Factors influencing kidney transplantation rates: a study from the ERA Registry

BACKGROUND

Large international differences exist in kidney transplantation (KT) rates. We aimed to investigate which factors may explain the total, deceased donor, and living donor KT rates over the last decade.

METHODS

KT experts from 39 European countries completed the Kidney Transplantation Rate Survey on measures and barriers and their potential effect on the KT rate in their country. In the analyses, countries were divided into low, middle, and high KT rate countries based on the KT rate at the start of study period in 2010.

RESULTS

Experts from low KT rate countries reported more frequently to have taken measures regarding staff, equipment and facilities to increase total KT rate compared with middle and high KT rate countries. For donor type specific KT, the largest international differences in measures taken were reported for deceased donor KT, with middle and high KT rate countries taking more measures, such as the use of expanded criteria donor kidneys, the presence of transplantation coordinators, and (inter)national exchange of donor kidneys. Once a measure was taken, experts' opinion on its success was similar across the low, middle and high KT rate countries. Experts from low KT rate countries more often reported potential barriers, such as patients' lack of knowledge and distrust in the health care system.

CONCLUSIONS

In particular in low KT rate countries, KT rate might be stimulated by optimizing staff, equipment, and facilities. In addition, all countries may benefit from deceased and living donor specific measures.

Evaluation of Expanded Criteria Donors Using the Kidney Donor Profile Index and the Preimplantation Renal Biopsy

The increasing comorbidity of kidney transplant (KT) donors make it necessary to develop scores to correctly assess the quality of kidney grafts. This study analyzes the usefulness of the preimplantation biopsy and the Kidney Donor Profile Index (KDPI) as indicators of KT survival from expanded criteria donors (ECD). Retrospective study of KT in our center between January 2010 to June 2019 who received a kidney from an ECD and underwent a preimplantation biopsy. 266 KT were included. Graft survival was categorized by KDPI quartiles: Q1 = 86%, Q2 = 95%, Q3 = 99% and Q4 = 100%. KT from KDPI Q1 presented better survival (p = 0.003) and Q4 donors had worse renal function (p = 0.018) and poorer glomerular filtration rate (3rd month; p = 0.017, 1st year; p = 0.010). KT survival was analyzed according to KDPI quartile and preimplantation biopsy score simultaneously: Q1 donors with biopsy score ≤3 had the best survival, especially comparing against Q3 with a biopsy score >3 and Q4 donors (p = 0.014). In multivariable analysis, hyaline arteriopathy, glomerulosclerosis, and KDPI Q4 were predictors for graft survival. High KDPI and a greater histological injury in the preimplantation biopsy, especially glomerular and vascular lesions, were related to a higher rate of KT loss from ECD.

Acute kidney injury, urinary and histopathological disorders in kidney transplant patients with SARS-CoV2 infection

Background

Acute kidney injury (AKI) is a manifestation of SARS-CoV-2 infection. The evidence in kidney transplant (KT) is limited, as there are scarce data about the histologic features in graft biopsies of these patients.

Material and Methods

A retrospective cohort study of KTs with SARS-CoV-2 infection from August 28, 2020, to April 23, 2021. We collected the incidence of AKI and the presence of urinary and histopathological disorders. Both groups were compared (AKI vs no AKI). Immunohistochemical and reverse transcription-polymerase chain reaction studies were performed on the anatomopathological samples.

Results

In our study, 72 KTs had SARS-CoV-2 infection and, among them, 27 patients (35.1%) developed AKI related to increased severity and a worse evolution of the infection, defined by a greater presence of pneumonia (P < .001), hospitalization (P < .001), admission to the intensive care unit (P < .001), the need for ventilation support (P < .001), and continuous renal replacement therapy (P < .001). In the multivariable analysis, pneumonia behaved as an independent predictor for AKI development (P = .046). No differences were observed between proteinuria a month before and after infection (P = .224). In addition, 5 patients showed microhematuria and 2 patients presented transient glycosuria without hyperglycemia. Of the 5 kidney biopsies performed, 1 biopsy (20%) showed positive reverse transcription polymerase chain reaction for SARS-CoV-2.

Conclusions

AKI is a frequent and potentially serious complication in KT patients. Occasionally it could be accompanied by abnormalities in the urinary sediment. Of 5 biopsied patients, 1 patient had positive reverse transcription polymerase chain reaction in renal tissue, which suggests the systemic spread of the virus and the tropism for the renal graft.

Clinical Presentation and Determinants of Mortality of Invasive Pulmonary Aspergillosis in Kidney Transplant Recipients: A Multinational Cohort Study

The prognostic factors and optimal therapy for invasive pulmonary aspergillosis (IPA) after kidney transplantation (KT) remain poorly studied. We included in this multinational retrospective study 112 recipients diagnosed with probable (75.0% of cases) or proven (25.0%) IPA between 2000 and 2013. The median interval from transplantation to diagnosis was 230 days. Cough, fever, and expectoration were the most common symptoms at presentation. Bilateral pulmonary involvement was observed in 63.6% of cases. Positivity rates for the galactomannan assay in serum and bronchoalveolar lavage samples were 61.3% and 57.1%, respectively. Aspergillus fumigatus was the most commonly identified species. Six- and 12-week survival rates were 68.8% and 60.7%, respectively, and 22.1% of survivors experienced graft loss. Occurrence of IPA within the first 6 months (hazard ratio [HR]: 2.29; p-value = 0.027) and bilateral involvement at diagnosis (HR: 3.00; p-value = 0.017) were independent predictors for 6-week all-cause mortality, whereas the initial use of a voriconazole-based regimen showed a protective effect (HR: 0.34; p-value = 0.007). The administration of antifungal combination therapy had no apparent impact on outcome. In conclusion, IPA entails a dismal prognosis among KT recipients. Maintaining a low clinical suspicion threshold is key to achieve a prompt diagnosis and to initiate voriconazole therapy.

Risk Factors Associated With Early Invasive Pulmonary Aspergillosis in Kidney Transplant Recipients: Results From a Multinational Matched Case-Control Study

Risk factors for invasive pulmonary aspergillosis (IPA) after kidney transplantation have been poorly explored. We performed a multinational case-control study that included 51 kidney transplant (KT) recipients diagnosed with early (first 180 posttransplant days) IPA at 19 institutions between 2000 and 2013. Control recipients were matched (1:1 ratio) by center and date of transplantation. Overall mortality among cases was 60.8%, and 25.0% of living recipients experienced graft loss. Pretransplant diagnosis of chronic pulmonary obstructive disease (COPD; odds ratio [OR]: 9.96; 95% confidence interval [CI]: 1.09-90.58; p = 0.041) and delayed graft function (OR: 3.40; 95% CI: 1.08-10.73; p = 0.037) were identified as independent risk factors for IPA among those variables already available in the immediate peritransplant period. The development of bloodstream infection (OR: 18.76; 95% CI: 1.04-339.37; p = 0.047) and acute graft rejection (OR: 40.73, 95% CI: 3.63-456.98; p = 0.003) within the 3 mo prior to the diagnosis of IPA acted as risk factors during the subsequent period. In conclusion, pretransplant COPD, impaired graft function and the occurrence of serious posttransplant infections may be useful to identify KT recipients at the highest risk of early IPA. Future studies should explore the potential benefit of antimold prophylaxis in this group.

A form of apolipoprotein a-I is found specifically in relapses of focal segmental glomerulosclerosis following transplantation

Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) following kidney transplantation occurs in a large percentage of patients. Accurate prediction of recurrence and elucidation of its pathogenesis are major therapeutic goals. To detect differential proteins related to FSGS recurrence, proteomic analysis was performed on plasma and urine samples from 35 transplanted idiopathic FSGS patients, divided into relapsing and nonrelapsing. Several proteins were detected increased in urine of relapsing FSGS patients, including a high molecular weight form of apolipoprotein A-I, named ApoA-Ib, found exclusively in relapsing patients. This finding was verified by Western blot individually in the 35 patients and validated in an independent group of 40 patients with relapsing or nonrelapsing FSGS, plus two additional groups: FSGS-unrelated patients showing different proteinuria levels (n = 30), and familial FSGS transplanted patients (n = 14). In the total of 119 patients studied, the ApoA-Ib form was detected in 13 of the 14 relapsing FSGS patients, and in one of the 61 nonrelapsing patients. Only one of the 30 patients with FSGS-unrelated proteinuria tested positive for ApoA-Ib, and was not detected in familial patients. Urinary ApoA-Ib is associated with relapses in idiopathic FSGS and warrants additional investigation to determine its usefulness as biomarker of relapse following transplantation.

Efficacy and safety of conversion from twice-daily to once-daily tacrolimus in a large cohort of stable kidney transplant recipients

Prolonged-release tacrolimus was developed to provide a more convenient once-daily dosing that could improve patient adherence. We conducted a multicenter, prospective, observational, 12-month study to describe the efficacy, safety and patient preference of conversion from tacrolimus twice-daily to once-daily formulation in stable kidney transplant recipients in routine clinical practice. Conversion was made on a 1 mg: 1 mg basis (1 mg: 1.1 mg in patients with trough levels <6 ng/mL). The study included 1832 patients (mean age (± SD): 50.0 ± 13.4 years; 62.7% male). After conversion, a modest reduction in tacrolimus trough levels, necessitating an increase in daily dose, was observed (mean changes at 12 months of -9.1% and +1.24%, respectively; p < 0.0001). Mean glomerular filtration rate did not change significantly (56.5 ± 19.7 mL/min at conversion vs. 55.7 ± 20.6 mL/min at 12 months). Proteinuria, blood pressure, lipid, hepatic and glucose parameters remained stable. Eight patients (0.4%) had acute rejection and 34 patients (1.85%) discontinued treatment. Almost all patients (99.4%) preferred the once-daily formulation, because of less frequent dosing (66%) and improved adherence (34%). In conclusion, at similar doses to twice-daily tacrolimus, once-daily formulation provided stable renal function, a low acute rejection rate, and good tolerability in stable kidney transplant recipients in the routine clinical practice setting.

[Daclizumab in combination with mycophenolate mofetil and a late introduction of Tacrolimus at low doses, as a therapeutic approach in the elderly renal transplant donor-recipients pairs in kidney transplant]

BACKGROUND

Nowadays, it is more frequent the use of kidneys from older donors in the renal transplantation. Moreover, it is also increasing the age of the recipients due to the ageing of the population treated with hemodialysis. This makes that recipients become older more commonly. This situation raises specific problems in the renal graft and in the recipient as well. In this manuscript we present the results of a multicenter study that analyzed an immunosuppressive strategy specifically designed to elderly renal transplant donor-recipients.

METHODS

Patients > or =50 years were transplanted from donors > or =55 years. Immunosuppressive strategy consisted of daclizumab (2 doses of 1mg/Kg) in combination with steroids, mycophenolate mofetil (2g/daily during the first 45 days and then adjusted according to local practice) and Tacrolimus. Tacrolimus was introduced between 5 and 7 day post-transplantation, adjusting the predose levels between 4-8 ng/mL. Mean follow-up was 12 months.

RESULTS

A total of 133 patients were included in the study. Mean age of recipients and donors was 61.3+/-6.2 years and 64.4+/-5.3, respectively. 42.9% of patients needed dialysis during the first week (median 4 days). Between first month and first year, serum creatinine improved from 2.0+/-1.0 mg/dl to 1.5+/-0.4 mg/dl. Similar improvements were observed when creatinine clearance (Cockroft-Gault) was calculated. The survival of patient and renal graft at 12 months was 97.7% and 96.1%, respectively. The acute rejection rate was 13.5%. Security profile was good, as expected.

CONCLUSIONS

The Daclizumab and mycophenolate mofetil regimen with a late introduction of Tacrolimus at low doses is a good alternative in the elderly renal transplant recipients with a low immunologic risk.

Detection and treatment of post kidney transplant hyperglycemia: a Spanish multicenter cross-sectional study

INTRODUCTION

The prevalence of diabetes mellitus (DM) is greater among patients with solid organ transplants than in the general population, although the factors associated with posttransplant DM (PTDM) are unknown.

OBJECTIVES

The objective of this study was to estimate the prevalence of and assess the risk factors for PTDM.

PATIENTS AND METHODS

We included outpatients with functioning isolated solid organ allografts (kidney, liver, heart, and lung). We collected demographic and posttransplant clinical data that included DM diagnostic ADA criteria, DM treatment, DM family history, presence of hepatitis C virus (HCV), immunosuppression treatment, hypertension, and dyslipidemia.

RESULTS

A total of 2178 patients included, 1410 kidney recipients, 489 liver transplants, 207 heart transplants, and 72 lung recipients. Seventeen and four-tenths percent of the patients who did not have DM prior to transplantation, developed PTDM (median time: 79 days). A greater prevalence was observed among patients with a family history, HCV, and tacrolimus treatment (with or without steroids P < .05). By logistic regression analyses, OR for these factors were 1.51, 1.65, and 1.38, respectively. Of those patients who did not suffer PTDM, 55.2% showed basal blood glucose values under 100 mg/dL; only 68% presented with a hemoglobin Alc under 6.

CONCLUSIONS

The prevalence of PTDM among kidney recipients was higher than that in the general population. DM family history, HCV positive, and tacrolimus were risk factors associated with this entity.

[Renal transplantation in HIV-infected patients in Spain]

HIV infection has experienced dramatic improvement in morbidity and mortality with the highly active antiretroviral therapy (HAART). This prompted a reevaluation of organ-solid transplantation as a treatment option for HIV-infected patients. Some trials in the United States have shown that one- and 2-year graft and patient survival is comparable to HIV-negative transplant population. In Europe the experience is still scarce. The aim of this study is to analyse the outcome and the clinical characteristics of HIV-infected patients who received kidney transplantation in Spain in the HAART era. Ten patients were transplanted in our country since 2001. Only one patient was black. The main cause of end-stage renal disease reported was glomerulonephritis. Six of the recipients were coinfected by hepatitis C virus. Inclusion criteria included undetectable HIV viral load and CD4 counts greater than 200/pL. Immunosuppression consisted of steroids, tacrolimus and mycophenolate mofetil, with antibody induction in 4 cases. The median and mean follow-up was 11 and 16.3+/-15.6 (3-46) months, respectively. One recipient lost his graft because of early renal venous thrombosis. The remaining patients are functioning graft with mean serum creatinina level of 1.5 +/- 0.5 mg/dl. Biopsy-proven acute rejection was diagnosed in 4 recipients and was reversed in all cases with antirejection treatment. The plasma HIV RNA levels have remained controlled and CD4 counts have been stable in excess of 200 cell/microL. None of patients have developed AIDS complications. Recipients receiving protease inhibitor-based HAART regimens required significant dosing modification to maintain appropriate tacrolimus levels. Our results show that renal transplantation can be a safe and effective treatment in select HIV-infected patients. Like other series, the acute rejection rate was higher than in non-HIV recipients. The reasons of this rejection incidence remain unknown.

Efficacy of Conversion to Sirolimus in Posttransplantation Kaposi’s Sarcoma

The increased incidence of Kaposi's sarcoma (KS) in organ transplantation has been related to the KS herpes virus and the permissive effect of immunosuppressive therapy. We postulated that conversion to SRL in renal recipients with KS favored regression of KS lesions without increasing the risk of graft rejection.

METHODS

In this study we performed a retrospective chart review of 7 caucasian renal transplant recipients affected by KS to determine demographic data, etiology of ESRD, immunologic risk factors, immunosuppressive treatment, KS disease follow-up, and renal function before and after SRL conversion.

RESULTS

All seven patients were under calcineurin inhibitor treatment at the onset of KS which was limited to the skin, without regression despite attempts to minimize immunosuppression. After conversion to SRL, six patients showed progressive regression of KS lesions, with only hyperpigmented atrophic cutaneous lesions remaining after a mean time of 8.1 months (2-18 months). The seventh patient has completed 9 months follow-up with a near complete regression of KS lesions. One patient returned to hemodialysis after 13 months following irreversible acute renal failure not directly related to SRL conversion; in the other six, renal function was stable. The mean serum creatinine was 1.87 +/- 0.64 versus 1.74 +/- 0.68 mg/dL, pre-conversion versus the end of follow up, respectively. Mean SRL blood level was 9.2 +/- 2.0 ng/mL.

CONCLUSION

After SRL conversion, patients with KS showed progressive regression without an increased risk of acute rejection. SRL offers a promising approach to the management of posttransplantation KS and probably other malignancies in organ transplant recipients.

Two doses of daclizumab with delayed introduction of low-dose tacrolimus in elderly recipients of cadaveric renal transplants from donors >55 years of age

BACKGROUND

Renal transplants from elderly donors have a high incidence of delayed graft function, which can be increased by the initial use of calcineurin inhibitors. Our purpose was to assess the safety and efficacy of an immunosuppressive regimen using anti-IL-2R antibodies and MMF that allows delayed introduction of low-dose tacrolimus using elderly donors to elderly recipients.

METHODS

This observational study involved 13 transplant centers. In total there were 119 patients (age 60.5 +/- 6.6 years, range 50 to 77) who received a kidney from a donor of mean age 64 +/- 5 years (range 55 to 76), 94% of whom died from a CVA. Immunosuppression consisted of daclizumab (1 mg/kg in two doses; preoperatively and on day 14) combined with steroids, mycophenolate mofetil (initial dose of 2 g/d), and tacrolimus (0.1 mg/kg per day). Tacrolimus was introduced before day 7 (mean 5.5 days) and adjusted to a target level of 5 to 8 ng/mL. The mean follow-up was 8 months.

RESULTS

Two grafts were lost due to primary nonfunction and acute rejection and 48 patients (40%) required dialysis due to delayed graft function, although it was generally of short duration (median 4 days; only 2 cases >2 weeks). Acute rejection occurred in 16 patients (13.4%), of whom 13 were biopsy-confirmed (10.9%; Banff 1997 grades I and II). Three patients withdrew from the study, and three died (sepsis, accident, and cardiovascular event). The remaining 111 patients continued follow-up, with a median creatinine value of 1.5 mg/dL at 12-months. Eighty-six percent of patients had at least one episode of infection, half of which were urinary tract infections. There were 16 cases of CMV infection.

CONCLUSIONS

Based on the initial results, our immunosuppressive regimen seems to offer good short-term renal function while maintaining an acceptable rejection rate and a low incidence of serious infections.

Treatment with adefovir dipivoxil in a renal transplant patient with renal insufficiency and lamivudine-resistant hepatitis B infection

Lamivudine is a safe, effective treatment for hepatitis B virus (HBV) reactivation after renal transplantation. However, prolonged lamivudine therapy can produce resistance to the drug. Adefovir dipivoxil (ADV) has demonstrated efficacy in patients with lamivudine resistance, but there is limited clinical experience in patients with either renal transplants or severe renal insufficiency. A 47-year-old man with asymptomatic HBV infection underwent renal transplantation in November 1995. In September 2000 lamivudine therapy was initiated to treat HBV reactivation. The outcome was good, with negative HBV DNA levels. Two years later, significant viral replication developed again. At that time the patient already had advanced renal insufficiency due to chronic graft nephropathy. The transaminase levels were increased, and the HBV DNA reached greater than 200,000 copies/mL by polymerase chain reaction, with development of ascites and cirrhosis. The patient was started on ADV 10 mg every 72 hours (dose adjusted to renal function). There was rapid normalization of hepatic enzymes and progressive decline of the viral load. HBV DNA became negative after 6 months of ADV treatment. The renal function has since remained stable. This case suggests that ADV can be safe and effective in the treatment of renal transplant patients with lamivudine-resistant hepatitis B, even in the presence of advanced renal insufficiency.

Effect of Parathyroidectomy on Renal Graft Function

Some authors have reported acute impairment of renal transplant function after parathyroidectomy (PTx). Since 1996 PTx has been performed in 22 renal transplant recipients (follow-up, 24.2 +/- 15 months; serum creatinine concentration (SCr) pre-PTx, 1.26 +/- 0.4 mg/dL). We analyzed the serum levels of immunoreactive parathyroid hormone, calcitriol, calcium, phosphate, alkaline phosphatase, SCr, and hemoglobin, as well as proteinuria, blood pressure, and immunosuppressive treatment at several times: before PTx and at 7 days, 1 month, and then every 3 months post-PTx. After PTx we observed acute renal function deterioration until the third post-PTx month, when SCr levels returned to baseline values. We found no changes in blood pressure, although there was a trend toward a reduced dosage of antihypertensive drugs. We compared the patients who showed more significant increases (>30% from baseline) in SCr (group A, n = 7) with those who did not (group B, n = 15). Group A had higher SCr levels pre-PTx. We observed no other significant differences, either pre-PTx or post-PTx. In 2 patients in group A, SCr returned to baseline at the third month after PTx, but in the other 5 the renal function impairment persisted. Taking into account this risk and that severe hyperparathyroidism does not revert after transplantation, it would seem more appropriate in such cases to perform PTx while the patient is on the waiting list. The causes of this renal functional impairment are not clear, but the patients who showed worse deterioration also had a worse renal function pre-PTx.

Compressive myelopathy due to dialysis-associated amyloidosis

A 66-year-old woman presented a spastic quadriparesis due to compression of the cervical cord 6 years after the beginning of chronic hemodialysis. Five years later, she developed a second episode of compressive myelopathy affecting the lumbar spine. On both occasions, surgical laminectomy with removal of fibroligamentous rings that compressed the cord led to a total recovery of the patient. Histological study demonstrated the presence of massive amyloid deposits in the surgically excised material.

Chronic renal insufficiency after an episode of macroscopic hematuria in IgA nephropathy

Several cases of acute renal failure associated with episodes of macroscopic hematuria (EMH) in IgA nephropathy (IgAN) have been reported; in every case renal function returned to normal. We report 2 cases with previous normal renal function that developed acute renal failure during EMH of 17 and 30 days duration, respectively. Renal biopsies showed mesangial proliferation with IgA deposits, crescents in 10-15% of glomeruli and a marked tubular necrosis with red blood cell casts obstructing the lumen in 30-45% of tubules. Although renal function improved after EMH cessation, it did not recover previous normal values. Thus, EMH can produce permanent loss of renal function in patients with IgAN.

Cholesterol embolism to the skin

The clinical features of a patient with cholesterol embolism are presented. Histopathological examination showed the typical clefts of cholesterol in the skin and renal vessels. We believe this entity is under-reported in the dermatological literature.

Nephrotic syndrome and focal glomerulosclerosis in adult polycystic kidney disease

We report a 35-year-old man with adult polycystic kidney disease (APKD) that developed nephroptic syndrome accompanied by a rapid worsening of renal function. Histologic examination showed marked tubulointerstitial chronic abnormalities and focal glomerulosclerosis (FGS) lesions in 24% of the glomeruli. With captopril, an renal function continued to deteriorate. No other cases of nephrotic-range proteinuria were detected among 65 APKD patients with renal insufficiency. Histologic examination of an other 12 kidneys removed from patients with APKD showed striking interstitial lesions, most of the glomeruli being normal. However, those patients with higher amounts of proteinuria had more glomeruli (14-32%) with FGS lesions.

Tubular dysfunction in nephrotic syndrome: incidence and prognostic implications

Although some cases of tubular dysfunction (TD) associated with nephrotic syndrome have been described, the incidence and the characteristics of this complication remain unknown. We investigated the presence of TD (renal glycosuria, aminoaciduria, metabolic acidosis with normal anion gap, hypouricaemia, and throughout hypophosphataemia) in 36 patients with nephrotic syndrome. Ten patients (group 1) showed glycosuria at some time during the course of their illness, ranging from 2.5 to 11.2 g/24 h. In addition, seven of them had metabolic acidosis with normal anion gap, five aminoaciduria, and two hypouricaemia. Membranous glomerulonephritis was the most frequent aetiology in group 1 patients (7 of 10). Proteinuria and serum creatinine (SCr) were significantly higher in group 1 patients than in the 26 remaining patients without TD (group 2): 10.2 +/- 3.7 versus 6.7 +/- 2.9 g/24 h (P less than 0.01) and 3.2 +/- 1.9 versus 1.6 +/- 0.9 mg/dl (P less than 0.05) respectively. The appearance of TD coincided with a clear worsening of renal function in most of group 1 patients. In addition, at the end of follow-up, SCr had increased from 3.2 +/- 1.9 to 5.6 +/- 3.3 mg/dl (P less than 0.05) in this group. In contrast, SCr did not show significant changes in group 2 (1.6 +/- 0.9 versus 2.1 +/- 2.2 mg/dl). In conclusion, a significant proportion (27.7%) of patients with nephrotic syndrome present TD data at some moment of their course; the appearance of this complication appears to be a sign of poor prognosis.