Renal complications and quality of life in postsurgical hypoparathyroidism: a case-control study.

PURPOSE: Conventional therapy (calcium and activated vitamin D) does not restore calcium homeostasis in patients with chronic hypoparathyroidism (HypoPT) and is associated with renal complications and reduced quality of life (QoL). The aim of this study was to evaluate in a case-control, cross-sectional study, the rate of renal complications and QoL in two sex- and age-matched cohort of patients with differentiated thyroid cancer with (n = 89) and without (n = 89) chronic post-operative HypoPT (PoHypoPT) and their relationship with the biochemical control of the disease. METHODS: Serum and urinary parameters, renal ultrasound and QoL were assessed by SF-36 and WHO-5 questionnaires. RESULTS: Forty-three (48.3%) PoHypoPT patients reported symptoms of hypocalcemia. Twenty-six (29.2%) patients were at target for all 6 parameters, 46 (51.6%) for 5. The most frequently unmet targets were gender-specific 24-h urinary calcium (44.9%) and serum calcium (37.1%). Serum phosphate, magnesium and 25(OH)D were in the normal range in > 90% of patients. Renal calcifications were found in 26 (29.2%) patients, with no correlation with 24-h urinary calcium. eGFR did not differ between patients and controls. Conversely, patients had a significant higher rate of renal calcifications and a lower SF-36, but not WHO-5, scores. SF-36 scores did not differ between PoHypoPT patients who were, or not, hypocalcemic. CONCLUSIONS: Our study shows that the rate of renal calcifications was higher in patients with PoHypoPT than in those without. This finding, together with the reduced QoL and the presence of hypocalcemic symptoms in about half patients, underscores that the treatment of chronic HypoPT with conventional therapy is suboptimal.

Dispelling myths and misconceptions about the treatment of acute hyperkalemia.

Hyperkalemia represents a widespread and potentially lethal condition that affects millions of people across their lives. Despite the prevalence and severity of the condition, there are no consensus guidelines on the treatment of hyperkalemia or even a standard definition. Herein, we provide a succinct review of what we believe to be the most significant misconceptions encountered in the emergency care of hyperkalemia, examine current available literature, and discuss practical points on several modalities of hyperkalemia treatment. Additionally, we review the pathophysiology of the electrocardiographic effects of hyperkalemia and how intravenous calcium preparations can antagonize these effects. We conclude each section with recommendations to aid emergency physicians in making safe and efficacious choices for the treatment of acute hyperkalemia.

A randomised controlled trial to examine the effects of cinacalcet on bone and cardiovascular parameters in haemodialysis patients with advanced secondary hyperparathyroidism.

BACKGROUND: Secondary hyperparathyroidism may lead to increased cardiovascular risk. The use of cinacalcet may improve bone and cardiovascular health with improved parathormone (PTH) and phosphate control. METHODS: This is an open-label prospective randomised controlled trial to compare progression of cardiovascular and chronic kidney disease mineral and bone disorder (CKD-MBD) parameters. Patients were randomised to receive cinacalcet alongside standard therapy or standard therapy alone. Thirty-six haemodialysis patients who had > 90 days on dialysis, iPTH > 300 pg/mL, calcium > 2.1 mmol/L and age 18-75 years were included. Following randomization, all 36 patients underwent an intensive 12-week period of bone disease management aiming for iPTH 150-300 pg/mL. The primary outcome was change in vascular calcification using CT agatston score. Secondary outcomes included pulse wave velocity (PWV), left ventricular mass index (LVMI), carotid intima-media thickness (CIMT), augmentation index (Aix) and bone measurements. The above measurements were obtained at baseline and 12 months. RESULTS: There was no evidence of a group difference in the progression of calcification (median change (IQR) cinacalcet: 488 (0 to1539); standard therapy: 563 (50 to 1214)). In a post hoc analysis combining groups there was a mean (SD) phosphate reduction of 0.3 mmol/L (0.7) and median (IQR) iPTH reduction of 380 pg/mL (- 754, 120). Regression of LVMI and CIMT was seen (P = 0.03 and P = 0.001) and was significantly associated with change of phosphate on multi-factorial analyses. CONCLUSIONS: With a policy of intense CKD-MBD parameter control, no significant benefit in bone and cardiovascular markers was seen with the addition of cinacalcet to standard therapy over one year. Tight control of hyperphosphataemia and secondary hyperparathyroidism may lead to a reduction in LVMI and CIMT but this needs further investigation. Although the sample size was small, meticulous trial supervision resulted in very few protocol deviations with therapy.

The Development of Molecular Biology of Osteoporosis.

Osteoporosis is one of the major bone disorders that affects both women and men, and causes bone deterioration and bone strength. Bone remodeling maintains bone mass and mineral homeostasis through the balanced action of osteoblasts and osteoclasts, which are responsible for bone formation and bone resorption, respectively. The imbalance in bone remodeling is known to be the main cause of osteoporosis. The imbalance can be the result of the action of various molecules produced by one bone cell that acts on other bone cells and influence cell activity. The understanding of the effect of these molecules on bone can help identify new targets and therapeutics to prevent and treat bone disorders. In this article, we have focused on molecules that are produced by osteoblasts, osteocytes, and osteoclasts and their mechanism of action on these cells. We have also summarized the different pharmacological osteoporosis treatments that target different molecular aspects of these bone cells to minimize osteoporosis.

Regulatory T cells are expanded by Teriparatide treatment in humans and mediate intermittent PTH-induced bone anabolism in mice.

Teriparatide is a bone anabolic treatment for osteoporosis, modeled in animals by intermittent PTH (iPTH) administration, but the cellular and molecular mechanisms of action of iPTH are largely unknown. Here, we show that Teriparatide and iPTH cause a ~two-threefold increase in the number of regulatory T cells (Tregs) in humans and mice. Attesting in vivo relevance, blockade of the Treg increase in mice prevents the increase in bone formation and trabecular bone volume and structure induced by iPTH Therefore, increasing the number of Tregs is a pivotal mechanism by which iPTH exerts its bone anabolic activity. Increasing Tregs pharmacologically may represent a novel bone anabolic therapy, while iPTH-induced Treg increase may find applications in inflammatory conditions and transplant medicine.

Case report of a cystic parathyroidal adenoma with rapid growth induced by cinacalcet.

BACKGROUND: Primary hyperparathyroidism is a rare condition of disease which can seldomly present as giant retrotrhyroideal cysts, complicating the localization of the adenoma to resect. CASE PRESENTATION: A 56-year old female presented with hypercalcaemia of 3.38 mmol/L (2.2-2.65 mmol/L) and a history of breast cancer. A fast growing cystic parathyroidal adenoma was diagnosed by a multimodal approach including comprehensive diagnostic imaging (ultrasonography, scintigraphies, dynamic MRI) and cytopathological investigations after ultrasonography-guided puncture. The patient was cured by surgical extraction of the whole adenoma. In retrospect, the rapid growth was most likely induced by cinacalcet (initially 30 mg/d, later 60 mg/d) therapy which the patient received for few months only. Primary hyperparathyroidism was ascertained because surgical removal of the solitary adenoma cured the patient. Furthermore, there was no relevant renal insufficiency or history of prolonged calcium-level deregulation. CONCLUSIONS: This phenomenon of cystic degeneration of parathyroidal adenoma under therapy with cinacalcet has previously been described in secondary hyperparathyroidism, but not in primary hyperparathyroidism and should be considered in diagnostic approach.

Effect of Cinacalcet on the Redox Status of Albumin in Secondary Hyperparathyroidism Patients Receiving Hemodialysis.

Chronic kidney disease (CKD) patients with secondary hyperparathyroidism (SHPT) have an increased risk of cardiovascular disease (CVD). Cinacalcet is a calcimimetic that permits impaired endothelial functions to be recovered via inhibiting parathyroid hormone (PTH) production in SHPT patients. However, the underlying mechanism for its action remains unknown. The purpose of this study was to examine the effect of cinacalcet on the redox state of human serum albumin (HSA), a reliable marker for assessing endothelial oxidative damage in SHPT patients who were receiving hemodialysis. Cinacalcet was administered to six SHPT patients for a period of 8 weeks. After 4 weeks of treatment, cinacalcet significantly decreased the oxidized albumin ratio which is a ratio of reduced and oxidized forms of HSA via increasing reduced form of HSA. Moreover, the radical scavenging abilities of HSA that was isolated from SHPT patients were increased by cinacalcet, suggesting the recovery of the impaired vascular anti-oxidant ability. Interestingly, the oxidized albumin ratio in SHPT patients was significantly higher than that in hemodialysis patients. In addition, the changes of intact PTH levels were significantly correlated with the oxidized albumin ratio. It therefore appears that PTH may induce oxidative stress in SHPT patients. In fact, an active analogue of PTH increased the production of reactive oxygen species in human endothelial cells. Thus, cinacalcet exhibits anti-oxidative activity through its pharmacological action. Additionally, cinacalcet itself showed radical scavenging activity. In conclusion, cinacalcet improves the redox status of HSA by inhibiting PTH production and partially by its radical scavenging action.

Efficacy and safety of cinacalcet compared with other treatments for secondary hyperparathyroidism in patients with chronic kidney disease or end-stage renal disease: a meta-analysis.

BACKGROUND: It is controversial for the effect and safety between cinacalcet and other treatments in treating secondary hyperparathyroidism for patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD). METHODS: Embase, PubMed, and Cochrane Library were searched through Feb 2017. 21 randomized controlled trials were included. We calculated the pooled mean difference (MD), relative risk (RR) and corresponding 95% confidence interval (CI). RESULT: Patients received calcimimetic agents had significantly decreased serum parathyroid hormone (MD = - 259.24 pg/mL, 95% CI: - 336.23 to - 182.25), calcium (MD = - 0.92 mg/dL, 95% CI: - 0.98 to - 0.85) and calcium phosphorus product (MD = - 5.97 mg2/dL2, 95% CI: - 9.77 to - 2.16) concentration compared with control treatment. However, the differences in cardiovascular mortality and all-cause mortality between calcimimetics agents and control group were not statistically significant. The incidence of nausea (RR = 2.13, 95% CI: 1.62 to 2.79), vomiting (RR = 1.99, 95% CI: 1.78 to 2.23) and hypocalcemia (RR = 10.10, 95% CI: 7.60 to 13.43) in CKD patients with calcimimetics agents was significantly higher than that with control treatment. CONCLUSION: Cinacalcet improved the biochemical parameters in CKD patients, but did not improve all-cause mortality and cardiovascular mortality. Moreover, cinacalcet can cause some adverse events.

Factors affecting the relationship between ionized and corrected calcium levels in peritoneal dialysis patients: a retrospective cross-sectional study.

BACKGROUND: Chronic kidney disease-mineral and bone disorder (CKD-MBD) management in patients with end-stage renal disease is important owing to the risk of cardiovascular diseases. In clinical practice, we manage patients not by monitoring the levels of biologically active ionized calcium (iCa) but by monitoring total serum calcium or corrected calcium (cCa). We previously reported that iCa/cCa ratio was different between patients with hemodialysis and those with peritoneal dialysis (PD). In PD patients, several factors are expected to affect iCa/cCa ratio. Therefore, modifying the strategy to achieve better CKD-MBD management might be necessary; however, no reports have studied this to date. Therefore, we investigated the factors influencing iCa/cCa ratio in PD patients. METHODS: This retrospective cross-sectional study examined background and laboratory data, including iCa, collected at routine outpatient visits. The patients were divided into the first, second, and third tertile of iCa/cCa ratio groups to compare patient background and laboratory data. Multiple regression analysis was used to investigate the factors influencing iCa/cCa ratio. We used multiple imputation to deal with missing covariate data. RESULTS: In total, 169 PD patients were enrolled. In PD patients with lower iCa/cCa ratio, PD duration was longer and pH was higher. Urine volume and weekly renal Kt/V were lower in the patients with lower iCa/cCa ratio than in those with higher iCa/cCa ratio. iCa/cCa ratio and weekly renal Kt/V were directly correlated (r = 0.41, p < 0.01), and weekly renal Kt/V and pH were independent factors affecting iCa/cCa ratio (t = 2.86, p < 0.01 and t = - 5.42, p < 0.01, respectively). CONCLUSIONS: iCa levels were lower in PD patients with lower residual renal function (RRF) even though their cCa levels were equal to those with maintained RRF, warranting caution in the assessment and management of CKD-MBD in PD patients.

Changes to bone mineral density, the trabecular bone score and hip structural analysis following parathyroidectomy: a case report.

BACKGROUND: Reduction in bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) occurs in secondary hyperparathyroidism associated with chronic kidney disease. BMD generally increases following parathyroidectomy, however longitudinal changes to other DXA-derived parameters, the trabecular bone score (TBS) and hip structural analysis (HSA), have not been described. Postoperative calcium requirements and positive calcium balance raise concerns for an increased risk of vascular calcification. This case illustrates the dramatic increase in BMD that can follow parathyroidectomy in a patient on dialysis, and for the first time demonstrates improvements to HSA parameters and to the TBS. CASE PRESENTATION: A 30-year old woman on haemodialysis underwent subtotal parathyroidectomy for secondary hyperparathyroidism. She developed a post-operative 'hungry bone syndrome' requiring substantial calcium and calcitriol supplementation. Six months post-parathyroidectomy, BMD increased by 42% at the lumbar spine, 30% at the femoral neck and 25% at the total proximal femur, with increases sustained over the following 18 months. The TBS increased by 8%. HSA showed a 63% increase in femoral neck cortical thickness and 38% reduction in the buckling ratio, consistent with increased femoral neck stability. The abdominal aortic vascular calcification score (0-24) increased from zero 8-years pre-parathyroidectomy to 2/24 at 18-months post-parathyroidectomy. CONCLUSION: BMD losses incurred by secondary hyperparathyroidism recover rapidly after parathyroidectomy, particularly at sites of trabecular bone. Bone architectural parameters, measured as the TBS and by HSA, also improve. Greater BMD gains may be associated with higher post-operative calcium requirements. While bone is the major reservoir for post-parathyroidectomy calcium supplementation, positive calcium balance may contribute to vascular calcification risk.

Delayed-Union of Acetabular Stress Fracture in Female Gymnast: Use of Teriparatide to Augment Healing.

Pelvic stress fractures are rare and present unique challenges for medical personnel. Delayed healing can lead to increased physical, psychological, and social stress for athletes. Recent literature suggests effective use of a synthetic derivative of parathyroid hormone, teriparatide, to augment healing of delayed-union stress fractures. We present a case of a female National Collegiate Athletic Association Division I gymnast successfully returned to play after a 12-week course of teriparatide injections for an ischioacetabular stress fracture.

Molecular Mechanisms and Emerging Therapeutics for Osteoporosis.

Osteoporosis is the most common chronic metabolic bone disease. It has been estimated that more than 10 million people in the United States and 200 million men and women worldwide have osteoporosis. Given that the aging population is rapidly increasing in many countries, osteoporosis could become a global challenge with an impact on the quality of life of the affected individuals. Osteoporosis can be defined as a condition characterized by low bone density and increased risk of fractures due to the deterioration of the bone architecture. Thus, the major goal of treatment is to reduce the risk for fractures. There are several treatment options, mostly medications that can control disease progression in risk groups, such as postmenopausal women and elderly men. Recent studies on the basic molecular mechanisms and clinical implications of osteoporosis have identified novel therapeutic targets. Emerging therapies targeting novel disease mechanisms could provide powerful approaches for osteoporosis management in the future. Here, we review the etiology of osteoporosis and the molecular mechanism of bone remodeling, present current pharmacological options, and discuss emerging therapies targeting novel mechanisms, investigational treatments, and new promising therapeutic approaches.

Current Evidence and Future Perspectives on Pharmacological Treatment of Calcific Aortic Valve Stenosis.

Calcific aortic valve stenosis (CAVS), the most common heart valve disease, is characterized by the slow progressive fibro-calcific remodeling of the valve leaflets, leading to progressive obstruction to the blood flow. CAVS is an increasing health care burden and the development of an effective medical treatment is a major medical need. To date, no effective pharmacological therapies have proven to halt or delay its progression to the severe symptomatic stage and aortic valve replacement represents the only available option to improve clinical outcomes and to increase survival. In the present report, the current knowledge and latest advances in the medical management of patients with CAVS are summarized, placing emphasis on lipid-lowering agents, vasoactive drugs, and anti-calcific treatments. In addition, novel potential therapeutic targets recently identified and currently under investigation are reported.

Mild primary hyperparathyroidism-to treat or not to treat?

INTRODUCTION: The presentation of primary hyperparathyroidism (PHPT) has shifted from a disease characterized by renal and skeletal complications to a mild or asymptomatic condition. Modern imaging allows localization of a surgical target in the majority of cases. SOURCES OF DATA: Data were collected from literature searches of online databases including PUBMED, MEDLINE and Cochrane. A narrative review was performed. AREAS OF AGREEMENT: Parathyroidectomy is the only therapy with curative potential with good outcomes and low risk of complications in experienced hands. Current guidelines advocate that surgery is offered in all symptomatic cases and in those who meet criteria depending on age, serum calcium concentration, skeletal and renal parameters. A structured monitoring approach should be offered to those who do not undergo surgery. AREAS OF CONTROVERSY: Thresholds for intervention to improve skeletal and renal outcomes are debatable. In addition, controversy persists over the benefit of surgery for non-skeletal/renal outcomes. GROWING POINTS: The role of medical management of PHPT using agents such as bisphosphonates, denosumab and cinacalcet are discussed. AREAS TIMELY FOR DEVELOPING RESEARCH: In summary, further data on the natural history and effects of treatment of mild and asymptomatic PHPT are required to determine thresholds for surgery. In particular, further investigations of non-skeletal and non-renal parameters, such as neurocognitive quality of life and cardiovascular disease are required. Data on normocalcaemic PHPT are lacking. Large-scale randomized controlled trials would be welcome in these areas, however in view of the cost implications a more pragmatic approach may be to develop collaborative multi-centre registries.

High-dose preoperative cholecalciferol to prevent post-thyroidectomy hypocalcaemia: A randomized, double-blinded placebo-controlled trial.

OBJECTIVE: Post-thyroidectomy hypocalcaemia is a significant cause of morbidity and prolonged hospitalization, usually due to transient parathyroid gland damage, treated with calcium and vitamin D supplementation. We present a randomized, double-blinded placebo-controlled trial of preoperative loading with high-dose cholecalciferol (300 000 IU) to reduce post-thyroidectomy hypocalcaemia. PATIENTS AND MEASUREMENTS: Patients (n = 160) presenting for thyroidectomy at tertiary hospitals were randomized 1:1 to cholecalciferol (300 000 IU) or placebo 7 days prior to thyroidectomy. Ten patients withdrew prior to surgery. The primary outcome was post-operative hypocalcaemia (corrected calcium <2.1 mmol/L in first 180 days). RESULTS: The study included 150 patients undergoing thyroidectomy for Graves' disease (31%), malignancy (20%) and goitre (49%). Mean pre-enrolment vitamin D was 72 ± 26 nmol/L. Postoperative hypocalcaemia occurred in 21/72 (29%) assigned to cholecalciferol and 30/78 (38%) participants assigned to placebo (P = 0.23). There were no differences in secondary end-points between groups. In pre-specified stratification, baseline vitamin D status did not predict hypocalcaemia, although most individuals were vitamin D replete at baseline. Post-hoc stratification by day 1 parathyroid hormone (PTH) (<10 pg/mL, low vs ≥10 pg/mL, normal) was explored due to highly divergent rates of hypocalcaemia in these groups. Using a Cox regression model, the hazard ratio for hypocalcaemia in the cholecalciferol group was 0.56 (95%CI 0.32-0.98, P = 0.04) after stratification for Day 1 PTH. Further clinical benefits were observed in these subgroups. CONCLUSIONS: Pre-thyroidectomy treatment with high-dose cholecalciferol did not reduce the overall rate of hypocalcaemia following thyroidectomy. In subgroups stratified by day 1 PTH status, improved clinical outcomes were noted.

Efficacy and safety of elcatonin in postmenopausal women with osteoporosis: a systematic review with network meta-analysis of randomized clinical trials.

The present systematic review aimed to evaluate bone mineral density (BMD) change and complication rates of elcatonin on treating postmenopausal osteoporosis. The result confirmed efficacy of elcatonin and safety in combination therapies of elcatonin (C-E). INTRODUCTION: Postmenopausal osteoporosis is an important issue in global aging trends. One treatment of osteoporosis is elcatonin, a kind of calcitonin. However, it has been challenged for long time because of safety. Many trials investigated on this topic, but they were designed differently. Those designs can be categorized in monotherapy of elcatonin (M-E) and C-E. Unfortunately, no synthesized evidence dealt this topic. METHODS: This study systematically identified target trials from six important databases and only included randomized controlled trial for synthesis. Two investigators assessed quality of eligible trials using the Cochrane Risk of Bias Tool, and they independently extracted data. Network meta-analysis performed Peto odds ratio (POR, used for dealing with zero cell) or weighted mean difference (WMD, for continuous data) with 95% confidence intervals (CI) and consistency H. RESULTS: Sixteen trials recruiting 2754 women with postmenopausal osteoporosis were included in our study. Elcatonin therapies and non-elcatonin medications had comparable fracture rates and bone mineral density change. Yet, C-E (WMD, - 18.93; 95% CI, - 23.97 to - 13.89) and M-E (WMD, - 13.72; 95% CI, - 19.51 to - 7.94) had significantly lower pain score than non-elcatonin medications. However, M-E (POR = 8.413, 95% CI, 2.031 to 34.859) and non-elcatonin medication (Peto OR, 7.450; 95% CI, 1.479 to 37.530) had significantly higher complication rates than placebo. No evidence detected inconsistency and small study effect in this network model. CONCLUSIONS: Based on current evidence, C-E may be considered for treating postmenopausal osteoporosis because it benefits on pain relief and complications. Moreover, it shows comparable fracture rate and bone mineral density change as compared with anti-osteoporosis and calcium supplements. Nevertheless, further trials are needed to investigate formula and dosages of elcatonin.

Mutation update and long-term outcome after treatment with active vitamin D3 in Chinese patients with pseudovitamin D-deficiency rickets (PDDR).

Pseudovitamin D-deficiency rickets is a rare disease which is caused by CYP27B1. In this study, we identified 9 mutations in 7 PDDR patients. In addition, we observed the response to long-term treatment of calcitriol in 15 Chinese patients with PDDR, which showed that the biochemical abnormalities had been corrected satisfactorily after 1-year treatment. INTRODUCTION: Pseudovitamin D-deficiency rickets is a rare autosomal recessive disorder resulting from a defect in 25-hydroxyvitamin D 1α-hydroxylase, which is encoded by CYP27B1. The purpose of this study was to identify the CYP27B1 mutations and investigate the response to long-term treatment of calcitriol in Chinese patients with PDDR. METHODS: We investigated CYP27B1 mutations in seven individuals from six separate families. To investigate the response to long-term (13 years) treatment with calcitriol in PDDR patients, we additionally collected clinical data of eight families from our previous report and analyzed their biochemical parameter and radiographic changes during the treatment. RESULTS: Nine different mutations were identified: two novel missense mutations (G194R, R259L), three novel and one reported deletion mutations (c1442delA, c1504delA, c311-321del, and c. 48-60del), two novel nonsense mutations (c.85G>T, c.580G>T), and a reported insertion mutation (c1325-1332insCCCACCC). The statistical analysis revealed that parathyroid hormone (PTH) and ALP significantly decreased after 6-month and 1-year treatment with calcitriol respectively. Urine calcium was measured in all the patients without kidney stones being documented. After 6-year treatment, the radiographic abnormalities had also been improved. Two patients who had reached their final height are both with short stature (height Z-score below - 2.0). CONCLUSIONS: We identified seven novel mutations of CYP27B1 gene in seven Chinese PDDR families. Our findings revealed after 1-year treatment of active vitamin D3, PTH and ALP significantly decreased. The correction of the biochemical abnormalities had not improved the final height satisfactorily.

Cinacalcet sustainedly prevents pancreatitis in a child with a compound heterozygous SPINK1/AP2S1 mutation.

Familial hypocalciuric hypercalcemia is an autosomal dominant genetic disorder characterized by hypercalcemia associated with inappropriate hypocalciuria and normal parathyroid hormone levels. Acute recurrent pancreatitis (ARP) is rare in children. Predisposing factors include hypercalcemia and mutations in the serine protease inhibitor Kazal-type 1 (SPINK1) gene. The disease carries a heavy morbidity and preventive treatment options are scant. Here, we report a child with a novel genetic/metabolic form of ARP associated with compound heterozygous SPINK1/AP2S1 (adaptor protein-2 σ1-subunit) mutations, recurrence of which was completely abrogated for 6 years by cinacalcet treatment.

Successful management of tertiary hyperparathyroidism associated with hypophosphataemic rickets in an adult.

Tertiary hyperparathyroidism (THP) is a rare complication in patients with hypophosphataemic rickets (HR), usually related to long-term management with active vitamin D analogues and oral phosphate salts. If left untreated, THP may aggravate bone and renal disease. We report a case of THP, which developed during the course of HR. Preoperatively, cinacalcet administration along with gradual increase in alphacalcidol dose, led to almost normalization of serum calcium and decrease in parathyroid hormone (PTH) concentrations. The patient underwent an uneventful subtotal parathyroidectomy, resulting in PTH normalization and stabilization of eucalcaemia during 18 months of follow-up. We conclude that, except for optimal dosage of elementary phosphate and alphacalcidol, cinacalcet prior to parathyroidectomy may be an effective option in patients with HR complicated with THP.