Incremento de la densidad mineral ósea en pacientes con hiperparatiroidismo terciario tras paratiroidectomía total y autotrasplante de glándula paratiroides

IntroductionChanges in bone metabolism and bone mineral density are observed in renal transplant patients with tertiary hyperparathyroidism. The objective of this work was to analyse the increase in bone mineral density, as well the laboratory results, after total parathyroidectomy and autotransplantation in renal transplant patients with tertiary hyperparathyroidism.Material and methodsA retrospective study was conducted in which the bone mineral density values at femoral and lumbar level were analysed, together with the serum levels of calcium, phosphorous, parathyroid hormone (PTH), and alkaline phosphatase in 13 renal transplant patients with tertiary hyperparathyroidism before and after total parathyroidectomy and autotransplantation of the parathyroid glands.ResultsParathyroidectomy is associated with an increase in bone mineral density at femoral and lumbar level, with an increase of 8.6 ± 6.7% at lumbar level, and 4 ± 16.1% at femoral level. The decrease in calcium after the parathyroidectomy was 2.8 mg/dL (95% CI; 1.9-4). The decrease in PTH was 172 pg/mL (95% CI; 98-354) and the decrease in alkaline phosphatase was 229 U/L (95% CI; 70-371).ConclusionsTotal parathyroidectomy and autotransplantation of the parathyroid glands in renal transplant patients with tertiary hyperparathyroidism increases the bone mineral density. Furthermore, the calcium, PTH and alkaline phosphatase returned to normal in the long-term.     

Parathyroid autotransplantation

7 patients with diffuse parathyroid hyperplasia underwent total parathyroidectomy and microsurgical autotransplantation for diffuse parathyroid hyperplasia. 5 of 7 patients showed good function of the grafted parathyroid tissue, as checked by the separate PTH assay from the grafted versus not grafted forearm. In 1 patient parathyroid stimulation test with EDTA infusion and suppression test with calcium infusion were also performed.     

Total Parathyroidectomy Without Autotransplantation for Renal Hyperparathyroidism: Experience with a qPTH-controlled Protocol

Background Controversy regarding the optimal surgical treatment for secondary hyperparathyroidism (sHPT) continues. Subtotal parathyroidectomy (PTX) with a small remnant and total parathyroidectomy with autotransplantation prevail, although impaired by considerable recurrence rates. Concerns about postoperative management and long-term supplementation prevent broader acceptance of total parathyroidectomy without autotransplantation. Materials and Methods The standardized surgical procedure with intraoperative PTH assessment (qPTH) included cervical thymectomy, histological proof of four parathyroid specimens and obligatory cryopreservation of parathyroid tissue in all 23 patients undergoing total PTX without autotransplantation. Whenever qPTH did not normalize, complete cervical exploration of ectopic sites was performed. Another 64 patients with subtotal PTX for sHPT served as comparison for the postoperative course. Results There were 13 primary and 10 completion (5 persistent, 5 recurrent sHPT) total PTX with 14 concurrent thyroid resections performed. Mean preoperative PTH was 1.351 pg/ml (12–72 pg/ml) and serum calcium was 2.5 mmol/l (2.25–2.5 mmol/l). PTH showed intraoperative normalization in 15 patients and a 50% PTH reduction from preoperative values in all. Postoperative course was not significantly different from the subtotal PTX group and showed PTH within the normal range for 5 patients (4 < 35 pg/ml), 7 with PTH < 12 pg/ml, and 4 without measurable PTH. In 4 patients PTH did not normalize postoperatively. Serum calcium levels were below normal in all patients: < 2.25 mmol/l in 9, < 2.00 mmol/l in 7, and <1.8 mmol/l in 6 patients. Only 1 patient required intermittent early postoperative i.v. calcium supplementation, 6 patients received oral calcium and vitamin D supplement for low calcium levels, but no severe hypocalcemic symptoms were encountered. Mean postoperative hospital stay was 5 days. No recurrent laryngeal nerve palsies were encountered. Complications were two cervical bleedings following postoperative hemodialysis requiring evacuation. Conclusions Total PTX without autotransplantation proves to be an equally safe and successful procedure for sHPT as subtotal PTX or total PTX with autotransplantation. Measurable PTH after total PTX as demonstrated in this study, supports the idea of uncontrollable isolated cell nests that are inevitably prone to stimulated growth with time. Therefore, total PTX is superior with regard to prevention of recurrence. Adequate supplementation with calcium and vitamin D, often necessary after subtotal PTX to suppress inadequate PTH and protect from recurrence, will prevent severe hypocalcemia and with the modern aluminium-diminishing dialysis regimen, development of adynamic bone disease appears less likely than feared. If necessary, cryopreserved parathyroid tissue can be autotransplanted on demand.     

Calcium supplement necessary to correct hypocalcemia after total parathyroidectomy for renal osteodystrophy

BACKGROUND: Prediction of the extent of calcium supplement will facilitate safe and efficient management of hypocalcemia in the early postoperative stage of total parathyroidectomy with autotransplantation (PTXa) in patients with renal osteodystrophy. METHODS: The correlation between the extent of calcium deficiency, estimated by the amount of calcium supplement over 48 h after PTXa and using various parameters such as carboxy terminal parathyroid hormone (c-PTH), intact PTH (i-PTH), alkaline phosphatase (ALP), serum calcium, serum phosphorus, duration of hemodialysis, total weight of resected parathyroid glands and degree of subperiosteal resorption of the middle phalanx was examined in 49 patients who underwent PTX with subcutaneous autotransplantation. Bone mineral density (BMD) was also determined before, 3 months and 1 year after PTXa with dual energy X-ray absorptiometry (DEXA) in 13 patients. RESULTS: There was a positive correlation between pre-operative i-PTH level (r=0.56, P<0.0005) or ALP level (r=0.50, P<0.0005) and the amount of calcium supplement over 48 h after PTXa in these patients. Furthermore, the degree of subperiosteal resorption, determined by Jensen's classification, was significantly correlated with the amount of calcium supplement after PTX (P<0.05). Bone mineral density 3 months after (P<0.0005) and 1 year after PTXa (P<0.001) significantly increased compared with BMD before PTXa in all patients examined. CONCLUSION: These findings suggest that the pre-operative determination of i-PTH, ALP levels and degree of subperiosteal resorption allow the management of hypocalcemia safely and efficiently in renal osteodystrophy patients after PTXa.     

Applicability of intraoperative parathyroid hormone assay during thyroidectomy

OBJECTIVE: To evaluate the applicability of intraoperative parathyroid hormone (quick PTH) assay to monitor parathyroid function and to identify clinically significant hypocalcemia compared with postoperative serum calcium monitoring. SUMMARY BACKGROUND DATA: Close monitoring of serum calcium levels is a standard of care to identify post-thyroidectomy hypocalcemia due to parathyroid insufficiency. METHODS: Quick PTH assay was performed before and after thyroidectomy for 100 patients at risk of postoperative hypocalcemia and 20 control patients who underwent unilateral lobectomy. Postoperative serum calcium levels were closely monitored. RESULTS: Control patients had a normal but 38.9 +/- 5.9% (mean +/- SEM) decline in quick PTH after thyroidectomy. Eleven of 100 at-risk patients (11%) developed postoperative hypocalcemia. Hypocalcemic patients had significantly lower quick PTH values after thyroidectomy compared with that of normocalcemic patients. Serum calcium was significantly lower in hypocalcemic patients the morning after operation but not early after the operation (within 6 hours). A normal or less than 75% decline in quick PTH after thyroidectomy can accurately identify normocalcemic patients during surgery as compared to more than 24 hours by serum calcium monitoring. CONCLUSIONS: The quick PTH assay can monitor parathyroid function during thyroidectomy and identify patients at risk of clinically significant hypocalcemia much earlier than serum calcium monitoring. It may facilitate early discharge and the use of parathyroid autotransplantation during thyroidectomy.     

Effect of rate of calcium reduction and a hypocalcemic clamp on parathyroid hormone secretion: a study in dogs

BACKGROUND: The parathyroid hormone (PTH) calcium curve is used to evaluate parathyroid function in clinical studies. However, unanswered questions remain about whether PTH secretion is affected by the rate of calcium reduction and how the maximal PTH response to hypocalcemia is best determined. We performed studies in normal dogs to determine whether (a) the rate of calcium reduction affected the PTH response to hypocalcemia and (b) the reduction in PTH values during a hypocalcemic clamp from the peak PTH value observed during the nadir of hypocalcemia was due to a depletion of stored PTH. METHODS: Fast (30 min) and slow (120 min) ethylenediamine-tetraacetic acid (EDTA) infusions were used to induce similar reductions in ionized calcium. In the fast EDTA infusion group, serum calcium was maintained at the hypocalcemic 30-minute value for an additional 90 minutes (hypocalcemic clamp). To determine whether the reduction in PTH values during the hypocalcemic clamp represented depletion of PTH stores, three subgroups were studied. Serum calcium was rapidly reduced from established hypocalcemic levels in the fast-infusion group at 30 and 60 minutes (after 30 min of a hypocalcemic clamp) and in the slow-infusion group at 120 minutes. RESULTS: At the end of the fast and slow EDTA infusions, serum ionized calcium values were not different (0.84 +/- 0.02 vs. 0.82 +/- 0.03 mM), but PTH values were greater in the fast-infusion group (246 +/- 19 vs. 194 +/- 13 pg/ml, P < 0.05). During the hypocalcemic clamp, PTH rapidly decreased (P < 0.05) to value of approximately 60% of the peak PTH value obtained at 30 minutes. A rapid reduction in serum calcium from established hypocalcemic levels at 30 minutes did not stimulate PTH further, but also PTH values did not decrease as they did when a hypocalcemic clamp was started at 30 minutes. At 60 minutes, the reduction in serum calcium increased (P < 0.05) PTH to peak values similar to those before the hypocalcemic clamp. The reduction in serum calcium at 120 minutes in the slow EDTA infusion group increased PTH values from 224 +/- 11 to 302 +/- 30 pg/ml (P < 0.05). CONCLUSIONS: These results suggest that (a) the reduction in PTH values during the hypocalcemic clamp may not represent a depletion of PTH stores. (b) The use of PTH values from the hypocalcemic clamp as the maximal PTH may underestimate the maximal secretory capacity of the parathyroid glands and also would change the analysis of the PTH-calcium curve, and (c) the PTH response to similar reductions in serum calcium may be less for slow than fast reductions in serum calcium.     

Primary hyperparathyroidism associated with hypocalcemia in a patient presenting with kidney disease

Elevated serum parathyroid hormone (PTH) level together with hypocalcemia in chronic kidney disease usually suggests secondary hyperparathyroidism. However, primary hyperparathyroidism should also be considered, especially if concomitant vitamin D deficiency is suspected. We report a case of parathyroid adenoma associated with hypocalcemia and metabolic bone disease in a patient presenting with kidney disorder. The patient was successfully treated by parathyroidectomy that was preceded and followed by intensive calcium and vitamin D supplementation.     

Direct effect of acute metabolic and respiratory acidosis on parathyroid hormone secretion in the dog.

Because both metabolic (Met Acid) and respiratory acidosis (Resp Acid) have diverse effects on mineral metabolism, it has been difficult to establish whether acidosis directly affects parathyroid hormone (PTH) secretion. Our goal was to determine whether acute Met Acid and Resp Acid directly affected PTH secretion. Three groups of dogs were studied: control, acute Met Acid induced by HCl infusion, and acute Resp Acid induced by hypoventilation. EDTA was infused to prevent acidosis-induced increases in ionized calcium, but more EDTA was needed in Met Acid than in Resp Acid. The PTH response to EDTA-induced hypocalcemia was evaluated also. Magnesium needed to be infused in groups receiving EDTA to prevent hypomagnesemia. The half-life of intact PTH (iPTH) was determined during hypocalcemia when PTH was measured after parathyroidectomy. During normocalcemia, PTH values were greater (p < 0.05) in Met Acid (92 +/- 19 pg/ml) and Resp Acid (77 +/- 22 pg/ml) than in controls (27 +/- 5 pg/ml); the respective pH values were 7.23 +/- 0.01, 7.24 +/- 0.01, and 7.39 +/- 0.02. The maximal PTH response to hypocalcemia was greater (p < 0.05) in Met Acid (443 +/- 54 pg/ml) than in Resp Acid (267 +/- 37 pg/ml) and controls (262 +/- 48 pg/ml). The half-life of PTH was greater (p < 0.05) in Met Acid than in controls, but the PTH secretion rate also was greater (p < 0.05) in Met Acid than in the other two groups. In conclusion, (1) both acute Met Acid and Resp Acid increase PTH secretion when the ionized calcium concentration is normal; (2) acute Met Acid may increase the bone efflux of calcium more than Resp Acid; (3) acute Met Acid acts as a secretogogue for PTH secretion because it enhances the maximal PTH response to hypocalcemia.     

Hormone secreting ability in patients with parathyroid autograft

In order to elucidate the function of parathyroid autograft, we determined the plasma parathyroid hormone (PTH) levels in the blood from cubital veins in two patients who had parathyroid autotransplantation after total parathyroidectomy. The first patient with chronic renal failure had been treated by hemodialysis for the past nine years and showed marked symptoms due to secondary hyperparathyroidism for five years. The second patient showed an evidence of recurrence of parathyroid cancer three years after the initial operation carried out elsewhere. The parathyroid tissue of 80 mg was sliced into 25 pieces and transplanted into separate pockets in one of the brachioradial muscles of the forearm. These patients showed an increase in plasma PTH levels two weeks after surgery. Plasma calcium level returned to the normal range three months after operation. Artificial hypocalcemia was induced by an injection of porcine calcitonin at ten months after surgery and a reserve of PTH secretion was tested. An increase of plasma C-PTH and N-PTH levels were recognized in the two patients as well as in the normal healthy volunteers. It was shown that parathyroid autograft has sufficient function to maintain normocalcemia and a reserve of function to respond against an artificially induced hypocalcemia at the tenth month after autografting.     

Outcomes of Parathyroid Autotransplantation During Total Thyroidectomy: A Comparison with Age- and Sex-Matched Controls

Purpose: To determine the effect of parathyroid autotransplantation (PA) on postoperative hypocalcemia in cases of total thyroidectomy. Materials and Methods: Cases undergoing total thyroidectomy and PA were compared with age and sex-matched controls who had not undergone PA. The postoperative percentage changes (PC) of parathyroid hormone (PTH) and calcium (Ca+2) in the first 12–24 hours (12–24hr→preop), between the 1st-3rd weeks (1-3wk→preop) and at the 6th month (6mo→preop), the rates of hypocalcemia (Ca+2< 8mg/dL) and low PTH level (PTH< 15 pg/mL), permanent hypocalcemia, inadvertent parathyroidectomy in both groups were compared. Results: The number of patients with PTH12-24hr<15 pg/mL was significantly higher (n:34,(55.7%)) than the number of patients in the control group (n:16(26.2%)), (p=0.001). The rate of decrease in the blood Ca+2 median PC (6mo→preop) was significantly higher in the PA group (4.2%) than the control group (1.1%), (p=0.008). There was no significant difference between the 2 groups in terms of the postoperative frequency of hypocalcemia (p>0.05). In the PA&age≤50 group, the rate of inadvertent parathyroidectomy was higher than that of cases over age 50 (p=0.029). Conclusion: In spite of the presence of an increased postoperative hypocalcemia trend in cases requiring PA during total thyroidectomy, the rates of transient and permanent hypocalcemia were not different to the control cases. But the frequency of cases with low PTH level in cases undergoing PA was higher than that of the control cases. In cases of 50 years of age and under, who had undergone PA, the possibility of inadvertent parathyroidectomy increased.     

A single-center experience of parathyroidectomy in 1500 cases for secondary hyperparathyroidism: a retrospective study

BackgroundChronic kidney disease (CKD) is a global public health problem. With the deterioration of renal function, a certain proportion of CKD patients enter the uremic stage, and secondary hyperparathyroidism (SHPT) becomes a challenge. For refractory hyperparathyroidism, parathyroidectomy (PTX) plays a key role in reducing mortality and improving prognosis. Nevertheless, no consensus has been reached on the optimal surgical method. We aimed to provide evidence for the effectiveness of surgical treatment by summarizing the experience from our center.MethodsClinical data from 1500 patients undergoing parathyroidectomy were recorded, which included 1419 patients in a total parathyroidectomy without autotransplantation (tPTX) group, 54 patients in a total parathyroidectomy plus autotransplantation (tPTX + AT) group, and 27 patients in the other group. Perioperative basic data, intact parathyroid hormone (i-PTH) levels, serum calcium levels, serum phosphorus levels, pathological reports, coexisting thyroid diseases, short-term outcomes and complications were analyzed. Moreover, postoperative complications were compared between the tPTX and tPTX + AT groups.ResultsParathyroid hormone, serum calcium and phosphorus levels decreased significantly post-surgery. Two patients died during the perioperative period. As the two most common complications, the incidences of severe hypocalcemia and hyperkalemia were 36.20% (543 cases) and 24.60% (369 cases), respectively. Pre-iPTH levels (OR = 1.001, 95% CI: 1.001–1.001, p < 0.01), serum alkaline phosphatase (ALP) levels (OR = 1.002, 95% CI: 1.001–1.002, p < 0.01) and the mass of excised parathyroid gland (OR = 3.06, 95% CI: 1.24–7.55, p = 0.02) were positively associated with postoperative severe hypocalcemia, while age and serum calcium were negatively associated with it. Pathological reports of resected parathyroid and thyroid glands indicated that 96.49% had parathyroid nodular hyperplasia, 13.45% had thyroid nodular hyperplasia, and 4.08% had thyroid papillary carcinoma.ConclusionsParathyroidectomy is a safe and effective treatment for refractory secondary hyperparathyroidism. Severe hypocalcemia is the main complication, and coexistent thyroid diseases should never be neglected.     

甲状旁腺切除治疗继发性甲状旁腺功能亢进

目的探讨甲状旁腺全切加自体移植及甲状旁腺次全切的2种手术治疗继发性甲状旁腺功能亢进（SHPT）的效果。方法根据19例SHPT患者甲状旁腺增生数目及腺体大小分为甲状旁腺全切加自体移植组及甲状旁腺次全切组,观察术后并发症,记录血清学指标,随访1年。结果腺体长径大于1cm病理改变且呈结节样增生。2组术后1个月钙、磷、碱性磷酸酶及甲状旁腺素水平变化无差异,术后1年碱性磷酸酶及甲状旁腺素变化存在显著统计差异。结论甲状旁腺切除治疗严重的SHPT效果确切,甲状旁腺全切加自体移植比甲状旁腺次全切复发率更小。     

Surgical management of secondary hyperparathyroidism

Most patients with renal failure maintained on chronic dialysis have elevated parathyroid hormone (PTH) levels and PTH-mediated bone disease (secondary hyperparathyroidism [sHPT]). Elevated PTH production in this setting represents a progressive, exaggerated physiologic response to hypocalcemia by the parathyroid glands, and generalized growth of the parathyroids is an adaptive response to chronic stimulation. Effective medical strategies to reduce PTH secretion and PTH-mediated bone turnover in sHPT (eg, controlling hyperphosphatemia, normalizing serum calcium, and administering vitamin D analogs) has decreased the need for parathyroidectomy in recent years. However, failure of medical therapy because of inadequate treatment, persistent hyperphosphatemia, or acquired parathyroid neoplasia still leads to recommendations for parathyroidectomy in select patients. Furthermore, increased awareness of potential long-term, irreversible cardiovascular effects of uncorrected hyperparathyroidism has led some to advocate parathyroidectomy earlier in the course of this disease. This monograph will review parathyroidectomy for secondary and tertiary hyperparathyroidism.     

Sigmoidal relationship between calcitonin and calcium: studies in normal, parathyroidectomized, and azotemic rats.

Calcitonin secretion is stimulated by acute hypercalcemia. Furthermore, in the rat, the calcemic response to parathyroid hormone (PTH) is decreased by calcitonin stimulation. However, in renal failure, it is not known if an increase in the serum calcium concentration within the physiologic range of serum calcium stimulates calcitonin and whether the increased calcitonin decreases the calcemic response to PTH. In the present study, four groups of pair-fed rats were evaluated: normals (N); parathyroidectomy (PTX); and two groups with renal failure (RF)--basal serum calcium less than 8.5 mg/dl (RFa) and basal serum calcium greater than 8.5 mg/dl (RFb). Hypocalcemia was induced by parathyroidectomy or in the RFa group, by a high phosphate diet. Increases in the serum calcium were produced by a 48 hour infusion of rat 1-34 PTH. In the RFa and PTX groups, stimulation of calcitonin was observed as the serum calcium increased from hypocalcemia to normal levels of calcium (P less than 0.01). In all four groups, increasing the serum calcium from normal levels to hypercalcemia increased the serum calcitonin level (P less than 0.05). The relationship between serum calcitonin and calcium was best expressed as a sigmoidal curve. In the two groups with basal hypocalcemia, PTX and RFa, the calcitonin-calcium curve was shifted to the left of the N and RFb groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

甲状旁腺全切＋自体移植术治疗继发性甲状旁腺功能亢进症疗效分析

目的探讨甲状旁腺全切＋自体移植术(tPTX＋AT)治疗维持性血液透析患者继发性甲状旁腺功能亢进症(SHPT)的有效性、安全性以及术后低钙的危险因素。 方法纳入我院2013年1月至2016年11月因SHPT行tPTX＋AT手术的维持性血液透析患者93例,收集术前术后症状、血钙、磷、碱性磷酸酶(ALP)、全段甲状旁腺激素(iPTH)、病理类型、并发症等临床资料。依据术后24 h血钙水平分为正常血钙组(Ca≥2.11 mmol/L)及低钙血症组(Ca<2.11 mmol/L),应用单因素分析及逐步Logistic回归分析术后早期低钙血症的危险因素。 结果手术成功率92.5%。切除360枚甲状旁腺腺体,异位甲状旁腺10枚。病理结果多为腺瘤样增生(96.4%)。同术前相比,术后血清iPTH、磷、ALP明显下降(P<0.05)。低钙血症是术后最常见并发症,发生率82.8%,血钙水平与术前血钙、年龄正相关(r＝0.300, P<0.01;r＝0.265, P<0.01),与术前iPTH、ALP水平负相关(r＝－0.461, P<0.01;r＝－0.477, P<0.01)。术前低血钙(OR＝0.113, P＝0.045)、高ALP水平(OR＝1.050, P<0.001)、高iPTH水平(OR＝1.002, P＝0.004)是术后早期低钙血症发生的独立危险因素。 结论tPTX＋AT可以安全、有效、快速的降低维持性血液透析患者血清iPTH水平,改善机体的钙磷代谢紊乱,但需重视并积极纠正术后低钙血症。针对存在术前低血钙、高iPTH及高ALP水平等高危因素的患者,术前积极纠正低钙血症可能是预防术后低钙的有效干预方式。     

术中甲状旁腺素监测在腔镜辅助甲状旁腺切除术中的应用

目的:探讨术中甲状旁腺素监测在腔镜辅助甲状旁腺切除术中的作用及效果。方法:回顾分析2006年10月至2012年12月有完整资料的10例腔镜辅助甲状旁腺切除患者的临床资料,其中男3例,女7例。患者术前血钙2.76～3.82 mmol/L,平均(2.87±0.69)mmol/L。术前甲状旁腺激素(parathyroid hormone,PTH)268.0～1390.8 pg/ml,平均(627.58±156.30)pg/ml。患者均通过B超、核素99mTc-MIBI(99锝m-甲氧基异丁基异腈)和/或CT定位。结果:10例均成功完成手术,无一例中转开放及再次探查手术。术中出血量平均(7.5±3.5)ml,手术时间平均(38.3±12.6)min。腺瘤切除后5 min,PTH平均(306.3±59.38)pg/ml;腺瘤切除后20 min,PTH平均(51.7±13.20)pg/ml,多降至正常。术后石蜡病理证实为甲状旁腺腺瘤,术后均无声嘶、呛咳、出血发生,2例发生短暂性低钙血症,术后随访9例患者2～73个月,美容效果满意,未见复发。结论:临床上内镜辅助甲状旁腺手术安全、可行,术后患者康复快,颈部美容效果好,术中结合甲状旁腺监测可有效保证手术的彻底性,避免盲目探查。     

Total parathyroidectomy without autotransplantation as a standard procedure in the treatment of secondary hyperparathyroidism

BACKGROUND: Total parathyroidectomy with autografting of parathyroid tissue and subtotal resection of the parathyroid glands are currently considered as standard surgical procedures for the treatment of severe secondary hyperparathyroidism. However, a considerable recurrence rate following these procedures ranges from 5% to 80%. We present a retrospective analysis of the results of parathyroidectomy with autotransplantation to the forearm versus parathyroidectomy alone. PATIENTS AND METHODS: We analyzed the clinical course of 11 consecutive patients who had undergone parathyroidectomy between 1995 and 1999, and who were not simultaneously autografted. Controls were 11 patients in whom autotransplantation of parathyroid tissue into the forearm had been routinely performed between 1993 and 1996 at our institution. Clinical symptoms and recurrence of hyperparathyroidism were assessed for comparison of the alternative treatment modalities. Recurrence of disease was defined by elevated parathormone (PTH) levels (>7.6 pmol/l) with clinical symptoms and/or need for reoperation. RESULTS: No recurrence of hyperparathyroidism was observed in patients without autotransplantation after a mean follow-up of 23 months (range 1-49). Measurement of intact serum PTH revealed residual PTH secretion even after removal of four glands (mean 2.02 pmol/l). Clinical symptoms improved substantially after surgery. In the historical control group 3 of the 11 autotransplanted patients (27%) required resection of transplanted tissue. Additionally, two patients (18%) presented with increased PTH secretion and clinical symptoms of recurrent hyperparathyroidism during follow-up. Thus, a total of five patients (45%) experienced relapsing hyperparathyroidism caused by the implanted tissue. CONCLUSIONS: Total parathyroidectomy without autotransplantation is a safe procedure with a low rate of recurrent hyperparathyroidism when compared to parathyroidectomy with autotransplantation to the forearm in a historical control. These preliminary results mandates further investigations including a randomized trial.     

A patient undergoing chronic dialysis whose renal anemia was successfully corrected by treatment with cinacalcet

A 62-year-old female dialysis patient with chronic glomerulonephritis had been receiving hemodialysis therapy for 32 years. In 1985 she underwent a parathyroidectomy for secondary hyperparathyroidism (HPT); however, her parathyroid hormone (PTH) levels gradually increased. Her serum calcium level ranged from 9.0 to 10.0 mg/dL, which caused difficulties in performing vitamin D injection therapy. No parathyroid glands were seen by echography or scintigraphy. On 31 March 2008 her intact PTH (iPTH) level was 895 pg/mL so treatment with cinacalcet 25 mg/day was started. After 3 months her iPTH level decreased to 269 pg/mL and her hemoglobin level increased from 9.3 to 12.9 g/dL. In some cases of severe HPT, anemia improves after parathyroidectomy; however, in this case, cinacalcet improved not only secondary HPT but also anemia.     

Different effects of calcitriol and parathyroidectomy on the PTH--calcium curve in dialysis patients with severe hyperparathyroidism

BACKGROUND: The PTH–calcium sigmoidal curve is shifted to the right,the slope of the curve is steeper, and the set point of calciumis increased in dialysis patients with secondary hyperparathyroidism,compared to patients with low-turnover bone disease. These findingscould be related to increased parathyroid cell mass and increasedsensitivity of parathyroid cells to serum calcium variationsin these patients. Calcitriol therapy has been documented toreduce PTH levels by shifting the curve to the left and downward.The effect of a surgical reduction of parathyroid gland masson the PTH-calcium curve has not yet been investigated. In thisstudy we compared the effects of calcitriol and subtotal parathyroidectomy(PTH) on the dynamics of PTH secretion in response to acutechanges of serum calcium in two groups of dialysis patientswith severe hyperparathyroidism. METHODS: Fourteen dialysis patients treated for 6 months with high-dosei.v. calcitriol (1–2 µg thrice weekly), and 10 dialysispatients who underwent subtotal PTx were studied. The PTH–calciumrelationship obtained by inducing hypo- and hypercalcaemia bymeans of low and high calcium dialysis was evaluated beforeand 2–6 months after treatment. RESULTS: Both calcitriol and subtotal PTx significantly decreased PTH(respectively from 797±595 to 380±244 and from1036±250 to 70±34 pg/ml), as well as maximal PTHresponse to hypocalcaemia (PTHmax), and maximal PTH suppressionduring hypercalcaemia (PTHmin). When the PTH–calcium curveswere constructed using PTHmax as 100% to factor for differencesin absolute PTH levels and to provide an assessment of individualparathyroid cell function, a shift of the sigmoidal curve tothe left and downward, and a significant decrease in the setpoint of ionized calcium (from 1.31±0.05 to 1.26±0.05and from 1.36±0.09 to 1.22±0.07 mmol/1) was documentedwith both treatments. However, the slope of the PTH–calciumcurve increased after subtotal PTx indicating that the sensitivityof the parathyroid cell to serum calcium changes increased withPTx, while on the contrary it decreased with calcitriol. CONCLUSIONS: PTH secretion decreases proportionally more with calcitriolthan with surgery for a given decrease in the functional massof parathyroid cells. The change in the PTH–ICa sigmoidalcurve induced by subtotal PTx is due to the removal of a largemass of parathyroid tissue with advanced hyperplasia.     

Hemithyroidectomy: long-term effects on parathyroid function--preliminary report

Early hypocalcemia after thyroid surgery has frequently been reported, whereas data regarding long-term effects on calcium homeostasis are scarce. We have previously studied patients after hemithyroidectomy with an oral calcium load test and found normal parathyroid hormone (PTH) suppression. However, the 1,25-dihydroxyvitamin D concentration was decreased and the phosphate concentration increased, implying parathyroid insufficiency. We therefore proceeded to investigate PTH secretion and suppression in 10 euthyroid patients subjected to hemithyroidectomy due to benign thyroid disease before and at 1 year after surgery. In addition, biochemical variables known to influence calcium homeostasis were analyzed. Basal, maximal, and total PTH secretion were unaltered 1 year postoperatively. However, maximal PTH secretion was reached at a lower serum level of ionized calcium, and there was a tendency toward increased parathyroid sensitivity to ionized calcium. Furthermore, compared to preoperative, total serum calcium, 1,25-dihydroxyvitamin D, and free thyroxine (T4) concentrations were decreased at follow-up. Total serum calcium and 1,25-dihydoxyvitamin D concentrations were decreased 1 year after hemithyroidectomy. These changes were not due to parathyroid insufficiency. Instead, our results imply increased parathyroid sensitivity to calcium and possibly reduced peripheral sensitivity to PTH.