Stanley Fan

Fluid status in peritoneal dialysis patients: the European Body Composition Monitoring (EuroBCM) study cohort

Background Euvolemia is an important adequacy parameter in peritoneal dialysis (PD) patients. However, accurate tools to evaluate volume status in clinical practice and data on volume status in PD patients as compared to healthy population, and the associated factors, have not been available so far. Methods We used a bio-impedance spectroscopy device, the Body Composition Monitor (BCM) to assess volume status in a cross-sectional cohort of prevalent PD patients in different European countries. The results were compared to an age and gender matched healthy population. Results Only 40% out of 639 patients from 28 centres in 6 countries were normovolemic. Severe fluid overload was present in 25.2%. There was a wide scatter in the relation between blood pressure and volume status. In a multivariate analysis in the subgroup of patients from countries with unrestricted availability of all PD modalities and fluid types, older age, male gender, lower serum albumin, lower BMI, diabetes, higher systolic blood pressure, and use of at least one exchange per day with the highest hypertonic glucose were associated with higher relative tissue hydration. Neither urinary output nor ultrafiltration, PD fluid type or PD modality were retained in the model (total R2 of the modelu200a=u200a0.57). Conclusions The EuroBCM study demonstrates some interesting issues regarding volume status in PD. As in HD patients, hypervolemia is a frequent condition in PD patients and blood pressure can be a misleading clinical tool to evaluate volume status. To monitor fluid balance, not only fluid output but also dietary input should be considered. Close monitoring of volume status, a correct dialysis prescription adapted to the needs of the patient and dietary measures seem to be warranted to avoid hypervolemia.

The Pan-Thames EPS study: treatment and outcomes of encapsulating peritoneal sclerosis

BACKGROUNDnEncapsulating peritoneal sclerosis (EPS) is a disease process that can occur as a complication of peritoneal dialysis (PD). The aim of this study was to make a general assessment of the clinical features, diagnosis, management and outcome of PD-related EPS cases from London and South-East England.nnnMETHODSnQuestionnaires were sent to 11 PD units in March 2007; cases were identified retrospectively. Outcome data on surviving patients were collected in March 2008.nnnRESULTSnA total of 111 patients were identified; the mean time on PD was 82 months (range 8-247). Mortality increased with length of time on PD, being 42% at <3 years (n = 12), 32% at 3-4 years (n = 19), 61% at 5-6 years (n = 31), 54% at 7-8 years (n = 24), 75% at 9-10 years (n = 8) and 59% at >10 years (n = 17). Twelve patients had no previous peritonitis episodes, 28 had one previous episode, 30 had two previous episodes and 33 had three or more previous episodes. Of the patients with PD details available, 41/63 were high (>0.81) transporters and 44/71 had ultrafiltration <1 l/24 h, but 7/63 were low average transporters (0.5-<0.65) and 27/71 had ultrafiltration >1 l/24 h and a few had significant residual renal function. Sixty-five (59%) patients had their PD discontinued prior to diagnosis (51 HD; 14 transplanted). CT scans were performed on 91 patients and laparotomy on 47 patients. Drug treatment consisted of tamoxifen, immunosuppression or both. The median survival was 15 months in patients treated with tamoxifen (n = 17), 12 months in patients treated with immunosuppression (n = 24) and 21 months in patients who received both (n = 13), against 13 months (n = 46) in patients who received no specific treatment. Adhesionolysis was performed in 5 patients, and 39 patients were given parenteral nutrition. The overall mortality was 53% with a median survival of 14 months and a median time to death of 7 months. Conclusion. This is one of the largest cohorts of patients with EPS in the literature. Long-term survival occurred in over 50%, regardless of the various treatments strategies undertaken by the centres.

Efficacy and safety of sevelamer hydrochloride and calcium acetate in patients on peritoneal dialysis

BACKGROUNDnInadequate phosphorus control is associated with increased morbidity and mortality in patients with CKD stage 5. Although phosphate binders are often used in patients on peritoneal dialysis (PD), no large randomized controlled studies evaluating their use solely in this population have previously been reported.nnnMETHODSnIn this multicentre, open-label study, adult patients on PD with serum phosphorus >5.5 mg/dl were randomized (2:1) to 12 weeks of treatment with sevelamer hydrochloride or calcium acetate. Doses were titrated to achieve serum phosphorus of 3.0-5.5 mg/dl. Changes in serum phosphorus, calcium, intact parathyroid hormone (iPTH), lipids and plasma biomarkers were assessed.nnnRESULTSnA total of 253 patients were screened, 143 of whom were randomized (sevelamer hydrochloride, n = 97; calcium acetate, n = 46). Treatment groups were well balanced with regard to baseline demographics. Serum phosphorus levels were significantly reduced after 12 weeks with both sevelamer hydrochloride and calcium acetate (P < 0.001). Serum PTH was also reduced in both groups while serum calcium increased in the calcium acetate group (P = 0.001) but not in the sevelamer hydrochloride group. Sevelamer hydrochloride was also associated with decreases in total cholesterol, low-density lipoprotein cholesterol and uric acid and an increase in bone-specific alkaline phosphatase (all P < 0.001 versus baseline). Both treatments were well tolerated and safety profiles were consistent with previous reports in haemodialysis patients. Hypercalcaemia was experienced by more calcium acetate-treated patients (18 versus 2%; P = 0.001).nnnCONCLUSIONSnIn summary, sevelamer hydrochloride provides a reduction in serum phosphorus compared to that obtained with calcium-based binders in PD patients. The effects of sevelamer hydrochloride appear similar in both PD and haemodialysis populations.

Quality of life of caregivers and patients on peritoneal dialysis

Peritoneal dialysis is the archetypal home-based therapy and is often favoured by patients. However, as patients with end-stage renal failure become more elderly, with more co-morbidity, their dependence on carers to provide physical, emotional and logistical support increases. The effect of this chronic burden has not been systematically studied. We have prospectively studied patients with end-stage renal failure starting peritoneal dialysis and their carers over a 1-year period. We selected a cohort of caregivers that are actively involved with the care of their partners dialysis. Quality of Life (QoL) assessed by SF-36 questionnaires showed the patients and carers had impairment of QoL at the start of dialysis. As expected, the baseline QoL Physical Component Scores highly correlated with co-morbidity and assessment of functional capacity. Scores of all QoL domains improved after 1 year and this reached statistical significance for social functioning for both patients and carers. When we compared carers of highly dependent patients (required to perform daily dialysis) with carers of less dependent patients, we noted that the former had a statistically significant worsening of their mental health but other parameters were not different. We have shown that despite increasing the burden for caregivers, with careful selection, education and support, we did not adversely impact on the QoL of carers whilst there was some evidence of improvement, especially in social functioning. This gives reassurance that establishing dependent patients on PD is compatible with a holistic approach to the patients and their families.

A randomized, crossover design study of sevelamer carbonate powder and sevelamer hydrochloride tablets in chronic kidney disease patients on haemodialysis

Background. Sevelamer carbonate is an improved, buffered form of sevelamer hydrochloride developed for the treatment of hyperphosphataemia in CKD patients. Sevelamer carbonate formulated as a powder for oral suspension presents a novel, patient-friendly alternative to tablet phosphate binders. This study compared the safety and efficacy of sevelamer carbonate powder with sevelamer hydrochloride tablets in CKD patients on haemodialysis. Methods. This was a multi-centre, open-label, randomized, crossover design study. Thirty-one haemodialysis patients were randomly assigned to either sevelamer carbonate powder or sevelamer hydrochloride tablets for 4 weeks followed by a crossover to the other regimen for an additional 4 weeks. Results. The mean serum phosphorus was 1.6 ± 0.5 mmol/L (5.0 ± 1.5 mg/dL) during sevelamer carbonate powder treatment and 1.7 ± 0.4 mmol/L (5.2 ± 1.1 mg/dL) during sevelamer hydrochloride tablet treatment. Sevelamer carbonate powder and sevelamer hydrochloride tablets are equivalent in controlling serum phosphorus; the geometric least square mean ratio was 0.95 (90% CI 0.87–1.03). No statistically significant or clinically meaningful differences were observed in calcium × phosphorus product and lipid levels between sevelamer carbonate powder and sevelamer hydrochloride tablets. Serum bicarbonate levels increased 2.7 ± 3.7 mmol/L (2.7 ± 3.7 mEq/L) during sevelamer carbonate treatment. No statistically significant change in bicarbonate was observed during sevelamer hydrochloride treatment. Sevelamer carbonate powder and sevelamer hydrochloride were well tolerated during this study. Conclusions. Sevelamer carbonate powder and sevelamer hydrochloride tablets are equivalent in controlling serum phosphorus and well tolerated in CKD patients on haemodialysis. Bicarbonate levels improved only during sevelamer carbonate treatment. Sevelamer carbonate powder should provide a welcomed new option for the treatment of hyperphosphataemia for CKD patients on dialysis.

A multicentric, international matched pair analysis of body composition in peritoneal dialysis versus haemodialysis patients

BACKGROUNDnVolume status, lean and fat tissue are gaining interest as prognostic predictors in patients on dialysis. Comparative data in peritoneal dialysis (PD) versus haemodialysis (HD) patients are lacking.nnnMETHODSnIn a cohort of PD (EuroBCM) and HD (Euclid database) patients, matched for country, gender, age and dialysis vintage, body composition was assessed by bioimpedance spectroscopy (BCM, Fresenius Medical Care). Time-averaged volume overload (TAVO) was defined as the mean of pre- and post-dialysis volume overload (VO), and relative (%) (TA)VO as (TA)VO/ECV.nnnRESULTSnFour hundred and ninety-one matched pairs (55.2% males, median age 60.0 years) were included. The body mass index (BMI, PD = 26.5 ± 4.7 versus HD = 25.9 ± 4.6 kg/m(2), P = 0.18 in males and 27.4 ± 5.8 versus 27.5 ± 6.6 kg/m(2), P = 0.75 in females) and fat tissue index (males: 11.5 ± 5.3 versus 11.4 ± 5.4 kg/m(2), P = 0.90, females: 14.8 ± 6.7 versus 15.4 ± 7.2 kg/m(2), P = 0.30) were not different in PD versus HD patients, whereas the lean tissue index (LTI) was higher in PD versus HD patients (males: 14.5 ± 3.4 versus 13.7 ± 3.1 kg/m(2), P = 0.001, females: 12.6 ± 3.3 versus 11.5 ± 2.6 kg/m(2), P < 0.0001). VO/extracellular water (ECW) was not different between PD versus just before the HD treatment (males: 10.8 ± 12.1 versus 9.2 ± 10.2%, P = 0.09; females: 6.5 ± 10.8 versus 7.7 ± 9.4%, P = 0.19). The relative TAVO was higher in PD versus HD (10.8 ± 12.1% versus 3.2 ± 11.2%, and 6.5 ± 10.8% versus 1.2 ± 10.9%, both P < 0.0001).nnnCONCLUSIONSnThe LTI was impaired, and this was more in males versus females, but was better preserved on PD versus HD, whereas fat tissue index (FTI) was increased, but not different between PD and HD. Volume overload was more present in PD versus HD when TAVO, but not when predialysis volume status, was used as a reference.

Estimation of residual glomerular filtration rate in peritoneal dialysis patients using cystatin C: comparison with 51Cr-EDTA clearance

BACKGROUNDnMeasuring glomerular filtration rate (GFR) is an important assessment in peritoneal dialysis patients. In clinical practice, it is commonly measured by calculating the mean of the urinary clearance of urea and creatinine (GFR(UrCl)) but this process is time consuming and unreliable. We wished to compare several estimates of GFR including residual GFR estimated from cystatin C (GFR(CysC)) using a published equation (Hoek), GFR(UrCl) and (51)Cr-ethylenediaminetetraacetic acid (EDTA) clearance, in peritoneal dialysis patients.nnnMETHODSnGFR(CysC), GFR(UrCl) and (51)Cr-EDTA clearance were measured in 28 patients undergoing peritoneal dialysis in a single dialysis unit.nnnRESULTSnGFR(CysC) was related to GFR(UrCl) (Spearmans rank correlation coefficient r(s) = 0.44; P = 0.0185) and to (51)Cr-EDTA clearance (r(s) = 0.48; P = 0.0099). GFR(CysC) values were significantly (P = 0.0077) lower than (51)Cr-EDTA clearance results (mean bias -19.7%). However, GFR(CysC) did not differ significantly (P > 0.05) from GFR(UrCl).nnnCONCLUSIONSnGFR(CysC) is related to GFR(UrCl) but has a significant negative bias against (51)Cr-EDTA. Given the known limitations of (51)Cr-EDTA in estimating GFR in renal failure, this study provides additional validation suggesting that cystatin C-estimated rGFR (GFR(CysC)) gives a reasonable estimation of GFR without the clinical problems associated with 24 h urine collections.

Plasma sodium and blood pressure in individuals on haemodialysis.

To study the relationship between pre-dialysis plasma sodium and blood pressure (BP), we performed an audit of patients who were on stable haemodialysis at St Bartholomews and The Royal London Hospital from 1 June 2009 to 15 June 2010. There were 651 patients with 7445 dialysis sessions where both plasma biochemistry and BP were measured before haemodialysis. We found a significant association between plasma sodium and both systolic and diastolic BP. A 1u2009mmolu2009l−1 increase in plasma sodium was related to 0.65/0.36u2009mmu2009Hg increase in BP (P<0.001 for both systolic and diastolic BP) after adjusting for potential confounding factors, including weight gain between dialyses and plasma albumin, both of which are crude indices of extracellular fluid volume. A separate analysis excluding individuals who were on BP treatment showed a similar relationship, with a 1-mmolu2009l−1 increase in plasma sodium associated with 0.82/0.56u2009mmu2009Hg increase in BP (P<0.001 for both, N=177). These results provide further support for the accumulating evidence that plasma sodium has an important role in regulating BP, which may be independent of extracellular volume. Our findings in conjunction with other evidence suggest that small changes in plasma sodium could be an important mechanism for the beneficial effects of lower dialysate sodium and lower salt intake on BP in haemodialysis patients.

Therapeutic Implications of Coexisting Severe Pulmonary Hemorrhage and Pulmonary Emboli in a Case of Wegener Granulomatosis

Wegener granulomatosis classically involves the renal, respiratory, and ear, nose, and throat systems. Pulmonary hemorrhage is recognized as a severe respiratory complication. Untreated, the mortality rate approaches 90% at 2 years. We describe a case of Wegener granulomatosis with coexistent severe lung hemorrhage and pulmonary and deep vein thromboses. A 31-year-old man presented with features of vasculitis, including epistaxis, fever, and acute kidney injury with an increased serum creatinine level (3.27 mg/dL). Kidney biopsy confirmed pauci-immune crescentic glomerulonephritis, and antineutrophil cytoplasmic antibody showing a cytoplasmic staining pattern was strongly positive. Standard immunosuppression therapy (prednisolone and cyclophosphamide) was started. Eleven days later, the patient developed sudden dyspnea. A computed tomographic pulmonary angiogram showed pulmonary emboli, and ultrasound of the limbs showed ileofemoral thrombi bilaterally. Subcutaneous enoxaparin and warfarin therapy was started, but 8 days later, the patient had a massive pulmonary hemorrhage. Anticoagulation therapy was stopped, and plasma exchange was started to prevent further life-threatening hemorrhage. An inferior vena cava filter was inserted to prevent further pulmonary emboli during the period when anticoagulation was withheld. Kidney function improved, and pulmonary hemorrhage resolved after 5 plasma exchanges. Reintroduction of intravenous heparin and subsequently warfarin caused no further bleeding. We discuss the difficult management dilemma this combination of disease manifestations presents and review the current literature.

CORRELATION OF PERISCREEN STRIP RESULTS AND WHITE CELL COUNT IN PERITONEAL DIALYSIS PERITONITIS

INTRODUCTIONnMonitoring of peritoneal dialysis (PD) peritonitis can be difficult for visually impaired patients. PeriScreen strips measure leukocyte esterase activity and this might be a useful objective test that can be performed by patients at home.nnnMETHODSnA prospective study of 138 episodes of peritonitis was undertaken. Effluent samples were analysed for white cell count (WCC) and PeriScreen score on days 3 and 5. Co-morbidity data were collated from these patients.nnnRESULTSnEffluent WCC and PeriScreen results were found to correlate with the gold standard assessment of microbiology WCC count. A positive PeriScreen result on day 5 predicted that the episode of peritonitis would relapse after treatment with a sensitivity of 80% but with a poor specificity of 45%. Patients who cleared or relapsed their peritonitis could not be differentiated based on their burden of co-morbidity, Karnofsky scores, age, dialysis vintage or infective organism.nnnCONCLUSIONnPeriScreen strip analysis correlated with microscopic WCC of PD. However, analysis of PD effluent on day 5 of treatment is not a good test to risk stratify patients for relapsing peritonitis.