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.

Simultaneous ipsilateral nephrectomy during kidney transplantation in autosomal dominant polycystic kidney disease: a matched pair analysis of 193 consecutive cases.

BACKGROUND: In end-stage renal transplant recipients with autosomal-dominant polycystic kidney disease (ADPKD), the imperative, optimal timing, and technique of native nephrectomy remains under discussion. The Freiburg Transplant Center routinely performs a simultaneous ipsilateral nephrectomy. METHODS: From April 1998 to May 2017, we retrospectively analyzed 193 consecutive ADPKD recipients, receiving per protocol simultaneous ipsilateral nephrectomy and compared morbidity, mortality, and outcome with 193 non-ADPKD recipients of a matched pair control. RESULTS: The incidence of surgical complications was similar with respect to severe medical, surgical, urological, vascular, and wound-related complications as well as reoperation rates and 30-day mortality. Intraoperative blood transfusions were required more often in the ADPKD (22.8%) compared with the control group (6.7%; p < 0.0001). Early postoperative urinary tract infections occurred more frequent (ADPKD 40.4%/control 29.0%; p = 0.0246). Time of surgery was prolonged by 30 min (ADPKD 169 min; 95%CI 159.8-175.6 min/control 139 min; 95%CI 131.4-145.0 min; p < 0.0001). One-year patient (ADPKD 96.4%/control 95.8%; p = 0.6537) and death-censored graft survival (ADPKD 94.8%/control 93.7%; p = 0.5479) were comparable between both groups. CONCLUSIONS: With respect to morbidity and mortality, per protocol, simultaneous native nephrectomy is a safe procedure. Especially in asymptomatic ADPKD KTx recipients, the number of total operations can be reduced and residual diuresis preserved up until transplantation. In living donation, even preemptive transplantation is possible.

Nocturnal Hemodialysis Compared with Conventional Dialysis for End-Stage Renal Disease Treatment in Polycystic Kidney Disease Patients.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cause of end-stage renal disease (ESRD). Little is known about outcomes after in-center nocturnal hemodialysis (NHD) treatment in ADPKD patients with ESRD. OBJECTIVES: This study aimed to evaluate the effects of in-center NHD compared with conventional hemodialysis (CHD) and peritoneal dialysis (PD) in ADPKD. METHODS: We used data of ADPKD adult patients with ESRD in the hospital database from 2000 to 2016. Propensity score matching, competing-risk regression, and Cox regression models were used for analysis. RESULTS: A total of 170 ADPKD patients were included. The median follow-up time was 5.5 years. In the overall multivariate-adjusted analysis, no significant difference of mortality risk was found in NHD vs. CHD (hazard ratio [HR] 1.33, 95% CI 0.26-6.73, p = 0.31) and PD (HR 1.06, 95% CI 0.14-7.71, p = 0.55), respectively. The overall survival rate also was not significantly different among the 3 groups (p = 0.88). Based on the propensity score, 26 patients on CHD and 26 patients on PD were successfully matched to 13 NHD patients. In the matched analysis, NHD was not associated with a lower risk of mortality compared with CHD (HR 2.14, 95% CI 0.33-14.00, p = 0.31) and PD (HR 0.68, 95% CI 0.52-8.94, p = 0.55). The result was similar when treating renal transplantation as a competing event. However, NHD was associated with a lower rate of complications (38.5 vs. 84.6%, p = 0.003) and a higher level of serum albumin (p < 0.001) compared with PD. CONCLUSIONS: NHD may not be a better choice in survival compared with conventional dialysis modalities for ADPKD patients in this pilot study. Patients in NHD have fewer complications than PD. Future studies with large sample sizes and longer follow-up are required.

Outcomes of patients with autosomal-dominant polycystic kidney disease on peritoneal dialysis: A meta-analysis.

BACKGROUND: Complications related to peritoneal dialysis (PD) in patients with autosomal-dominant polycystic kidney disease (ADPKD), including intraperitoneal rupture of renal cyst, hernia, membrane failure and peritonitis, have been reported. However, long-term clinical outcomes of ADPKD patients on PD remain unclear. We performed this meta-analysis to assess the risks of death, technique failure and peritonitis in ADPKD patients on PD. METHODS: A systematic review was conducted using MEDLINE, EMBASE and Cochrane databases from inception to October 2017 to identify studies that evaluated the outcomes of ADPKD patients on PD, including the risks of death, technique failure and peritonitis. Non-ADPKD patients on PD were used as controls. Effect estimates from the individual study were extracted and combined using the random-effect, generic inverse variance method of DerSimonian and Laird. RESULTS: Twelve cohort studies with a total of 14 673 patients on PD (931 ADPKD and 13 742 non-ADPKD patients) were enrolled. Compared with non-ADPKD status, ADPKD was associated with significantly decreased mortality risk with pooled odds ratio (OR) of 0.68 (95% confidence interval (CI), 0.53-0.86; I2 = 0). There were no associations of ADPKD with the risks of technique failure of PD and peritonitis with pooled OR of 0.93 (95% CI, 0.79-1.10; I2 = 0) and 0.88 (95% CI, 0.75-1.05; I2 = 0), respectively. We found no publication bias as assessed by Egger's regression asymmetry test, with P = 0.90, 0.28 and 0.60 for the risks of mortality, technique failure and peritonitis in ADPKD patients on PD, respectively. CONCLUSION: Compared with non-ADPKD patients on PD, our study demonstrates that ADPKD patients on PD have 0.68-fold decreased mortality risk. There are no associations of ADPKD status with the risks of technique failure or peritonitis.

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.

Noninvasive Immunohistochemical Diagnosis and Novel MUC1 Mutations Causing Autosomal Dominant Tubulointerstitial Kidney Disease.

BACKGROUND: Autosomal dominant tubulointerstitial kidney disease caused by mucin-1 gene (MUC1) mutations (ADTKD-MUC1) is characterized by progressive kidney failure. Genetic evaluation for ADTKD-MUC1 specifically tests for a cytosine duplication that creates a unique frameshift protein (MUC1fs). Our goal was to develop immunohistochemical methods to detect the MUC1fs created by the cytosine duplication and, possibly, by other similar frameshift mutations and to identify novel MUC1 mutations in individuals with positive immunohistochemical staining for the MUC1fs protein. METHODS: We performed MUC1fs immunostaining on urinary cell smears and various tissues from ADTKD-MUC1-positive and -negative controls as well as in individuals from 37 ADTKD families that were negative for mutations in known ADTKD genes. We used novel analytic methods to identify MUC1 frameshift mutations. RESULTS: After technique refinement, the sensitivity and specificity for MUC1fs immunostaining of urinary cell smears were 94.2% and 88.6%, respectively. Further genetic testing on 17 families with positive MUC1fs immunostaining revealed six families with five novel MUC1 frameshift mutations that all predict production of the identical MUC1fs protein. CONCLUSIONS: We developed a noninvasive immunohistochemical method to detect MUC1fs that, after further validation, may be useful in the future for diagnostic testing. Production of the MUC1fs protein may be central to the pathogenesis of ADTKD-MUC1.

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).

Background: Pathological features of autosomal dominant polycystic kidney disease (ADPKD) include enlarged kidney volume, higher frequency of digestive diverticulitis and abdominal wall hernias. Therefore, many nephrologists have concerns about the use of peritoneal dialysis (PD) in ADPKD patients. We aimed to analyse survival and technique failure in ADPKD patients treated with PD. Methods: We conducted two retrospective studies on patients starting dialysis between 2000 and 2010. We used two French registries: the French Renal Epidemiology and Information Network (REIN) and the French language Peritoneal Dialysis Registry (RDPLF). Using the REIN registry, we compared the clinical features and outcomes of ADPKD patients on PD (n = 638) with those of ADPKD patients on haemodialysis (HD) (n = 4653); with the RDPLF registry, those same parameters were determined for ADPKD patients on PD (n = 797) and compared with those of non-ADPKD patients on PD (n = 12 059). Results: A total of 5291 ADPKD patients and 12 059 non-ADPKD patients were included. Analysis of the REIN registry found that ADPKD patients treated with PD represented 10.91% of the ADPKD population. During the study period, PD was used for 11.2% of the non-ADPKD population. Compared with ADPKD patients on HD, ADPKD patients on PD had higher serum albumin levels (38.8 ± 5.3 versus 36.8 ± 5.7 g/dL, P < 0.0001) and were less frequently diabetic (5.31 versus 7.71%, P < 0.03). The use of PD in ADPKD patients was positively associated with the occurrence of a kidney transplantation but not with death [hazard ratio 1.15 (95% confidence interval 0.84-1.58)]. Analysis of the RDPLF registry found that compared with non-ADPKD patients on PD, ADPKD patients on PD were younger and had fewer comorbidities and better survival. ADPKD status was not associated with an increased risk of technique failure or an increased risk of peritonitis. Conclusions: According to our results, PD is proposed to a selected population of ADPKD patients, PD does not have a negative impact on ADPKD patients' overall survival and PD technique failure is not influenced by ADPKD status. Therefore PD is a reasonable option for ADPKD patients.

Clinical problems in hemodialysis patients with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a common monogenic disease characterized by massive enlargement of fluid-filled cysts in the kidney. Due to its genetic pattern, the disease differs from other CKD. ADPKD is a multi-system, progressive disorder which is frequently complicated with hypertension, cardiovascular events and cerebrovascular disease. Thus, there are many clinical problems specific to ADPKD. In this article, we reviewed these clinical problems and their management in ADPKD with hemodialysis patients.

A potentially crucial role of the PKD1 C-terminal tail in renal prognosis.

BACKGROUND: Autosomal dominant polycystic disease (ADPKD) often results in renal failure. Recently, allelic influences of PKD1 mutation types on renal survival were extensively investigated. Here, we analyzed integrated influences of PKD1 mutation types and positions on renal survival. METHODS: We included 338 (82 pedigrees) and 72 (12 pedigrees) patients with PKD1 and PKD2 mutations, respectively, identified through comprehensive gene analysis of 101 probands with ADPKD. Genetic testing was performed using next-generation sequencing, long-range PCR, and multiplex ligation-dependent probe amplification. Pathogenic mutations were identified by a software package-integrated seven databases and provided access to five cloud-based computing systems. RESULTS: Mean renal survivals of carriers with PKD1 non-truncating-type mutations at positions upstream of G-protein-coupled receptor proteolytic site (GPS-upstream domain), transmembrane domain, or cytoplasmic C-terminal tail (CTT) domain were 70.2, 67.0, and 50.1 years, respectively (P < 0.0001); renal survival was shorter for mutation positions closer to CTT domain, suggesting its crucial role in renal prognosis. Furthermore, in truncating-type mutations, strong inactivation is anticipated on nucleotides downstream from the mutation site, implying CTT domain inactivation irrespective of mutation site. Shorter mean renal survival was found for PKD1 truncating-type than non-truncating-type mutation carriers (P = 0.0348); mean renal survival was not different between PKD1 3'- and 5'-region truncating-type mutation carriers (P = 0.4375), but was shorter in PKD1 3'-region than in 5'-region non-truncating-type mutation carriers (P = 0.0014). Variable strength of CTT domain inactivation might account for these results. CONCLUSIONS: Aforementioned findings indicate that CTT domain's crucial role in renal prognosis needs further investigation by larger studies (ClinicalTrials.gov; NCT02322385).

Do metabolic derangements in end-stage polycystic kidney disease differ versus other primary kidney diseases?

AIM: Autosomal dominant polycystic kidney disease (ADPKD), a systemic disorder caused by mutation in genes encoding polycystins, has been reported to lead to metabolic derangements including new-onset diabetes mellitus after kidney transplantation. We analyzed markers of insulin resistance (IR), inflammation, nutritional status and insulin-like growth factor-1 (IGF-1) in end-stage renal disease (ESRD) patients with ADPKD and ESRD patients with other primary kidney diseases. METHODS: In a post hoc cross-sectional analysis in 254 non-diabetic CKD 5 patients starting on dialysis, glucose metabolism (insulin, IGF-1, homeostasis model assessment of IR, HOMA-IR), inflammation (high sensitivity C-reactive protein, interleukin-6, and tumour necrosis factor), nutritional status, and bone mineral density (BMD), were assessed. Survival was recorded for median time of 28 months (IQR 15-48 months). RESULTS: Neither indices of IR, nor IGF-1, inflammatory status, nutritional status, or BMD were different in patients with ADPKD as compared to other aetiologies of ESRD. Kaplan-Meier curves showed better survival among the ADPKD group versus other aetiologies, even after an exclusion of diabetic patients. CONCLUSIONS: The ESRD phenotype did not differ in ADPKD versus other primary kidney diseases in terms of markers of IR, inflammation, and nutritional status. This argues against the proposition that ADPKD patients are more prone to develop metabolic derangements beyond those generally observed in advanced CKD. However, additional studies are warranted to further elucidate systemic metabolic aspects of ADPKD.

Imaging classification of autosomal dominant polycystic kidney disease: a simple model for selecting patients for clinical trials.

The rate of renal disease progression varies widely among patients with autosomal dominant polycystic kidney disease (ADPKD), necessitating optimal patient selection for enrollment into clinical trials. Patients from the Mayo Clinic Translational PKD Center with ADPKD (n=590) with computed tomography/magnetic resonance images and three or more eGFR measurements over ≥6 months were classified radiologically as typical (n=538) or atypical (n=52). Total kidney volume (TKV) was measured using stereology (TKVs) and ellipsoid equation (TKVe). Typical patients were randomly partitioned into development and internal validation sets and subclassified according to height-adjusted TKV (HtTKV) ranges for age (1A-1E, in increasing order). Consortium for Radiologic Imaging Study of PKD (CRISP) participants (n=173) were used for external validation. TKVe correlated strongly with TKVs, without systematic underestimation or overestimation. A longitudinal mixed regression model to predict eGFR decline showed that log2HtTKV and age significantly interacted with time in typical patients, but not in atypical patients. When 1A-1E classifications were used instead of log2HtTKV, eGFR slopes were significantly different among subclasses and, except for 1A, different from those in healthy kidney donors. The equation derived from the development set predicted eGFR in both validation sets. The frequency of ESRD at 10 years increased from subclass 1A (2.4%) to 1E (66.9%) in the Mayo cohort and from 1C (2.2%) to 1E (22.3%) in the younger CRISP cohort. Class and subclass designations were stable. An easily applied classification of ADPKD based on HtTKV and age should optimize patient selection for enrollment into clinical trials and for treatment when one becomes available.

Intravascular embolization therapy in patients with enlarged polycystic liver.

BACKGROUND: Hepatic transcatheter arterial embolization (TAE) has become an accepted treatment option for patients with symptomatic autosomal dominant polycystic kidney disease (ADPKD) who also have polycystic liver disease and who are not good candidates for surgery. However, indications for TAE and long-term outcome with it are still unclear. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Symptomatic patients with ADPKD with polycystic liver disease who underwent hepatic TAE, June 2001 to December 2012, at Toranomon Hospital and whose liver volume data were available were studied (N=244; 56% on dialysis therapy, none with kidney transplants). Mean age was 55 ± 9 (SD) years, and mean liver volumes were 8,353 ± 2,807 and 6,626 ± 2,485 cm(3) in men and women, respectively. Target arteries were embolized from the periphery using platinum microcoils. PREDICTORS: Sex-specific quartiles (6,433, 8,142, and 9,574 cm(3) in men and 4,638, 6,078, and 8,181 cm(3) in women) of total liver volume pretreatment. OUTCOMES: All causes of mortality were obtained from medical records, followed up until July 31, 2013. MEASUREMENTS: Laboratory values were measured before TAE and 1, 3, 6, and 12 months after. Organ volumes were measured pretreatment, then 6 and 12 months after, by summing the products of the organ areas traced in each computed tomographic image. RESULTS: Liver/cyst volume decreased to 94.7% (95% CI, 93.5%-95.8%) at 6 months and 90.8% (95% CI, 88.7%-92.9%) at 12 months of pretreatment volumes. Serum protein and hematocrit values improved significantly without liver damage. Survival was significantly better for patients with liver volume ≤ 9,574 cm(3) (men) and ≤ 8,181 cm(3) (women) than for those with larger livers (5-year survival, 69% and 48%; P=0.02). Infection and liver failure caused most deaths, especially in patients with larger livers. LIMITATIONS: Referral bias and lack of control group. CONCLUSIONS: Hepatic TAE appears to be a safe and less invasive option for patients with symptomatic polycystic liver, especially those contraindicated for surgical treatment (eg, with malnutrition or on dialysis therapy), improving both hepatic volume and nutrition.

Renal replacement therapy for autosomal dominant polycystic kidney disease (ADPKD) in Europe: prevalence and survival--an analysis of data from the ERA-EDTA Registry.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the fourth most common renal disease requiring renal replacement therapy (RRT). Still, there are few epidemiological data on the prevalence of, and survival on RRT for ADPKD. METHODS: This study used data from the ERA-EDTA Registry on RRT prevalence and survival on RRT in 12 European countries with 208 million inhabitants. We studied four 5-year periods (1991-2010). Survival analysis was performed by the Kaplan-Meier method and by Cox proportional hazards regression. RESULTS: From the first to the last study period, the prevalence of RRT for ADPKD increased from 56.8 to 91.1 per million population (pmp). The percentage of prevalent RRT patients with ADPKD remained fairly stable at 9.8%. Two-year survival of ADPKD patients on RRT (adjusted for age, sex and country) increased significantly from 89.0 to 92.8%, and was higher than for non-ADPKD subjects. Improved survival was noted for all RRT modalities: haemodialysis [adjusted hazard ratio for mortality during the last versus first time period 0.75 (95% confidence interval 0.61-0.91), peritoneal dialysis 0.55 (0.38-0.80) and transplantation 0.52 (0.32-0.74)]. Cardiovascular mortality as a proportion of total mortality on RRT decreased more in ADPKD patients (from 53 to 29%), than in non-ADPKD patients (from 44 to 35%). Of note, the incidence rate of RRT for ADPKD remained relatively stable at 7.6 versus 8.3 pmp from the first to the last study period, which will be discussed in detail in a separate study. CONCLUSIONS: In ADPKD patients on RRT, survival has improved markedly, especially due to a decrease in cardiovascular mortality. This has led to a considerable increase in the number of ADPKD patients being treated with RRT.

Risk of intracranial hemorrhage associated with autosomal dominant polycystic kidney disease in patients with end stage renal disease.

BACKGROUND: An analysis of intracranial hemorrhage (ICH) in a national sample of autosomal dominant polycystic kidney disease (ADPKD) patients receiving long-term dialysis has not been reported. It is often assumed that patients with ADPKD are not at increased risk of ICH after starting dialysis. We hypothesized that patients with ADPKD would have a higher subsequent risk of ICH even after the start of chronic dialysis. METHODS: Retrospective cohort study of Medicare primary patients with and without ADPKD in the United States Renal Data System (USRDS), initiated on chronic dialysis or transplanted between 1 January 1999 and 3 July 2009, and followed until 31 December 2009. Covariates included age, gender, race, prior stroke, diabetes mellitus, dialysis modality, body mass index, serum albumin and other co-morbid conditions from the Medical Evidence Form. Primary outcome was ICH, based on inpatient and outpatient Medicare claims, and all-cause mortality. Kaplan-Meier analysis was used for unadjusted assessment of time to events. Cox regression was used for assessment of factors associated with ICH and mortality. We performed competing risk regression using kidney transplant and death as competing risks. Kidney transplant was also modeled as a time-dependent covariate in Cox regression. RESULTS: Competing risk regression demonstrated that ADPKD had a subhazard ratio 2.97 for ICH (95% CI 2.27-3.89). Adjusted Cox analysis showed that ADPKD patients had an AHR for death of 0.59 vs. non-ADPKD patients (95% CI 0.57-0.61). CONCLUSIONS: ADPKD is a significant risk factor for ICH among patients on maintenance dialysis. Our Medicare primary cohort was older than in previous studies of intracranial aneurysm rupture among ADPKD patients. There are also limitations inherent to using the USRDS database.

Hyperuricemia and deterioration of renal function in autosomal dominant polycystic kidney disease.

BACKGROUND: The role of hyperuricemia in disease progression of autosomal dominant polycystic kidney disease (ADPKD) has not been defined well. We investigated the association of serum uric acid (sUA) with renal function and the effect of hypouricemic treatment on the rate of renal function decline. METHODS: This is a single-center, retrospective, observational cohort study. A total of 365 patients with ADPKD who had estimated glomerular filtration rate (eGFR) ≥ 15 mL/min/1.73 m2 and who were followed up for > 1 year were included in our analysis. Hyperuricemia was defined by a sUA level of ≥ 7.0 mg/dL in male and ≥ 6.0 mg/dL in female or when hypouricemic medications were prescribed. RESULTS: Hyperuricemia was associated with reduced initial eGFR, independent of age, sex, hypertension, albuminuria, and total kidney volume. During a median follow-up period of over 6 years, patients with hyperuricemia showed a faster annual decline in eGFR (-6.3% per year vs. -0.9% per year, p = 0.008). However, after adjusting for age, sex, hypertension and initial eGFR, sUA was no longer associated with either annual eGFR decline or the development of ESRD. Among 53 patients who received hypouricemic treatment, the annual eGFR decline appeared to be attenuated after hypouricemic treatment (pretreatment vs. posttreatment: -5.3 ± 8. 2 vs. 0.2 ± 6.2 mL/min/1.73 m2 per year, p = 0.001 by Wilcoxon signed-rank test). CONCLUSIONS: Although hyperuricemia was associated with reduced eGFR, it was not an independent factor for renal progression in ADPKD. However, the correction of hyperuricemia may attenuate renal function decline in some patients with mild renal insufficiency.

One hundred consecutive kidney transplantations with simultaneous ipsilateral nephrectomy in patients with autosomal dominant polycystic kidney disease.

PURPOSE: Surgical management of autosomal dominant polycystic kidney disease (ADPKD) in patients awaiting renal transplantation is a challenging task. METHODS: From 1998 to 2009, a total of 100 consecutive renal transplantations with simultaneous unilateral nephrectomy were performed in 59 men and 41 women with ADPKD and end-stage renal failure. About 38% received kidney allografts from living donors. The ipsilateral polycystic kidney was removed at the time of renal transplantation. Immunosuppressive therapy was not modified. Cold ischaemia time was 155 (38-204 min) versus 910 min (95-2760 min) for living versus deceased donor transplantation. Mean weight of removed kidneys was 2002 g (414-8850 g). Mean follow-up was 3.0 years (0.8-10.0 years). RESULTS: Overall patient and graft survival were 97 and 96% at 1 year and 93 and 80% at 5 years, respectively. Serum creatinine at current follow-up was 1.49 (0.8-2.8) mg/dL. Surgical complications, which might be associated with simultaneous nephrectomy requiring re-operation, occurred in 12% (lymphocele 4%, hernia 4%, post-operative haematoma or bleeding 4%). None of the patients died peri-operatively. CONCLUSION: Renal transplantation with simultaneous unilateral nephrectomy in ADPKD is a reasonable procedure for patients suffering from massively enlarged native kidneys.

Renal replacement therapy in ADPKD patients: a 25-year survey based on the Catalan registry.

BACKGROUND: Some 7-10% of patients on replacement renal therapy (RRT) are receiving it because of autosomal dominant polycystic kidney disease (ADPKD). The age at initiation of RRT is expected to increase over time. METHODS: Clinical data of 1,586 patients (7.9%) with ADPKD and 18,447 (92.1%) patients with other nephropathies were analysed from 1984 through 2009 (1984-1991, 1992-1999 and 2000-2009). RESULTS: The age at initiation of RRT remained stable over the three periods in the ADPKD group (56.7 ± 10.9 (mean ± SD) vs 57.5 ± 12.1 vs 57.8 ± 13.3 years), whereas it increased significantly in the non-ADPKD group (from 54.8 ± 16.8 to 63.9 ± 16.3 years, p < 0.001). The ratio of males to females was higher for non-ADPKD than for ADPKD patients (1.6-1.8 vs 1.1-1.2). The prevalence of diabetes was significantly lower in the ADPKD group (6.76% vs 11.89%, p < 0.001), as were most of the co-morbidities studied, with the exception of hypertension. The survival rate of the ADPKD patients on RRT was higher than that of the non-ADPKD patients (p < 0.001). CONCLUSIONS: Over time neither changes in age nor alterations in male to female ratio have occurred among ADPKD patients who have started RRT, probably because of the impact of unmodifiable genetic factors in the absence of a specific treatment.

Survival after starting renal replacement treatment in patients with autosomal dominant polycystic kidney disease: a single-centre 40-year study.

BACKGROUND/AIMS: Adult polycystic kidney disease (ADPKD) has a predictable natural history and the relative lack of co-morbidity allows a relatively unconfounded assessment of survival. We examined whether survival on renal replacement treatment (RRT) has improved over the last four decades compared to that in the general population. METHODS: We conducted a retrospective cohort study of all patients with ADPKD who received RRT between 1971 and 2000 at the Oxford Kidney Unit. The main exposure was period of start of treatment (1971-1985 vs. 1986-2000) and the key outcome was overall survival. Standard Cox regression techniques were used to assess the association between these baseline variables and survival. RESULTS: Age at start of RRT (HR per 1 year 1.08; 95% CI 1.06-1.10) and presence of a functioning transplant (HR 0.22; 95% CI 0.16-0.31) were associated with improved survival in unadjusted analyses. After adjustment for age the period of treatment also became a significant predictor of overall survival (HR 0.67; 95% CI 0.47-0.97). CONCLUSIONS: Survival on RRT appears to have improved and exceeds that observed in the general population, such that RRT now provides almost two-thirds of the life expectancy of the general population, compared to about half in earlier decades.

[Outcome of renal transplantation in patients with autosomal dominant polycystic kidney disease]. / Resultados del trasplante renal en portadores de ríñones poliquísticos.

BACKGROUND: Patients with autosomal dominant polycystic kidney disease (ADPKD) have a better survival in chronic dialysis than patients with other etiologies of renal failure. It has been suggested that extra-renal manifestations of ADPKD may increase the odds of complications and mortality, if these patients are transplanted. AIM: To determine whether survival and complications in transplanted patients with ADPKD are different from kidney graft recipients with other etiologies of renal failure. SUBJECTS AND METHODS: Four hundred six patients with kidney transplantation were followed in three hospitals between 1976 and 2011 and 19 were carriers of ADPKD. The latter were matched by type of donor, gender, age and date of kidney transplant, with 38 graft recipients with other etiologies of renal failure. RESULTS: Graft and patient 1, 5, 10 and 15 years survival were similar in both groups. Hospitalizations due to viral infections and sepsis were more common in patients with ADPKD. There were no differences in the rate of acute rejection, delayed graft function, cancer, gastrointestinal disorders and hospitalizations due to cardiovascular diseases. The frequency of graft loss due to death with a functioning kidney was similar between both groups. CONCLUSIONS: Patient and graft survival in transplanted patients with ADPKD were similar to patients with other etiologies of renal failure. The rate and type of complications were similar between groups with the exception of hospitalizations due to sepsis and viral infections, which were more common in ADPKD patients.

Peritoneal dialysis as the first-line renal replacement therapy in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cause of kidney failure. Peritoneal dialysis (PD) often is avoided because of concerns about hernias and peritonitis. STUDY DESIGN: Retrospective matched-cohort study. SETTING & PARTICIPANTS: 42 consecutive patients with ADPKD and 84 nondiabetic patients matched by time of PD therapy initiation. PREDICTORS: ADPKD and comorbid conditions. OUTCOMES: Patient survival, technique survival, peritonitis-free survival; peritonitis rate; abdominal hernias. MEASUREMENTS: Dialysis adequacy and nutritional indexes; rate of decrease in residual renal function; bacteriologic cause of peritonitis. RESULTS: 5-year actuarial survival of the ADPKD and control groups was 71.0% and 69.7% (P = 0.4), whereas technique survival was 51.6% and 37.3%, respectively (P = 0.2). There was no difference in overall rates of peritonitis between the ADPKD and control groups (0.51 vs 0.53 episodes/patient-year; P = 0.3), and the incidence of Gram-negative peritonitis also was similar (0.16 vs 0.14 episodes/patient year; P = 0.5). Abdominal wall hernia was significantly more common in the ADPKD than control group (14 vs 6 cases; P < 0.001), but all patients were able to resume PD therapy after surgical repair. LIMITATIONS: Retrospective study with limited sample size. CONCLUSION: PD is a feasible treatment option for most patients with ADPKD with end-stage renal disease. Although patients with ADPKD have a higher risk of abdominal wall hernia, their overall survival rate and risk of peritonitis are similar to those of other nondiabetic PD patients.