José-Vicente Torregrosa

Effect of cinacalcet on hypercalcemia and bone mineral density in renal transplanted patients with secondary hyperparathyroidism.

Background. Persistent secondary hyperparathyroidism (SHP) is the most frequent cause of hypercalcemia observed in approximately 10% of renal transplanted (RT) patients 1 year after surgery. Persistent SHP with hypercalcemia is an important factor of bone loss after renal transplantation. This study prospectively evaluates the effects of Cinacalcet therapy on serum calcium (SCa) and parathyroid hormone (PTH) blood levels, and basically on bone mineral density (BMD) in RT patients with persistent hyperparathyroidism. Methods. Nine RT patients (eight women, one man) with allograft function more than 6 months were included based on total SCa more than 10.5 mg/dL and intact parathyroid hormone (iPTH) concentration more than 65 pg/mL. After inclusion, patients started on a single daily oral dose of 30 mg of Cinacalcet. At inclusion and every study visit blood levels of creatinine, Ca, P, alkaline phosphatase, iPTH 1,25- dihydroxyvitamin D3, and 25-hydroxyvitamin D3 were assessed. Baseline and at the end of study radial BMD were measured. Study follow-up was 12 months. Results. During the study period, SCa decreased from 11.72±0.39 to 10.03±0.54 mg/dL (P<0.001). iPTH decreased from 308.85±120.12 to 214.66±53.75 mg/dL (P<0.05). The mean serum creatinine decreased from 1.58±0.34 to 1.25±0.27 mg/dL (P=0.03) and the mean radial BMD increased from 0.881±0.155 to 0.965±0.123 gr/cm2 (P<0.05). There were no significant changes in the other parameters assessed. One patient was excluded for gastrointestinal intolerance. Conclusions. In RT patients with hypercalcemia secondary to persistent SHP, Cinacalcet corrects hypercalcemia and PTH, simultaneously improving BMD.

99mTc-sestamibi Scintigraphy and Cell Cycle in Parathyroid Glands of Secondary Hyperparathyroidism

Double-phase parathyroid MIBI (99mTc-sestamibi) was performed in 27 patients with secondary hyperparathyroidism (SPT). Focal areas of increased uptake were scored for intensity on a three-point scale. All patients underwent subtotal parathyroidectomy (SPTx), and a total of 78 glands were removed at operation. Blood was obtained from the jugular vein before and after SPTx to measure the parathyroid hormone (PTH) levels. The volume and weight of the glands were calculated. The tissue was divided, with one aliquot being used for cell cycle analysis. The nuclei were acquired by flow cytometry and analyzed using CELLEIT software. Cell viability was assessed by flow cytometry and analyzed with LYSIS II software. Positive MIBI uptake was observed in 88.8% of patients. Focal MIBI uptake of one, two, or three glands was observed in 6, 11, and 8 patients, respectively. All patients experienced an 86% decrease in PTH blood level after SPTx compared to that before excision. A correlation was found between the volume of glands and the blood levels of intact PTH (iPTH) (r= 0.5, p < 0.05). A positive correlation was observed between MIBI uptake and the iPTH levels before SPTx (p < 0.01) and between the uptake of MIBI in the parathyroid glands and the cell cycle phases; low-grade uptake correlated with the G0 phase and higher uptake with G2+S phase (r= 7, p < 0.01). No correlation was observed between MIBI uptake and the weight of the glands. MIBI scintigraphy accurately reflects the functional status of the hyperplastic parathyroid glands: Higher uptake grades correlated with the active growth phase. MIBI uptake does not reveal parathyroid enlargement; rather, it identifies the presence of hyperfunctioning autonomous glands. SPTx and total parathyroidectomy with autografting (TPTx+A) are the most widely accepted surgical approaches for patients with SPT. Reoperation for recurrence is necessary in 6% to 15% of cases. MIBI is now considered to be the radionuclide of reference for parathyroid gland scanning, although it is widely accepted that it produces poor results when trying to detect hyperplastic glands.

A randomized study evaluating cinacalcet to treat hypercalcemia in renal transplant recipients with persistent hyperparathyroidism

Persistent hyperparathyroidism (HPT) after kidney transplantation (KTx) is associated with hypercalcemia, hypophosphatemia and abnormally high levels of parathyroid hormone (PTH). In this randomized trial, cinacalcet was compared to placebo for the treatment of hypercalcemia in adult patients with persistent HPT after KTx. Subjects were randomized 1:1 to cinacalcet or placebo with randomization stratified by baseline corrected total serum calcium levels (≤11.2 mg/dL [2.80 mmol/L] or >11.2 mg/dL [2.80 mmol/L]). The primary end point was achievement of a mean corrected total serum calcium value <10.2 mg/dL (2.55 mmol/L) during the efficacy period. The two key secondary end points were percent change in bone mineral density (BMD) at the femoral neck and absolute change in phosphorus; 78.9% cinacalcet‐ versus 3.5% placebo‐treated subjects achieved the primary end point with a difference of 75.4% (95% confidence interval [CI]: 63.8, 87.1), p < 0.001. There was no statistical difference in the percent change in BMD at the femoral neck between cinacalcet and placebo groups, p = 0.266. The difference in the change in phosphorus between the two arms was 0.45 mg/dL (95% CI: 0.26, 0.64), p < 0.001 (nominal). No new safety signals were detected. In conclusion, hypercalcemia and hypophosphatemia were effectively corrected after treatment with cinacalcet in patients with persistent HPT after KTx.

Alendronate for treatment of renal transplant patients with osteoporosis.

UNLABELLED Osteoporosis is a frequent complication after renal transplantation. Some workers have shown that bisphosphonates may be effective to prevent and treat corticosteroid-induced osteoporosis in these patients. In this study we report our experience with administration of the biphosphonate alendronate to treat renal transplanted patients with established osteoporosis. MATERIALS AND METHODS Twelve to 24 months after transplantation (9 women, 5 men) 14 renal transplant patient were treated with alendronate and 12 patients (7 women, 5 men) were untreated. All patients displayed an iPTH <240 pg/mL and a bone mineral density (BMD) t-score <-2.5. All patients received cyclosporine and prednisone therapy. Biochemical measurements, BMD, and X-rays of the lumbar spine were measured during study. Patients in the treatment group received alendronate 10 mg/d (po) and vitamin D plus calcium (800 UI cholecalciferol and 2.5 g of CaCO(3)) per day while those in the control group only received vitamin D plus calcium, at the same dose. RESULTS There was no difference in mean age, weight, time after transplantation, or immunosuppression between the treatment and control groups. There were no significant differences in the biochemical parameters during the study period. Over the 1-year study period, patients receiving alendronate displayed a greater increase in BMD. Lumbar spine BMD increased 4.3 +/- 6.1% in the treatment group versus 0.55 +/- 5.30% in controls. Femoral neck BMD increased 10.3 +/- 11.9% and 2.2 +/- 5.7%, respectively, in the treatment and control groups. Patients receiving alendronate frequently experienced intestinal disconfort. CONCLUSIONS The bisphosphonate alendronate is effective to treat renal transplant patients suffering from established osteporosis.

Effect of hemodialysis and renal failure on serum biochemical markers of bone turnover

The aim of the present study was to evaluate the effect of hemodialysis and renal failure on serum bone markers. Serum total alkaline phosphatase (TAP), procollagen type I aminoterminal propeptide (PINP), and Β-carboxyterminal telopeptide of type I collagen (Β-CTX), as well as intact parathyroid hormone (iPTH), creatinine, and total protein were measured in 14 patients with endstage renal disease (ESRD) before and at 1, 2, and 4 h during a hemodialysis session, and at the same sampling interval in 6 renal transplant recipients. The results were compared to those obtained in 20 healthy adults. All patients showed increased baseline mean values of PINP, Β-CTX, and iPTH. Β-CTX differed significantly between hemodialysis patients and renal transplant recipients. TAP and Β-CTX were the only markers which correlated with iPTH (P ≪ 0.05) and creatinine values (P ≪ 0.001), respectively. Renal transplant recipients did not show significant variations in the evolution of mean values of bone markers throughout the study, whereas, during the dialysis period, all the bone markers analyzed in the study showed a significant change. The change differed depending on the marker considered: Β-CTX showed a significant decrease at the end of the session, TAP increased at this time and, although PINP showed an initial increase during hemodialysis, no significant changes were observed at the end of the session. We conclude that bone markers are significantly influenced by hemodialysis, especially serum TAP and Β-CTX. ESRD is associated with an increase in these bone markers, in some cases related to iPTH values and in others to glomerular function. These findings should be taken into account when evaluating bone markers in these patients.

Open-Label Trial: Effect of Weekly Risedronate Immediately After Transplantation in Kidney Recipients

Background. Treatment with oral risedronate to prevent bone mineral density (BMD) loss in renal transplant recipients has been shown to be effective. There is no agreement on the optimum moment of introduction or how long it should be continued. The aim was to evaluate the effectiveness of risedronate at doses of 35 mg/week in renal transplant recipients who underwent treatment immediately after transplant. Methods. A randomized clinical trial was performed on 101 renal transplant patients. The study group (52 patients) received 35 mg risedronate weekly, vitamin D, and calcium, whereas the control group (49 patients) received only vitamin D and calcium. At baseline, 3, 6, and 12 months, basic biochemistry and mineral bone metabolic parameters were determined. Vertebra and hip fracture assessment was performed by means of x-ray and DEXA; an intention-to-treat analysis was performed. Results. Patients in control group showed a significant worsening of BMD (P<0.05) 12 months into the study. At all follow-up points, lumbar BMD of the study group was significantly greater (P<0.05), whereas femoral BMD of those treated with risedronate was only significant at 6-month follow-up (P<0.05). There was a trend of more vascular calcifications and fractures in the control group, but this was not statistically significant. Conclusion. Weekly oral administration of risedronate immediately after renal transplantation contributes to an improved BMD, particularly in the femoral neck at 6-month follow-up, without major side effects. Long-term follow-up is needed to establish whether oral risedronate has an influence on vascular calcifications and bone fractures.

Evolution of Secondary Hyperparathyroidism After Kidney Transplantation in Patients Receiving Cinacalcet on Dialysis

BACKGROUND Secondary hyperparathyroidism (SHPT) is a relevant problem in patients undergoing dialysis, and cinacalcet hydrochloride seems to be the best option for controlling it. After kidney transplantation (KTx), moderate to severe SHPT may persist and cause hypercalcemia and hypophosphatemia, among other deleterious effects. The number of patients receiving cinacalcet before KTx is increasing. OBJECTIVE To evaluate the evolution of calcemia, phosphatemia, and intact parathyroid hormone (iPTH) after KTx in patients with SHPT receiving cinacalcet on dialysis. PATIENTS AND METHODS The study included 19 patients (15 men and 4 women; mean [SD] age, 52 [13] years) undergoing dialysis and receiving cinacalcet before KTx. Mean duration of dialysis before KTx was 33 (25) months, and cinacalcet dose was 45 (15) mg/d. Creatinine, calcium, phosphorus, alkaline phosphatase, and iPTH concentrations were evaluated at baseline (day of surgery), at 15 days after surgery, and then monthly for 6 months. In all patients, cinacalcet therapy was discontinued on the day of surgery. RESULTS After the first month post-KTx, mean (SD) serum creatinine concentration was 1.6 (0.4) mg/dL and remained stable during follow-up. Calcium and phosphorus concentrations were normal in 13 patients after KTx; however, in 6 patients, hypercalcemia (calcium concentration, 11 [1.3] mg/dL) or hypophosphatemia (phosphorus concentration, 1.7 [0.6] mg/dL) developed, with iPTH concentration of 557 (400) pg/mL and alkaline phosphatase concentration of 307 (114) IU/mL. Treatment with cinacalcet resulted in correction of calcium and phosphorus concentrations (10.1 [0.4] mg/dL and 1.7 [0.7] mg/dL, respectively). Patients in whom hypercalcemia or hypophosphatemia developed were receiving cinacalcet, 60 mg/d or more, during dialysis therapy. Patients who received cinacalcet, 30 mg/d, before KTx did not exhibit hypercalcemia or hypophosphatemia after KTx. CONCLUSION In patients with HPT undergoing dialysis and receiving cinacalcet, 60 mg/d or more, this drug therapy should be continued after KTx to avert development of hypercalcemia or hypophosphatemia.

Renal transplantation in a C-ANCA(+) patient with Behcet disease and rapidly progressive glomerulonephritis

Behcets disease (BD) is a chronic, relapsing, inflammatory disorder, and the underlying histophatological lesion is vasculitis of unknown cause. Some case reports of BD with positive C-ANCA titers have been reported, but only 2 case reports have documented the association of ANCA-associated glomerulonephritis (GN) and BD, and no renal transplantation cases have been described. We report such a case. A 27-year-old male was referred for consultation due to acute renal failure. Seven years before, BD was diagnosed. At the time of consultation he suffered from uveitis and generalized arthralgias. The serum creatinine was 14 mg/dl and urinalysis showed 4+ protein and microscopic hematuria. Results of serological tests were normal. The ANCA PR 3 titer was 1:100 of cytoplasmic pattern. A renal biopsy showed a rapidly progressive type III glomerulonephritis. In spite of immunosuppressive therapy with cyclophosphamide and high steroid doses, renal function did not recover and hemodialysis therapy was initiated. One year later, the patient underwent a renal transplantation. Follow-up was absolutely normal, and 5 years after transplantation, renal function persisted to be normal, without urinary abnormalities and signs of reactivation of original disease, except for occasional arthralgias. C-ANCA titer was decreased and remained stable (<1:30). He is now receiving maintenance immunosupression with cyclosporin and prednisone. This report shows the long-term successful renal transplantation in a patient with ANCA-associated glomerulonephritis and BD. The success of renal transplant in BD with renal involvement is encouraging and should be pursued.

Economic Analysis of the Treatment of End-stage Renal Disease Treatment: Living-donor Kidney Transplantation Versus Hemodialysis

INTRODUCTION End-stage renal disease (ESRD) is a major public health problem in the Spanish health system. Kidney transplantation is the treatment of choice, offering better survival and cost-effectiveness than other alternatives. This study aimed to compare the cost of living-donor kidney transplantation (LDKT) during the first year after transplantation with that of hemodialysis (HD). METHOD A prospective, descriptive study of cost and efficacy was performed in the Hospital Clinic in Barcelona from January to December 2011. We included 106 patients (57 undergoing HD and 49 receiving a LDKT). The costs of LDKT (donor and recipient) and HD were calculated based on our economic database program. RESULTS The mean age of recipients and donors was 46 ± 15 and 52 ± 10 years, respectively, and 67% of the recipients were men. In HD patients, the mean age was 67 ± 11 years and 62% were men. The total cost of LDKT was €29,897.91 (€8,128.44 for donors and €21,769.47 for recipients). The total cost of HD was €43,000.88 (€37,917 for HD and related procedures plus €5,082 for transport). LDKT represented a savings of €13,102.97 per patient/year and the payback period was less than 1 year. Quality-adjusted life years were higher in LDKT than in HD patients. CONCLUSION LDKT is cost effective during the first year after transplantation and is associated with enhanced quality of life. From both the medical and economic points of view, pre-emptive LDKD should be encouraged in Spain to reduce the health budget for ESRD.

Blueprint for a European calciphylaxis registry initiative: the European Calciphylaxis Network (EuCalNet).

Calcific uraemic arteriolopathy (CUA) is a rare disease and continues to be a clinical challenge. The typical course of CUA is characterized by painful skin discolouration and induration evolving to necrotic ulcerations. Medial calcification of cutaneous arterioles and extensive extracellular matrix remodelling are the hallmarks of CUA. The epidemiology and risk factors associated with this disease are still not fully understood. Moreover, CUA treatment strategies vary significantly among centres and expert recommendations are heterogeneous. Registries may provide important insights and information to increase our knowledge about epidemiology and clinical aspects of CUA and may help to optimize its therapeutic management. In 2006, we established an internet-based registry in Germany (www.calciphylaxie.de) to allow online notification of patients with established or suspected CUA. The registry includes a comprehensive database with questions covering >70 parameters and items regarding patient-related and laboratory data, clinical background and presentation as well as therapeutic strategies. The next phase will be to allow international patient registration via www.calciphylaxis.net as part of the multinational EuCalNet (European Calciphylaxis Network) initiative, which is supported by the ERA-EDTA scientific working group ‘CKD-MBD’. Based on the valuable experience with the previous German CUA registry, EuCalNet will be a useful tool to collect data on the rare disease CUA and may become a basis for prospective controlled trials in the near future.