Ryan, Margaret

Introduction. Increased steatosis on preimplant liver frozen section is associated with delayed graft function and primary nonfunction. Efforts to standardize histologic assessment have proven difficult. Frozen section artifact and lipopeliosis complicate the detection of steatosis. We aimed to develop and validate an AI model to recognize large droplet fat and fat induced artifact (FIA)/lipopeliosis on preimplantation frozen section and to correlate the AI results with post-transplant clinical parameters. Methods. The model was applied to 161 consecutive liver transplant specimens with preimplant slides. Results were correlated with traditional and Banff histologic assessment and clinical parameters. Results. By traditional assessment, steatosis ranged from 0%–40%. The AI model identified a range of 0 to 15.9% steatosis. There was no difference in patient survival by any measures of steatosis. AI steatosis correlated with increased risk of early allograft dysfunction (OR = 1.63, P < .001), respiratory failure (OR = 1.21, P = .003), and more advanced fibrosis (OR = 1.18, P = .030), but was not correlated with graft or patient survival. FIA/lipopeliosis were identified in a range of 0 to 6.42%. In univariate analysis the percentage of FIA/lipopeliosis correlated with both graft and patient survival ( P = .044 and P = .009, respectively), but was not associated with increased risk of early allograft dysfunction, respiratory failure, or advanced fibrosis. Conclusions. We developed an AI model that quantitates large droplet fat and FIA/lipopeliosis on frozen section slides and found a correlation with post-transplant outcomes. Further studies on larger, multi-institutional cohorts with higher fat containing donors are necessary to determine the role this model may have in organ acceptance decisions.

ABSTRACTBackgroundAlternate complement dysregulation postrenal transplantation can result in thrombotic microangiopathy (TMA). There is a scarcity of data regarding outcomes based on the timing of TMA post‐transplant, coupled with a lack of follow‐up biopsy findings post TMA diagnosis. This study aims to assess allograft and patient outcomes in individuals developing early TMA, defined within 4 months post‐transplantation, and explore any differences in follow‐up surveillance biopsies compared to a non‐TMA group.DesignThis is a single center retrospective study between January 1, 2002 and October 10, 2019. Patients who developed TMA within 4 months post‐transplantation were compared to a propensity matched non‐TMA group.ResultsThirty‐one patients developed TMA within 4 months of renal transplantation. Index TMA biopsy featured noticeable glomerular, and vascular lesions along with acute tubular injury. Four‐month surveillance biopsy showed significant glomerulitis, transplant glomerulopathy and chronic interstitial fibrosis as compared to non‐TMA group. However, at 1 year, these differences were no longer significant. There was no significant difference in patient survival (TMA vs. non‐TMA,p = 0.083); however, death censored graft survival was significantly lower in the TMA group (p < 0.001). TMA patients had a significantly lower estimated glomerular filtration rate at 4 months and at 1 year as compared to the non‐TMA group.ConclusionEarly onset TMA post renal transplant leads to decreased renal function and lower graft survival. Early recognition and prompt treatment may help in reducing the adverse outcomes.

ABSTRACT Histiocytic sarcoma (HS) is a rare hematologic malignancy that has historically been treated with lymphoma-based regimens with a median survival of 6 months. We describe a case of a 51-year-old woman who presented with acute back pain and cord compression. She was diagnosed with HS with diffuse skeletal lesions and high expression of programmed death ligand 1 (PD-L1). She was subsequently treated with chemotherapy plus off-label use of pembrolizumab followed by allogeneic stem cell transplantation. Ultimately, the patient died in the setting of progression of disease 17 months after her stem cell transplantation and 26 months after her diagnosis. This article also presents a literature review of cases of HS treated with programmed death ligand inhibition.

(1) Background: Acute kidney injury (AKI) kidneys have high non-utilization rates due to concerns regarding unfavorable outcomes. In this paper, we aimed to review the past, present, and future opinions on AKI kidneys. (2) Methods: A PubMed search was conducted for topics relevant to AKI kidney transplantation. (3) Results: Current short- and long-term data on AKI kidneys have demonstrated good outcomes including favorable graft function and survival. The role of procurement biopsies is controversial, but they have been shown to be beneficial in AKI kidneys by allowing clinicians to differentiate between reversible tubular injury and irreversible cortical necrosis. Machine perfusion has also been applied to AKI kidneys and has been shown to reduce delayed graft function (DGF). The incidence of DGF increases with AKI severity and its management can be challenging. Strategies employed to counteract this have included early initiation of dialysis after kidney transplantation, early targeting of adequate immunosuppression levels to minimize rejection risk, and establishment of outpatient dialysis. (4) Conclusions: Despite good outcomes, there continue to be barriers that impact AKI kidney utilization. Successful strategies have included use of procurement biopsies or machine perfusion and expectant management of DGF. With increasing experience, better use of AKI kidneys can result in additional opportunities to expand the donor pool.

Background. The Banff classification scheme provides a framework for interpreting transplant kidney biopsies and has undergone various updates in the past 2 decades especially related to antibody-mediated rejection. The clinical significance of early glomerulitis seen within 4 mo on protocol biopsies has received limited attention. We hypothesized that early glomerulitis seen on protocol biopsies will lead to significant adverse outcomes as assessed by histopathology and allograft outcome. Methods. A single-center retrospective study of a cohort of patients who underwent protocol biopsies within 4 mo after transplantation with timely follow-up protocol biopsies were assessed. Patients with recurrent glomerulonephritis were excluded. Results. We calculated glomerulitis (g) scores for 2212 biopsy specimens and identified 186 patients with glomerulitis (g > 0) and 2026 patients without glomerulitis (g = 0). The progression to chronic transplant glomerulopathy at 1 and 2 y was higher in patients with g > 0 as compared with g = 0 (year 1, 10.7% versus 2.3% [P < 0.001]‚ respectively; year 2, 17.2% versus 4.3% [P < 0.001], respectively) with no difference in other chronic lesions. The death-censored graft failure rate was higher in patients with g > 0 as compared with g = 0 (hazard ratio, 1.68 [95% CI, 1.07-2.65]; P = 0.02). We did not find any difference in outcomes in glomerulitis group based on donor-specific antibody. Conclusion. Our findings suggest that early glomerulitis (seen within 4 mo after transplantation) may lead to clinically significant long-term changes and thus could be a target for early intervention therapies.

AbstractHistologic findings on 1‐year biopsies such as inflammation with fibrosis and transplant glomerulopathy predict renal allograft loss by 5 years. However, almost half of the patients with graft loss have a 1‐year biopsy that is either normal or has only interstitial fibrosis. The goal of this study was to determine if there was a gene expression profile in these relatively normal 1‐year biopsies that predicted subsequent decline in renal function. Using transcriptome microarrays we measured intragraft mRNA levels in a retrospective Discovery cohort (170 patients with a normal/minimal fibrosis 1‐year biopsy, 54 with progressive decline in function/graft loss and 116 with stable function) and developed a nested 10‐fold cross‐validated gene classifier that predicted progressive decline in renal function (positive predictive value = 38 ± 34%%; negative predictive value = 73 ± 30%, c‐statistic = .59). In a prospective, multicenter Validation cohort (270 patients with Normal/Interstitial Fibrosis [IF]), the classifier had a 20% positive predictive value, 85% negative predictive value and .58 c‐statistic. Importantly, the majority of patients with graft loss in the prospective study had 1‐year biopsies scored as Normal or IF. We conclude predicting graft loss in many renal allograft recipients (i.e., those with a relatively normal 1‐year biopsy and eGFR > 40) remains difficult.

AbstractBackground and objectivesWe aimed to determine outcomes with transplanting kidneys from deceased donors with severe acute kidney injury requiring acute renal replacement therapy (RRT).Materials and methodsA total of 172 recipients received a kidney from donors with acute kidney injury stage 3 (AKIN3) requiring RRT. We compared the study group to 528 recipients who received a kidney from donors with AKIN stage 3 not on RRT and 463 recipients who received < 85% Kidney Donor Profile Index (KDPI) AKIN stage 0 kidney.ResultsThe study group donors were younger compared to the 2 control groups. Despite higher DGF in the study group, the length of hospital stay and acute rejection were similar. Death censored graft survival (96% AKIN3‐RRT vs. 97%AKIN3 no RRT vs. 96% KDPI < 85% AKIN0,P = 0.26) and patient survival with functioning graft at 1 year (95% across all groups,P = 0.402) were similar. The estimated glomerular filtration rate were similar across the 3 groups after first month. Interstitial fibrosis and tubular atrophy score ≥ 2 on protocol biopsy at time 0, 4 and 12 months were similar. Primary nonfunction was rare and associated with high KDPI.ConclusionsTransplanting selected kidneys from deceased donors with AKIN3 requiring RRT is safe and has good outcomes.

AbstractKidney transplant (KT) outcomes from high kidney donor profile index (KDPI ≥85%) donors with acute kidney injury (AKI) remain underreported. KT from 172 high KDPI Acute Kidney Injury Network (AKIN) stage 0‐1 donors and 76 high KDPI AKIN stage 2‐3 donors from a single center were retrospectively assessed. The AKIN 2‐3 cohort had more delayed graft function (71% vs. 37%, p < .001). At one year, there were no differences in the estimated glomerular filtration rate (44 ± 17 vs. 46 ± 18, p = .42) or fibrosis on protocol biopsy (ci, p = .85). Donor terminal creatinine (p = .59) and length of delayed graft function (p = .39) did not impact one‐year eGFR. There were more primary nonfunction (PNF) events in the high KDPI AKIN 2‐3 group (5.3% vs. 0.6%, p = .02). With a median follow‐up of 3.8 years, one‐year death‐censored graft failure was 3.5% for AKIN 0‐1 and 14.5% for AKIN 2‐3 (HR 2.40, 95% CI 1.24‐4.63, p = .01). Although AKIN stage 2‐3 high KDPI kidneys had comparable one‐year eGFR to AKIN stage 0‐1 high KDPI kidneys, there were more PNF occurrences and one‐year death‐censored graft survival was reduced. Given these findings, additional precautions should be undertaken when assessing and utilizing kidneys from severe AKI high KDPI donors.