, dynamics of both CAC and AAC values before and after PTx varied markedly across subjects. To investigate the factors that can promote VC we divided patients into 2 groups based on dynamics of САС (as the most accurate assessment method) 18 months after surgery: group 1 with CAC progression of more than 50 AU (n = 9) and group 2 with regression or progression less than 50 AU (n = 24). Patients who had progression of coronary calcification by the end of the follow-up had higher age (59±11 vs 46±12 years in 2nd group, p = 0.0128) higher serum calcium levels (2.57±0.24 vs 2.29±0.32 mmol/l in 2nd group, p = 0.0267), and higher AP levels at follow-up (69.8 [Q1-Q3: 62.8, 96.0] vs 51.7 [Q1-Q3: 41.4; 57.1] U/ml in 2nd group, p = 0.003). Univariate analysis showed no significant differences between groups comparing dialysis vintage (p = 0.53), phosphate levels (p = 0.54), PTH levels (p = 0.32). In addition, CAC progression risk was not associated with type of surgery (total vs subtotal PTx RR = 1.11 [95% CI: 0.71; 1.8], OR = 1.48 [95% CI: 0.3; 5.7], p = 0.708). Conclusion Prevalence of vascular calcification in dialysis-dependent patients with severe SHPT is high. Progression of CAC by 18 months after PTx was associated with higher age of the patients, higher follow-up levels of serum total Ca and AP.

Autotransplantation of parathyroid tissue into subcutaneous subclavicular area following total parathyroidectomy in secondary hyperparathyroidism.

Total parathyroidectomy with autotransplantation is still an excellent treatment option for secondary hyperparathyroidism. Intramuscular or subcutaneous parathyroid autotransplantation has been previously reported; however, there have been no studies to date regarding the implantation of the parathyroid tissue in the subclavian area of the neck. This was a prospective cross-sectional study between 2018 and 2019. Patients who underwent total parathyroidectomy with autotransplantation of parathyroid tissue into subcutaneous subclavicular area due to secondary hyperparathyroidism were included. The patients' demographic information, including age and gender, was gathered, and the length of the dialysis period was asked from the patients. To evaluate the outcome of the study, parathyroid hormone (PTH) was measured and recorded before and after the operation. SPSS software, version 26, was used for data analysis. Forty-two patients with a mean age of 41.05 ± 9.41years were included. The mean length of the dialysis period was 8.07 ± 2.68years. The mean primary PTH was 1770.61 ± 482.97pg/ml (range: 656-2500 <). After 6weeks of operation, 19 patients (45.2%) had functional autotransplanted tissue, and the median PTH was 28pg/ml (IQR: 33.55, range: 0.1-221.8). However, the results showed that after 10weeks, the patients with functional tissue were increased to 22 (52.4%), and the median PTH was 35pg/ml (IQR: 48, range: 5.0-602.9). The functionality of autotransplanted tissue in the 6th and 10th weeks after surgery had no significant association with age, gender, and length of the dialysis period (pvalue > 0.05). Subcutaneous implantation is recommended in the treatment of secondary hyperparathyroidism based on its high success rate and ease of use, suitable vascularization, easy accessibility to the surgery location in case of the need for autographtectomy.

MO815: Cinacalcet Does not Prevent Severe Hypocalcemia After Parathyroidectomy in Dialysis-Dependent Patients

Abstract BACKGROUND AND AIMS Surgical treatment of secondary hyperparathyroidism (SHPT) is often followed by the rapid development of hypocalcemia, which is also known as hungry bone syndrome. We aimed to evaluate if preoperative use of cinacalcet may help to prevent severe hypocalcemia after parathyroidectomy (PTx) for SHPT in dialysis-dependent patients during the early postoperative period. METHOD The retrospective analysis included 616 patients who underwent PTx (either subtotal or total PTx with autotransplantation of parathyroid tissue) for SHPT between 2011 and 2019 in the single tertiary care center of endocrine surgery. Data on severe hypocalcemia development were available for 559 of the patients, 172 of them received cinacalcet before surgery. The median age of the patients was 49 (IQR 40–56) years and the median dialysis duration was 94 (IQR 56–142) months. Preoperative parathyroid hormone level was 153 pmol/L (IQR 105–223), total serum Ca was 2.44 mmol/L (IQR 2.24–2.61) and alkaline phosphatase was 283 IU/l (IQR 157–645). Severe postoperative hypocalcemia was defined as a serum ionized Ca level &amp;lt;0.9 mmol/L on the second or third day post-PTx. We also assessed need for intravenous (IV) calcium supplementation and the duration of in-hospital stay (≤7 days or &amp;gt;7 days) as surrogate markers of hungry bone syndrome severity. RESULTS Among patients treated with cinacalcet, 55.8% (n = 96) received 30 mg/day, 33.1% (n = 57)received 60 mg/day, 10.5% (n = 18) received 90 mg/day and 0.6% (n = 1) received 120 mg/day. Prevalence of severe hypocalcemia was less in patients who received 90 or more mg of cinacalcet a day, although this difference did not reach statistical significance (P = .1038) (Figure 1A). Use of cinacalcet (yes/no) was not associated with the risk of severe postoperative hypocalcemia: RR = 1.047 [95% confidence interval (95% CI) 0.946–1.146], OR = 1.229 (95% CI 0.801–1.886), P = .3837. A total of 54% of the patients were administered with IV calcium. Preoperative use of cinacalcet did not reduce the risk of IV calcium supplementation need: RR = 0.93 (95% CI 0.79–1.09), OR = 0.86 (95% CI 0.61–1.21); P = .3749. Among patients supplemented with IV calcium, medians of total Ca amount did not differ between those who received pre-PTx cinacalcet and those who did not: 6 (IQR 3–15) g versus 6 (IQR 4–10) g, respectively, P = .3981. Patients who received 60 mg of cinacalcet a day or more were more likely to require higher amounts of total IV Ca (Figure 1B), but this was not statistically significant [RR = 1.4 (95% CI 0.83–2.4); P = .2138]. In terms of length of hospital stay, we did not find differences between patients received 30, 60 and ≥ 90 mg of cinacalcet a day (P = .1285) (Figure 1C). Use of cinacalcet was not associated with prolonged (&amp;gt;7 days) in-hospital stay: RR = 0.863 (95% CI 0.708–1.04), OR = 0.765 (95% CI 0.546–1.081); P = .1417. CONCLUSION We found no evidence of a protective effect of preoperative cinacalcet use, neither on the prevalence nor on the severity of hypocalcemia development after PTx for SHPT in dialysis patients.

MO816: Bone Turnover Markers as Risk Factors of Severe Hypocalcemia After Parathyroidectomy for Secondary Hyperparathyroidism

Abstract BACKGROUND AND AIMS Hungry bone syndrome is a common postoperative complication after parathyroidectomy (PTx) for severe secondary hyperparathyroidism (SHPT). We aimed to evaluate whether preoperative levels of serum alkaline phosphatase (AP) and β-crosslaps (CTX) are associated with the development of severe hypocalcemia after PTx for SHPT in dialysis-dependent patients. METHOD The retrospective study included 127 severe SHPT dialysis-dependent patients who underwent subtotal (SPTx) or total parathyroidectomy with autotransplantation of parathyroid tissue (PTx + AT) in a single high-volume centre of endocrine surgery between 2011 and 2014. Severe postoperative hypocalcemia was defined as an ionized serum calcium level &amp;lt;0.9 mmol/L on a day 3 after surgery. RESULTS Severe hypocalcemia was observed in 83 (65.4%) patients after PTx. Comparing to those with mild hypocalcemia, hypoCa patients were significantly younger (mean age 44.2 ± 11.3 years versus 49.7 ± 10.4 years in a non-hypoCa group; P = .0089). Patients in two groups did not differ in terms of gender (P = .198), dialysis vintage (P = .24) and type of surgery (TPTx + AT or SPTx; P = .127). Preoperative PTH level was significantly higher in hypoCa group comparing to non-hypo Ca group [134 (Q1–Q3: 103–190) pmol/L versus 93.9 (Q1–Q3: 74.6–124.3) pmol/L, respectively; P &amp;lt; .0001]. In univariate analysis preoperative AP level was associated with the risk of postoperative severe hypocalcemia [363.2 (Q1–Q3: 180.9–726.3) IU in hypoCa group versus 142.1 (Q1–Q3: 97.2–223.7) IU in non-hypoCa group; P &amp;lt; 0.0001) (Figure 1). AP level above the cut-off value of 238.5 IU/L caused a 5-fold increase risk of severe hypocalcemia. We observed a moderate negative correlation between preoperative AP level and serum ionized calcium level on the third postoperative day after PTx {ρ = –0.637 [95% confidence interval (95% CI) –0.51 to –0.74]; P &amp;lt; .0001}. In contrast, preoperative CTX level was not associated with postoperative severe hypocalcemia [5.34 (Q1–Q3: 4.06–6.03) µg/L in hypoCa group versus 4.6 (Q1–Q3: 3.42–5.69) µg/L in non-hypoCa group; P = .191] (Figure 2). Moreover, the correlation between preoperative AP and CTX levels was weak, even though it was statistically significant [ρ = 0.27 (95% CI 0.08–0.44); P = .006]; and we observed no statistically significant correlation between preoperative CTX and PTH levels (P = .07). The multivariate logistic regression revealed AP level as the only independent risk factor of severe hypocalcemia development after PTx [ОR 1.006 (95% CI 1.002–1.009) per each IU; P = .005]. CONCLUSION We identified serum AP level, but not CTX, as an independent risk factor of severe hypocalcemia development after surgical treatment of SHPT. The correlation between CTX and other bone turnover markers (PTH, AP) is weak in dialysis-dependent patients with severe SHPT.

MO812: Risk Factors of Long-Term Hypocalcemia After Parathyroidectomy in Dialysis-Dependent Patients

Abstract BACKGROUND AND AIMS Surgical treatment of secondary hyperparathyroidism (SHPT) is often followed by long-term hypocalcemia, also known as a hungry bone syndrome. We aimed to evaluate the prevalence and risk factors of prolonged hypocalcemia after parathyroidectomy (PTx) for SHPT in dialysis-dependent patients. METHOD The retrospective study included 1711 analyses for total serum calcium (Ca) obtained from 372 patients who underwent PTx (either subtotal or total PTx with autotransplantation of parathyroid tissue) for SHPT between 2011 and 2019 in a tertiary care centre of endocrine surgery. The median age of the patients was 50 (IQR 40–57) years, and the median dialysis duration was 82 (IQR 48–134) months. Preoperative parathyroid hormone level was 136 pmol/L (IQR 99.4–210.4), total serum Ca was 2.43 mmol/L (IQR 2.26–2.57) and alkaline phosphatase (AP) was 183 IU/L (IQR 129–395). Follow-up period after surgery ranged from 3 months to 6 years. Postoperative hypocalcemia was defined as a total serum Ca level &amp;lt;2.1 mmol/L, severe hypocalcemia—&amp;lt;1.9 mmol/L. To identify possible risk factors, we took total serum Ca level &amp;lt;2.1 mmol/L after 12 months from PTx as the endpoint. RESULTS Hypocalcemia was registered at least once in 81.5% (n = 303), severe hypocalcemiain 59.1% (n = 224) of the patients in the postoperative period. The prevalence of hypocalcemia and severe hypocalcemia gradually decreased from 3 to 24 months post-PTx and remained relatively stable thereafter (Figure 1). The fraction of patients with moderate hypocalcemia (total serum Ca 1.9–2.1 mmol/L) varied from 17% to 41% during 3–60 months of follow-up. Twelve months after surgery, 53.2% (150 of 282) of the patients had a total Ca level &amp;lt;2.1 mmol/L. Univariate analysis showed no association of hypocalcemia with age (P = .997), sex (P = .17), dialysis vintage (P = .32), modality of treatment (HD/PD, P = .74), type of surgery (P = .29) or use of calcimimetics before surgery (P = .89). Pre-operative parathyroid hormone (P = .55), total Ca (P = .089) and β-crosslaps (P = .69) levels were not associated with an increased risk of hypocalcemia as well. However, low preoperative (P = .037) and postoperative (P = .0092) ionized Ca and high preoperative AP (P = 0.014) levels were associated with an increased risk of long-term postoperative hypocalcemia. Multivariate analysis discovered postoperative ionized Ca as the only independent predictor of prolonged postoperative hypocalcemia [OR = 0.022 (95% confidence interval 0.001–0.356); P = 0.007]. CONCLUSION We identified a high prevalence of moderate and severe hypocalcemia in the long-term period after PTx in dialysis-dependent patients. Total serum Ca levels return to a normal range at 24 months post-PTx in approximately half of the patients. Patients with low preoperative and postoperative serum ionized Ca and high preoperative AP levels are more likely to have persistent hungry bone syndrome after PTx. Immediate postoperative ionized calcium level is the only independent predictor of long-term hypocalcemia after PTx for SHPT.

The Importance of Cryopreserved Parathyroid Tissue Autotransplantation in the Hypoparathyroidism Treatment after Secondary Hyperparathyroidism Surgery

The Importance of Cryopreserved Parathyroid Tissue Autotransplantation in the Hypoparathyroidism Treatment after Secondary Hyperparathyroidism Surgery

Secondary hyperparathyroidism: recurrence after total parathyroidectomy with autotransplantation.

Secondary hyperparathyroidism (sHPTH) is common in patients with end-stage chronic kidney disease. If drug therapy fails, total parathyroidectomy with autotransplantation of parathyroid tissue into the forearm (PTX-AT) is the most widely used procedure. High recurrence rates of sHPTH following PTX-AT are reported in the literature. The aim of this study was to evaluate recurrences of sHPTH following PTX-AT in detail in order to develop strategies to prevent recurrences in the future. This retrospective study analysed a single-centre cohort of 42 patients who underwent PTX-AT for sHPTH at a tertiary centre in Switzerland. Postoperative PTH levels were evaluated to determine the recurrence and persistence rates and the time to recurrence. Furthermore, the peri- and postoperative outcomes were assessed. Patients on dialysis and patients with a functioning kidney transplant suffering tertiary HPTH were analysed separately. Intraoperative measurements showed that serum PTH decreased to 6.9% (3.3&ndash;15.0%) of the preoperative baseline level. After a median follow-up of 89.5 months (IQR 31.9&ndash;152.9), persistence of sHPTH was found in five patients (11.9%) and recurrence in four patients (9.5%), giving a total recurrence rate of 21.4%. Recurrence of sHPTH after PTX remains a problem, occurring in every fifth patient. In our experience, the introduction of intraoperative PTH measurement has helped to lower the rates of persistence and recurrence. Further reductions in the recurrence rate might be achieved with novel, more accurate pre- and intraoperative imaging techniques.

Fatal Hypocalcaemia Due to Hungry Bone Syndrome with Secondary Refractory HyperParathyroidism after Parathyroidectomy: A Case Report

IntroductionHungry bone syndrome (HBS) refers to the rapid, profound, and prolonged hypocalcaemia associated with hypophosphatemia and hypomagnesaemia, and is exacerbated by suppressed parathyroid hormone (PTH) levels, which follows parathyroidectomy in patients with severe primary hyperparathyroidism (PHPT) and preoperative high bone turnover. [1]Case reportThis report concerns a dialysed patient who underwent surgical treatment for secondary refractory hyperparathyroidism. Haemodialysis was carried out pre-operatively, and subsequently, a total parathyroidectomy with auto-transplantation of parathyroid tissue in the sternocleidomastoid muscle (SCM) was performed. Rapid and progressive hypocalcaemia symptoms developed during the second day postoperatively. Acute cardiac symptoms with tachyarrhythmia, haemodynamic instability and finally asystole occurred, which required cardiopulmonary resuscitation (CPR). The ionic calcium level was 2.2 mg/dL being consistent with a diagnosis of HBS. A second cardiac arrest unresponsive to CPR followed an initial period of normal sinus rhythm. Death ensued shortly after. Before death, the ionic calcium was 3.1 mg/dL.ConclusionHBS, after parathyroidectomy in patients with secondary hyperparathyroidism (SHPT), may be severe, prolonged and sometimes fatal. Generally, HBS symptomatology is that of a mild hypocalcaemia. It can, however, include heart rhythm disturbances with haemodynamic alterations requiring intensive care measurements and even cardiopulmonary resuscitation. A close clinical and laboratory post-parathyroidectomy monitoring of dialysed patients is of the utmost importance.

Parathyroid carcinoma arising from auto-transplanted parathyroid tissue after Total Parathyroidectomy in chronic kidney disease patient: a case report

BackgroundSecondary hyperparathyroidism is a common complication in patients with chronic kidney disease that requires vigilant treatment due to its high mortality rate. Pharmacologic therapy is recommended as an initial treatment; if there is no response, a total parathyroidectomy is performed. In some cases, surgery is accompanied by auto-transplantation of parathyroid tissue.Case presentationThe patient was diagnosed with chronic kidney disease and received a kidney transplant. However, due to rejection of the transplanted kidney, medical nephrectomy was carried out and routine hemodialysis was initiated and observed. At this time, secondary hyperparathyroidism with elevated parathyroid hormone and hyperphosphatemia developed and pharmacologic treatment was applied. However, there was no response to pharmacologic treatment; therefore, total parathyroidectomy with auto-transplantation was performed. Eight years after surgery, a growing mass was observed in the transplantation site, accompanied by an elevation of parathyroid hormone. A complete resection of the mass was performed, and the patient was diagnosed with parathyroid carcinoma. Additional adjuvant radiation therapy was ordered, and the patient is being monitored.ConclusionsThis is a rare but remarkable case of parathyroid carcinoma arising from auto-transplanted parathyroid tissue after total parathyroidectomy in a patient with secondary hyperparathyroidism. We suggest caution should be taken when choosing to auto- transplant parathyroid tissue and that careful postoperative observation should be performed.

Parathyroid Tissue Cryopreservation: Does the Storage Time Affect Viability and Functionality?

Parathyroidectomy is a standard practice to treat recurrent or persistent hyperparathyroidism. However, this can lead to the onset of hypoparathyroidism, treatable with the autotransplantation of parathyroid tissue (PT). Tissue can be transplanted immediately after parathyroidectomy or cryopreserved and transplanted only in case of necessity. Since 2011, the Cord Blood Bank and Cardiovascular Tissue Bank of Emilia-Romagna has been storing PT for potential autologous transplantation. To date, there are highly variable data about the viability and function of PT after thawing. However, it is not clear if the PT quality is affected by different cryopreservation protocols and/or by the storage time. The aim of this study was to assess the ex vivo function and viability of the PTs of ten patients stored in the Bank. Tissue morphology was evaluated before and after cryopreservation through histological investigations. PT function was analyzed by assessing the ability of cryopreserved PT to synthesize and secrete parathyroid hormone (PTH) in response to different calcium concentrations. Moreover, viability and function were also investigated on tissue-isolated cells in culture. These data show that tested tissues appear to be viable and able to produce PTH even after 5 years of storage, and the histological architecture is well preserved.

SUN-492 Unresolved Hyperparathyroidism Due To Mediastinal Parathyroid Adenoma

Background: Mediastinal parathyroid adenomas are found in approximately 1-2% of patients undergoing workup and surgery for primary hyperparathyroidism, although the actual incidence of mediastinal parathyroid glands is higher in autopsy series. Preoperative planning is crucial for optimal intraoperative success. Clinical case: A 75 years-old woman presented with persistent hyperparathyroidism despite prior neck explorations and parathyroidectomy in the 1990s where she had 2 parathyroid glands removed. This was in the era before routine localization studies were performed. Over the decades since, her calcium level peaked at 12 mg/dL, and parathyroid hormone (PTH) levels ranged in the 300-500s pg/mL, but calcium had been able to be kept to less than 11 mg/dL with medical management. Over the past 5 years, she developed worsening renal insufficiency and osteopenia necessitating discussion of reoperation. Neck ultrasound did not identify a parathyroid adenoma. Sestamibi parathyroid scan localized a parathyroid adenoma to the upper mediastinum. CT scan showed a 2 cm substernal mass in the anterior mediastinum slightly below the brachiocephalic vein. Laryngoscopy showed a non-functional right vocal cord consistent with prior right recurrent laryngeal nerve injury. After extensive preoperative counseling of the risks and benefits, including the possible need for hemi-sternotomy, the patient wanted to proceed with reoperation. She underwent attempted transcervical approach to reach the parathyroid adenoma, but the adenoma was beyond reach, and thus a hemi-sternotomy was performed allowing for parathyroidectomy with removal of a 2.5 cm x 1.7 cm adenoma. Given the possibility that the only remaining parathyroid tissue was her ectopic parathyroid adenoma, a portion of the parathyroid adenoma was also autotransplanted onto her abdominal wall subcutaneous tissue. PTH levels decreased from 571 pg/mL to 66 pg/mL. Pathology confirmed hypercellular parathyroid tissue. She initially became hypocalcemic postoperatively but normalized with oral calcium and recovered well. Conclusion: Preoperative imaging is critical in the reoperation for persistent hyperparathyroidism since an ectopic parathyroid is a possible cause. Preoperative planning is essential for a safe and effective reoperation, especially for a mediastinal parathyroid adenoma. Autotransplantation of parathyroid tissue after reoperative parathyroidectomy should be considered to prevent severe hypoparathyroidism if the status of any remaining gland is uncertain after prior parathyroidectomy attempts.

Total Parathyroidectomy with Subcutaneous Parathyroid Forearm Autotransplantation in the Treatment of Secondary Hyperparathyroidism: A Single-Center Experience.

Introduction Secondary hyperparathyroidism is common in chronic kidney disease. Parathyroidectomy is indicated in refractory hyperparathyroidism when medical treatments and so the parathyroid hormone levels cannot be lowered to acceptable values without causing significant hyperphosphatemia or hypercalcemia. The aim of this study is to compare the efficacy and safety of total parathyroidectomy with subcutaneous forearm autotransplantation with total parathyroidectomy with intramuscular forearm autotransplantation. Materials and Methods A single-center retrospective cohort study of total parathyroidectomy with forearm autotransplantation from January 2002 to February 2013 was performed. According to the surgical technique, patients were divided into an intramuscular group (Group 1) and a subcutaneous group (Group 2). 38 patients with secondary hyperparathyroidism were enrolled; 23 patients were subjected to total parathyroidectomy with parathyroid tissue replanting in the subcutaneous forearm of the upper nondominant limb, while 15 patients were subjected to replanting in the intramuscular seat. Results A total of 38 patients (56 ± 13 years) were enrolled. In both groups, the preoperative iPTH value was markedly high, 1750 ± 619 pg/ml in the intramuscular autotransplantation group and 1527 ± 451 pg/ml in the subcutaneous autotransplantation group (p = 0.079). Transient hypoparathyroidism was shown in 7 patients, and 1 patient showed persistent hypoparathyroidism (p = 0.387). 2 patients showed persistent hyperparathyroidism (p = 0.816), and in 2 others was found recurrent hyperparathyroidism (p = 0.816); 3 of them underwent autograftectomy. The anterior compartment of the forearm nondominant limb was sacrificed in 1 case of intramuscular autotransplantation with functional arm deficit. Conclusions The efficacy and safety of parathyroid tissue autotransplantation in the subcutaneous forearm of the upper nondominant limb is confirmed with a good rate of tissue engraftment and with a comparable number of postsurgical transient and persistent hypoparathyroidism and hyperparathyroidism incidence in both techniques. Furthermore, this technique preserves arm functionality in the case of autograftectomy. Consequently, it is our opinion that total parathyroidectomy with subcutaneous forearm autotransplantation is currently the best choice.

Management and outcomes of hyperparathyroidism: a case series from a single institution over two decades.

BackgroundHyperparathyroidism is a frequent endocrine disorder with variable clinical manifestations and outcomes. We aimed to evaluate clinical presentations, management and outcomes of hyperparathyroidism.MethodsA retrospective study was conducted to include all patients presented with hyperparathyroidism between 1995 and 2014 at a single tertiary hospital with an average follow-up period of 46 months. Data were reviewed for clinical presentations, diagnostic work-up, intraoperative findings, management, and outcomes.ResultWe identified 161 patients with hyperparathyroidism; 69% were females and the mean age was 49.4±15 years. Patients presented mainly with musculoskeletal (65.8%), renal (37.3%), gastrointestinal tract (53.8%) and neuropsychiatric (8.8%) manifestations. At presentation, mean serum calcium and parathyroid hormone levels were elevated while mean vitamin D level was lower. Sestamibi-99mTc (MIBI) scintigraphy was done for 134 patients (83.2%) and was positive in 94 (70%). Primary hyperparathyroidism (67.7%) was the most frequent diagnosis followed by secondary (29.8%) and tertiary hyperparathyroidism (2.5%). The frequent indication for surgery was hypercalcemia (67.3%), bone disease (35.6%) and renal calculi (28.9%). The main postoperative pathology was parathyroid adenoma (63.1%) followed by hyperplasia (37.3%). Fourteen (8.9%) and 18 (11.4%) patients had persistent and recurrent hyperparathyroidism, respectively. Autotransplantation of parathyroid tissue was done in 36 cases.ConclusionPrimary hyperparathyroidism is the most frequent cause of the parathyroid disease. Parathyroidectomy is the effective surgical approach in symptomatic patients. Further studies are needed to establish the association between vitamin D levels, renal disorders and persistent or recurrent hyperparathyroidism.

Parathyroid transplantation in thyroid surgery.

Permanent hypoparathyroidism following thyroid surgery is rare. Its prevalence is reported to be below 1-2% if surgery is performed by experienced thyroid surgeons. Parathyroid identification and preservation in situ with good vascular supply is the mainstay of safe thyroid surgery. However, if the parathyroid glands are damaged, autotransplantation should be undertaken to preserve their function. Parathyroid transplantation can be considered in three distinct modes of application: (I) fresh parathyroid tissue autotransplantation during thyroidectomy in order to reduce the risk of permanent hypoparathyroidism; (II) cryopreserved parathyroid tissue autotransplantation in patients with permanent hypoparathyroidism; (III) parathyroid allotransplantation in patients with permanent hypoparathyroidism when cryopreserved parathyroid tissue is not available for grafting. Nowadays, allotransplantation of cultured parathyroid cells without immunosuppression should be taken into consideration in selected patients as an alternative to calcium and vitamin D3 supplementation in management of permanent hypoparathyroidism. This paper is aimed to provide a review of current status of various parathyroid transplantation techniques in thyroid surgery.

Autotransplantation of parathyroid grafts into the tibialis anterior muscle after parathyroidectomy: a novel autotransplantation site.

BackgroundSurgical management of renal secondary hyperparathyroidism (sHPT) is varying. Total parathyroidectomy with heterotopic autotransplantation (TPTX + AT) is one of the standard surgical procedures in sHPT, but there is no consensus about the optimal site for graft insertion. At the surgical department of the University Hospital of Heidelberg we prefer the autotransplantation into the tibialis anterior muscle. The aim of this study was to assess the long-term function of the auto-transplanted parathyroid tissue in this type of surgical procedure.MethodsThe function of the autograft of 42 patients was assessed 8.2 ± 2.5 years after surgery, using a modified Casanova-test of the leg bearing the parathyroid tissue. Ischemic blockage was induced by tourniquet and the levels of parathyroid hormone (PTH) were assessed during the test.ResultsAt the point of assessment, the ischemic blockage led to a significant reduction in the concentration of PTH (≥50 % of the baseline value) in 19 patients (45 %) indicating well-functioning autografts. In 11 patients (26 %), ischemic blockage did not cause any change in the concentration of PTH (≤20 % of the baseline value), indicating functioning residual parathyroid tissue from another site. The source of PTH production was classified as unidentifiable in five patients (12 %). Two patients had developed graft-dependent recurrent HPT (5 %) without therapeutic consequences and three patients suffered from persistent symptomatic hypoparathyroidism (7 %).ConclusionsThese results indicate that TPTX + AT into the tibialis anterior muscle is a successful surgical treatment for renal HPT and that the modified Casanova-test is a suitable diagnostic tool for autografts function.

Severe neonatal hypercalcemia in 4-month-old, presented with respiratory distress and chest wall deformity

Neonatal severe hyperparathyroidism (NSHPT) is a rare disease affecting calcium metabolism and results in severe life-treating hypocalcemia of the neonates. Diagnosis can be challenging due to variable and nonspecific symptomatology. We are reporting on a 4-month-old female infant presenting with respiratory distress and chest wall deformity. We are trying to highlight different surgical options for this rare disease and importance of close collaboration with the pediatric endocrinologist in the treatment plan for those patients. • We point out different surgical options for neonatal severe hyperparathyroidism. • Total parathyroidectomy remains the most effective longterm treatment for neonatal severe hyperparathyroidism. • To reduce the long-term calcium supplementations, parathyroid tissue autotransplantation is needed.

Development of hypoparathyroidism animal model and the feasibility of small intestinal submucosa application on the parathyroid autotransplantation.

The purpose of this study is to evaluate the feasibility of small intestinal submucosa (SIS) application on the parathyroid autotransplantation in a rat model of hypoparathyroidism. The rats were divided into four groups: NC (no procedure, n = 5), PTX (total parathyroidectomy, n = 6), PT (total parathyroidectomy and parathyroid autotransplantation, n = 10) and PT + SIS group (total parathyroidectomy and parathyroid autotransplantation with SIS, n = 10). The levels of parathyroid hormone (PTH), calcium, and phosphorous were measured on 0, 3, 7, 21, 56 and 84 days after surgery. PTH level was expressed as median (interquartile range) and histological and immunohistochemical examinations were performed. PTH levels were significantly decreased to "not detectable level" from day 3 in PTX group. PTH was not detected in both PT and PT + SIS groups on the 21st day. On the 56th day, PTH levels were increased in both groups: 3 out of 8 rats (37.5%) in the PT group, 6 out of 9 rats (66.7%) in the PT + SIS group. The PTH level was fully recovered to its preoperative range on the day 84 as 6 of 8 rats (75%) of the PT group and 7 of 9 rats (77.8%) of the PT + SIS group were recovered; the PTH levels were 117.84 and 178.36 pg/ml, respectively. The neo-vascularization was well observed around the parathyroid tissue, and the number of new vessels formed was higher in the PT + SIS group (15 vessels/high power field) as compared to the PT group (10 vessels/high power field). This study showed the feasibility and the treatment effect of SIS as the success rate of autotransplantation of parathyroid tissue was significantly increased without severe inflammatory response in hypothyroidism animal model.