Parathyroid Function In Patients Research Articles

Long-term effect of postoperative radioactive iodine therapy on parathyroid function in patients with differentiated thyroid cancer.

The study aimed to assess the impact of postoperative radioactive iodine (RAI) therapy on parathyroid function in patients who underwent total or subtotal thyroidectomy for differentiated thyroid cancer (DTC). Data from 150 patients treated with RAI for DTC and 76 patients with low-risk DTC not receiving RAI were retrospectively analyzed. Clinical characteristics, preoperative and 1-month postoperative biochemical parameters, and adjusted calcium, phosphorus, parathyroid hormone (PTH), and 25-hydroxyvitamin D3 (25-OH-D) levels at 3months, 1year, 3years, and 5years post-RAI (or in the low-risk group) were recorded. A total of 226 DTC patients were included in the study (80.5% female, mean age 42.7 ± 13.2years). Total thyroidectomy was performed in 97.3% (n = 220) of patients, with central lymph node dissection (CLND) in 41.6% (n = 94). No significant preoperative differences in PTH, aCa, P, Mg, or 25-hydroxyvitamin D3 levels were observed. However, patients receiving ≥ 3.7GBq (or 100mCi) RAI (n = 70) had lower calcium and PTH levels at the end of the first year following RAI treatment (p = 0.048, p = 0.032). The non-RAI group showed significantly higher calcium levels at one month postoperatively (p = 0.031) and lower rates of CLND and neck dissection. No significant differences in biochemical parameters were found at the five-year follow-up, except for one patient who developed normocalcemic hyperparathyroidism after RAI. High-dose RAI therapy may lead to transient decreases in calcium and PTH levels in the early post-treatment period. However, long-term parathyroid function appears to remain unaffected in DTC patients, regardless of the RAI dose administered. Nonetheless, close monitoring of calcium and PTH levels is recommended, particularly in the early post-treatment period, to promptly manage any potential transient hypoparathyroidism.

Assessment of thyroid and parathyroid function in patients treated for laryngeal carcinoma

Background The close proximity of both thyroid and parathyroid glands to the larynx puts them at high risk to develop hypofunction from the treatment of cancer larynx. Aim Thyroid and parathyroid function evaluation after treatment modalities of cancer larynx. Patients and methods Thyroid and parathyroid function was evaluated in 60 patients treated from laryngeal carcinoma. Patients were classified into three groups based on treatment type. Group 1 included patients with primary radiotherapy while group 2 included patients with total laryngectomy and group 3 involved patients with combined total laryngectomy and postoperative radiotherapy. Laboratory assessment of thyroid function included thyroid-stimulating hormone (TSH), free T4, while parathyroid function included corrected serum calcium and parathormone levels. The association of gland hypofunction was studied against tumor and treatment characteristics. Results Among the 60 patients; group 1 included 27 patients, group 2 included 21 patients, and group 3 included 12 patients. Twenty-five (41.7%) patients showed high TSH level and low FT4 level indicating clinical hypothyroidism while 12 (20%) patients showed high TSH level with normal FT4 level indicating subclinical hypothyroidism. Twenty-three (38.3%) patients showed normal levels of both TSH and FT4 being euthyroid. Concerning parathyroid function; 19 (31.7%) showed hypoparathyroidism diagnosed by low corrected serum calcium level and confirmed by low parathyroid hormone level. Conclusion The study detects the occurrence of hypothyroidism with or without hypoparathyroidism after treatment modalities of cancer larynx emphasizing the need of high clinical suspicion and routine evaluation for early detection of any post treatment thyroid or parathyroid gland hypofunction.

The Effects of Radioiodine Therapy on the Recovery of Parathyroid Function in Patients with Protracted Hypoparathyroidism after Total Thyroidectomy for Papillary Thyroid Carcinoma

Background To determine the effect of 131I treatment on postoperative parathyroid function and the timing of recovery of parathyroid function (RPF) in patients with protracted hypoPT. Methods 260 patients with papillary thyroid cancer (PTC) were retrospectively analyzed, including 166 patients treated with radioactive iodine-131 (131I) classified into the 131I group and 94 patients without 131I treatment classified into the control group. Data on clinicopathological characteristics, demographics, dose and interval time of 131I treatment, number of parathyroid glands remaining in situ (PGRIS), occurrence of hypoPT, duration of RPF, preoperative and postoperative levels of Ca and PTH were collected. Results The patients in the 131I group showed a higher persistent hypoPT rate than those in the control group (p = 0). The PGRIS and total number of PG were significantly higher in patients who recovered from protracted HypoPT (p = 0.02; p = 0.03). PGRIS and 131I treatment [1 ∼ 2 VS 0, p = 0.03, OR 3.19; 3 ∼ 4 VS 0, p = 0.02, OR3.62; p = 0.02, OR 1.98, respectively] were independent factors influencing postoperative persistent hypoPT. The timing of RPF differed significantly for patients in the control group compared to those in the 131I group [p = 0.00]. Conclusions We found that 131I treatment significantly prolonged the RPF of patients with protracted hypoPT and caused late RPF (even beyond 12 months). The diagnosis of “permanent” hypoPT should be cautiously made at least 12 months after surgery, especially in patients who receive 131I treatment.

Recovery of parathyroid function in patients with thyroid cancer treated by total thyroidectomy: An analysis of 685 patients with hypoparathyroidism at discharge of surgery

ObjectiveWe aimed to study the predictive factors for recovery of parathyroid function in hypoparathyroid patients after total thyroidectomy for thyroid cancer. MethodsWe designed a retrospective, multicentre and nation-wide analysis of patients with total thyroidectomy who were seen in twenty endocrinology departments from January to March 2018. We selected patients with histologically proven thyroid cancer and retrieved information related to surgical procedure and thyroid cancer features. Survival analysis and Cox regression analysis were used to study the relationship between these variables and the recovery of parathyroid function. ResultsFrom 685 patients with hypoparathyroidism at discharge of surgery, 495 (72.3%) recovered parathyroid function over time. Kaplan–Meier analysis showed that this recovery was significantly related to the presence of specialized surgical team (P<0.001), identification of parathyroid glands at surgery (P<0.001), papillary histopathology (P=0.040), and higher levels of postoperative calcium (Ca) (P<0.001) and parathyroid hormone (PTH) (P<0.001). Subjects with gross extrathyroidal extension (P=0.040), lymph node metastases (P=0.004), and surgical re-intervention after initial surgery (P=0.024) exhibited a significant risk of persistence of hypoparathyroidism. Multivariate Cox regression analysis showed that the significant and independent factors for recovery of parathyroid function were postoperative concentrations of Ca (P=0.038) and PTH (P=0.049). The presence of lymph node metastases was a negative predictor of recuperation of parathyroid function (P=0.042) in this analysis. ConclusionIn patients with thyroid cancer, recovery of parathyroid function after total thyroidectomy was directly related to postoperative Ca and PTH concentrations, and inversely related to lymph node metastases.

Duration of Parathyroid Function Recovery in Patients With Protracted Hypoparathyroidism After Total Thyroidectomy for Papillary Thyroid Carcinoma.

PurposeThe aim of the present study is to investigate the time to recovery of parathyroid function in patients with protracted hypoparathyroidism at 1 month after total thyroidectomy of papillary thyroid carcinoma.Materials and MethodsAdult patients who underwent total thyroidectomy for papillary thyroid cancer were included. Cases of long-term hypoparathyroidism were studied for recovery of parathyroid function during the follow-up. The duration of recovery and associated variables were recorded.ResultsOut of the 964 patients, 128 (13.28%) developed protracted hypoparathyroidism and of these, 23 (2.39%) developed permanent hypoparathyroidism and 105 (10.89%) recovered: 86 (8.92%) before 6 months, 11 (1.14%) within 6 and 12 months and 8 (0.83%) after 1 year follow-up. Variables significantly associated with the time to parathyroid function recovery were number of autotransplanted parathyroid glands (HR, 1.399; 95% CI, 1.060 – 1.846; P = 0.018), serum calcium concentration >2.07 mmol/L (Hazard ratio [HR], 1.628; 95% confidence interval [CI], 1.009 – 2.628; P = 0.046) and PTH level > 1.2 pmol/L (HR, 1.702; 95% CI, 1.083 – 2.628; P = 0.021) at 1 month postoperatively.ConclusionPermanent hypoparathyroidism should not be diagnosed easily by time, since up to one-fifth of the patients will experience recovery after a period of 6 months and a few patients even beyond one year. The number of autotransplanted parathyroid glands is positively associated with the time to parathyroid function recovery.

Recovery of parathyroid function in patients with thyroid cancer treated by total thyroidectomy: An analysis of 685 patients with hypoparathyroidism at discharge of surgery

ObjectiveWe aimed to study the predictive factors for recovery of parathyroid function in hypoparathyroid patients after total thyroidectomy for thyroid cancer. MethodsWe designed a retrospective, multicentre and nation-wide analysis of patients with total thyroidectomy who were seen in twenty endocrinology departments from January to March 2018. We selected patients with histologically proven thyroid cancer and retrieved information related to surgical procedure and thyroid cancer features. Survival analysis and Cox regression analysis were used to study the relationship between these variables and the recovery of parathyroid function. ResultsFrom 685 patients with hypoparathyroidism at discharge of surgery, 495 (72.3%) recovered parathyroid function over time. Kaplan–Meier analysis showed that this recovery was significantly related to the presence of specialized surgical team (P<0.001), identification of parathyroid glands at surgery (P<0.001), papillary histopathology (P=0.040), and higher levels of postoperative calcium (Ca) (P<0.001) and parathyroid hormone (PTH) (P<0.001). Subjects with gross extrathyroidal extension (P=0.040), lymph node metastases (P=0.004), and surgical re-intervention after initial surgery (P=0.024) exhibited a significant risk of persistence of hypoparathyroidism. Multivariate Cox regression analysis showed that the significant and independent factors for recovery of parathyroid function were postoperative concentrations of Ca (P=0.038) and PTH (P=0.049). The presence of lymph node metastases was a negative predictor of recuperation of parathyroid function (P=0.042) in this analysis. ConclusionIn patients with thyroid cancer, recovery of parathyroid function after total thyroidectomy was directly related to postoperative Ca and PTH concentrations, and inversely related to lymph node metastases.

The effect of operative approach selection on the protection of parathyroid function in thyroid cancer

Objective: To investigate the effect of endoscopic thyroidectomy and open thyroidectomy on parathyroid function in patients with thyroid cancer. Methods: The clinical data of 73 patients with thyroid cancer who met the inclusion criteria in Zhengzhou Central Hospital Affiliated to Zhengzhou University from July 2018 to September 2019 were retrospectively analyzed, including 17 males and 56 females, aged 19-55 years. The patients underwent routine thyroidectomy (group A, n=31), oral endoscopic thyroidectomy by vestibular approach (group B, n=19) or transthoracic thyroidectomy (group C, n=23), and all patients received central neck dissection. The levels of parathyroid hormone (PTH) and serum calcium after operation were compared among three groups. SPSS 21.0 software and GraphPad Prism v6.01 were used for statistical analysis. Results: After operation, the mean levels of PTH and serum calcium in three groups were significantly decreased (all P<0.05). On the first day after operation, the mean level of PTH in group C was lower than that in group A [(12.3±9.0) vs. (22.2±13.2) pg/ml, t=3.04, P=0.004] or group B [(12.3±9.0) vs. (20.0±14.1) pg/ml, t=2.09, P=0.043], and also the level of serum calcium in group C was lower than that in group A [(1.89±0.11) vs. (2.02±0.16) mmol/L, t=3.24, P=0.002] or group B [(1.89±0.11) vs. (2.01±0.15) mmol/L, t=2.72, P=0.010], with no significant difference in the mean levels of PTH or serum calcium between group A and group B (t=0.54, 0.29, respectively, both P>0.05). The incidences of permanent hypoparathyroidism/persistent hypocalcemia were 3.2% (1/31) in group A, 5.3% (1/19) in group B and 21.7% (5/23) in group C, and the incidence of group C was significantly higher than that (4%, 2/50) of both group A and group B (χ(2)=5.251, P=0.022). Conclusion: The postoperative parathyroid function and serum calcium level have different degrees of change and they are significantly associated with thyroidectomy approaches, the protection of parathyroid by oral endoscopic thyroidectomy and routine thyroidectomy can achieve the same effect, and is better than that of transthoracic thyroidectomy.

Effect of Post-Surgical Rai Therapy on Parathyroid Function in Patients with Differentiated Thyroid Cancer

Objective: Radiotherapy with radioactive iodine (RAI) has become a common treatment for postsurgical differentiated thyroid carcinoma (DTC). The objective of this study was to determine the effect of RAI therapy following surgery on the function of the parathyroid glands in DTC patients. Methods: A total of 81 DTC patients who received RAI therapy after surgery were enrolled in the study. The size of the residual thyroid was detected by technetium-99m (99mTc)-pertechnetate thyroid scan (99mTc thyroid scan) before RAI therapy. The iodine uptake ability of residual thyroid was evaluated by iodine-131 (131I) whole-body scan (WBS). All patients were treated with an activity of 3.7 GBq (100 mCi) 131I. Parathyroid hormone (PTH), serum calcium, phosphorus, and magnesium were evaluated at 1 day before treatment, and at 1 month and 3 months after treatment. Results: The results show that there was no statistically significant difference in blood PTH level observed (P>.05) between 3 time points (pre-treatment, 1 month post-treatment and 3 months post-treatment). The serum calcium and phosphorus did not change significantly (P>.05), but serum magnesium level was elevated after treatment (P<.05). There were no significant differences between PTH changes and sex, age, scores of 99mTc thyroid scan, scores of 131I WBS, Tumor (T) stage, and Node (N) stage. Conclusion: RAI therapy following surgery did not significantly affect parathyroid function in DTC patients. Abbreviations: ATA = American Thyroid Association; DTC = differentiated thyroid carcinoma; FT3 = free triiodothyronine; FT4 = free thyroxine; 131I = iodine-131; PTH = parathyroid hormone; RAI = radioiodine; 99mTc = Technetium-99m; TG = thyroglobulin; TNM = Tumor Node Metastasis; TSH = thyroid-stimulating hormone; WBS = whole-body scan.

Prediction of hypocalcemia after total thyroidectomy using indocyanine green angiography of parathyroid glands: A simple quantitative scoring system

BackgroundHypocalcemia is one of the most common complications after total thyroidectomy. Recently, indocyanine green (ICG) angiography of the parathyroid glands (PGs) has been suggested as a reliable tool for predicting postoperative hypocalcemia. The aim of our study was to evaluate the performance of a simple quantitative score based on ICG angiography of the PGs (4-ICG score) for predicting postoperative hypocalcemia. MethodsThirty nine consecutive patients who underwent total thyroidectomy for multinodular goiter were included. For each patient, the 4-ICG score was calculated, adding the individual viability value of the four PGs. Discrimination and correlation analyses were performed. ResultsIn 32/39 patients, the four PGs were identified. Patients with postoperative hypocalcemia (n = 6, 19%) had a lower 4-ICG score (2.5 [1.8–3.3] vs. 4.0 [3.0–6.0]; p = 0.003). The 4-ICG score showed good discrimination in terms of predicting postoperative hypocalcemia (AUC = 0.875 (0.710–0.965); p = 0.001) and a good correlation with postoperative parathyroid function. ConclusionsThe 4-ICG score predicts postoperative hypocalcemia and correlates well with postoperative parathyroid function in patients undergoing total thyroidectomy for multinodular goiter.

Preserving Parathyroid Gland Vasculature to Reduce Post-thyroidectomy Hypocalcemia.

The failure to preserve parathyroid function in patients who have undergone total thyroidectomy is of major concern, because hypocalcemia is difficult to prevent and remains a common postoperative complication. Here, we describe procedures designed to preserve the vasculature supplying the parathyroid glands and examine both recent outcomes and retrospective reports of results obtained prior to the application of these preservation techniques. Our technique for preserving parathyroid function during thyroidectomy was adopted in 2009 and involves separating a relatively long segment of a vessel distally from the thyroid gland. We reviewed the medical records of 1,411 patients who underwent total thyroidectomy, with or without lateral neck dissection, at the Samsung Medical Center from January 2006 through June 2014 to determine outcomes. Patients were divided into three groups according to the time period during which the surgery took place: Group A, 2006-2008 (before the vasculature-preserving technique was applied); Group B, 2009-2011 (the time when the technique was first adopted); and Group C, 2012-2014 (more recent results of the technique). We analyzed the incidence of hypoparathyroidism in the three groups, as well as risk factors that influenced its development. The rates of transient and permanent hypoparathyroidism in Group A were 25.4 and 4.3%, respectively. However, the incidence of hypoparathyroidism decreased significantly over time after the vasculature-preserving procedure was adopted. Transient hypoparathyroidism developed in 4.8% of Group C patients, and only four (0.7%) of the 565 patients in this group required calcium supplementation, despite the fact that a greater number of patients were included who underwent total thyroidectomy combined with lateral neck dissection. Although female sex and lateral neck dissection tended to increase the rate of transient hypoparathyroidism, multivariate analysis showed that the vasculature-preserving procedure was the only significant risk factor related to postoperative hypoparathyroidism. The blood flow of the final branch to the parathyroid gland is mostly in the lateral-to-medial direction; therefore, mobilization and preservation of the vessels lateral to the gland is essential to prevent devascularization of the parathyroid gland.

Parathyroid gland function after radioiodine (131I) therapy for toxic and non-toxic goitre

The therapeutic effect of radioactive iodine ((131)I) on benign goitre consists of the emission of tissue-destructive beta-radiation. Since the range of beta (131)I radiation in tissue can reach 2.4 mm, it can affect the adjacent parathyroid glands. The purpose of this paper is to assess parathyroid function in patients with toxic and non-toxic goitres, up to five years following (131)I therapy. The study sample consisted of 325 patients with benign goitres (220 with toxic nodular goitre (TNG), 25 with non-toxic nodular goitre (NTNG), and 80 with Graves' disease (GD) treated with (131)I. The therapeutic activity of (131)I for each patient was calculated using Marinelli's formula. The serum levels of fT3, fT4, TSH, iPTH and Ca(2+), Ca and phosphates were determined one week before (131)I administration, as well as every two months up to a year following the therapy, and then after three and five years post-treatment. After two months following the administration of (131)I, all the treated patients showed a statistically significant above normal increase in iPTH concentrations (amounting to a value almost twice the norm in patients with TNG), which remained stable up to ten months after treatment, to return to normal level in the following months. In all the patients, Ca(2+), Ca, phosphates concentration remained within normal range throughout the course of the study. The concentrations of fT3 and fT4 quickly returned to normal after (131)I administration, and remained within normal range until the completion of the study. Radioiodine treatment of benign thyroid disorders results in transient (up to ten months after (131)I administration) hyperparathyroidism. The condition does not influence the level of calcium and phosphates concentration in any significant way.

Novel Electrochemiluminescence Immunoassay Exclusively for Full‐length Parathyroid Hormone during Treatment with Cinacalcet for Secondary Hyperparathyroidism

A novel, electrochemiluminescence immunoassay that exclusively measures full-length parathyroid hormone (PTH), called Elecsys PTH (1-84) assay, is currently under development for clinical use. We measured serum PTH levels using this novel assay, as well as the Elecsys Intact PTH assay and the Whole PTH immunoradiometric assay, in 53 hemodialysis patients who participated in a 52-week clinical trial of cinacalcet. At baseline, serum PTH (1-84) levels measured with the Elecsys PTH (1-84) assay and those with the Whole PTH assay were comparable, and both values were significantly lower than Elecsys Intact PTH levels. After 52 weeks of cinacalcet treatment, Elecsys PTH (1-84) levels and Whole PTH levels decreased significantly by 56% and 60% from baseline, respectively. These results indicate that the Elecsys PTH (1-84) assay provides comparable data to the Whole PTH assay for monitoring parathyroid function in patients receiving hemodialysis. Introduction of this novel automated immunoassay would provide more widespread measurements of full-length PTH (1-84) in clinical practice.

Calcium-Corrected Intact PTH: A Clinically Useful Parameter for Quantifying Parathyroid Function in Patients Undergoing Hemodialysis

Background/Aims: Serum parathyroid hormone (PTH) concentration provides a rough index of the severity of secondary hyperparathyroidism (SHPT) due to chronic renal failure. Since serum PTH inversely related to calcium (Ca) level, we attempted to create a new index based on the relationship. Methods: Our subjects were 70 patients undergoing maintenance hemodialysis (HD) in a single facility. Using multiple pairs of serum Ca corrected for albumin (cCa) and intact PTH (iPTH) values drawn simultaneously, we determined the steepest slope of cCa-iPTH relationship for each individual patient to get a line closely resembling the cCa-PTH sigmoidal curve. Results: Based on the slopes, the following equation was obtained: iPTH2 = iPTH1 + (cCa1 – cCa2) × (43 + 0.47 × iPTH1), where the PTH values at any 2 arbitrary values of cCa1 and cCa2 were assumed to be iPTH1 and iPTH2, respectively. When ‘corrected PTH’ is defined as the predicted value of iPTH at cCa = 9.0 mg/dl, its correlation was better than iPTH with the total volume of the parathyroid glands estimated by ultrasonography. Similar results were found in 30 parathyroidectomized patients at other facilities. Conclusion: ‘Corrected PTH’ may represent a useful parameter for assessing the severity of SHPT from single determinations of cCa and iPTH drawn at the same time.

Bone mineral density and parathyroid function in patients on maintenance hemodialysis

The relationship between parathyroid function, an important determinant of bone turnover, and bone mineral density (BMD) in patients with chronic kidney disease is not fully understood. We wanted to analyze the association between BMD and parathyroid function in hemodialysis patients in details. In a cross-sectional design, data from 270 patients (age 55±15years, 60% men, all Caucasian) on maintenance hemodialysis were analyzed. All patients underwent dual energy X-ray absorptiometry of the lumbar spine (LS), femoral neck (FN) and distal radius (DR). In addition to routine laboratory tests, blood samples were collected for iPTH, serum markers of bone metabolism (alkaline phosphatase, type I collagen crosslinked-C-telopeptide) and 25OH vitamin D. Based on Z-scores, bone mineral density was moderately reduced only at the femoral neck in the total cohort. The average Z-score of the "low PTH" group (iPTH<100pg/ml) was not different from the Z-score of patients with iPTH in the "target range" (100-300pg/ml) at any measurement site. While iPTH was negatively correlated with BMD at all measurement sites in patients with iPTH>100pg/ml (rho=-0.255, -0.278 and -0.251 for LS, FN and DR, respectively, P<0.001 for all), BMD was independent of iPTH in patients with iPTH<100pg/ml. Furthermore, iPTH was not associated with serum markers of bone metabolism, but these markers were negatively correlated with BMD in the "low PTH" group. Low PTH levels are not associated with low BMD in patients with end-stage kidney disease. Furthermore, bone metabolism seems to be independent of iPTH in patients with relative hypoparathyroidism likely reflecting skeletal resistance to PTH.

Parathyroid changes after high dose radioactive iodine in patients with thyroid cancer

The study aimed to investigate the effect of high dose radioactive iodine (RAI) on parathyroid function in patients with differentiated thyroid cancer. Nineteen patients (8 men/11 women, age 46.5 +/- 13.2 years) undergoing RAI for thyroid remnant ablation were enrolled in the study. The biochemical parameters related to parathyroid function [serum calcium (Ca), phosphate (P), creatinine (Cr), alkaline phosphatase (ALP), intact parathyroid hormone (iPTH), urinary Ca, cAMP concentrations and the maximum tubular capacity for phosphate per unit volume of glomerular filtrate (TmP/GFR)] were evaluated at baseline and at the 1st, 3rd, 6th and 12th months of RAI administration. SPSS 15.0 was used for statistical analysis. For all patients, thyroid-stimulating hormone levels were >30 U/ml at baseline and <0.1 U/ml at the following visits. Serum iPTH levels were decreased significantly at the 6th month and reached basal levels at the 12th month (baseline vs. 6th p = 0.027, 1st vs. 6th p = 0.011, 3rd vs. 6th p = 0.047, 3rd vs. 12th p = 0.014, 6th vs. 12th p = 0.001). At the 6th month, P and TmP/GFR levels were higher (p = 0.036, 0.017, respectively), and urinary cAMP measurements were lower (p = 0.020) compared to those of the 1st month. No difference was detected concerning the other parameters. Serum Ca levels decreased below 2.1 mmol/l in several patients (n = 5 at 1st month, n = 4 at 3rd month, n = 8 at 6th month and n = 3 at 12th month) without clinical symptoms. The study indicated a transient decline in PTH levels at the 6th month following RAI therapy. Although this decrease did not cause symptoms in any of the present cases, this pattern might be important especially in individuals with diminished parathyroid background.

Correlations between Vitamin D Status and Biochemical/Clinical and Pathological Parameters in Primary Hyperparathyroidism

To determine the prevalence of vitamin D deficiency and the effects of vitamin D status on parathyroid adenoma weight, clinical and biochemical indices in patients with primary hyperparathyroidism (pHPT) were studied. Eighty patients with pHPT who underwent surgical treatment and in whom the presence of parathyroid adenoma were confirmed histopathologically were studied retrospectively from recorded data files. Patients were divided into three groups: patients with 25-hydroxyvitamin D (25-OHD) concentrations < 15 ng/ml (group 1, n = 44), patients with 25-OHD concentrations > 15-25 ng/ml (group 2, n = 9), and patients with 25-OHD concentrations > 26 ng/ml (group 3, n = 27). Serum calcium, phosphate, alkaline phosphatase, creatinine, and albumin levels and urinary calcium excretion were determined by auto-analyzer. Plasma 25-OHD and parathyroid hormone (PTH) levels were determined by immunoradiometric assay using commercially available kits. No statistically significant differences were observed with respect to serum calcium, phosphorus, albumin, and creatinine concentrations between these groups. Serum PTH, alkaline phosphatase concentrations, urinary calcium excretion, parathyroid adenoma weight, and postoperative sixth month PTH concentrations were significantly higher in group 1 patients than in group 2 and group 3 patients. Significant correlations were observed between parathyroid adenoma weight and serum 25-OHD concentrations (r = -0.348, P = 0.020); parathyroid adenoma weight and urinary calcium excretion (r = 0.348, P = 0.021). Multiple regression analysis revealed that parathyroid adenoma weight, serum 25-OHD, and preoperative PTH concentrations correlated independently and significantly with postoperative sixth month PTH concentrations. Vitamin D deficiency leads to more severe bone disease, increased parathyroid tumor growth, and delayed postoperative recovery of parathyroid function in patients with primary hyperparathyroidism.

Control of Parathyroid Function in Patients with a Short History of Hemodialysis

Secondary hyperparathyroidism (SHPT) is one of the serious complications in patients with chronic kidney disease. Parathyroid glands secrete parathyroid hormone (PTH), stimulated partly by hyperphosphatemia and hypocalcemia complicating chronic kidney disease (CKD). Use of a calcium-based phosphate binder might be sufficient to reduce serum PTH levels in mild SHPT, while the recent K/DOQI clinical guidelines recommended vitamin D therapy for dialysis patients with serum level of intact parathyroid hormone of 300 pg/mL or more. We conducted a 6-month prospective controlled trial of 50 patients initiating hemodialysis therapy who were randomized to receive oral calcium carbonate alone or the drug plus oral vitamin D sterol, calcitriol or alfacalcidol. The primary end point was the proportion of randomized patients who had a mean PTH level of 300 pg/mL or less at the end of this study. The secondary end point included the percent change in the values for corrected calcium, phosphorus, the calcium-phosphorus product, and PTH. Eighty percent of patients receiving calcium carbonate without vitamin D sterols (20 of 25) reached the primary end point-a mean PTH level of 300 pg/mL or less after the period-as compared with 84% of those receiving calcium carbonate and vitamin D sterol (21 of 25) (Mantel-Haenszel odds ratio 0.76, 95% confidence interval: 0.18-3.25, P = 0.71). The other effects of the two regimens on the secondary end points were not significantly different after 6 months. In SHPT of dialysis patients initiating hemodialysis, oral calcium carbonate use alone was not inferior to additional vitamin D sterol use with calcium carbonate in reducing serum PTH levels. Our result indicated that, if serum calcium and phosphorus levels are controlled primarily regardless of used agents, it will be followed by reduction of serum PTH level in these patients.

Surgical verification of percutaneous maxacalcitol injection therapy on enlarged parathyroid glands in chronic dialysis patients.

Selective percutaneous ethanol injection therapy (PEIT) has been used to control parathyroid function in patients with secondary hyperparathyroidism (2HPT) when one or more parathyroid gland (PTG) progresses to the nodular hyperplasia stage. However, PEIT can have adverse side effects, such as nerve paralysis and adhesion, because the ethanol is destructive. Intraparathyroid injection of a vitamin D analogue has been designed as a treatment to control parathyroid function without destruction of the PTG or causing adhesions to the surrounding tissue, and the present study aimed to verify the effect of percutaneous maxacalcitol (22-oxacalcitriol) as the vitamin D analogue. The study group comprised two haemodialysis patients who needed parathyroidectomy for uncontrolled 2HPT with a maximal PTG diameter >20 mm. The treatment began with an ultrasonographically guided injection of 10 microg of maxacalcitol solution into the largest PTG and, 1 week later, parathyroidectomy was performed to examine the effect of the maxacalcitol injection both macroscopically and microscopically. The injected glands were swollen and inflamed, and adhesions made it difficult to remove them. There was macroscopic and microscopic evidence of haemorrhagic necrosis and adhesions to the surrounding tissue. Direct vitamin D analogue injection should not be performed as a primary treatment option because the adverse side effects are not overcome by this technique.

Vitamin D Receptor Gene Polymorphism Detected by Digestion with Apa I Influences the Parathyroid Response to Extracellular Calcium in Japanese Chronic Dialysis Patients

Background: To play its physiological role, 1,25(OH)₂D₃ must bind to a specific vitamin D receptor (VDR) in the nucleus. We have previously reported that VDR gene polymorphism influences the parathyroid function in patients with end-stage renal disease (ESRD). In the present study, we have investigated the relationship between the parathyroid responsiveness and VDR gene polymorphism, as detected by the Apa I restriction enzyme, by changing the concentration of Ca²⁺ in the dialysate. Methods: 58 Japanese ESRD patients undergoing renal replacement therapy in our institution were evaluated. Genomic DNA was extracted from peripheral leukocytes and digested at the intron between exon 8 and exon 9 of the VDR gene using Apa I enzyme. Then alleles were classified into genotype A (undigested allele) and genotype a (digested allele). Extracellular ionized calcium ([Ca²⁺]_e), serum phosphate, and intact parathyroid hormone (PTH) were measured before and after each hemodialysis (HD) session with dialysates having different concentrations of Ca²⁺ (1.5 or 1.25 mmol/l). The significance of differences in statistical analyses was defined within confidence limits of 5.0%. Results: The AA, Aa, and aa genotypes were observed in 7/58 patients (12.1%), 23/58 patients (39.6%), and 28/58 patients (48.3%), respectively. The PTH reduction after HD with the 1.5-mmol/l Ca dialysate did not differ significantly between group AA+Aa and group aa. On the other hand, the PTH increase was significantly higher in group aa than in group AA+Aa after HD with the 1.25-mmol/l Ca dialysate (p = 0.0107), despite a similar PTH level before HD. Similarly, the percent increase of PTH after HD with the 1.25-mmol/l Ca dialysate was significantly higher (p = 0.0112) in group aa (50.2 ± 9.4%) than in group AA+Aa (19.7 ± 7.2%). There were no significant differences between the two groups in [Ca²⁺]_e nor in serum phosphorus (Pi) before and after HD with either dialysate. Group AA+Aa and group aa did not show statistically significant differences in age, female/male ratio, ratio of diabetic nephropathy, or dialysis period. Conclusions: The study results showed that the patients in group aa were more sensitive to changes in [Ca²⁺]_e than those in group AA+Aa. Moreover, they suggested that the VDR gene polymorphism may affect parathyroid responsiveness to changes in [Ca²⁺]_e, which in turn may influence onset and progression of hyperparathyroidism in ESRD patients.

Potential factors regulating serum parathyroid hormone in maintenance hemodialysis patients: 4-year retrospective study

Background. This study was carried out to evaluate potential factors affecting long-term parathyroid function in patients on maintenance hemodialysis.