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Bone histomorphometry for the diagnosis of renal osteodystrophy: a call for harmonization of reference ranges

Jørgensen, Hanne Skou ; Ferreira, Ana Carina ; D’Haese, Patrick ; [et al.]

Elsevier BV ; 2022

In: Kidney International Vol. 102, No. 2 ( 2022-08), p. 431-434

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In: Kidney International, Elsevier BV, Vol. 102, No. 2 ( 2022-08), p. 431-434

Type of Medium: Online Resource

ISSN: 0085-2538

URL: Article

DOI: 10.1016/j.kint.2022.04.030

Language: English

Publisher: Elsevier BV

Publication Date: 2022

detail.hit.zdb_id: 2007940-0

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Hilbrands, Luuk B ; Duivenvoorden, Raphaël ; Vart, Priya ; [et al.]

Oxford University Press (OUP) ; 2020

In: Nephrology Dialysis Transplantation Vol. 35, No. 11 ( 2020-11-01), p. 1973-1983

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In: Nephrology Dialysis Transplantation, Oxford University Press (OUP), Vol. 35, No. 11 ( 2020-11-01), p. 1973-1983

Abstract: Background. Patients on kidney replacement therapy comprise a vulnerable population and may be at increased risk of death from coronavirus disease 2019 (COVID-19). Currently, only limited data are available on outcomes in this patient population. Methods. We set up the ERACODA (European Renal Association COVID-19 Database) database, which is specifically designed to prospectively collect detailed data on kidney transplant and dialysis patients with COVID-19. For this analysis, patients were included who presented between 1 February and 1 May 2020 and had complete information available on the primary outcome parameter, 28-day mortality. Results. Of the 1073 patients enrolled, 305 (28%) were kidney transplant and 768 (72%) dialysis patients with a mean age of 60 ± 13 and 67 ± 14 years, respectively. The 28-day probability of death was 21.3% [95% confidence interval (95% CI) 14.3–30.2%] in kidney transplant and 25.0% (95% CI 20.2–30.0%) in dialysis patients. Mortality was primarily associated with advanced age in kidney transplant patients, and with age and frailty in dialysis patients. After adjusting for sex, age and frailty, in-hospital mortality did not significantly differ between transplant and dialysis patients [hazard ratio (HR) 0.81, 95% CI 0.59–1.10, P = 0.18] . In the subset of dialysis patients who were a candidate for transplantation (n = 148), 8 patients died within 28 days, as compared with 7 deaths in 23 patients who underwent a kidney transplantation & lt;1 year before presentation (HR adjusted for sex, age and frailty 0.20, 95% CI 0.07–0.56, P & lt; 0.01). Conclusions. The 28-day case-fatality rate is high in patients on kidney replacement therapy with COVID-19 and is primarily driven by the risk factors age and frailty. Furthermore, in the first year after kidney transplantation, patients may be at increased risk of COVID-19-related mortality as compared with dialysis patients on the waiting list for transplantation. This information is important in guiding clinical decision-making, and for informing the public and healthcare authorities on the COVID-19-related mortality risk in kidney transplant and dialysis patients.

Type of Medium: Online Resource

ISSN: 0931-0509 , 1460-2385

URL: Article

DOI: 10.1093/ndt/gfaa261

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2020

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3

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Goffin, Eric ; Candellier, Alexandre ; Vart, Priya ; [et al.]

Oxford University Press (OUP) ; 2021

In: Nephrology Dialysis Transplantation Vol. 36, No. 11 ( 2021-11-09), p. 2094-2105

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In: Nephrology Dialysis Transplantation, Oxford University Press (OUP), Vol. 36, No. 11 ( 2021-11-09), p. 2094-2105

Abstract: Coronavirus disease 2019 (COVID-19) has exposed haemodialysis (HD) patients and kidney transplant (KT) recipients to an unprecedented life-threatening infectious disease, raising concerns about kidney replacement therapy (KRT) strategy during the pandemic. This study investigated the association of the type of KRT with COVID-19 severity, adjusting for differences in individual characteristics. Methods Data on KT recipients and HD patients diagnosed with COVID-19 between 1 February 2020 and 1 December 2020 were retrieved from the European Renal Association COVID-19 Database. Cox regression models adjusted for age, sex, frailty and comorbidities were used to estimate hazard ratios (HRs) for 28-day mortality risk in all patients and in the subsets that were tested because of symptoms. Results A total of 1670 patients (496 functional KT and 1174 HD) were included; 16.9% of KT and 23.9% of HD patients died within 28 days of presentation. The unadjusted 28-day mortality risk was 33% lower in KT recipients compared with HD patients {HR 0.67 [95% confidence interval (CI) 0.52–0.85]}. In a fully adjusted model, the risk was 78% higher in KT recipients [HR 1.78 (95% CI 1.22–2.61)] compared with HD patients. This association was similar in patients tested because of symptoms [fully adjusted model HR 2.00 (95% CI 1.31–3.06)]. This risk was dramatically increased during the first post-transplant year. Results were similar for other endpoints (e.g. hospitalization, intensive care unit admission and mortality & gt;28 days) and across subgroups. Conclusions KT recipients had a greater risk of a more severe course of COVID-19 compared with HD patients, therefore they require specific infection mitigation strategies.

Type of Medium: Online Resource

ISSN: 0931-0509 , 1460-2385

URL: Article

DOI: 10.1093/ndt/gfab200

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2021

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Recovery of dialysis patients with COVID-19: health outcomes 3 months after diagnosis in ERACODA

Hemmelder, Marc H ; Noordzij, Marlies ; Vart, Priya ; [et al.]

Oxford University Press (OUP) ; 2022

In: Nephrology Dialysis Transplantation Vol. 37, No. 6 ( 2022-05-25), p. 1140-1151

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In: Nephrology Dialysis Transplantation, Oxford University Press (OUP), Vol. 37, No. 6 ( 2022-05-25), p. 1140-1151

Abstract: Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. Methods We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. Results In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8–6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. Conclusions Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis.

Type of Medium: Online Resource

ISSN: 0931-0509 , 1460-2385

URL: Article

DOI: 10.1093/ndt/gfac008

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2022

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The Clinical Frailty Scale as a triage tool for ICU admission of dialysis patients with COVID-19: an ERACODA analysis

Bouwmans, Pim ; Brandts, Lloyd ; Hilbrands, Luuk B ; [et al.]

Oxford University Press (OUP) ; 2022

In: Nephrology Dialysis Transplantation Vol. 37, No. 11 ( 2022-10-19), p. 2264-2274

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In: Nephrology Dialysis Transplantation, Oxford University Press (OUP), Vol. 37, No. 11 ( 2022-10-19), p. 2264-2274

Abstract: Several guidelines recommend using the Clinical Frailty Scale (CFS) for triage of critically ill coronavirus disease 2019 (COVID-19) patients. This study evaluates the impact of CFS on intensive care unit (ICU) admission rate and hospital and ICU mortality rates in hospitalized dialysis patients with COVID-19. Methods We analysed data of dialysis patients diagnosed with COVID-19 from the European Renal Association COVID-19 Database. The primary outcome was ICU admission rate and secondary outcomes were hospital and ICU mortality until 3 months after COVID-19 diagnosis. Cox regression analyses were performed to assess associations between CFS and outcomes. Results A total of 1501 dialysis patients were hospitalized due to COVID-19, of whom 219 (15%) were admitted to an ICU. The ICU admission rate was lowest (5%) in patients & gt;75 years of age with a CFS of 7–9 and highest (27%) in patients 65–75 years of age with a CFS of 5. A CFS of 7–9 was associated with a lower ICU admission rate than a CFS of 1–3 [relative risk 0.49 (95% confidence interval 0.27–0.87)]. Overall, mortality at 3 months was 34% in hospitalized patients, 65% in ICU-admitted patients and highest in patients & gt;75 years of age with a CFS of 7–9 (69%). Only 9% of patients with a CFS ≥6 survived after ICU admission. After adjustment for age and sex, each CFS category ≥4 was associated with higher hospital and ICU mortality compared with a CFS of 1–3. Conclusions Frail dialysis patients with COVID-19 were less frequently admitted to the ICU. Large differences in mortality rates between fit and frail patients suggest that the CFS may be a useful complementary triage tool for ICU admission in dialysis patients with COVID-19.

Type of Medium: Online Resource

ISSN: 0931-0509 , 1460-2385

URL: Article

DOI: 10.1093/ndt/gfac246

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2022

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Sex differences in COVID-19 mortality risk in patients on kidney function replacement therapy

Vart, Priya ; Duivenvoorden, Raphaël ; Adema, Aaltje ; [et al.]

Springer Science and Business Media LLC ; 2022

In: Scientific Reports Vol. 12, No. 1 ( 2022-10-26)

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In: Scientific Reports, Springer Science and Business Media LLC, Vol. 12, No. 1 ( 2022-10-26)

Abstract: In the general population with COVID-19, the male sex is an established risk factor for mortality, in part due to a more robust immune response to COVID-19 in women. Because patients on kidney function replacement therapy (KFRT) have an impaired immune response, especially kidney transplant recipients due to their use of immunosuppressants, we examined whether the male sex is still a risk factor for mortality among patients on KFRT with COVID-19. From the European Renal Association COVID-19 Database (ERACODA), we examined patients on KFRT with COVID-19 who presented between February 1st, 2020, and April 30th, 2021. 1204 kidney transplant recipients (male 62.0%, mean age 56.4 years) and 3206 dialysis patients (male 61.8%, mean age 67.7 years) were examined. Three-month mortality in kidney transplant recipients was 16.9% in males and 18.6% in females (p = 0.31) and in dialysis patients 27.1% in males and 21.9% in females (p = 0.001). The adjusted HR for the risk of 3-month mortality in males (vs females) was 0.89 (95% CI 65, 1.23, p = 0.49) in kidney transplant recipients and 1.33 (95% CI 1.13, 1.56, p = 0.001) in dialysis patients (p interaction = 0.02). In a fully adjusted model, the aHR for the risk of 3-month mortality in kidney transplant recipients (vs. dialysis patients) was 1.39 (95% CI 1.02, 1.89, p = 0.04) in males and 2.04 (95% CI 1.40, 2.97, p 〈 0.001) in females (p interaction = 0.02). In patients on KFRT with COVID-19, the male sex is not a risk factor for mortality among kidney transplant recipients but remains a risk factor among dialysis patients. The use of immunosuppressants in kidney transplant recipients, among other factors, may have narrowed the difference in the immune response to COVID-19 between men and women, and therefore reduced the sex difference in COVID-19 mortality risk.

Type of Medium: Online Resource

ISSN: 2045-2322

URL: Article

DOI: 10.1038/s41598-022-22657-4

Language: English

Publisher: Springer Science and Business Media LLC

Publication Date: 2022

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Clinical triage of patients on kidney replacement therapy presenting with COVID-19: an ERACODA registry analysis

Mitra, Sandip ; Jayanti, Anuradha ; Vart, Priya ; [et al.]

Oxford University Press (OUP) ; 2021

In: Nephrology Dialysis Transplantation Vol. 36, No. 12 ( 2021-12-02), p. 2308-2320

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In: Nephrology Dialysis Transplantation, Oxford University Press (OUP), Vol. 36, No. 12 ( 2021-12-02), p. 2308-2320

Abstract: Patients on kidney replacement therapy (KRT) are at very high risk of coronavirus disease 2019 (COVID-19). The triage pathway for KRT patients presenting to hospitals with varying severity of COVID-19 illness remains ill-defined. We studied the clinical characteristics of patients at initial and subsequent hospital presentations and the impact on patient outcomes. Methods The European Renal Association COVID-19 Database (ERACODA) was analysed for clinical and laboratory features of 1423 KRT patients with COVID-19 either hospitalized or non-hospitalized at initial triage and those re-presenting a second time. Predictors of outcomes (hospitalization, 28-day mortality) were then determined for all those not hospitalized at initial triage. Results Among 1423 KRT patients with COVID-19 [haemodialysis (HD), n = 1017; transplant, n = 406), 25% (n = 355) were not hospitalized at first presentation due to mild illness (30% HD, 13% transplant). Of the non-hospitalized patients, only 10% (n = 36) re-presented a second time, with a 5-day median interval between the two presentations (interquartile range 2–7 days). Patients who re-presented had worsening respiratory symptoms, a decrease in oxygen saturation (97% versus 90%) and an increase in C-reactive protein (26 versus 73 mg/L) and were older (72 vs 63 years) compared with those who did not return a second time. The 28-day mortality between early admission (at first presentation) and deferred admission (at second presentation) was not significantly different (29% versus 25%; P = 0.6). Older age, prior smoking history, higher clinical frailty score and self-reported shortness of breath at first presentation were identified as risk predictors of mortality when re-presenting after discharge at initial triage. Conclusions This study provides evidence that KRT patients with COVID-19 and mild illness can be managed effectively with supported outpatient care and with vigilance of respiratory symptoms, especially in those with risk factors for poor outcomes. Our findings support a risk-stratified clinical approach to admissions and discharges of KRT patients presenting with COVID-19 to aid clinical triage and optimize resource utilization during the ongoing pandemic.

Type of Medium: Online Resource

ISSN: 0931-0509 , 1460-2385

URL: Article

DOI: 10.1093/ndt/gfab196

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2021

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Association of obesity with 3-month mortality in kidney failure patients with COVID-19

Tantisattamo, Ekamol ; Imhof, Celine ; Jager, Kitty J ; [et al.]

Oxford University Press (OUP) ; 2022

In: Clinical Kidney Journal Vol. 15, No. 7 ( 2022-06-23), p. 1348-1360

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In: Clinical Kidney Journal, Oxford University Press (OUP), Vol. 15, No. 7 ( 2022-06-23), p. 1348-1360

Abstract: In the general population with coronavirus disease 2019 (COVID-19), obesity is associated with an increased risk of mortality. Given the typically observed obesity paradox among patients on kidney function replacement therapy (KFRT), especially dialysis patients, we examined the association of obesity with mortality among dialysis patients or living with a kidney transplant with COVID-19. Methods Data from the European Renal Association COVID-19 Database (ERACODA) were used. KFRT patients diagnosed with COVID-19 between 1 February 2020 and 31 January 2021 were included. The association of Quetelet's body mass index (BMI) (kg/m2), divided into: & lt;18.5 (lean), 18.5–24.9 (normal weight), 25–29.9 (overweight), 30–34.9 (obese I) and ≥35 (obese II/III), with 3-month mortality was investigated using Cox proportional-hazards regression analyses. Results In 3160 patients on KFRT (mean age: 65 years, male: 61%), 99 patients were lean, 1151 normal weight (reference), 1160 overweight, 525 obese I and 225 obese II/III. During follow-up of 3 months, 28, 20, 21, 23 and 27% of patients died in these categories, respectively. In the fully adjusted model, the hazard ratios (HRs) for 3-month mortality were 1.65 [95% confidence interval (CI): 1.10, 2.47], 1 (ref.), 1.07 (95% CI: 0.89, 1.28), 1.17 (95% CI: 0.93, 1.46) and 1.71 (95% CI: 1.27, 2.30), respectively. Results were similar among dialysis patients (N = 2343) and among those living with a kidney transplant (N = 817) (Pinteraction = 0.99), but differed by sex (Pinteraction = 0.019). In males, the HRs for the association of aforementioned BMI categories with 3-month mortality were 2.07 (95% CI: 1.22, 3.52), 1 (ref.), 0.97 (95% CI: 0.78. 1.21), 0.99 (95% CI: 0.74, 1.33) and 1.22 (95% CI: 0.78, 1.91), respectively, and in females corresponding HRs were 1.34 (95% CI: 0.70, 2.57), 1 (ref.), 1.31 (95% CI: 0.94, 1.85), 1.54 (95% CI: 1.05, 2.26) and 2.49 (95% CI: 1.62, 3.84), respectively. Conclusion In KFRT patients with COVID-19, on dialysis or a kidney transplant, obesity is associated with an increased risk of mortality at 3 months. This is in contrast to the obesity paradox generally observed in dialysis patients. Additional studies are required to corroborate the sex difference in the association of obesity with mortality.

Type of Medium: Online Resource

ISSN: 2048-8505 , 2048-8513

URL: Article

DOI: 10.1093/ckj/sfac083

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2022

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Strategies to prevent SARS-CoV-2 transmission in hemodialysis centres across Europe—lessons for the future

Noordzij, Marlies ; Meijers, Björn ; Gansevoort, Ron T ; [et al.]

Oxford University Press (OUP) ; 2023

In: Clinical Kidney Journal Vol. 16, No. 4 ( 2023-03-30), p. 662-675

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In: Clinical Kidney Journal, Oxford University Press (OUP), Vol. 16, No. 4 ( 2023-03-30), p. 662-675

Abstract: Early reports on the pandemic nature of coronavirus disease 2019 (COVID-19) directed the nephrology community to develop infection prevention and control (IPC) guidance. We aimed to make an inventory of strategies that dialysis centres followed to prevent infection with COVID-19 in the first pandemic wave. Methods We analyzed IPC measures taken by hemodialysis centres treating patients presenting with COVID-19 between 1 March 2020 and 31 July 2020 and that completed the European Renal Association COVID-19 Database centre questionnaire. Additionally, we made an inventory of guidelines published in European countries to prevent spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in dialysis centres. Results Data from 73 dialysis units located in and bordering Europe were analyzed. All participating centres implemented IPC measures to mitigate the impact of SARS-CoV-2 during the first pandemic wave. Measures mentioned most often included triage with questions before entering the dialysis ward, measuring body temperature, hand disinfection, masking for all patients and staff, and personal protective equipment for staff members. These measures were also recommended in most of the 14 guidelines that were identified in the inventory of national guidelines and were also scored as being among the most important measures by the authors of this paper. Heterogeneity existed between centres and national guidelines regarding the minimal distance between dialysis chairs and recommendations regarding isolation and cohorting. Conclusions Although variation existed, measures to prevent transmission of SARS-CoV-2 were relatively similar across centres and national guidelines. Further research is needed to assess causal relationships between measures taken and spread of SARS-CoV-2.

Type of Medium: Online Resource

ISSN: 2048-8505 , 2048-8513

URL: Article

DOI: 10.1093/ckj/sfac253

Language: English

Publisher: Oxford University Press (OUP)

Publication Date: 2023

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A Novel Rat Model of Vitamin D Deficiency: Safe and Rapid Induction of Vitamin D and Calcitriol Deficiency without Hyperparathyroidism

Stavenuiter, Andrea W. D. ; Arcidiacono, Maria Vittoria ; Ferrantelli, Evelina ; [et al.]

Hindawi Limited ; 2015

In: BioMed Research International Vol. 2015 ( 2015), p. 1-5

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In: BioMed Research International, Hindawi Limited, Vol. 2015 ( 2015), p. 1-5

Abstract: Vitamin D deficiency is associated with a range of clinical disorders. To study the mechanisms involved and improve treatments, animal models are tremendously useful. Current vitamin D deficient rat models have important practical limitations, including time requirements when using, exclusively, a vitamin D deficient diet. More importantly, induction of hypovitaminosis D causes significant fluctuations in parathyroid hormone (PTH) and mineral levels, complicating the interpretation of study results. To overcome these shortcomings, we report the successful induction of vitamin D deficiency within three weeks, with stable serum PTH and minerals levels, in Wistar rats. We incorporated two additional manoeuvres compared to a conventional diet. Firstly, the vitamin D depleted diet is calcium (Ca) enriched, to attenuate the development of secondary hyperparathyroidism. Secondly, six intraperitoneal injections of paricalcitol during the first two weeks are given to induce the rapid degradation of circulating vitamin D metabolites. After three weeks, serum 25-hydroxyvitamin D 3 (25D) and 1,25-dihydroxyvitamin D 3 (1,25D) levels had dropped below detection limits, with unchanged serum PTH, Ca, and phosphate (P) levels. Therefore, this model provides a useful tool to examine the sole effect of hypovitaminosis D, in a wide range of research settings, without confounding changes in PTH, Ca, and P.

Type of Medium: Online Resource

ISSN: 2314-6133 , 2314-6141

URL: Article

DOI: 10.1155/2015/604275

Language: English

Publisher: Hindawi Limited

Publication Date: 2015

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