Sternal instability in a hemodialysis patient with secondary hyperparathyroidism

A 77‐year‐old man, 11 years under chronic hemodialysis treatment for chronic renal failure of unknown origin, presented with anterior chest pain, dyspnea with paradoxical breathing, and sternal instability after a simple fall from a standing height. Patient underwent three‐vessel coronary artery bypass grafting 31 months ago. Computed tomography with three‐dimensional volume rendering showed sternal nonunion with a great gap between the two halves of the sternum and at least one fracture in the left half of the sternum. A successful surgical repair followed. Patient suffered from severe secondary hyperparathyroidism for many years. Despite treatment with sevelamer, paricalcitol and cinacalcet, intact parathyroid hormone was 1682 pg/mL. During the last 5 years, serum intact parathyroid hormone remained steadily above 1000 pg/mL. Patient refused parathyroidectomy in the past. We assume that long‐lasting severe hyperparathyroidism contributed to this rare and life‐threatening complication of median sternotomy in our patient, due to the detrimental effect of hyperparathyroidism on bone metabolism and its association with increased incidence of bone fractures and defect in bone fracture healing.     

Switch from calcitriol to paricalcitol in secondary hyperparathyroidism of hemodialysis patients: Responsiveness is related to parathyroid gland size

Paricalcitol is more effective than calcitriol in hemodialysis patients (HD) with secondary hyperparathyroidism (SHPT), but it is not effective in some of them. We have investigated the relationship between paricalcitol responsiveness and parathyroid gland (PTG) size. Thirty HD with SHPT treated previously with calcitriol for at least 6 months were switched to paricalcitol (1:4 conversion ratio). Parathyroid gland number and size (maximum longitudinal diameter [MLD] of largest PTG) was measured by ultrasonography. Patients were divided into 2 groups: group A (MLD ≤9.0 mm [17 HD]); and group B (MLD >9.0 mm [13 HD]). They were defined responder if both the last 2 monthly determinations of inhibit parathyroid hormone (iPTH) were within the target (<300 pg/mL) according to National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommendations. Twenty‐six and 20 HD completed 6‐month and 12‐month paricalcitol therapy, respectively. After 6 months of paricalcitol treatment, 23.5% HD of group A and 7.7% of group B were responders. At 12 months, 41.2 % of group A and 7.7% of group B were responders. Throughout paricalcitol therapy, serum calcium and phosphorus concentrations slightly increased in all HD but more significantly in group B. The baseline iPTH and MLD of the largest PTG were significantly correlated with final iPTH levels. Paricalcitol is more effective than calcitriol in SHPT, but the responsiveness to paricalcitol and hypercalcemia are related to PTG size. The measurement of MLD by ultrasonography may be useful for predicting responsiveness to paricalcitol, avoiding an unnecessary and expensive therapy.     

Efficacy and safety of Cinacalcet on secondary hyperparathyroidism in Chinese chronic kidney disease patients receiving hemodialysis

Introduction Secondary hyperparathyroidism (SHPT) develops in patients with chronic renal failure. Cinacalcet hydrochloride has been used successfully in U.S., Europe, and Japan in the treatment of SHPT, while maintaining serum levels of calcium and phosphorus. The efficacy and safety profile of Cinacalcet treatment vs. conventional treatments has been of great interest in clinical practice. In this recent phase III study conducted in China, efficacy and safety of a calcimimetic agent, Cinacalcet (Kyowa Hakko Kirin Co., Ltd.), were assessed for SHPT treatment in stable chronic renal disease patients on hemodialysis. Methods In this double‐blind, multicenter, placebo‐controlled, randomized phase III study, 238 subjects were enrolled in 12 centers and randomly divided into a Cinacalcet group and a placebo group. The percentage of patients achieving a serum parathyroid hormone (PTH) level ≤250 pg/mL was the primary efficacy end point. Serum calcium and phosphorus levels were measured. Adverse events and serious adverse events were recorded, and causal analysis performed. Findings In primary analysis, 25.4% of the Cinacalcet group and 3.5% of the placebo group achieved the primary end point (PTH ≤250 pg/mL). Calcium and phosphorus levels and calcium–phosphorus product were lower in the Cinacalcet group compared with the placebo group. Eleven serious adverse events were reported and considered to be not related to study drugs. Mild to moderate hypocalcemia and reduced calcium levels were reported and considered to be Cinacalcet related. Discussion This phase III study demonstrated that Cinacalcet is effective and well tolerated in treating SHPT in Chinese chronic kidney disease patients on hemodialysis, and in a patient population with much higher baseline PTH levels.     

Cultural comparison of symptoms in patients on maintenance hemodialysis

Although symptoms are common and frequently severe in patients on maintenance hemodialysis, little is known about the relationship between cultural background and symptom burden. The aim of this study was to explore differences in the prevalence and severity of symptoms between American and Italian hemodialysis patients. We administered the 30‐item Dialysis Symptom Index to American and Italian patients receiving maintenance hemodialysis during routine dialysis sessions. The prevalence and severity of individual symptoms were compared between patient populations, adjusting for multiple comparisons. Multivariable logistic regression and ordinal logistic regression were used to assess the independent associations of cultural background with the prevalence and severity of symptoms, respectively. We enrolled 75 American and 61 Italian patients. American patients were more likely to be black (36% vs. 0%, P<0.001) and diabetic (53% vs. 13%, P<0.001). Italian patients were more likely to report decreased interest in sex, decreased sexual arousal, feeling nervous, feeling irritable, and worrying (P<0.001, respectively). Adjustment for demographic and clinical variables had no impact on these cultural differences in symptom prevalence. The median severity of 11 symptoms including muscle soreness, muscle cramps, and itching was greater among Americans (P<0.001, respectively), although nearly all of these differences were rendered nonstatistically significant with adjustment for race, diabetes, and/or Kt/V. Italian patients receiving chronic hemodialysis report a greater burden of symptoms than American patients, particularly those related to sexual dysfunction and psychosocial distress. These findings suggest that cultural background may affect adaptation to chronic hemodialysis therapy.     

Longitudinal associations of depressive symptoms and pain with quality of life in patients receiving chronic hemodialysis

Depressive symptoms and pain are common in patients on chronic hemodialysis (HD), yet their associations with quality of life (QOL) are not fully understood. We sought to characterize the longitudinal associations of these symptoms with QOL. As part of a trial comparing two symptom management strategies in patients receiving chronic HD, we assessed depressive symptoms using the Patient Health Questionnaire‐9 (PHQ‐9), and pain using the Short Form McGill Pain Questionnaire (SF‐MPQ) monthly over 24 months. We assessed health‐related QOL (HR‐QOL) quarterly using the Short Form 12 (SF‐12) and global QOL (G‐QOL) using a single‐item survey. We used random effects linear regression to analyze the independent associations of depressive symptoms and pain, scaled based on 5‐point increments in symptom scores, with HR‐QOL and G‐QOL. Overall, 286 patients completed 1417 PHQ‐9 and SF‐MPQ symptom assessments, 1361 SF‐12 assessments, and 1416 G‐QOL assessments. Depressive symptoms were independently and inversely associated with SF‐12 physical HR‐QOL scores (β = ?1.09; 95% confidence interval [CI]: ?1.69, ?0.50, P < 0.001); SF‐12 mental HR‐QOL scores (β = ?4.52; 95% CI: ?5.15, ?3.89, P < 0.001); and G‐QOL scores (β = ?0.64; 95%CI: ?0.79, ?0.49, P < 0.001). Pain was independently and inversely associated with SF‐12 physical HR‐QOL scores (β = ?0.99; 95% CI: ?1.30, ?0.68, P < 0.001) and G‐QOL scores (β = ?0.12; 95%CI: ?0.20, ?0.05, P = 0.002); but not with SF‐12 mental HR‐QOL scores (β = ?0.16; 95%CI: ?0.050, 0.17, P = 0.34). In patients receiving chronic HD, depressive symptoms and to a lesser extent pain, are independently associated with reduced HR‐QOL and G‐QOL. Interventions to alleviate these symptoms could potentially improve patients' HR‐QOL and G‐QOL.     

Use of 3‐hour daily hemodialysis and paricalcitol in patients with severe secondary hyperparathyroidism: A case series

Patients with poor metabolic control receiving conventional hemodialysis are at risk for developing severe secondary hyperparathyroidism. We postulated that daily hemodialysis may be effective at controlling parathyroid hormone (PTH) in the setting of severe secondary hyperparathyroidism by improving the control of hyperphosphatemia and allowing increased use of vitamin D analogs. We present 5 patients with severe secondary hyperparathyroidism (median iPTH=1783 pg/mL) who were treated with 3‐hour daily hemodialysis (3 hours × 6 times a week). Daily hemodialysis, at 1 year, was associated with a 70.4% reduction in median PTH (1783 pg/mL [interquartile range: 1321–1983]–472 pg/mL [334, 704], P<0.001). Additionally, there was an increase in paricalcitol dose from 0 mcg/d to 10.8 (2.00, 11.7) mcg/d, a 39% reduction in calcium × phosphorus product (80.3 ± 26.8–48.9 ± 14.0, P<0.01), a 52% reduction in serum phosphorus (9.90 ± 2.34–4.75 ± 0.79 mg/dL, P<0.0001), and a 17.6% increase in serum calcium (8.18 ± 2.04–9.62 ± 0.93 mg/dL, P<0.01). Three‐hour daily hemodialysis with the use of high‐dose paricalcitol is associated with improved control of severe secondary hyperparathyroidism.     

Symmetrical craniofacial hypertrophy in patients with tertiary hyperparathyroidism and high‐dose cinacalcet exposure

We are reporting on a series of two patients with end‐stage renal disease on hemodialysis, presented for surgical parathyroidectomy secondary refractory hyperparathyroidism. Both patients had failed maximized medical managements, including higher‐than‐usual doses of the calcimimetic cinacalcet (270 and 180 mg/day, respectively). On physical exam, both patients had marked symmetrical craniofacial hypertrophy with coarse distortion of facial features, similar in appearance to past reports of Sagliker syndrome. On X‐ray and computed tomographic exam, they had peculiar areas of bone absorption on the skull, imitating the radiologic appearance of multiple myeloma. Bone biopsy of the maxilla, however, did not show the expected brown tumor, but rather described only fibrosis and reactive bone formations. This phenotype developed while being on cinacalcet, progressed despite escalation of therapy, and improved only after parathyroidectomy. Both patients developed massive “hungry bone syndrome” after parathyroidectomy necessitating prolonged IV calcium infusion. This pattern of severe facial distortion likely represented an adverse consequence of severe tertiary hyperparathyroidism, along with supraphysiologic dose of cinacalcet administration and 25‐hydroxy vitamin D deficiency in sensitive individuals. The genetic base of this observation remained unexplained.     

Prevalence of 25(OH) vitamin D insufficiency and deficiency in chronic kidney disease stage 5 patients on hemodialysis

Little is known about the magnitude of vitamin D deficiency in patients with stage 5 chronic kidney disease (CKD-5) on hemodialysis (HD). In the present study, we examined the prevalence of vitamin D deficiency in patients with CKD-5 undergoing HD, evaluating the relationship between calcidiol levels with other parameters of mineral metabolism, nutrition/inflammation, functional capacity (FC), and sunlight exposure. Serum 25(OH) vitamin D levels were evaluated in 84 stable patients on chronic HD not receiving vitamin D supplements, with a mean age 58.9+/-16.6 years, during the month of September (end of winter in the southern hemisphere). 25(OH) vitamin D serum levels, intact PTH (iPTH), as well as serum albumin, calcium, phosphorus, and alkaline phosphatase were analyzed in fasting samples. Similarly, protein catabolic rate (PCR) and body mass index (BMI) were determined as nutritional parameters. Functional capacity according to the Karnofsky index, and sunlight exposure were also analyzed. In this study, we considered adequate vitamin D levels those above 30 ng/mL (U.S.A. National Kidney Foundation DOQI Guidelines), vitamin D insufficiency when levels were between 15 and 30 ng/mL, and vitamin D deficiency when levels were below 15 ng/mL. The mean 25(OH) D levels were significantly higher in men than in women (28.6 vs. 18.9 ng/mL; p=0.001). Vitamin D insufficiency was found in 53.5% of the patients (n=45) and vitamin D deficiency in 22.6% (n=19). In the univariate analysis, there were no correlations between 25(OH) D levels with age, iPTH, calcium, or phosphorus. There were positive correlations between serum 25(OH) D levels and degrees of sunlight exposure (R=0.55; p<0.0001), serum creatinine (r=0.38; p<0.001), serum albumin (r=0.22; p=0.04), and a negative correlation with BMI (r=-0.26; p=0.01). In the multiple regression analysis, only sunlight exposure (B=0.361), BMI (B=-0.23), and gender (B=-0.27) were significantly associated with 25(OH) D levels. Patients with FC 1 to FC 2 (n: 70%, 83.3%) had significantly higher 25(OH) D serum levels compared with FC 3 to FC 4 patients (n: 14%, 16.6%): 25.9 vs. 17.1 ng/mL (p=0.03). These results indicate that vitamin D insufficiency/deficiency is highly prevalent (76.1%) at the end of winter, in stage 5 CKD patients on HD, and lower values seem to be related to decreased sunlight exposure, female gender, increased BMI, and worse functional class.     

Weekly high‐dose ergocalciferol to correct vitamin D deficiency/insufficiency in hemodialysis patients: A pilot trial

Controversy exists on which vitamin D (D2 or D3) and which dosage scheme is the best to obtain and maintain adequate 25 OH D levels in dialysis patients safely. We tried to determine whether high‐dose vitamin D2 supplementation could obtain optimal vitamin D status without inducing hypercalcemia. We studied 82 patients on dialysis not taking active vitamin D therapy and supplemented them with oral vitamin D2 72,000 IU/week for 12 weeks followed by 24,000 IU/week as maintenance therapy during 36 weeks. By week 12, serum 25(OH)D increased from 15.2 ± 5.4 to 42.5 ± 13.2 ng/mL (P < 0.01) at week 12 and remained optimal (34.7 ± 12.0); 84.8% of the patients reached values ≥30 ng/mL. iPTH and alkaline phosphatase did not change at 48 weeks compared with baseline, but bone alkaline phosphatase decreased significantly (54.3 ± 46.0 to 44.3 ± 25.0; P = 0.02). Uncorrected serum Ca increased significantly at the end of follow‐up (9.03 ± 0.42 to 9.14 ± 0.62; P = 0.04); hypercalcemia was presented in two patients in the first control visit (week 12), in one patient in the second control (week 30), and in one patient in the third control (week 48). In 222 serum calcium determinations during follow‐up, hypercalcemia was observed in only 1.8% of cases. This vitamin D2 oral regimen with initial high doses was safe and sufficient to obtain and maintain optimal serum 25(OH)D concentrations and prevent vitamin D insufficiency in chronic kidney disease patients on dialysis.     

Facial disfigurement due to osteitis fibrosa cystica or brown tumor from secondary hyperparathyroidism in patients on dialysis: A systematic review and an illustrative case report

Osteitis fibrosa cystica (OFC) is the most frequent type of osseous change in renal osteodystrophy affecting the majority of dialysis patients. Brown tumors are a severe form of OFC. The involvement of the craniofacial skeleton causing facial disfigurement in patients on dialysis appears to be limited to case reports. After searching PubMed, we performed a systematic review of 127 cases with a severe form of OFC resulting in a facial disfigurement to understand possible determinants for this condition. We found that since the first published case in 1974, and after a peak in 1996, there appears to be an increase in published reported cases. Only 27.6% of these cases were published in nephrology journals. The most common region for reported cases was North America. Mean age of these patients was 31.2 years with a mean dialysis duration of 7 years. Almost 67% were women, and almost all were on hemodialysis. The disease tended to most commonly localize to the maxilla (73.2%) and mandible (57.5%). As part of the treatment, 59% of patients had a parathyroidectomy. More than one‐third (35.4%) had symptomatic improvement at follow‐up. Mean follow‐up was 1.6 years. Clinicians should be aware of this clinical presentation of a severe form of OFC and/or brown tumors. Timely diagnosis and intervention may help to prevent or decrease destructive bone changes and reduce negative psychological consequences of facial disfigurement.     

Pulmonary hypertension in patients on chronic hemodialysis and with heart failure

Pulmonary hypertension (PH) is linked to chronic kidney disease. However, few studies have examined the prevalence, risk factors, or outcomes of PH in patients with chronic hemodialysis and concomitant heart failure. This retrospective cohort study enrolled 160 patients with a history of acute decompensated heart failure after maintenance hemodialysis therapy. All patients were prospectively observed until December 2013 or death. PH was defined as pulmonary artery systolic pressure >35 mmHg, as determined through echocardiography. Fifty‐one (32%) patients had PH, more of whom were female (70% vs. 52%, P = 0.04). The patients with PH had a lower body mass index (21.8 vs. 23.0, P = 0.03), higher cardiothoracic ratio (55% vs. 52%, P = 0.006), larger left atrium (38.5 vs. 35.7 mm, P = 0.01), and an increased proportion of mitral regurgitation (MR) (73% vs. 38%, P < 0.001) compared with the patients who did not have PH. In the multivariate regression analysis, MR was associated most strongly with PH (odds ratio 3.75, 95% confidence interval [CI]: 1.67–8.43, P = 0.001). In the multivariate Cox proportional hazard models, PH was related independently to all‐cause mortality (hazard ratio [HR], 3.11; 95% CI, 1.53–6.31; P = 0.002) and combined cardiovascular events (HR, 2.71; 95% CI, 1.66–4.44; P < 0.001) after the model was adjusted for conventional cardiovascular risk factors. PH is related to MR and independently associated with increased all‐cause mortality and cardiovascular events in patients with chronic hemodialysis and heart failure.     

Cephalic arch stenosis in patients with fistula access for hemodialysis: relationship to diabetes and thrombosis

Numerous studies have identified the fistula as the best access for hemodialysis with fewest complications. The radiocephalic fistula (RCF) is the first access of choice, but often results in poor maturation. Therefore, an increased number of brachiocephalic fistulas (BCF) have been placed. Cephalic arch stenosis (CAS) can occur in patients with fistula access. The current study was done to determine the incidence and associated comorbidities in patients with BCF or RCF who have CAS. A retrospective review of 450 hemodialysis patients in 3 outpatient hemodialysis units between July 1, 2000 and July 1, 2005 (60 months) was preformed. We reviewed demographics, medications, and indications for venograms. Interventional Radiologists reviewed the venograms for evidence of CAS. Radiology reports were screened to determine incidence of thrombosis, treatment with either angioplasty or stent placement and if a complication such as venous rupture occurred. One hundred and twenty-seven patients had fistula access with at least 1 venogram. Of these, 30 were RCF and 97 were BCF. Cephalic arch stenosis occurred in 77% of patients with BCF and in 20% of patients with RCF. Those with diabetes had a lower rate of occurrence than those without (p<0.01). Cephalic arch stenosis led to a high rate of thrombosis (p<0.01). The probability of having multiple radiology procedures was higher with CAS than without (p<0.01). Cephalic arch stenosis is an important problem in hemodialysis patients who have fistula access, and contributes to thrombosis. Diabetes was found to have a negative association with CAS for undefined reasons. Attempts to understand this relationship are important.     

Effects of flaxseed consumption on systemic inflammation and serum lipid profile in hemodialysis patients with lipid abnormalities

Inflammation and lipid abnormalities are two important risk factors for cardiovascular disease in hemodialysis (HD) patients. The present study was designed to investigate the effects of flaxseed consumption on systemic inflammation and serum lipid profile in HD patients with lipid abnormalities. This was an unblinded, randomized clinical trial. Thirty HD patients with dyslipidemia (triglyceride >200 mg/dL and/or high‐density lipoprotein‐cholesterol (HDL‐C) <40 mg/dL) were randomly assigned to either a flaxseed or control group. Patients in the flaxseed group received 40 g/day ground flaxseed for 8 weeks, whereas patients in the control group received their usual diet, without any flaxseed. At baseline and at the end of week 8, 7 mL of blood was collected after a 12‐ to 14‐hour fast and serum concentrations of triglyceride, total cholesterol, low‐density lipoprotein‐cholesterol (LDL‐C), HDL‐C, and C‐reactive protein (CRP) were measured. Serum concentrations of triglyceride (P < 0.01), total cholesterol (P < 0.01), LDL‐C (P < 0.01), and CRP (P < 0.05) decreased significantly in the flaxseed group at the end of week 8 compared with baseline, whereas serum HDL‐C showed a significant increase (P < 0.01). These changes in the flaxseed group were significant in comparison with the control group. The study indicates that flaxseed consumption improves lipid abnormalities and reduces systemic inflammation in HD patients with lipid abnormalities.     

Clinical correlates and treatment of bone/joint pain and difficulty with sexual arousal in patients on maintenance hemodialysis

Bone/joint pain and difficulty with sexual arousal are prevalent, frequently severe, and potentially treatable in patients on maintenance hemodialysis. However, the mediators and adequacy of treatment for these symptoms have been less well studied. We sought to assess the clinical correlates and treatment of these symptoms in patients receiving chronic hemodialysis. Using the Dialysis Symptom Index, we assessed the presence and severity of bone/joint pain and difficulty with sexual arousal in 75 patients on chronic hemodialysis. Associations of demographic and clinical variables with these 2 symptoms were assessed. We also recorded the use of analgesics for bone/joint pain and, among men, phosphodiesterase-5 inhibitors for difficulty with sexual arousal. Twenty-eight patients (37%) reported bone/joint pain, of whom 20 (71%) described it as moderate to severe. Nineteen of 50 male patients (38%) reported difficulty with sexual arousal, which was described as moderate to severe by 15 (79%). Patients' demographic and clinical characteristics were not correlated with bone/joint pain. Among men, there were no correlations between patients' demographic and clinical characteristics and difficulty with sexual arousal. Only 48% of patients with bone/joint pain were receiving analgesics, while 21% of men who described difficulty with sexual arousal were receiving phosphodiesterase-5 inhibitors. Demographic, clinical, and dialysis-related variables are poorly correlated with bone/joint pain and difficulty with sexual arousal. However, these symptoms are prevalent and under-treated, which should spur efforts to assess the impact of improving provider assessment and treatment of these symptoms on patient outcomes, including health-related quality of life.     

Intradialytic changes of serum magnesium and their relation to hypotensive episodes in hemodialysis patients on different dialysates

Magnesium is a crucial mineral, involved in many important physiological processes. Magnesium plays a role of maintaining myocardial electrical stability in hemodialysis patients. Intradialytic hypotension is a common complication of dialysis and it is more common with acetate dialysate. The significance of the intradialytic changes of magnesium and their relation to parathyroid hormone (PTH) level and calcium changes during dialysis, and their relation to hypotensive episodes during dialysis are interesting. The aim of this work is to investigate the intradialytic changes of serum magnesium in chronic hemodialysis patients with different hemodialysis modalities and the relation to other electrolytes and to PTH, and also the relation to intradialytic hypotension. The present study was conducted on 20 chronic renal failure patients. All patients were on regular hemodialysis thrice weekly 4 hr each using acetate dialysate (group I). To study the effect of an acetate-based dialysate vs. a bicarbonate-based dialysate on acute changes of magnesium, calcium, phosphorus, and PTH during a hemodialysis session, the same patients were shifted to bicarbonate dialysis (group II). All patients were subjected to full history and clinical examination, predialysis laboratory assessment of blood urea nitrogen (BUN), serum creatinine, albumin, and hemoglobin, serial assessment of magnesium, calcium, phosphorus, and parathyroid hormone at the start of the hemodialysis session, 2 hr later, and at the end of the session, blood pH, and electrocardiogram (ECG) presession and postsession. All patients were urged to fix their dry weight, diet, and current medications. None of the patients had diabetes, neoplasia, liver disease, or cachexia, nor had they been recently on magnesium-containing drugs or previously parathyroidectomized. Hemodialysis sessions were performed by volumetric dialysis machines using the same electrolyte composition. Magnesium level significantly increased in the bicarbonate group at the end of dialysis (0 hr: 2.73+/-0.87, 2 hr: 3.21+/-1.1, and at 4 hr: 5.73+/-1.45 mg/dL, p value <0.01), while it significantly decreased in the acetate group (0 hr: 3.00+/-0.58, 2 hr: 2.26+/-0.39, 4 hr: 1.97+/-0.33 mg/dL, p value <0.01). Calcium level significantly increased in the bicarbonate group (p=0.024) but not in the acetate group. Phosphorus level significantly decreased in both acetate and bicarbonate groups. PTH level did not significantly change in either group, p value > or =0.05. Blood pH significantly increased, changing from acidic to alkaline pH, with both modalities of hemodialysis. ECG showed no significant changes during sessions with either type of dialysate. Hypotension was significantly higher in group I compared with group II (p=0.01), and this hypotension was positively correlated with a decrease in serum magnesium level in group I. Intradialytic changes in serum magnesium have no correlation with intradialytic changes in serum calcium or with PTH level. However, it was significantly correlated with hypotension during the dialysis session, especially with acetate dialysate. Further investigations are needed to determine whether or not this is true in patients using bicarbonate dialysis.