Decrease In Parathyroid Hormone Concentration Research Articles

An individual approach to intraoperative parathyroid hormone measurement during total thyroidectomy

PurposeHypocalcemia is a common complication of thyroidectomy. Measurement of the intraoperative serum parathyroid hormone (PTH) levels became an established technique but it requires further improvements. We aimed to assess intraoperative PTH level testing results against the hypothesis that the PTH assay may be performed almost immediately after thyroid gland removal. MethodsA retrospective cohort study. During total thyroidectomy surgery, the patients had PTH levels measured at the cutting time and again immediately after the thyroid gland is removed. Post-operatively, serial total blood calcium levels were obtained twice daily and recorded. ResultsAmong 63 enrolled patients, 39 had multinodular goiter, 15 thyroid carcinoma, and nine had Graves' disease. The mean age was 59.8 ± 15.3 years, 43 females. The mean PTH level before surgery was 45.8 ± 22.0 pg/mL. Post-operatively, 11/63 patients developed hypocalcemia with serum calcium levels <8 mg/dL. Four patients with ≥50 % decrease in PTH concentration were normocalcemic a day after surgery and were discharged early. Four patients with ≥70 % PTH decrease were treated accordingly during prolonged hospitalization and did not suffer from permanent hypocalcemia. The cut-off value of 70 % decrease after the gland removal was able to predict postoperative hypocalcemia with a sensitivity of 100 %, specificity 82.9 %, PPV 60.0 % and NPV 100 %. ConclusionMeasurements of intraoperative PTH may not be performed at fixed time intervals but after 1–2 min after removal of the thyroid gland. Defining those not at risk would allow the majority of patients to be waived from post-operative blood calcium testing and safely discharged early after surgery.

Clinical application of bone turnover markers in treating osteoporotic vertebral compression fractures and their role in predicting fracture progression.

This study aimed to investigate whether changes in the bone turnover markers (BTMs) during teriparatide therapy for osteoporotic vertebral compression fractures could reflect therapeutic effects by analyzing the relationship between clinical and radiological features and BTMs.A total of 33 patients with 51 osteoporotic vertebral compression fracture segments were included. Plain radiographs and BTM levels were evaluated at the pretreatment and at 3 months after teriparatide treatment. Based on serial vertebral compression ratio analysis, the progression of fracture was defined as a vertebral compression ratio decrease of ≥10%, relative to the pretreatment values.All segments were divided into 2 groups: the “maintain” group with 32 (62.7%) segments and the “progression” group with 19 (37.3%) segments. After the teriparatide treatment, serum osteocalcin and serum C-terminal telopeptide of type I collagen levels (P = .028 and .008, respectively), and change amounts of them were significantly larger, increasing (P = .001) in the progression group. The vitamin D (25OH-D) levels were significantly lower (P = .038) in the progression group; however, the relative changes in the 25OH-D levels between the 2 groups, before and after the treatment, were not significantly different (P = .077). The parathyroid hormone (PTH) levels were reduced by the teriparatide treatment in both groups, while the decrease in PTH concentration after the treatment was significantly more pronounced in the progression group (P = .006). Significant increase in the osteocalcin and serum C-terminal telopeptide of type I collagen levels and a simultaneous decrease in the PTH levels during the teriparatide treatment suggest that clinicians should assume the progression of fracture.

Experience with cinacalcet in primary hyperparathyroidism: results after 1 year of treatment

To assess the characteristics of patients with primary hyperparathyroidism (PHPT) treated with cinacalcet and to evaluate its efficacy in reducing serum calcium and parathyroid hormone (PTH) concentrations after 1 year of treatment. The study included 20 patients with PHPT who had completed at least 12 months of treatment with cinacalcet (eight patients for refusal of parathyroidectomy, three for surgery not possible due to comorbidities and nine for progressive hypercalcemia prior to surgery). We recorded clinical and biochemical data at baseline, and after 3, 6 and 12 months of treatment. We also monitored adverse events. Cinacalcet was administered in increasing doses until normal serum calcium was reached or side effects preventing a further increase occurred. After 3 months of treatment, serum calcium significantly decreased (11.73 ± 0.85 versus 10.71 ± 1.63 mg/dl, p < 0.001) and serum phosphorus significantly increased (2.41 ± 0.48 versus 2.63 ± 0.70 mg/dl, p = 0.004) while no significant change occurred in PTH (181.91 ± 102.37 versus 195.47 ± 111.71 pg/ml, p = 0.695). No further variation was observed after 6 months compared with 3 months of follow up. However, after 12 months of treatment, there was a significant decrease in PTH concentrations compared with baseline (181.91 ± 102.37 versus 152.47± 70.16 pg/ml, p = 0.028) as well as serum calcium (11.73 ± 0.85 versus 10.20± 0.95 mg/dl, p < 0.001); serum phosphorus significantly increased (2.41 ± 0.48 versus 2.71 ± 0.43 mg/dl, p = 0.01). Normocalcemia (S-Ca < 10.2 mg/dl) was achieved in 55% of patients. The medication was usually well tolerated (83.4%). Most common adverse events were nausea and vomiting, especially at the beginning of therapy. Cinacalcet rapidly reduced serum calcium in patients with PHPT and this reduction remained stable after 1 year of treatment. We also observed a decrease in PTH. Cinacalcet is an effective alternative in nonsurgical treatment of PHPT and may be useful in the preoperative hypercalcemia management.

Extremely high parathyroid hormone concentrations associated with pityriasis rubra pilaris and monoclonal gammopathy of unknown significance: A clinical dilemma

We present a case with extremely high parathyroid hormone (PTH) concentrations in the order of hundred thousands accompanied by dermatological and hematological diseases. After several diagnostic interventions, no malignancy could be demonstrated except monoclonal gammopathy of unknown significance. The dermatological findings were taken to be manifestations of the hematological disease. Since the first serum intact PTH concentration of the patient was found to be higher than 2500pg/ml, dilution study was performed and found to be 215,977pg/ml. The high concentration of serum PTH was taken to be falsely high due to assay interference. This concentration was checked from three different paths; a test for linear dilution was performed, the test was repeated with another method and the sample was treated to remove or inhibit interfering substances. The results were compatible with endogenous antibody interference, presumed to be a result of monoclonal gammopathy. The extremely high PTH concentrations were not only due to assay interference, but also secondary hyperparathyroidism, which was evident by the decrease in PTH concentrations with calcium and vitamin D treatments.

New clinical trials with vitamin D and analogs in renal disease

Two new clinical trials highlight refinements in the use of vitamin D and its analogs in the treatment of secondary hyperparathyroidism in end-stage renal disease (ESRD), and the treatment of proteinuria in diabetics. In patients with ESRD, alfacalcidol is as effective as paricalcitol in suppressing parathyroid hormone; the occurrence of hypercalcemia and hyperphosphatemia is infrequent and similar with the two analogs. Oral cholecalciferol reduces albuminuria and urinary transforming growth factor-β1 in patients with type 2 diabetes mellitus and proteinuria.

Validation of a Rapid Parathyroid Hormone Assay and Intraoperative Measurement of Parathyroid Hormone in Dogs with Benign Naturally Occurring Primary Hyperparathyroidism

To (1) validate a rapid chemiluminescent parathyroid hormone (PTH) assay, (2) determine it's usefulness locating a parathyroid nodule(s), and (3) determine if >50% decrease in PTH corresponds with excision of autonomously functioning parathyroid tissue. Prospective cohort study. Dogs (n=12) with naturally occurring primary hyperparathyroidism and 25 healthy dogs. The assay was validated with linearity, precision, and intermethod comparison. Preoperative and postoperative systemic plasma PTH concentrations, measured from saphenous venous blood, were compared. Intraoperative local PTH concentrations were measured in right and left jugular venous blood before and after surgical excision of the grossly abnormal parathyroid gland(s). Within run and day-to-day precisions were acceptable (coefficient of variation <15%). Dilutional parallelism was used to demonstrate high correlation between measured and calculated PTH concentrations (R(2)=0.99). The assay methods had good correlation but numerical results of the rapid assay were usually lower than the immunoradiometric assay. Seven of 12 dogs had uniglandular disease and five had multiglandular disease. Systemic and local PTH concentrations decreased >50% in all the dogs after excision of the parathyroid gland(s). Mean preoperative systemic plasma PTH concentrations were significantly higher than mean postoperative systemic concentrations. Local PTH concentrations could not be used reliably to differentiate the side of the autonomously functioning gland(s). Hypercalcemia resolved postoperatively in all the dogs. This assay measures PTH in dogs. Rapid PTH measurement provided documentation of decreased PTH concentration after removal of autonomously functioning parathyroid tissue. Use of this assay allows documentation of a significant decrease in PTH concentration after excision of autonomously functioning parathyroid tissue.

Impact of Ergocalciferol Treatment of Vitamin D Deficiency on Serum Parathyroid Hormone Concentrations in Chronic Kidney Disease

Background: Vitamin D deficiency is highly prevalent and associated with secondary hyperparathyroidism in patients with chronic kidney disease (CKD). The Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines recommend treatment of vitamin D deficiency starting with CKD stage 3, though no data are available showing an impact on serum parathyroid hormone (PTH) concentrations. The goal of this analysis, therefore, was to determine the effect of ergocalciferol treatment on plasma PTH concentrations in vitamin D-deficient patients with stage 3 and stage 4 CKD. Methods: A prospective, nonrandomized observational analysis was conducted in an academic community hospital CKD clinic. Fifty-two patients with stage 3 or stage 4 CKD with vitamin D deficiency and elevated PTH concentrations received ergocalciferol dosed per a modified K/DOQI guidelines protocol and adjusted every 3 months. Serum PTH, 25-vitamin D, 1,25-vitamin D, calcium, phosphorus, and albumin levels were drawn at initiation of therapy and repeated every 3 months. Results: The mean 25-vitamin D levels normalized in patients with stage 3 and 4 CKD, with values of 31.6 ± 2.2 ng/ml (78.8 ± 5.49 nmol/l) and 35.4 ± 1.9 ng/ml (88.4 ± 4.74 nmol/l), respectively (p < 0.0001). A median decrease in PTH concentrations of 13.1 and 2.0% was noted in patients with stage 3 and stage 4 CKD, respectively (p = 0.041, p = nonsignificant). Conclusions: Ergocalciferol therapy is a reasonable initial therapy for vitamin D deficiency associated with elevated PTH levels in stage 3 CKD. It does not appear to have equivalent benefits in stage 4 CKD.