Outcome of autosomal dominant polycystic kidney disease patients on peritoneal dialysis: a national retrospective study based on two French registries (the French Language Peritoneal Dialysis Registry and the French Renal Epidemiology and Information Network)

An update on absolute and relative indications for dialysis treatment modalities

Background

Choosing a dialysis modality is an important decision for people to make as their kidney failure progresses. In doing so, their options should be informed by any absolute or relative indications that may favour one modality over another.

Methods

In creating this update, we reviewed literature using a framework that considered first, high-level outcomes (survival and modality transition) from large registry data and cohort studies when considering optimal patient pathways; second, factors at a dialysis provider level that might affect relative indications; and third, specific patient-level factors. Both main types of dialysis modality, peritoneal (PD) and haemodialysis (HD), and their subtypes were considered.

Results

For most people starting dialysis, survival is independent of modality, including those with diabetes. Better survival is seen in those with less comorbidity starting with PD or home HD, reflecting continued improvements over recent decades that have been greater than improvements seen for centre HD. There are provider-level differences in the perceived relative indications for home dialysis that appear to reflect variability in experience, prejudice, enthusiasm, and support for patients and carers. Absolute contraindications are uncommon and, in most cases, where modality prejudice exists, e.g. obesity, Adult Polycystic Kidney Disease, and social factors, this is not supported by reported outcomes.

Conclusion

Absolute contraindications to a particular dialysis modality are rare. Relative indications for or against particular modalities should be considered but are rarely more important than patient preferences.

Dialysis and Transplant Considerations in Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is the fourth leading cause of kidney replacement therapy. Unfortunately, the need for dialysis or kidney transplantation is a foreseeable outcome for many patients affected by ADPKD. We review some of the unique issues that should be considered in the management of patients with ADPKD who require dialysis or kidney transplantation. The choice of dialysis modality may be influenced by the enlarged kidneys and liver, but peritoneal dialysis should not be excluded as an option, as studies do not consistently show that there is an increased risk for technique failure or peritonitis. The optimal kidney replacement therapy option remains kidney transplantation; however, nephrectomy may be needed if there is insufficient space for the allograft. Living donor candidates from at-risk families need to be excluded from carrying the disease either by diagnostic imaging criteria or genetic testing. Other potential transplant issues, such as malignancy and cardiovascular and metabolic risks, should also be recognized. Despite these issues, patients with ADPKD requiring dialysis or kidney transplantation generally have more favorable outcomes as compared to those with other causes of chronic kidney disease. Further studies are still needed to personalize the therapeutic approach for those receiving kidney replacement therapy and eventually improve clinical outcomes.

Dialysis-network variability in home dialysis use not explained by patient characteristics: a national registry-based cohort study in France

Background

Although associated with better quality of life and potential economic advantages, home dialysis use varies greatly internationally and appears to be underused in many countries. This study aimed to estimate the dialysis-network variability in home dialysis use and identify factors associated with 1) the uptake in home dialysis, 2) the proportion of time spent on home dialysis and 3) home dialysis survival (patient and technique).

Methods

All adults ≥ 18 years old who had dialysis treatment during 2017-2019 in mainland France were included. Mixed-effects regression models were built to explore factors including patient or residence characteristics and dialysis network associated with variation in home dialysis use.

Results

During 2017-2019, 7 728/78 757 (9.8%) patients underwent dialysis at least once at home for a total of 120 594/ 1 508 000 (8%) months. The heterogeneity at the dialysis-network level and to a lesser extent the regional level regarding home dialysis uptake or total time spent was marginally explained by patient characteristics or residence and dialysis-network factors. Between-network heterogeneity was less for patient and technique survival. These results were similar when the analysis was restricted to home peritoneal dialysis or home hemodialysis.

Conclusions

Variability between networks in the use of home dialysis was not fully explained by non-modifiable patient and residence characteristics. Our results suggest that to increase home dialysis use in France, one should focus on home dialysis uptake rather than survival. Financial incentives and a quality improvement program should be implemented at the dialysis-network level to increase home dialysis use.

An Unusual Case of Recurrent Migration of the Peritoneal Dialysis Catheter into the Inguinal Hernia Sac

We herein report the first case of a patient with recurrent migration of the peritoneal dialysis (PD) catheter into the inguinal hernia sac. A 58-year-old man suffered from end-stage renal disease due to polycystic kidney disease (PKD). A year before starting PD, a PD catheter was implanted with stepwise initiation of PD using the Moncrief-Popovich technique. He complained of drain failure and right inguinal swelling during the induction period and was diagnosed with right inguinal hernia. Further examination revealed that the PD catheter tip had migrated into the inguinal hernia sac. Although surgery was planned, the PD catheter tip spontaneously migrated back into the intra-peritoneal space. 14 months later, he noticed fill and drain failure again. Diagnosis was PD catheter dysfunction due to migration into the right inguinal hernia sac. PD was resumed without issues after repositioning of the PD catheter and repair of the inguinal hernia. Inguinal hernia is a frequent complication in PD patients, especially in those with PKD. Early diagnosis and treatment of hernia should be considered in PD patients.

Peritoneal dialysis patient selection from a comorbidity perspective

Despite many medical and socioeconomic advantages, peritoneal dialysis (PD) is an underutilized dialysis modality that in most countries is used by only 5%-20% of dialysis patients, while the vast majority are treated with in-center hemodialysis. Several factors may explain this paradox, such as lack of experience and infrastructure for training and monitoring of PD patients, organizational issues, overcapacity of hemodialysis facilities, and lack of economic incentives for dialysis centers to use PD instead of HD. In addition, medical conditions that are perceived (rightly or wrongly) as contraindications to PD represent barriers for the use of PD because of their purported potential negative impact on clinical outcomes in patients starting PD. While there are few absolute contraindications to PD, high age, comorbidities such as diabetes mellitus, obesity, polycystic kidney disease, heart failure, and previous history of abdominal surgery and renal allograft failure, may be seen (rightly or wrongly) as relative contraindications and thus barriers to initiation of PD. In this brief review, we discuss how the presence of these conditions may influence the strategy of selecting patients for PD, focusing on measures that can be taken to overcome potential problems.

Identification of the Factors Associated With Intraperitoneal Pressure in ADPKD Patients Treated With Peritoneal Dialysis

Introduction

Peritoneal dialysis (PD) is reported to be underused in the autosomal dominant polycystic kidney disease (ADPKD) population because doctors fear technical failure caused by reduced abdominal space and high intraperitoneal pressure (IPP).

Methods

We designed a multicenter retrospective study to be carried out in 15 French centers recruiting 60 patients with ADPKD treated with PD to identify factors associated with IPP. Inclusion criteria were start of PD between 2010 and 2017, available tomodensitometry, and IPP measurement in the first year of dialysis. The clinical and radiological data for each patient were reviewed by the same operator. Total kidney volume (TKV), liver volume, and the volume of the abdominal cavity were measured using contouring.

Results

TKV and the volume of the abdominal cavity in women and men were, respectively, 2397 ml versus 3758 ml and 9402 ml versus 12,920 ml. In the univariate analysis, IPP was significantly and positively associated with body surface area (P = 0.0024), body mass index (BMI) (P < 0.0001), the volume of the abdominal cavity (P = 0.0005), and the volume of the dialysate infused in the peritoneal cavity (IPV) (P = 0.0108). In the multivariate analysis, only BMI was still significantly associated with IPP (P = 0.0004)

Conclusions

Our results identified BMI as the main factor linked to IPP in patients with ADPKD. Despite a reliable assessment of the volume of their organs we did not find any correlation between liver and kidney volumes and IPP. To our knowledge, this is the first study designed to identify factors associated with IPP in patients with ADPKD on PD.

Unilateral nephrectomy versus renal arterial embolization and technique survival in peritoneal dialysis patients with autosomal dominant polycystic kidney disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder associated with progressive enlargement of the kidneys and liver. ADPKD patients may require renal volume reduction, especially before renal transplantation. The standard treatment is unilateral nephrectomy. However, surgery incurs a risk of blood transfusion and alloimmunization. Furthermore, when patients are treated with peritoneal dialysis (PD), surgery is associated with an increased risk of temporary or definitive switch to haemodialysis (HD). Unilateral renal arterial embolization can be used as an alternative approach to nephrectomy.

METHODS

We performed a multicentre retrospective study to compare the technique of survival of PD after transcatheter renal artery embolization with that of nephrectomy in an ADPKD population. We included ADPKD patients treated with PD submitted to renal volume reduction by either surgery or arterial embolization. Secondary objectives were to compare the frequency and duration of a temporary switch to HD in both groups and the impact of the procedure on PD adequacy parameters.

RESULTS

More than 700 patient files from 12 centres were screened. Only 37 patients met the inclusion criteria (i.e. treated with PD at the time of renal volume reduction) and were included in the study (21 embolized and 16 nephrectomized). Permanent switch to HD was observed in 6 embolized patients (28.6%) versus 11 nephrectomized patients (68.8%) (P = 0.0001). Renal artery embolization was associated with better technique survival: subdistribution hazard ratio (SHR) 0.29 [95% confidence interval (CI) 0.12-0.75; P = 0.01]. By multivariate analysis, renal volume reduction by embolization and male gender were associated with a decreased risk of switching to HD. After embolization, a decrease in PD adequacy parameters was observed but no embolized patients required temporary HD; the duration of hospitalization was significantly lower [5 days [interquartile range (IQR) 4.0-6.0] in the embolization group versus 8.5 days (IQR 6.0-11.0) in the surgery group.

CONCLUSIONS

Transcatheter renal artery embolization yields better technique survival of PD in ADPKD patients requiring renal volume reduction.

Different Effects of Iron Indices on Mortality in Patients With Autosomal Dominant Polycystic Kidney Disease After Long-Term Hemodialysis: A Nationwide Population-Based Study

OBJECTIVE

Iron supplementation and erythropoietin stimulating agents (ESAs) are essential for maintaining hemoglobin levels in hemodialysis patients. However, patients with autosomal-dominant polycystic kidney disease (PKD) have higher endogenous erythropoietin levels, so their recommended iron indices for hemodialysis patients may differ. This study evaluated iron profiles, including ferritin levels and transferrin saturation (TSAT) to identify factors affecting mortality in patients on dialysis, and those associated with mortality in patients with and without PKD.

DESIGN

This cohort study from the Taiwan Renal Registry Data System stratified mortality risk by the presence of PKD recorded as the underlying disease.

SUBJECTS

We enrolled 1346 hemodialysis patients with PKD and 82,873 hemodialysis patients without PKD.

MAIN OUTCOME MEASURE

The primary outcome was 3-year all-cause mortality. Predictors included time-averaged and baseline serum ferritin levels and TSAT. Multivariate Cox regression analysis adjusting for age, comorbidities, and relevant laboratory parameters was used to estimate the all-cause hazard ratios (HRs) for mortality.

RESULTS

The mean ages of patients with and without PKD were 56.2±13.2 and 61.7±13.5 years and the median follow-up time was 37 (15-76) months. The adjusted mortality risks for time-averaged ferritin levels >800 ng/mL (HR=1.52; 95% confidence interval: 1.40-1.65) or TSAT levels >50% (HR=1.46; 95% confidence interval: 1.30-1.65) were significantly higher among patients without PKD than those for patients with normal iron indices. However, a U-shaped curve of mortality against ferritin/TSAT levels was not observed in patients with PKD. In the sensitivity test, there was no difference among PKD patients who underwent regular ESA therapy and those who did not.

CONCLUSION

Iron indices have different effects on mortality among patients with and without PKD. Iron supplementation, recommended serum ferritin levels, or TSAT should be monitored in hemodialysis patients, especially those without PKD. Clinicians should consider treating anemia in hemodialysis patients individually, especially in PKD.