COVID-19 pneumonia in kidney transplant recipients: Focus on immunosuppression management.

BACKGROUND: The coronavirus disease of 2019, also known as COVID-19, has been declared a global pandemic. Significant controversies exist regarding treatment modalities for this novel disease, especially in immunocompromised patients. Experience with management of COVID-19 in kidney transplant recipients is scarce; effects of this virus on immunosuppressed individuals are not well understood. METHODS: We identified 30 renal transplant recipients with confirmed COVID-19 pneumonia who were admitted to inpatient between March 2020 and April 2020. All patients received a 5-day course of hydroxychloroquine and azithromycin; half of the patients received methylprednisolone. During hospitalization, calcineurin inhibitors and antimetabolites were held; prednisone was continued. RESULTS: Clinical presentation of flu-like symptoms was similar to those in the general population. Hyponatremia, lymphopenia, acute kidney injury, and elevated inflammatory markers were common. Over the course of follow-up, 23 have been discharged home with a functioning allograft and in stable condition; 4 experienced acute kidney injury requiring renal replacement therapy; 7 patients were intubated, and 6 expired. The mortality rate in our cohort was 20%. CONCLUSION: Our findings described the characteristics and outcomes of this highly fatal illness in a multi-ethnic kidney transplant cohort, with insights on immunosuppression management that could further our understanding of this unique disease in immunocompromised populations.

Mortality after Renal Allograft Failure and Return to Dialysis.

INTRODUCTION: The outcomes of patients who fail their kidney transplant and return to dialysis (RTD) has not been investigated in a nationally representative sample. We hypothesized that variations in management of transplant chronic kidney disease stage 5 leading to kidney allograft failure (KAF) and RTD, such as access, nutrition, timing of dialysis, and anemia management predict long-term survival. METHODS: We used an incident cohort of patients from the United States Renal Data System who initiated hemodialysis between January 1, 2003 and December 31, 2008, after KAF. We used Cox regression analysis for statistical associations, with mortality as the primary outcome. RESULTS: We identified 5,077 RTD patients and followed them for a mean of 30.9 ± 22.6 months. Adjusting for all possible confounders at the time of RTD, the adjusted hazards ratio (AHR) for death was increased with lack of arteriovenous fistula at initiation of dialysis (AHR 1.22, 95% CI 1.02-1.46, p = 0.03), albumin <3.5 g/dL (AHR 1.33, 95% CI 1.18-1.49, p = 0.0001), and being underweight (AHR 1.30, 95% CI 1.07-1.58, p = 0.006). Hemoglobin <10 g/dL (AHR 0.96, 95% CI 0.86-1.06, p = 0.46), type of insurance, and zip code-based median household income were not associated with higher mortality. Glomerular filtration rate <10 mL/min/1.73 m2 at time of dialysis initiation (AHR 0.83, 95% CI 0.75-0.93, p = 0.001) was associated with reduction in mortality. CONCLUSIONS: Excess mortality risk observed in patients starting dialysis after KAF is multifactorial, including nutritional issues and vascular access. Adequate preparation of patients with failing kidney transplants prior to resuming dialysis may improve outcomes.

Determination of unacceptable antigens by summation of anti-HLA eplet antibody strength (MFI) based on single antigen bead assays: Excellent correlation with negative cell based cross matches.

The reliability of single antigen bead (SAB) assays and their use in predicting a negative cell based cross match (CBXM) is essential in the era of expanded organ sharing. A wide range of accuracy (80-95%) in predicting negative CBXM has been reported. We hypothesized that in SAB assays an antibody against an HLA eplet that was common among a number of different HLA alleles would be distributed among all of the shared eplet positive SABs. This would reduce binding to the donor specific SAB resulting in an under-estimate of antibody strength. We tested this proposal in adsorption studies using, instead of lymphocytes, a novel reagent, single-SAB (sSAB). Properties of SAB assays were examined that provided a basis for conducting adsorption - elution experiments with the sSABs. We found that incubation of sera with sA*02:01 or sB*42:01 not only depleted reactivity to these alleles but also depleted reactivity to beads that shared the reactive eplet. Anti-eplet strength from SAB data (sum of the MFI of eplet positive SABs (MFI-s) was compared with CBXM out comes in two case studies and with 99 proficiency testing sera. In these validation studies, an MFI-s above 11,000 was associated with a positive FCXM. This approach was placed into clinical practice for listing unacceptable antigens that shared a common eplet. CDCXMs (n = 3261) and FCXMs (n = 1012) were performed on patients listed in UNOS for deceased donor kidneys. All CDCXMs were negative and all FCXMs except one were negative. We conclude that summation of eplet strength provides a highly reliable method of predicting prospective negative CBXMs resulting in substantial savings of time and effort. Based on shared eplet summation data, CMS/NYSDOH has accepted our bead based XM (BBXM) method (aka, virtual XM) performed prior to transplant as fulfilling the regulation that XM results be available before kidney transplantation.

Long-term kidney transplant outcome in obese patients in a predominantly African American population.

The impact of obesity on long-term kidney transplant outcome has largely been studied in non-African American patients. This study seeks to determine differences in outcome between obese and non-obese patients after kidney transplantation, in a predominantly African American population. We reviewed 642 adult renal transplant recipients who received their transplants at SUNY Downstate Medical Center between 1998 and 2007. Sixty-six percent of the patients studied were African American. The patients were divided into five groups according to their BMI status: underweight <20, normal 20-24.9, overweight 25-29.9, obese 30-34.9, and morbidly obese ≥35. There were no differences in race, gender, cytomegalovirus infection, type of transplant, panel-reactive antibody, retransplant status, flow cytometry cross-match results, mycophenolate mofetil therapy, and total HLA mismatch status. The mean discharge serum creatinine in the morbidly obese group was significantly higher than in other groups (p < 0.001). The difference in creatinine level disappeared at six wk and six months (p > 0.5), respectively. Acute rejection rates, delayed graft function, graft survival, and patient survival were not different between the groups. The findings from this large single-center study suggest that obese and morbidly obese patients had similar outcomes compared to other weight groups. Obese and morbidly obese African American patients should not be excluded from kidney transplantation on the basis of weight alone.

Association of Physical Function and Survival in Older-Adult Renal Transplant Recipients.

There is an increase in older-adult renal transplant recipients in United States. The objective of this study was to assess the association between physical function (PF) and patient survival in renal transplant recipients who are aged 65 years or older. Using United Network for Organ Sharing (UNOS) data from 2007 to 2016, renal transplant recipients aged 65 years or older were included. Multivariable Cox regression was used to assess associations between survival and functional status adjusted for age, sex, race, donor quality, diabetes, and dialysis vintage. The study identified 26,721 patients. Patient survival was significantly higher in recipients who needed no assistance and lowest in patients in need of total assistance (P < .0001). In deceased donor (DD) transplants, the relative risk for mortality was 2.06 (1.74-2.43) for total assistance and 1.17 (1.08-1.28) for moderate assistance compared to no assistance (P < .0001). In living donor (LD) transplants, the relative risk of mortality was 1.38 (0.78-2.42) for patients needing total assistance and 1.37 (1.14-1.65) for patients needing moderate assistance compared to patients who did not need assistance (0.003). PF is an independent predictor of post-transplant mortality. Assessment of older potential renal transplant recipients should include assessment and standardization of functional status to counsel about post-transplant survival.

Long-term outcomes of dual kidney transplantation-a single center experience.

The shortage of kidney donors has led to broadening of the acceptance criteria for deceased donor organs beyond the traditional use of young donors. We determined long-term post-transplant outcomes in recipients of dual expanded criteria donor kidneys (dECD, n = 44) and compared them to recipients of standard criteria donor kidneys (SCD, n = 194) and single expanded criteria donor kidneys (sECD, n = 62). We retrospectively reviewed these 300 deceased donor kidney transplants without primary non-function (PNF) or death in the first two wk, at our center from 1996 to 2003. The three groups were similar in baseline characteristics. Kidney allograft survival and patient survival (nine yr) were similar in the three respective donor groups, SCD, sECD and dECD (60% vs. 59% vs. 64% and 82% vs. 73% vs. 73%). Acute rejection in the first three months was 23.2%, 16.1%, and 22.7% in SCD, sECD and dECD, respectively (p = 0.49) and delayed graft function was 25.2%, 31.9% and 17.1% in the three groups, respectively (p = 0.28). When PNF and death within the first two wk was included, there was no significant difference in graft survival between the three groups. In our population, recipients of dECD transplants have acceptable patient and graft survival with kidneys that would have usually been discarded.

Effect of Age on Leukopenia Following Renal Transplantation at a Single Center.

INTRODUCTION: Leukopenia in renal transplant recipients occurs commonly within the first year following transplantation; however, literature on the effects of age on leukopenia is scarce. DESIGN: A single-center, retrospective review was conducted on 141 recipients transplanted from January 2011 to December 2015. Transplant recipients were characterized by age <60 years (n = 94) or age 60 years and older (n = 47) for analysis. RESULTS: A greater incidence of leukopenia was seen in the older cohort compared to the younger cohort (64% vs 55%). Of those patients who developed leukopenia, the older cohort (n = 30) had a higher incidence of hospitalization for leukopenia (30% vs 23%) but a lower incidence of hospitalization for infection (20% vs 25%) compared to the younger cohort (n = 52). Additionally, one month following mycophenolate mofetil (MMF) discontinuation, the older cohort had reduced recovery of their white blood cell count (+263.8% vs +272.5%) and experienced less recurrent leukopenic episodes (50% vs 67%) and rejection episodes (0% vs 22%) compared to the younger cohort, alluding to the need for less immunosuppression. CONCLUSIONS: Age at transplantation was not associated with the development of leukopenia; however, older patients had a higher incidence of leukopenia and hospitalization for leukopenia. Dose reduction or discontinuation of MMF should be considered in older kidney transplant recipients who develop leukopenia.

Effect of peripheral vascular disease on kidney allograft outcomes: a study of U.S. Renal data system.

BACKGROUND: The U.S. Renal Data System was used to analyze renal allograft outcomes in patients with peripheral vascular disease (PVD) at the time of transplant listing. METHODS: We used an incident cohort of patients who underwent renal transplantation between June 2004 and September 2009. We defined PVD as symptomatic PVD at wait-listing. Comorbid conditions were diabetes mellitus, ischemic heart disease, cerebrovascular disease, hypertension, and smoking. Chi-square test, Student's t test, and Cox regression were used for statistical associations. RESULTS: The mean graft survival was 55.3±0.40 months in patients with PVD versus 60.8±0.06 months in patients without PVD. There was an increased risk of graft failure with PVD (hazard ratio, 2.01; 95% confidence interval, 1.83-2.21; P=0.0001). After adjusting for other variables, PVD remained an independent risk factor for graft failure. Patients with PVD had lower death-censored graft survival versus patients without PVD at 1 year (93.3% vs. 96.6%), 2 years (89.7% vs. 95%), and 3 years (87.2% vs. 93.7%). All-cause mortality was higher in PVD versus without PVD (6.2% vs. 3.0%). In African Americans, the mean allograft survival was 54.8±0.98, months with PVD versus 59.7±0.135 months without PVD (P=0.0001). In non-African Americans, the mean allograft survival was 55.4±0.44 months with PVD versus 61.1±0.069 months without PVD (P=0.0001). There were no differences in survival between African Americans with PVD and non-African Americans with PVD. CONCLUSIONS: Patients with PVD have inferior allograft and patient survival versus those without PVD. Caution should be exercised when placing patients with symptomatic PVD or amputation on the wait-list.

Impact of renal posttransplantation amputation on allograft outcomes: a study of United States renal data system.

BACKGROUND: The prevalence of renal posttransplantation amputation and its impact on allograft and patient survival have not been widely reported. METHODS: We used an incident cohort of patients who underwent renal transplantation between June 2004 and September 2009. Amputation data were obtained using Medicare institutional claim forms. Baseline demographics and comorbidities, such as peripheral vascular disease (PVD), diabetes, ischemic heart disease, cerebrovascular disease, hypertension, and smoking, were captured. The chi-square and t tests were used for statistical associations. Kaplan-Meier survival curves were plotted for renal allograft and patient survival. Independent associations between patient factors and amputation were examined using multivariable Cox regression analysis. RESULTS: Of the 85,873 renal transplant recipients, 1062 patients had amputation. The prevalence of amputation was higher in those with PVD versus those without PVD at listing (5.6% vs. 1%; P=0.0001). Mean allograft survival was 55.5±0.55 months in patients with amputation versus 60.6±0.06 months in patients without amputation (P=0.0001). All-cause mortality was higher in patients with amputation versus those without amputation (19.9% vs. 7.3%; P=0.0001). Mean allograft survival was 60.97±0.67 months in non-African Americans without amputation versus 55.7±0.65 months in non-African Americans with amputation. Allograft survival was 59.73±0.13 months in African Americans without amputation versus 54.9±1.06 months in African Americans with amputation. In patients with amputation, race did not have any impact. Infectious complications were noted in 39 patients leading to death. CONCLUSIONS: Amputation is associated with decreased allograft and patient survival. Early detection and preventive strategies for PVD may decrease amputation rate and improve survival.

Poor kidney allograft survival associated with positive B cell - Only flow cytometry cross matches: a ten year single center study.

The presence of donor specific antibody (DSA) to class 1 or class 2 HLA as detected respectively in T cell or B cell - only flow cytometry cross matches (FCXMs) are risk factors for renal allograft survival, though the comparative risk of these XMs has not been definitively established. Allograft survival and FCXM data in 624 microcytotoxicity (CDC) XM negative kidney transplants were evaluated. Short and long term allograft survival was significantly less in recipients with T(-) B(+) FCXMs (1 year, 74%, 10 year, 58%) compared to T(+) B(+) FCXMs (1 year, 84%, 10 year, 68%) and to T(-) B(-) FCXM (1 year, 90%, 10 year, 85%). Risk factors were positive FCXM, deceased donor (DD) transplantation and donor age, but not race, gender, recipient age or previous transplant. Recipients with T(-) B(+) and T(+) B(+) FCXMs were at 4.5 and 2.5 fold greater risk, respectively, of DD allograft failure compared to patients with T(-) B(-) FCXMs. The quantitative value of FCXM did not correlate with the duration of graft survival. We conclude that patients with DSA to class 2 HLA have a greater risk of early and late allograft failure compared to patients with DSA to class 1 HLA.