Phosphorus control in peritoneal dialysis patients.

Hyperphosphatemia is independently associated with an increased risk of death among dialysis patients. In this study, we have assessed the status of phosphate control and its clinical and laboratory associations in a large international group of patients on chronic peritoneal dialysis (PD) treatment. This cross-sectional multicenter study was carried out in 24 centers in three different countries (Canada, Greece, and Turkey) among 530 PD patients (235 women, 295 men) with a mean+/-s.d. age of 55+/-16 years and mean duration of PD of 33+/-25 months. Serum calcium (Ca(2+)), ionized Ca(2+), phosphate, intact parathyroid hormone (iPTH), 25-hydroxy vitamin D(3), 1,25-dihydroxy vitamin D(3), total alkaline phosphatase, and bone alkaline phosphatase concentrations were investigated, along with adequacy parameters such as Kt/V, weekly creatinine clearance, and daily urine output. Mean Kt/V was 2.3+/-0.65, weekly creatinine clearance 78.5+/-76.6 l, and daily urine output 550+/-603 ml day(-1). Fifty-five percent of patients had a urine volume of <400 ml day(-1). Mean serum phosphorus level was 4.9+/-1.3 mg per 100 ml, serum Ca(2+) 9.4+/-1.07 mg per 100 ml, iPTH 267+/-356 pg ml(-1), ionized Ca(2+) 1.08+/-0.32 mg per 100 ml, calcium phosphorus (Ca x P) product 39+/-19 mg(2)dl(-2), 25(OH)D(3) 8.3+/-9.3 ng ml(-1), 1,25(OH)(2)D(3) 9.7+/-6.7 pg ml(-1), total alkaline phosphatase 170+/-178 U l(-1), and bone alkaline phosphatase 71+/-108 U l(-1). While 14% of patients were hypophosphatemic, with a serum phosphorus level lower than 3.5 mg per 100 ml, most patients (307 patients, 58%) had a serum phosphate level between 3.5 and 5.5 mg per 100 ml. Serum phosphorus level was 5.5 mg per 100 ml or greater in 28% (149) of patients. Serum Ca(2+) level was > or =9.5 mg per 100 ml in 250 patients (49%), between 8.5 and 9.5 mg per 100 ml in 214 patients (40%), and lower than 8.5 mg per 100 ml in 66 patients (12%). Ca x P product was >55 mg(2)dl(-2) in 136 patients (26%) and lower than 55 mg(2)dl(-2) in 394 patients (74%). Serum phosphorus levels were positively correlated with serum albumin (P<0.027) and iPTH (P=0.001), and negatively correlated with age (P<0.033). Serum phosphorus was also statistically different (P = 0.013) in the older age group (>65 years) compared to younger patients; mean levels were 5.1+/-1.4 and 4.5+/-1.1 mg per 100 ml, respectively, in the two groups. In our study, among 530 PD patients, accepted uremic-normal limits of serum phosphorus control was achieved in 58%, Ca x P in 73%, serum Ca(2+) in 53%, and iPTH levels in 24% of subjects. Our results show that chronic PD, when combined with dietary measures and use of phosphate binders, is associated with satisfactory serum phosphorus control in the majority of patients.

Severe vitamin D deficiency in chronic renal failure patients on peritoneal dialysis.

UNLABELLED: The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.

MR peritoneography in complications of continuous ambulatory peritoneal dialysis.

BACKGROUND: We evaluated the usefulness of magnetic resonance (MR) peritoneography for the examination of complications from continuous ambulatory peritoneal dialysis (CAPD). METHODS: MR peritoneography was performed in 20 patients who had suspected CAPD-related complications. Patients who had active peritonitis were not included in the study. Before MR imaging, a mixture of 2000 mL of peritoneal dialysis solution and 20 mL of gadopentetate dimeglumine was instilled into the peritoneal cavity. MR imaging was performed on a 1.0-Tesla system using a body coil. Axial, coronal, and sagittal fat-saturated fast spoiled gradient echo (repetition/echo times, 100/6.3 ms; flip angle, 90 degrees), axial fat-saturated T2-weighted fast spin echo (repetition/echo times, 6000/107 ms), and coronal fat-saturated T2-weighted fast spin echo (repetition/echo times, 3000/96.2 ms) images of the abdomen and the pelvis were obtained. After drain-age, triplanar fat-saturated fast spoiled gradient echo images were repeated with the same parameters. RESULTS: Homogeneous distribution of the dialysate in the peritoneal cavity was detected in 18 patients (90%). In 12 patients (60%), fluid leaks were discovered peripheral to the exit site, tunnel, and site of peritoneal entrance of the catheter. Fluid leaks through the abdominal wall in five patients (25%), retroperitoneum in one patient (5%), and a previous operation site in one patient (5%) were demonstrated. No abnormal finding was detected in three patients (15%) who had clinically suspected complications, whereas a dialysate leak was found in two patients (10%) who had no significant finding at physical examination. CONCLUSIONS: MR peritoneography provides detailed information about the anatomic distribution of dialysate leaks in patients treated with CAPD and poses no risks associated with ionizing radiation and nephrotoxic contrast medium.

Long-term outcome of renal transplantation in patients with familial Mediterranean fever amyloidosis: a single-center experience.

Although recurrence of amyloid A deposition in the allograft can be seen in patients with secondary amyloidosis due to familial Mediterranean fever (FMF), renal transplantation remains to be a choice of treatment for end-stage renal disease. The aim of this study was to determine short- and long-term results of renal transplantation in patients with FMF amyloidosis. We compared the outcomes of 17 patients with FMF amyloidosis among 431 (3.9%) transplants with 209 control patients. We observed 93% and 94% graft and patient survivals at 1 year, and 89% and 90% at 5 years. Also, the mean serum creatinine levels at 1 and 5 years posttransplant were similar. Recurrence of amyloidosis was documented in two allograft recipients presenting with nephrotic range proteinuria (12%), one of whom lost the allograft due to recurrence. Eleven patients had FMF gene analysis. The results of MEFV mutation analyses were: M694V/M694V homozygote in six patients, M694V/EQ148 in one patient, M694V/V726A in one patient, 680M-I/E148Q in one patient. FMF gene analysis was negative in two patients. Recurrence was noticed in one patient with M694V/M694V, while the other did not have an FMF gene analysis. Colchicine was reduced in nine patients due to side effects. In conclusion, the long-term outcomes of transplantation in patients with amyloidosis secondary to FMF is similar to that in the general transplant population and maintenance colchicine, even at low dose, appears to effectively prevent recurrence of amyloidosis in the allograft.

Effect of fluid and sodium removal on mortality in peritoneal dialysis patients.

UNLABELLED: Effect of fluid and sodium removal on mortality in peritoneal dialysis patients. BACKGROUND: Adequacy of peritoneal dialysis (PD) traditionally is assessed using Kt/V(urea) and total creatinine clearance (TCC). However, this approach underestimates the importance of fluid and sodium removal. The aim of this study was to determine the effect of fluid and sodium removal on morbidity and mortality in PD patients. METHODS: One hundred twenty-five PD patients were monitored for three years from the beginning of the treatment. The effects of demographic features, comorbidity, peritonitis rate, blood pressure, medications, blood biochemistry, peritoneal membrane transport characteristics, residual renal function (RRF), Kt/V(urea), TCC, normalized protein nitrogen appearance (nPNA), and removal of sodium and fluid on mortality were evaluated. Total and cardiovascular hospitalization rates were also recorded. A Cox proportional hazards model was used to determine factors predicting mortality. RESULTS: In the Cox model, comorbidity, total sodium and fluid removals, hypertensive status, serum creatinine, and RRF were independent factors affecting survival. In contrast, Kt/V(urea) or TCC did not affect the adjusted survivals. Total sodium and fluid removal and hypertensive status also significantly influenced the hospitalization rate. Systolic and diastolic blood pressures were negatively correlated with total fluid (P < 0.001) and sodium removal (P < 0.001). CONCLUSIONS: Together, these findings suggest that removal of sodium and fluid is a predictor of mortality in PD patients, whereas Kt/V(urea) and TCC are not factors. Adequate fluid and sodium balance is crucial for the management of patients on PD.

Renal Doppler ultrasonographic findings in earthquake victims with crush injury.

OBJECTIVE: In the Marmara earthquake, which occurred on August 17, 1999, 639 people had renal complications, and 477 needed hemodialysis treatment because of acute renal failure due to crush injury. Our objective was to use Doppler ultrasonography as a noninvasive procedure to provide renal hemodynamic information. METHODS: We evaluated 9 patients with severe crush injury by using Doppler ultrasonography to measure renal resistive indexes within 16 to 32 hours after the earthquake and 6 weeks later. All patients had acute renal failure and underwent hemodialysis. RESULTS: All measured initial resistive indexes were high (mean +/- SD, 0.83 +/- 0.08), and they were correlated with the number of hemodialysis sessions (r = 0.703; P = .034), the duration of hemodialysis treatment (r = 0.819; P = .007), and oligoanuria (r = 0.937; P < .0001). All patients recovered from the acute renal failure, and repeated Doppler ultrasonography showed significant decreases in resistive indexes (0.59 +/- 0.07; P < .01) and renal lengths (P < .05). CONCLUSIONS: In crush injury, measurement of renal resistive indexes can be useful for the prognosis of recovery from acute renal failure.

Recognition of neurocognitive dysfunction in chronic hemodialysis patients.

We sought to determine the prevalence, recognition, and consequences of mental impairment among chronic hemodialysis patients. We administered the Mini Mental Status Exam (MMSE), a brief validated method for assessing cognitive mental status that is commonly used by clinicians, to 84 patients from our dialysis units. To determine the clinical implications of mental impairment, we obtained Kt/V, albumin, protein catabolic rate, blood pressure, and hematocrit values. We found that 21% of subjects had mild mental impairment (MMSE 18 to 23) and that 11% had moderate-severe mental impairment (MMSE 0 to 17). We found no relationship between MMSE score and years on dialysis, Kt/V value, hematocrit value, or erythropoietin use. On univariate analysis, MMSE score was associated with albumin, protein catabolic rate, inter-dialytic weight gain, number of co-morbid conditions, number of hospitalizations. Outcomes on univariate analysis were further analyzed by multivariate analysis. There was an independent relationship between decrement in MMSE score and lower protein catabolic rate and increased hospitalization number and number of co-morbid conditions. Based on our findings, we recommend that clinicians routinely screen hemodialysis patients for mental impairment and target impaired patients for interventions to improve mental status and associated adverse outcomes.

Comparison of the effects of hospitalization and antibiotic usage on the aerobic intestinal flora.

Antimicrobial resistance among bacteria has arisen ever since antimicrobial agents were introduced in the clinic. Unfortunately, it seems that resistance is now emerging at a more rapid rate than ever before, as a consequence of the widespread use of antimicrobial agents. The spread of these multiresistant microorganisms is an increasing threat in many countries. The human intestinal flora is a huge potential reservoir of resistant microorganisms. Antimicrobial resistance in clinical isolates may cause serious infections and treatment failure, and lead to the use of higher doses or more toxic alternative drugs. This study was planned so as to compare the effects of hospitalization and antibiotic usage on the aerobic intestinal flora and included 43 hospitalized adult patients without any previous history of hospitalization and antibiotic usage during the last 30 d. Patients were divided according to their antimicrobial therapy, into treated and untreated groups. The individual use of antimicrobials was recorded. Antibiotic usage was found to be more effective on the aerobic intestinal flora compared with hospitalization without such medication.

Remission of nephrotic syndrome after removal of localized Castleman's disease.

Renal complications of Castleman's disease are uncommon. Among the various renal disorders, including mesangial proliferative glomerulonephritis, membranous glomerulonephritis, and minimal change disease, nephrotic syndrome attributable to renal amyloidosis is very rarely reported. We report a case of mixed type of localized Castleman's disease complicated with nephrotic syndrome. Renal biopsy was performed. The deposition of AA amyloidosis was shown. After the removal of two mesenteric lymphoid masses, the proteinuria was gradually decreased and disappeared. Renal biopsy was repeated after 14 months, and, despite complete remission of nephrotic syndrome, no regression in amyloid deposition was found.

The longitudinal effect of a single peritonitis episode on peritoneal membrane transport in CAPD patients.

OBJECTIVE: To evaluate the longitudinal effect of a single peritonitis episode on peritoneal membrane transport. DESIGN: A prospective longitudinal study. SETTING: Department of nephrology in a university hospital. PATIENTS: Eighteen continuous ambulatory peritoneal dialysis patients with peritonitis. METHODS: Peritoneal transport for low, middle, and high molecular weight (MW) solutes was evaluated by peritoneal equilibration test (PET). The first PET was performed on the day following the diagnosis of peritonitis. The test was repeated at weeks 1, 2, 4, 12, and 24 and the results were compared to baseline PET data obtained before peritonitis. In addition, dialysate CA125 concentration and leukocyte count were measured. RESULTS: During peritonitis there were significant increases in dialysate-to-plasma (D/P) ratios for all low, middle, and high MW solutes except potassium, and decreases in D4/D0 glucose ratio and ultrafiltration (UF) volume. Over the subsequent 2 weeks, solute transport gradually decreased to the baseline values then remained unchanged during follow-up. Although net UF volume demonstrated a similar course during the study, it did not completely return to the baseline value. No decrease in D/P sodium ratio was found at 60 minutes during the PET performed 24 weeks after peritonitis. The percent change in solute transport during peritonitis compared to baseline value was significantly correlated with a solute's MW (r = 0.776, p = 0.014). The slope of the regression line for D/P ratios versus MW, in double logarithmic scale, before peritonitis (-0.73 +/- 0.09) was steeper than the slope during peritonitis (-0.59 +/- 0.08). CONCLUSIONS: These findings indicate that a single peritonitis episode does not permanently affect peritoneal solute transport. However, the loss of net UF that accompanies peritonitis is not completely recovered, probably due to impairment of transcellular water transport. The transport changes associated with peritonitis may be due to the combined effect of increased effective peritoneal surface area and intrinsic permeability. Our findings suggest that the latter mechanism seems to be more important.

Delivery of healthy infant during hemodialysis session.

Acute renal failure secondary to bilateral ureteral obstruction in pregnancy is rare. We describe a case of acute renal failure secondary to bilateral ureteral obstruction. A 27 year-old woman at 35 weeks' gestation was referred to our hospital with a diagnosis of acute renal failure. The patient had been well until four days earlier, when she developed an abrupt anuria. She had been administrated excessive amounts of fluids, and unresponsive to parenteral furosemide. She had mild pitting oedema and an S3 gallop with crackles in the lungs. The uterus was enlarged to the expected size with a cervical dilatation of 2 cm in diameter. Her serum creatinine level was 7.0 mg/dl. Renal ultrasound showed bilateral hydronephrosis of severe degree. The patient was immediately hemodialyzed for advanced renal failure with hypervolemia, and a healthy infant was born at the third hour of the HD session without any complication. On the next day, her urine volume was 200 ml/day and serum creatinine level was 6.8 mg/dl. For this reason, the patient underwent cystoscopy and ureteral stents were inserted bilaterally. There was no evidence of ureteral stones or obstructive lesions. After the stenting, the urine volume increased and serum creatinine was decreased gradually to normal level at the seventh day of postpartum. Two weeks later ureteral stents were removed and both infant and patient were completely healthy. To the best of our knowledge, this is the first case of delivery of an infant during a haemodialysis session.

Carotid intima-media thickness and ACE-gene polymorphism in hemodialysis patients.

BACKGROUND: Carotid artery intima-media thickness (CIMT) has been used as a marker of atherosclerosis. An insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is associated with various cardiovascular diseases. This study is aimed at evaluating early atherosclerotic involvement of carotid vessels and the relation to known risk factors and ACE gene I/D in hemodialysis (HD) patients. METHODS: We measured CIMT using high-resolution B-mode ultrasonography in 51 non-diabetic HD patients and in 70 age- and sex-matched healthy controls, and evaluated the factors influencing CIMT. An I/D polymorphism in intron 16 of the gene coding for ACE was analysed by polymerase chain reaction. RESULTS: The mean CIMT was significantly higher in HD patients than in healthy subjects (p<0.0001). In multiple regression analysis, independent risk factors for increased CIMT in HD patients were predialysis systolic blood pressure (p<0.001) and ACE D allele (p<0.01). CONCLUSIONS: The present data suggest that CIMT is enlarged in HD patients. The ACE gene seems to be a candidate for influencing the CIMT and might therefore be involved in an HD patient's predisposition to the development of atherosclerosis.

The impact of withdrawing ACE inhibitors on erythropoietin responsiveness and left ventricular hypertrophy in haemodialysis patients.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors have the capability of decreasing left ventricular mass index (LVMI) in chronic haemodialysis (HD) patients. On the other hand, recent reports provide conflicting information regarding the impact of ACE inhibitors on responsiveness to recombinant human erythropoietin (rHuEpo), and there are no data about the effect of withdrawing ACE inhibitors both on rHuEpo response and LVMI in HD patients. METHODS: ACE inhibitors were switched to another antihypertensive medication in 23 out of 68 patients in our HD unit who were receiving both rHuEpo and an ACE inhibitor for more than 1 year. Blood pressure at the pre- and post-dialysis phases, haematocrit levels and rHuEpo doses were determined at the end of the first and of the third years, and the LVMI was determined at the end of the third year. Statistical analyses were done in 15 patients in whom the study could be completed. RESULTS: The mean (+/-SD) haematocrit level was increased from 26.3+6.4% to 29.8+/-6.3% at the first year (P<0.05), and to 29.4+/-6.5% at the third year (P<0.05 vs before), while the mean dose of rHuEpo was decreased from 208.3+/-99.0 UI/kg/week to 141.0+/-91.8 at the first year (P=0.01), and to 141.4+/-81.0 at the third year (P=0.01 vs before). Administration of rHuEpo had been stopped in two patients at the end of the first year. The mean blood pressure level and the mean LVMI were not changed (P>0.05 vs before). There were no significant changes in dialysis parameters, iron status, plasma renin activities, and levels of aldosterone, intact parathyroid hormone, aluminum and erythropoietin. CONCLUSION: The findings of this small uncontrolled study indicate that withdrawal of ACE inhibitors in hypertensive chronic HD patients receiving rHuEpo may result in an increase in haematocrit level, and a decrease in dose of rHuEpo without any significant changes in the blood pressure level and LVMI. Controlled prospective studies are needed to clarify this issue.