The Minnesota attributable risk of kidney donation (MARKD) study: a retrospective cohort study of long-term (> 50 year) outcomes after kidney donation compared to well-matched healthy controls.

BACKGROUND: There is uncertainty about the long-term risks of living kidney donation. Well-designed studies with controls well-matched on risk factors for kidney disease are needed to understand the attributable risks of kidney donation. METHODS: The goal of the Minnesota Attributable Risk of Kidney Donation (MARKD) study is to compare the long-term (> 50 years) outcomes of living donors (LDs) to contemporary and geographically similar controls that are well-matched on health status. University of Minnesota (n = 4022; 1st transplant: 1963) and Mayo Clinic LDs (n = 3035; 1st transplant: 1963) will be matched to Rochester Epidemiology Project (REP) controls (approximately 4 controls to 1 donor) on the basis of age, sex, and race/ethnicity. The REP controls are a well-defined population, with detailed medical record data linked between all providers in Olmsted and surrounding counties, that come from the same geographic region and era (early 1960s to present) as the donors. Controls will be carefully selected to have health status acceptable for donation on the index date (date their matched donor donated). Further refinement of the control group will include confirmed kidney health (e.g., normal serum creatinine and/or no proteinuria) and matching (on index date) of body mass index, smoking history, family history of chronic kidney disease, and blood pressure. Outcomes will be ascertained from national registries (National Death Index and United States Renal Data System) and a new survey administered to both donors and controls; the data will be supplemented by prior surveys and medical record review of donors and REP controls. The outcomes to be compared are all-cause mortality, end-stage kidney disease, cardiovascular disease and mortality, estimated glomerular filtration rate (eGFR) trajectory and chronic kidney disease, pregnancy risks, and development of diseases that frequently lead to chronic kidney disease (e.g. hypertension, diabetes, and obesity). We will additionally evaluate whether the risk of donation differs based on baseline characteristics. DISCUSSION: Our study will provide a comprehensive assessment of long-term living donor risk to inform candidate living donors, and to inform the follow-up and care of current living donors.

Kidney Transplantation in Patients With Monoclonal Gammopathy of Renal Significance (MGRS)-Associated Lesions: A Case Series.

RATIONALE & OBJECTIVE: Data on kidney transplantation outcomes among patients with monoclonal gammopathy of renal significance (MGRS) are lacking. STUDY DESIGN: Case series of patients with MGRS, some of whom received clone-directed therapies before kidney transplantation. SETTING & PARTICIPANTS: 28 patients who underwent kidney transplantation from 1987 through 2016 after diagnosis with MGRS-associated lesions including light-chain deposition disease (LCDD), C3 glomerulopathy with monoclonal gammopathy (C3G-MG), and light-chain proximal tubulopathy (LCPT). FINDINGS: Of the 19 patients with LCDD, 10 were treated before kidney transplantation and 9 were treatment-naive. Among the treated patients with LCDD, 3 (30%) experienced histologic recurrence, 2 (20%) grafts failed, and 2 (20%) died during a median follow-up of 70 (range, 3-162) months after transplant. In the treatment-naive LCDD group, 8 (89%) had histologic recurrence, 6 (67%) grafts failed, and 4 (44%) patients died during a median follow-up of 60 (range, 35-117) months. Of the 5 patients who had a complete response before transplant, none died, and only 1 experienced graft failure, 162 months after transplant. Of 5 patients with C3G-MG, 3 were treatment-naive before transplant. Both patients who were treated before transplant had histologic recurrence, and 1 experienced graft failure and died. Among the 3 patients with treatment-naive C3G-MG, histologic recurrence occurred in all, and graft loss and death were observed in 2 and 1, respectively. In the LCPT group (n=4), histologic recurrence was observed in all 3 patients who did not receive clone-directed therapies before transplant, and 2 of these patients died, 1 with a functioning kidney. The 1 patient with LCPT who received therapy before transplant did not have histologic recurrence or graft loss and survived. LIMITATIONS: Small sample size, nonstandardized clinical management, retrospective design. CONCLUSIONS: Recurrence is very common in all MGRS-associated lesions after kidney transplant. Achieving a complete hematologic response may reduce the risks of recurrence, graft loss, and death. More studies are needed to determine the effects of hematologic response on outcomes for each MGRS-associated lesion.

Renal function outcomes and kidney biopsy features of living kidney donors with hypertension.

BACKGROUND: The medium- to long-term outcomes of living kidney donors with hypertension compared to normotensive donors are not well understood, especially with the recent changes in hypertension guidelines. METHODS: We studied a cohort of 950 living kidney donors using different definitions of hypertension based on either ≥140/90 or ≥130/80 mmHg thresholds and based on either office or ambulatory blood pressure readings. Microstructural features on kidney biopsy at the time of donation were compared using different definitions of hypertension. RESULTS: After adjusting for years of follow-up, age, sex, and baseline eGFR, hypertension (by any definition) did not significantly predict an eGFR < 45 ml/min/1.73 m2 at a median follow-up of 10 years postdonation, though there was a borderline association with ambulatory blood pressure ≥ 130/80 mmHg predicting a 40% decline in eGFR (OR = 1.53, 1.00-2.36; p = .051). Proteinuria was predicted by office blood pressure ≥ 140/90 mmHg and by nondipper profile on nocturnal ambulatory blood pressure measurements. At the time of donation, larger glomeruli and arterial hyalinosis on biopsy were associated with hypertension defined by either ≥140/90 or ≥130/80 mmHg (by office or ambulatory measurements). Nocturnal nondipper status was associated with larger glomeruli size but not arteriolar hyalinosis when compared to dippers. CONCLUSIONS: In programs that accept donors with controlled hypertension, various definitions of hypertension are associated with histological findings in the donated kidney, but none predict a clinically significant decline in kidney function 10 years after donation. These data support allowing healthy individuals with controlled hypertension to donate a kidney. However, donors with office hypertension (≥140/90 mmHg) and nondippers (regardless of hypertension status) are at greater long-term risk for proteinuria, and particularly for these donors, longer follow-up is warranted.

Kidney Structural Features from Living Donors Predict Graft Failure in the Recipient.

BACKGROUND: Nephrosclerosis, nephron size, and nephron number vary among kidneys transplanted from living donors. However, whether these structural features predict kidney transplant recipient outcomes is unclear. METHODS: Our study used computed tomography (CT) and implantation biopsy to investigate donated kidney features as predictors of death-censored graft failure at three transplant centers participating in the Aging Kidney Anatomy study. We used global glomerulosclerosis, interstitial fibrosis/tubular atrophy, artery luminal stenosis, and arteriolar hyalinosis to measure nephrosclerosis; mean glomerular volume, cortex volume per glomerulus, and mean cross-sectional tubular area to measure nephron size; and calculations from CT cortical volume and glomerular density on biopsy to assess nephron number. We also determined the death-censored risk of graft failure with each structural feature after adjusting for the predictive clinical characteristics of donor and recipient. RESULTS: The analysis involved 2293 donor-recipient pairs. Mean recipient follow-up was 6.3 years, during which 287 death-censored graft failures and 424 deaths occurred. Factors that predicted death-censored graft failure independent of both donor and recipient clinical characteristics included interstitial fibrosis/tubular atrophy, larger cortical nephron size (but not nephron number), and smaller medullary volume. In a subset with 12 biopsy section slides, arteriolar hyalinosis also predicted death-censored graft failure. CONCLUSIONS: Subclinical nephrosclerosis, larger cortical nephron size, and smaller medullary volume in healthy donors modestly predict death-censored graft failure in the recipient, independent of donor or recipient clinical characteristics. These findings provide insights into a graft's "intrinsic quality" at the time of donation, and further support the use of intraoperative biopsies to identify kidney grafts that are at higher risk for failure.

Larger nephron size, low nephron number, and nephrosclerosis on biopsy as predictors of kidney function after donating a kidney.

It is unclear whether structural findings in the kidneys of living kidney donors predict postdonation kidney function. We studied living kidney donors who had a kidney biopsy during donation. Nephron size was measured by glomerular volume, cortex volume per glomerulus, and mean cross-sectional tubular area. Age-specific thresholds were defined for low nephron number (calculated from CT and biopsy measures) and nephrosclerosis (global glomerulosclerosis, interstitial fibrosis/tubular atrophy, and arteriosclerosis). These structural measures were assessed as predictors of postdonation measured GFR, 24-hour urine albumin, and hypertension. Analyses were adjusted for baseline age, gender, body mass index, systolic and diastolic blood pressure, hypertension, measured GFR, urine albumin, living related donor status, and time since donation. Of 2673 donors, 1334 returned for a follow-up visit at a median 4.4 months after donation, with measured GFR <60 mL/min/1.73 m2 in 34%, urine albumin >5 mg/24 h in 13%, and hypertension in 5.3%. Larger glomerular volume and interstitial fibrosis/tubular atrophy predicted follow-up measured GFR <60 mL/min/1.73 m2 . Larger cortex volume per glomerulus and low nephron number predicted follow-up urine albumin >5 mg/24 h. Arteriosclerosis predicted hypertension. Microstructural findings predict GFR <60 mL/min/1.73 m2 , modest increases in urine albumin, and hypertension shortly after kidney donation.

Weight gain after kidney donation: Association with increased risks of type 2 diabetes and hypertension.

In the general population, obesity is associated with an increased risk of developing hypertension (HTN), type 2 diabetes mellitus (DM), and end-stage renal disease (ESRD). Therefore, most transplant centers have a body mass index (BMI) threshold for accepting living kidney donors. But there have been no studies of postdonation weight gain trends and any associated risks. We tracked serial BMIs in 940 donors for a median (IQ range) follow-up of 22.3 (15.4-35.8) years. We studied the impact of postdonation weight gain in a model adjusted for family history of HTN or DM. Donor characteristics included age, sex, smoking, fasting blood glucose, eGFR, systolic and diastolic BP, and BMI at time of donation and time postdonation. Postdonation weight gain was associated with a significant increase in the relative risk of developing HTN RR 1.93 (95% CI 1.51-2.46) (P < 0.001) and/or DM RR 4.18 (95% CI 2.05-8.5) (P < 0.0001), but not (to date) cardiovascular disease (CVD), reduced eGFR or death. Like the general population, donors gained weight as they aged; a higher BMI was associated with higher incidence of DM and HTN. Postdonation care should include ongoing counseling on the risks of substantial weight gain.

Renal Function Profile in White Kidney Donors: The First 4 Decades.

Previous studies reported the risk of ESRD after kidney donation, but not the renal outcomes that precede ESRD. Here, we estimated the risk of proteinuria, reduced GFR, and ESRD in 3956 white kidney donors, assessed the contribution of postdonation hypertension and diabetes to these outcomes, and developed a risk calculator. After a mean±SD follow-up of 16.6±11.9 years, 215 (6.1%) donors developed proteinuria. Men had a higher risk of proteinuria (hazard ratio [HR], 1.56; 95% confidence interval [95% CI], 1.18 to 2.05; P<0.001) as did those with higher body mass index (HR, 1.10; 95% CI, 1.06 to 1.13; P<0.001). In all, 1410 (36%) donors reached an eGFR<60 ml/min per 1.73 m(2), and 112 (2.8%) donors had either an eGFR<30 ml/min per 1.73 m(2) or ESRD (28 donors developed ESRD). An eGFR<30 ml/min per 1.73 m(2) or ESRD associated with older age (HR, 1.07; 95% CI, 1.05 to 1.09; P<0.001), higher body mass index (HR, 1.08; 95% CI, 1.04 to 1.13; P<0.001), and higher systolic BP (HR, 1.02; 95% CI, 1.00 to 1.04; P=0.01) at donation. Postdonation diabetes and hypertension associated with a fourfold higher risk of proteinuria and a >2-fold higher risk of ESRD. Models predicting proteinuria and reduced eGFR performed well (C-index 0.77-1.00). In conclusion, severe reduction in GFR and ESRD after kidney donation were uncommon and were highly associated with postdonation diabetes and hypertension. Furthermore, information available before donation may predict long-term renal outcomes in white living kidney donors.

Outcomes of kidney retransplantation in recipients with prior post-transplant lymphoproliferative disorder.

Post-transplant lymphoproliferative disease (PTLD) is an uncommon but serious complication of solid organ transplantation. Reduction in immunosuppression is the mainstay of PTLD treatment, but it may precipitate graft loss. Retransplantation remains controversial, as immunosuppression resumption may trigger PTLD relapse. Herein, we describe the experience of eight patients who underwent kidney retransplantation after successful PTLD treatment. Epstein-Barr virus (EBV) serology was not known before the first transplantation. PTLD was diagnosed 62.5 months (range 5-323 months) after transplantation and was confined to the renal allograft (n = 1), lymph nodes (n = 2), gastrointestinal tract (n = 4), or central nervous system (n = 1). Immunosuppression tapering (8/8), chemotherapy (6/8), oral cavity lymphoma excision (1/8), and allograft nephrectomy (1/8) led to hematological remission in all patients. Retransplantation was performed at a median of 55.5 months (range 29-95 months) after PTLD diagnosis. After a median follow-up of 62.5 months (range 2-125 months) allograft survival was 87.5% (seven functioning grafts, one failed graft from chronic rejection), with no recurrence of PTLD. In all, five patients remain alive; the other three died from causes other than PTLD. In conclusion, kidney retransplantation appears to be safe in patients with prior PTLD and without major risk of hematological recurrence provided that PTLD has remitted.

The renin-aldosterone axis in kidney transplant recipients and its association with allograft function and structure.

The level of the renin-angiotensin-aldosterone system (RAAS) activity in kidney transplant recipients has not been extensively studied or serially profiled. To describe this axis and to determine its association with glomerular filtration rate (GFR) change, interstitial expansion, and end-stage renal disease (ESRD), we measured plasma renin activity (PRA) and plasma aldosterone levels annually for 5 years in 153 kidney transplant recipients randomly assigned to losartan or placebo. PRA and plasma aldosterone levels were in the normal range at all times and did not vary by immunosuppression regimen. Those on losartan exhibited higher PRA but similar plasma aldosterone levels. Neither baseline nor serial PRA or plasma aldosterone levels were associated with GFR decline, proteinuria, or interstitial expansion. Losartan use (hazard ratio (HR) 0.48 (95% confidence interval (CI) 0.21-1.0), insignificant) and Caucasian donor (HR 0.18 (95% CI 0.07-0.4) significant) were associated with less doubling of serum creatinine, death, or ESRD. Hypertension, <3 human leukocyte antigen matches, the combination of tacrolimus-rapamycin, and acute rejection were associated with more events. Neither PRA nor plasma aldosterone levels were independently associated with this outcome. Higher serial plasma aldosterone levels were associated, however, with a significantly higher risk of ESRD (HR 1.01 (95% CI 1.00-1.02)). Thus, systemic RAAS is not overly activated in kidney transplant recipients, but this may not reflect the intrarenal system. Importantly, plasma aldosterone levels may be associated with more ESRD.

Cystatin C enhances glomerular filtration rate estimating equations in kidney transplant recipients.

BACKGROUND: The glomerular filtration rate (GFR) estimating equation incorporating both cystatin C and creatinine perform better than those using creatinine or cystatin C alone in patients with reduced GFR. Whether this equation performs well in kidney transplant recipients cross-sectionally, and more importantly, over time has not been addressed. METHODS: We analyzed four GFR estimating equations in participants of the Angiotensin II Blockade for Chronic Allograft Nephropathy Trial (NCT 00067990): Chronic Kidney Disease Epidemiology Collaboration equations based on serum cystatin C and creatinine (eGFR (CKD-EPI-Creat+CysC)), cystatin C alone (eGFR (CKD-EPI-CysC)), creatinine alone (eGFR (CKD-EPI-Creat)) and the Modification of Diet in Renal Disease study equation (eGFR (MDRD)). Iothalamate GFR served as a standard (mGFR). RESULTS: mGFR, serum creatinine, and cystatin C shortly after transplant were 56.1 ± 17.0 ml/min/1.73 m(2), 1.2 ± 0.4 mg/dl, and 1.2 ± 0.3 mg/l respectively. eGFR (CKD-EPI-Creat+CysC) was most precise (R(2) = 0.50) but slightly more biased than eGFR (MDRD); 9.0 ± 12.7 versus 6.4 ± 15.8 ml/min/1.73 m(2), respectively. This improved precision was most evident in recipients with mGFR >60 ml/min/1.73 m(2). For relative accuracy, eGFR (MDRD) and eGFR (CKD-EPI-Creat+CysC) had the highest percentage of estimates falling within 30% of mGFR; 75.8 and 68.9%, respectively. Longitudinally, equations incorporating cystatin C most closely paralleled the change in mGFR. CONCLUSION: eGFR (CKD-EPI-Creat+CysC) is more precise and reflects GFR change over time reasonably well. eGFR (MDRD) had superior performance in recipients with mGFR between 30 and 60 ml/min/1.73 m(2).

Low birthweight and risk of albuminuria in living kidney donors.

Low birthweight is linked to hypertension, chronic kidney disease and even end-stage renal disease. We hypothesized that living kidney donors born with lower birthweight may be at increased risk of hypertension, albuminuria, or reduced GFR beyond what is typical following uninephrectomy. Two hundred fifty-seven living kidney donors who donated at the University of Minnesota between 1967 and 2005 underwent iohexol GFR and urinary albumin excretion measurements. Predictors of iohexol GFR <60 mL/min/1.73 m(2), albuminuria, and hypertension were examined using logistic regression. Predictors examined include age at GFR measurement, time since donation, BMI, gender, serum creatinine level (at donation and GFR measurement), systolic and diastolic blood pressure, race, and birthweight. The latter was obtained through self-report and verified through birth certificates and family members. Older age, higher BMI, and time from donation were associated with reduced GFR. Older age and higher BMI were also associated with hypertension. Birthweight was not associated with GFR <60 mL/min/1.73 m(2): OR=0.70, 95% CI (0.28, 1.74), p = 0.45 or hypertension: OR=0.92, 95% CI (0.46, 1.84), p = 0.82 but was associated with albuminuria: OR=0.37, 95% CI (0.15, 0.92), p = 0.03. These data further strengthen the link between low birthweight and potential adverse renal outcomes.

Medical outcomes of adolescent live kidney donors.

Living kidney donation from donors <18 yr of age is uncommon. The majority of donations from adolescents took place several decades ago providing a unique opportunity to study true long-term consequences of donation. We compared survival, renal outcomes, and rates of hypertension and diabetes among 42 adolescent donors and matched older controls. Adolescent donors were matched with donors 18-30 yr on the following: gender, relation to the recipient, BMI at donation, eGFR at donation, and year of donation. After a mean follow-up of 31.8 ± 8.0 yr, 94.9% of adolescent donors were alive vs. 93.8% of controls. There was no significant difference in having eGFR (MDRD) <60 mL/min/1.73 m(2) (26.1% vs. 40.9%), hypertension (35.9% vs. 39.4%), diabetes (5.1% vs. 12.5%), or proteinuria (15.4% vs. 14.1%): adolescent donors vs. controls for all comparisons. These data suggest that adolescent donors are not at a higher risk of shortened survival, hypertension, diabetes, or proteinuria. Nevertheless, they probably should donate only when other options are exhausted as they have to live with a single kidney for decades and longer follow-up is needed.

Peritoneal dialysis immediately after kidney transplantation.

Approximately 10% - 20% of adult kidney transplant recipients and as many as 40% of pediatric recipients receive peritoneal dialysis (PD) before kidney transplantation. An important aspect of perioperative kidney transplant care is management of the PD catheter. Peritoneal dialysis can be performed immediately after transplantation for delayed graft function (DGF), which can occur with as many as 20% of deceased-donor kidney grafts, especially when expanded criteria or organs from donation after cardiac death are used. However, leaving the PD catheter in place has been associated with an increased risk for infections such as peritonitis and exit-site infection, even when the catheter is not used. Although no consensus has been reached about the management of PD catheters after kidney transplantation, transplant centers should have a low threshold for PD catheter removal at the time of surgery, especially in recipients with a low risk for DGF. In individuals with high risk for DGF the PD catheter can be left in place, but it must be removed in a timely manner once it is no longer needed.

Calcineurin inhibitor nephrotoxicity: a review and perspective of the evidence.

BACKGROUND: There is no doubt that acute calcineurin inhibitor (CNI) nephrotoxicity exists; however, chronic CNI nephrotoxicity is questionable at best. METHODS: We reviewed the literature to identify original articles related to the use of CNIs in renal and nonrenal solid organ transplantation in order to examine the available evidence about their chronic nephrotoxicity and contribution to graft failure. RESULTS: Early clinical experience and animal studies support the evidence of CNI nephrotoxicity. These findings evolved into the dogma that CNI nephrotoxicity is the major cause of late renal allograft failure. However, in transplanted kidneys the specific role of chronic CNI nephrotoxicity has been questioned. The emerging literature clearly highlights the lack of solid evidence for the role of CNIs as the sole and major injurious agents that cause chronic renal dysfunction and subsequent graft failure. Most of the evidence available to date is against complete CNI avoidance, and minimization appears to be a more viable strategy. It is becoming increasingly clear that the typical pathological lesions linked to chronic CNI use are highly nonspecific, and most of the chronic changes that have been attributed to chronic CNI nephrotoxicity are the consequences of previously unrecognized immunologic injuries. One needs to keep in mind that the potential risk of side effects of CNI use should be balanced against the risk of rejection. CONCLUSIONS: More research should focus on addressing the true causes of chronic graft dysfunction rather than focusing on the overexaggerated contribution of CNIs to late graft loss.

Renal involvement in systemic sclerosis.

Systemic sclerosis is a rare autoimmune vasculopathy associated with dysregulated innate and adaptive immunity that leads to generalized systemic fibrosis. Renal involvement occurs in a significant proportion of systemic sclerosis patients, and is associated with worse outcome. Scleroderma renal crisis (SRC) is the most studied and feared renal complication described in systemic sclerosis. However, with the emergence of ACE inhibitors and better management, the mortality rate of SRC has significantly decreased. Renal disease in systemic sclerosis offers a wide array of differential diagnoses that may be challenging for the clinician. The spectrum of renal manifestations in systemic sclerosis ranges from an isolated decrease in glomerular filtration rate, increased intrarenal arterial stiffness, and isolated proteinuria due to SRC to more rare manifestations such as association with antiphospholipid antibody nephropathy and ANCA-associated vasculitis. The changes observed in the kidneys in systemic sclerosis are thought to be due to a complex interplay of various factors, including renal vasculopathy, as well as the involvement of the complement system, vasoactive mediators such as endothelin-1, autoimmunity, prothrombotic and profibrotic cytokines, among others. This literature review aims to provide an overview of the main renal manifestations in systemic sclerosis by discussing the most recent epidemiological and pathophysiological data available and the challenges for clinicians in making a diagnosis of renal disease in patients with systemic sclerosis.

Bone health in autosomal dominant polycystic kidney disease (ADPKD) patients after kidney transplantation.

ADPKD is caused by pathogenic variants in PKD1 or PKD2, encoding polycystin-1 and -2 proteins. Polycystins are expressed in osteoblasts and chondrocytes in animal models, and loss of function is associated with low bone mineral density (BMD) and volume. However, it is unclear whether these variants impact bone strength in ADPKD patients. Here, we examined BMD in ADPKD after kidney transplantation (KTx). This retrospective observational study retrieved data from adult patients who received a KTx over the past 15 years. Patients with available dual-energy X-ray absorptiometry (DXA) of the hip and/or lumbar spine (LS) post-transplant were included. ADPKD patients (n = 340) were matched 1:1 by age (±2 years) at KTx and sex with non-diabetic non-ADPKD patients (n = 340). Patients with ADPKD had slightly higher BMD and T-scores at the right total hip (TH) as compared to non-ADPKD patients [BMD: 0.951 vs. 0.897, p < 0.001; T-score: -0.62 vs. -0.99, p < 0.001] and at left TH [BMD: 0.960 vs. 0.893, p < 0.001; T-score: -0.60 vs. -1.08, p < 0.001], respectively. Similar results were found at the right femoral neck (FN) between ADPKD and non-ADPKD [BMD: 0.887 vs. 0.848, p = 0.001; T-score: -1.20 vs. -1.41, p = 0.01] and at left FN [BMD: 0.885 vs. 0.840, p < 0.001; T-score: -1.16 vs. -1.46, p = 0.001]. At the LS level, ADPKD had a similar BMD and lower T-score compared to non-ADPKD [BMD: 1.120 vs. 1.126, p = 0.93; T-score: -0.66 vs. -0.23, p = 0.008]. After adjusting for preemptive KTx, ADPKD patients continued to have higher BMD T-scores in TH and FN. Our findings indicate that BMD by DXA is higher in patients with ADPKD compared to non-ADPKD patients after transplantation in sites where cortical but not trabecular bone is predominant. The clinical benefit of the preserved cortical bone BMD in patients with ADPKD needs to be explored in future studies.

Should peritoneal dialysis be the preferred therapy pre-kidney transplantation?

The impact of pre-transplant dialysis modality on kidney transplant outcomes has been the impetus for many discrepant reports. Although candidacy for kidney transplantation may not necessarily be the main factor in deciding the choice of pre-transplant dialysis modality, certain complications are thought to be associated with one dialysis modality compared with the other and should be acknowledged. Most of the evidence to date, especially that for lower rates of delayed graft function, indicates an advantage for peritoneal dialysis (PD) over hemodialysis. More importantly, some groups of recipients clearly benefit more from receiving PD pre-transplant, a finding that was recently reported for high-risk adult recipients of expanded-criteria donor organs and pediatric recipients of living-donor organs. On the other hand, PD may be associated with a higher risk of early graft thrombosis. Moreover, the published literature highlights the need for caution in older candidates with a family history of diabetes mellitus because of potential higher risk for new-onset post-transplantation diabetes mellitus in PD patients. Interestingly, prospective studies validating those findings are scarce; most of the published reports have been limited by either small patient numbers or a lack of consideration of other confounding risk factors. In the present review, we examined the available literature related to the influence of pre-transplant dialysis modality on post-transplant allograft and recipient outcomes.

Kidney Transplant Outcomes of Patients With Multiple Myeloma.

Introduction: Data on kidney transplantation (KTx) outcomes of patients with multiple myeloma (MM) are very limited. Methods: We investigated the outcomes of patients with MM who underwent KTx between 1994 and 2019. Results: A total of 12 transplants from 11 patients were included. At the time of KTx, 6 were classified as having stringent complete response (CR), 2 as CR, 2 as very good partial response (VGPR), and 2 as partial response (PR). With a median follow-up of 40 (minimum-maximum, 5-92) months after KTx, hematologic progression occurred in 9 transplants (75%). There were 3 grafts (25%) that failed, and 5 patients (45.5%) experienced death with functioning allografts. Graft survival at 1 and 5 years was 82.5% and 66%, respectively. Progression-free survival (PFS) rates of the cohort at 1, 3, and 5 years were 83.3%, 55.6%, and 44.4%, respectively. The estimated median PFS of patients who received bortezomib at any time (pre-KTx and/or post-KTx) was not reached, whereas it was 24 months for those who never received bortezomib (P = 0.281). Overall survival (OS) rates of the cohort at 1, 3, and 5 years were 81.8%, 61.4%, and 61.4%, respectively. OS of patients who received bortezomib at any time was 87.5%, 72.9%, and 72.9%, and that for those who never received bortezomib was 66.7%, 33.3%, and 33.3% (P = 0.136). All deaths occurred owing to hematologic progression or treatment-related complications. Conclusion: Kidney transplant outcomes of patients with myeloma who received bortezomib before or after KTx seem to be more favorable. Nevertheless, relapse after KTx in MM is still common. More studies are needed to better determine who benefits from a KTx.

Clinical and Kidney Structural Characteristics of Living Kidney Donors With Nephrolithiasis and Their Long-term Outcomes.

BACKGROUND: Nephrolithiasis in living kidney donors is concerning due to the potential impact on long-term postdonation kidney function. METHODS: We performed a cohort study of living kidney donors from 2 centers with a baseline computed tomography scan and implantation renal biopsy. Donors (>5 y since donation) completed a follow-up survey or underwent chart review to assess eGFR and incident hypertension. Stone formers were classified as symptomatic if they had a past symptomatic episode or asymptomatic if only incidental radiographic kidney stones were identified during donor evaluation. We compared baseline clinical, imaging, and biopsy characteristics by stone former status including review of metabolic evaluations in stone formers. Long-term risks of renal complications (low eGFR and hypertension) by stone former status were evaluated. RESULTS: There were 12 symptomatic and 76 asymptomatic stone formers among 866 donors. Overall, baseline clinical characteristics and implantation biopsy findings were similar between stone formers and non-stone formers. After a median follow-up of 10 y, stone former status was not associated with eGFR <60 mL/min/1.73 m2, eGFR <45 mL/min/1.73 m2, or hypertension. CONCLUSIONS: Both asymptomatic and symptomatic SF have favorable histology findings at baseline. Long-term kidney outcomes were favorable in select stone formers with no evident increased long-term risk for decreased kidney function or hypertension after donation.

Guiding Kidney Transplantation Candidates for Effective Weight Loss: A Clinical Cohort Study.

Background: Obesity is increasingly common in kidney transplant candidates and may limit access to transplantation. Obesity and diabetes are associated with a high risk for post-transplant complications. The best approach to weight loss to facilitate active transplant listing is unknown, but bariatric surgery is rarely considered due to patient- and physician-related apprehension, among other factors. Methods: We aimed to determine the magnitude of weight loss, listing, and transplant rates in 28 candidates with a mean BMI of 44.4±4.6 kg/m2 and diabetes treated conservatively for 1 year post weight-loss consultations (group 1). Additionally, we evaluated 15 patients (group 2) who met the inclusion criteria but received bariatric intervention within the same time frame. All patients completed a multidisciplinary weight management consultation with at least 1 year of follow-up. Results: In the conservatively managed group (group 1), the mean weight at the time of initial consultation was 126.5±18.5 kg, and the mean BMI was 44.4±4.6 kg/m2. At 1 year post weight-loss consultation, the mean weight decreased by 4.4±8.2 kg to 122.9±17 kg, and the mean BMI was 43±4.8 kg/m2, with a total mean body weight decrease of 3% (P=0.01). Eighteen patients (64%) did not progress to become candidates for active listing/transplantation during the follow-up time of 4±2.9 years, with 15 (54%) subsequently developing renal failure/diabetes-related comorbidities prohibitive for transplantation. In contrast, mean total body weight decreased by 19% at 6 months post bariatric surgery, and the mean BMI was 34.2±4 and 32.5±3.7 kg/m2 at 6 and 12 months, respectively. Bariatric surgery was strongly associated with subsequent kidney transplantation (HR=8.39 [95% CI 1.71 to 41.19]; P=0.009). Conclusions: A conservative weight-loss approach involving multidisciplinary consultation was ineffective in most kidney transplant candidates with diabetes, suggesting that a more proactive approach is needed.