Improving frozen section evaluation of procurement donor kidney biopsies and reducing the discard rate: a promising role for artificial intelligence.

There is a worldwide shortage of deceased-donor kidneys available for transplantation, with too many patients dying while on waiting lists for organs. Meanwhile, and particularly in the United States, many recovered kidneys are discarded, often based on results of frozen section evaluation of a screening biopsy read by an on-call pathologist with limited renal pathology experience. A study in this month's issue of Kidney International uses an artificial intelligence-based approach to evaluate these biopsies, which not only improved correlation between biopsy findings and short-to-intermediate term graft survival, but also demonstrated the potential to reduce biopsy-associated organ discard rates by 25% to 30%.

Triaging donor lungs based on a microaspiration signature that predicts adverse recipient outcome.

BACKGROUND: Aspiration is a relative contraindication to accepting donor lungs for transplant and is currently assessed by visual inspection of the airways via bronchoscopy. However, this method is limited as it does not assess for microaspiration. Bile acids measured in large airway bronchial wash (LABW) samples have been shown to be a marker of aspiration in lung transplant recipients. Herein, we investigate the utility of measuring total bile acids (TBA) in donor LABW to predict performance of donor lungs and recipient outcomes. METHODS: TBA was measured in 605 consecutive lung donors at the Toronto Lung Transplant Program. TBA levels were compared in donor lungs deemed unsuitable for transplant, requiring further assessment on ex vivo lung perfusion (EVLP), and those suitable for direct transplantation using Mann-Whitney-U tests. Relationships between LABW TBA concentrations and recipient outcomes were evaluated using multivariable Cox-PH models and log-rank analysis. RESULTS: Donor TBA was highest in lungs deemed unsuitable for transplant and correlated with clinical assessment of aspiration. LABW TBA concentration correlated with calcium, decreased pH, and increased pro-inflammatory mediators in EVLP perfusate. TBA cut-off of 1245 nM was able to differentiate donor lungs directly declined from those suitable for direct transplantation with a 91% specificity (AUROC: 73%). High donor TBA status was associated with the increased rate of primary graft dysfunction, longer time to extubation, and shorter time to chronic lung allograft dysfunction. CONCLUSIONS: In a large retrospective cohort, we observed that donor LABW TBA was associated with suitability of donor lungs for transplant, performance of the organ on EVLP, and adverse recipient outcomes.

Communicating the move to individualized donor selection policy: Framing messages focused on recipients and safety.

BACKGROUND: Men-who-have-sex-with-men (MSM) have been deferred from donating blood. However, recent evidence supports the adoption of donor screening based on individuals' sexual behavior over population-based criteria. We explore how best to frame communications about adopting this change to minimize any potential negative consequences (e.g., reduced donor numbers). We examine the effectiveness of risk (emphasizing safety vs. emphasizing low risk), and focus (donor vs. recipient) frames on intentions to donate blood (approach) or feeling deterred from donating (avoid), and mechanisms linked to under-reporting sexual behavior. STUDY DESIGN AND METHODS: We conducted a 2 (risk frame: risk vs. safety) by 3 (focus: donor vs. recipient vs. both) between-subjects online experiment (n = 2677). The main outcomes were intentions to donate and feelings of being put-off/deterred from donating (both for self and others). We also assessed the extent that forgetting, embarrassment/shame, and question irrelevance were perceived to be associated with under-reporting sexual behavior. RESULTS: Frames that focused on safety or a recipient resulted in people reporting being less deterred from donating. Regardless of frame, people from ethnic minorities were more likely to feel deterred. Embarrassment/shame followed by forgetting and perceived irrelevance were the main reasons for under-reporting sexual behaviors, especially in ethnic minorities, and smartphones were perceived as an acceptable memory aid for sexual behavior. DISCUSSION: Blood services moving to an individualized policy should frame donor selection in terms of safety and/or a recipient focus, explore sensitivities in ethnic minority communities, consider ways to normalize reporting sexual behavior, and use smartphones as a memory aid.

Reported non-compliance with pre-donation screening among blood donors in Québec, Canada: A focus on the 3-month deferral for men who have sex with men.

BACKGROUND AND OBJECTIVES: In Québec (Canada), the donation deferral for men who have sex with men (MSM) has recently been shortened to 3 months. Whether this change impacted compliance with pre-donation screening is unknown. We assessed compliance with the disclosure of male-to-male sex and other behavioural risk factors for HIV amid this change. MATERIALS AND METHODS: Québec residents who donated from 14 July 2020 to 30 November 2020 were invited to participate in an online survey. Donors were informed that the survey was optional and anonymous. Survey questions were those used for routine pre-donation screening. Rates of reported non-compliance were weighted based on several characteristics. RESULTS: Of 21,918 contacted donors, 7113 (32.45%) participated. Among male participants (N = 3347), six (0.27% [95% confidence interval (CI) = 0.09%-0.44%]) were not compliant with a 3-month MSM deferral. Among female participants (N = 3766), two (0.06% [95% CI = 0.00%-0.13%]) were not compliant with a 3-month deferral for sex with a man who had male-to-male sex ≤12 months. Other risk factors exhibited similar or lower rates of reported non-compliance. CONCLUSION: Reported non-compliance with a 3-month MSM deferral and the disclosure of other HIV behavioural risk factors was low. These results warrant the investigation of behavioural donor risk assessment approaches to further improve the inclusiveness of blood donation.

KIR in Allogeneic Hematopoietic Stem Cell Transplantation: Need for a Unified Paradigm for Donor Selection.

Allogeneic hematopoietic stem cell transplantation (aHSCT) is a lifesaving therapy for hematological malignancies. For years, a fully matched HLA donor was a requisite for the procedure. However, new immunosuppressive strategies have enabled the recruitment of viable alternative donors, particularly haploidentical donors. Over 95% of patients have at least two potential haploidentical donors available to them. To identify the best haploidentical donor, the assessment of new immunogenetic criteria could help. To this end, the clinical benefit of KIR genotyping in aHSCT has been widely studied but remains contentious. This review aims to evaluate the importance of KIR-driven NK cell alloreactivity in the context of aHSCT and explain potential reasons for the discrepancies in the literature. Here, through a non-systematic review, we highlight how the studies in this field and their respective predictive models or scoring strategies could be conceptually opposed, explaining why the role of NK cells remains unclear in aHCST outcomes. We evaluate the limitations of each published prediction model and describe how every scoring strategy to date only partly delivers the requirements for optimally effective NK cells in aHSCT. Finally, we propose approaches toward finding the optimal use of KIR genotyping in aHSCT for a unified criterion for donor selection.

Automated Segmentation of Kidney Cortex and Medulla in CT Images: A Multisite Evaluation Study.

BACKGROUND: In kidney transplantation, a contrast CT scan is obtained in the donor candidate to detect subclinical pathology in the kidney. Recent work from the Aging Kidney Anatomy study has characterized kidney, cortex, and medulla volumes using a manual image-processing tool. However, this technique is time consuming and impractical for clinical care, and thus, these measurements are not obtained during donor evaluations. This study proposes a fully automated segmentation approach for measuring kidney, cortex, and medulla volumes. METHODS: A total of 1930 contrast-enhanced CT exams with reference standard manual segmentations from one institution were used to develop the algorithm. A convolutional neural network model was trained (n=1238) and validated (n=306), and then evaluated in a hold-out test set of reference standard segmentations (n=386). After the initial evaluation, the algorithm was further tested on datasets originating from two external sites (n=1226). RESULTS: The automated model was found to perform on par with manual segmentation, with errors similar to interobserver variability with manual segmentation. Compared with the reference standard, the automated approach achieved a Dice similarity metric of 0.94 (right cortex), 0.90 (right medulla), 0.94 (left cortex), and 0.90 (left medulla) in the test set. Similar performance was observed when the algorithm was applied on the two external datasets. CONCLUSIONS: A fully automated approach for measuring cortex and medullary volumes in CT images of the kidneys has been established. This method may prove useful for a wide range of clinical applications.

Eligible neonatal donors after circulatory determination of death (Maastricht type III): A national survey of level III NICUs.

BACKGROUND: Organ donation continues to increase worldwide, but in general paediatric patients remain less likely to receive a transplant. The inclusion of neonates as donors after cDCD should be considered in an effort to increase donation rates. METHODS: The survey for a cross-sectional national study of potential cDCD neonatal donors (Maastricht type III) was sent to all 90 level III Spanish neonatal units to explore: 1) protocols, education, and specific opinions on donation and 2) potential cDCD that could have been eligible over a 2-year period (2014-2015). RESULTS: Forty-five centers (50%) completed the survey, and 38/45 gave information about potential eligible donors. In 16% of the centers specific protocols on neonatal donation exist. All hospitals demanded more specific training, and 65% noted that the donation process could be a problem in the family's dismissal of the child. During the study period 46 805 neonates were admitted in the 38 centers, and 625 neonates died. Ninety-five born at a gestational age ≥34 weeks and above 2000 gr died after an EoL decision, 38 (40%) and 13 (14%) of them due to neonatal encephalopathy and multiple congenital anomalies, respectively. There were 31 (33%) elegible infants who died in less than 120 min due to pathologies that did not contraindicate donation. CONCLUSIONS: Neonatal cDCD could help to reduce the gap between the supply of and demand for organs according to the potentially eligible patients emerging from this study. Training in EoL and donation processes should be provided to healthcare professionals.

Reversible glomerular damage in disseminated intravascular coagulation.

BACKGROUND: Brain death secondary to traumatic brain injury is one of the main sources of organs for transplantation but it can be associated with disseminated intravascular coagulation, which has been considered a relative contraindication for kidney donation. METHODS: We describe two successful pediatric cases of kidney transplantation from a single donor with disseminated intravascular coagulation. RESULTS: A 17-year-old male donor died from head injury and both kidneys were offered to our center. Within 24 h, donor's Hb and platelets dropped to 8.3 g/dl and 32 000/mcl, respectively, serum creatinine reached 2.01 mg/dl, and urinalysis showed proteinuria (300 mg/dl). Pre-implant biopsy showed massive occlusion of glomerular capillaries by fibrin thrombi containing fragmented red blood cells and inflammatory cells, and acute tubular damage. Arterioles and small arteries were spared. A diagnosis of DIC was made. The kidneys were transplanted in a 16-year-old girl and a 13-year-old boy. Slow recovery of graft function was observed in both recipients. On post-operative day 3, platelets dropped to a minimum value of 66 000 and 86 000/mcl, respectively. Diuresis was always present. On day 4, platelets started to rise. Six months later, both recipients attained normal renal function. A six-month protocol biopsy showed no microthrombi or other signs of disseminated intravascular coagulation. CONCLUSIONS: Despite the limited data available in literature, the outcome of these two cases is positive. Thus, pre-implant kidney biopsy, even if it reveals massive thrombotic occlusion of glomerular capillaries compatible with diagnosis of disseminated intravascular coagulation, should not be considered an absolute contraindication to transplantation.

Hematopoietic cell transplantation for sickle cell disease: updates and future directions.

Excellent outcomes in hematopoietic cell transplantation (HCT) from HLA-identical siblings, improvements in conditioning regimens, novel graft-versus-host disease prophylaxis, and the availability of alternative donors have all contributed to the increased applicability and acceptability of HCT for sickle cell disease (SCD). In young children with symptomatic SCD with an available HLA-identical related donor, HCT should be carefully considered. HCT from alternative donors is typically undertaken only in patients with severe symptoms, causing or likely to cause organ damage, and in the context of clinical trials. Patients undergoing HCT for SCD require careful counseling and preparation. They require careful monitoring of unique organ toxicities and complications during HCT. Patients must be prospectively followed for a prolonged time to determine the long-term outcomes and late effects of HCT for SCD. Thus, there is a need for a universal, longitudinal clinical registry to follow patients after HCT for SCD in conjunction with individuals who do not receive HCT to compare outcomes. Antibody-based conditioning and ex-vivo umbilical cord blood expansion are likely to improve the availability and acceptability of HCT. In addition, new disease-modifying drugs and the emerging option of the autologous transplantation of gene-modified hematopoietic progenitor cells are likely to expand the available therapeutic options and make decision-making by patients, physicians, and caregivers even more complicated. Future efforts must also focus on determining the impact of socioeconomic status on access to and outcomes of HCT and the long-term impact of HCT on patients, families, and society.

Development of the Eurotransplant Discard Risk Index to Predict Acceptance of Livers for Transplantation: A Retrospective Database Analysis.

OBJECTIVES: The utilization of liver allografts could be optimized if nonacceptance is predicted. This study aimed to evaluate the prognostic ability of an updated Discard Risk Index in Eurotransplant. MATERIALS AND METHODS: Potential deceased donors from January 2010 to December 2015 who had been reported to Eurotransplant were included in our analyses. Liver utilization was defined by transplant status as the primary outcome to evaluate the performance of the Eurotransplant-developed Discard Risk Index. RESULTS: Of 11670 potential livers, 9565 (81%) were actually transplanted. Donor sex, age, history of diabetes, drug abuse, use of vasopressors, body mass index category, serum sodium, cause of death, donor type, and levels of C-reactive protein, bilirubin, aspartate and alanine aminotransferases, international normalized ratio, and gamma-glutamyltranspeptidase were associated with discard and combined in the Eurotransplant-developed Discard Risk Index. Correlation between the two Discard Risk Indexes was high (r = 0.86), and both achieved high C statistics of 0.72 and 0.75 (P < .001), respectively. Despite strong calibration, discard rates of 0.8% for overall donors and 6% of donors after circulatory death could be predicted with 80% accuracy. CONCLUSIONS: The Eurotransplant-developed Discard Risk Index showed a high prognostic ability to predict liver utilization in a European setting. The model could therefore be valuable for identifying livers at high risk of not being transplanted in an early stage. These organs might profit the most from modified allocation strategies or advanced preservation techniques.

A comprehensive approach to stool donor screening for faecal microbiota transplantation in China.

BACKGROUND: Faecal microbiota transplantation (FMT) is an effective therapy for recurrent Clostridium difficile infections and chronic gastrointestional infections. However, the risks of FMT and the selection process of suitable donors remain insufficiently characterized. The eligibility rate for screening, underlying microbial basis, and core ethical issues of stool donors for FMT are yet to be elucidated in China. RESULTS: The potential stool donors were screened from December 2017 to December 2019 with the help of an online survey, clinical assessments, and stool and blood testing. Bioinformatics analyses were performed, and the composition and stability of gut microbiota in stool obtained from eligible donors were dynamically observed using metagenomics. Meanwhile, we build a donor microbial evaluation index (DoMEI) for stool donor screening. In the screening process, we also focused on ethical principles and requirements. Of the 2071 participants, 66 donors were selected via the screening process (3.19% success rate). Although there were significant differences in gut microbiota among donors, we found that the changes in the gut microbiota of the same donor were typically more stable than those between donors over time. CONCLUSIONS: DoMEI provides a potential reference index for regular stool donor re-evaluation. In this retrospective study, we summarised the donor recruitment and screening procedure ensuring the safety and tolerability for FMT in China. Based on the latest advances in this field, we carried out rigorous recommendation and method which can assist stool bank and clinicians to screen eligible stool donor for FMT.

[Residual risk for transfusion-transmitted hepatitis B virus infection due to occult hepatitis B virus infection in donors living in Yaoundé, Cameroon]. / Risque résiduel de la transmission par transfusion de l´infection du virus de l´hépatite B dû aux donneurs porteurs de l´infection du virus de l´hépatite B occulte à Yaoundé, Cameroun.

INTRODUCTION: viral infection caused by hepatitis B virus is the most frequent transfusion-transmitted viral infection. Although the search for hepatitis B surface antigen (HBsAg) in blood banks has significantly reduced the risk for transfusion-transmitted virus infection, there is still a residual transfusion risk of transmission from donors with occult hepatitis B. Blood bags containing aHBc with or without aHBs and viral DNA can cause infections and represent a threat to transfusion safety when aHBc levels are undetectable. The purpose of this study is to determine the residual risk for transfusion-transmitted hepatitis B virus at the Central Hospital of Yaoundé (CHY) as well as at the St Martin de Porres's Catholic Hospital (SMPCH) in Yaoundé, Cameroon. METHODS: we conducted a cross-sectional study among blood donors at the Central Hospital of Yaoundé (CHY) and the St Martin de Porres's Catholic Hospital. In these subjects the search for aHBc and/or the aHBs was conducted by immunochromatography. HBV DNA test was performed on blood samples tested positive for aHBc and/or aHBs by Polymerase Chain Reaction (PCR) technique using specific primers. RESULTS: out of a total of 193 blood donors negative for HIV, HBV (HBsAg), HCV serological markers and treponema infections, the overall seroprevalence of aHBc and/or aHBs was 9,84% (19/193). Out of a total of 19 potentially infected donors, HBV DNA was detected in 03 individuals, including 02 aHBc carriers and 01 carrier of both aHBc and aHBs, reflecting a prevalence of occult hepatitis B of 15,79% (3/19) [IC 95% =3,38%-39,58%] and a residual risk for transfusion-transmitted hepatitis B virus of 1,55% (3/193) [IC 95% =0,32%-4,48%]. CONCLUSION: this study shows that the residual risk for transfusion-transmitted hepatitis B virus is low. However, it is recommended to screan blood donors for aHBc and/or aHBs.

The consensus from The Chinese Society of Hematology on indications, conditioning regimens and donor selection for allogeneic hematopoietic stem cell transplantation: 2021 update.

The consensus recommendations in 2018 from The Chinese Society of Hematology (CSH) on indications, conditioning regimens and donor selection for allogeneic hematopoietic stem cell transplantation (allo-HSCT) facilitated the standardization of clinical practices of allo-HSCT in China and progressive integration with the world. There have been new developments since the initial publication. To integrate recent developments and further improve the consensus, a panel of experts from the CSH recently updated the consensus recommendations, which are summarized as follows: (1) there is a new algorithm for selecting appropriate donors for allo-HSCT candidates. Haploidentical donors (HIDs) are the preferred donor choice over matched sibling donors (MSDs) for patients with high-risk leukemia or elderly patients with young offspring donors in experienced centers. This replaces the previous algorithm for donor selection, which favored MSDs over HIDs. (2) Patients with refractory/relapsed lymphoblastic malignancies are now encouraged to undergo salvage treatment with novel immunotherapies prior to HSCT. (3) The consensus has been updated to reflect additional evidence for the application of allo-HSCT in specific groups of patients with hematological malignancies (intermediate-risk acute myeloid leukemia (AML), favorable-risk AML with positive minimal residual disease, and standard-risk acute lymphoblastic leukemia). (4) The consensus has been updated to reflect additional evidence for the application of HSCT in patients with nonmalignant diseases, such as severe aplastic anemia and inherited diseases. (5) The consensus has been updated to reflect additional evidence for the administration of anti-thymocyte globulin, granulocyte colony-stimulating factors and post-transplantation cyclophosphamide in HID-HSCT.

Next-generation sequencing and clinical histocompatibility testing.

Histocompatibility testing is essential for donor identification and risk assessment in solid organ and hematopoietic stem cell transplant. Additionally, it is useful for identifying donor specific alleles for monitoring donor specific antibodies in post-transplant patients. Next-generation sequence (NGS) based human leukocyte antigen (HLA) typing has improved many aspects of histocompatibility testing in hematopoietic stem cell and solid organ transplant. HLA disease association testing and research has also benefited from the advent of NGS technologies. In this review we discuss the current impact and future applications of NGS typing on clinical histocompatibility testing for transplant and non-transplant purposes.

Notifying donors when their deferral is ending: An effective donor retention strategy.

BACKGROUND: The application of a temporary deferral often leads to donor lapse. Contributing factors may be donors not knowing when their deferral ends or not being contacted and asked to return. The aim of this study was to determine the effectiveness of a reminder message notifying donors that their deferral is coming to an end in increasing donors' postdeferral return rates. We evaluated the optimal time, content, and mode of delivery of the reminder message. STUDY DESIGN AND METHODS: Two studies were conducted with deferred donors. Study 1: donors (n = 1676) were randomized to be sent a reminder message at one of three time points (4 weeks before, 1 week before, and 1 week after their deferral ended) or to a no contact control condition. Study 2: donors (n = 1973) were randomized to three message type conditions (emotive email, nonemotive email, nonemotive SMS). Attempted return behavior was extracted (appointments, attendances) at 1 month. RESULTS: In Study 1, being sent the reminder message increased odds of donors attempting to return within 3 months compared with the control group (OR:2.01). Sending the reminder 1 week before the deferral ended was the most effective time point. In Study 2, the nonemotive message increased the odds of attempting to return compared with the emotive message (OR:1.38). No differences were found between email and SMS messages. DISCUSSION: Sending a reminder message to donors when their deferral is coming to an end is a simple, effective, and cost-effective method to retain donors.

High Frequency Occult Hepatitis B Virus Infection Detected in Non-Resolved Donations Suggests the Requirement of Anti-HBc Test in Blood Donors in Southern China.

Background: Most Chinese Blood Centers adopted mini pool (MP) nucleic acid testing (NAT) for HBV screening due to high cost of Individual donation (ID) NAT, and different proportions of MP-reactive but ID-non-reactive donations (MP+/ID-, defined as non-resolved donations) have been observed during daily donor screening process. Some of these non-resolved donations are occult HBV infections (OBIs), which pose potential risk of HBV transmission if they are not deferred. This study is aimed to further analyze these non-resolved donations. Methods: The non-resolved plasma samples were further analyzed by serological tests and various HBV DNA amplification assays including quantitative PCR (qPCR) and nested PCR amplifying the basic core and pre-core promoter regions (BCP/PC; 295 base pairs) and HBsAg (S) region (496 base pairs). Molecular characterizations of HBV DNA+ non-resolved samples were determined by sequencing analysis. Results: Of 17,226 MPs from 103,356 seronegative blood donations, 98 MPs were detected reactive for HBV. Fifty-six out of these 98 (57.1%) reactive MPs were resolved as HBV DNA+, but the remaining 42 pools (42.9%, 252 donations) were left non-resolved with a high rate (53.2%) of anti-HBc+. Surprisingly, among 42 non-resolved MPs, 17 contained one donation identified as OBIs by alternative NAT assays. Sequence analysis on HBV DNAs extracted from these OBI donations showed some key mutations in the S region that may lead to failure in HBsAg detection and vaccine escape. Conclusion: A total of 53.2% of the non-resolved donations were anti-HBc+, and OBIs were identified in 40.5% of these non-resolved pools. Therefore, non-resolved donations with anti-HBc+ might pose potential risk for HBV transmission. Our present analysis indicates that anti-HBc testing in non-resolved donations should be used to identify OBIs in order to further increase blood safety in China.

How do I think about blood donor eligibility criteria for medical conditions?

Every blood center must determine blood donor eligibility criteria for donors with medical conditions, often based on very limited published data and variable practice. This manuscript briefly outlines possible impacts of donor medical conditions on donor and recipient safety and product quality, and describes the multidisciplinary approach used in Canada to think about donor criteria issues. Many years of experience are distilled into practical considerations in determining criteria, possible sources of information, and factors for successful change implementation, to hopefully assist medical and technical staff engaged in decision-making around donor eligibility.

Safe use of livers from deceased donors older than 70 years in recipients with HCV cirrhosis treated with direct-action antivirals. Retrospective cohort study.

INTRODUCTION: There is controversy regarding the use of older grafts for liver transplantation (LT) in HCV-infected patients, but the introduction of direct-acting antivirals (DAA) can radically change that debate. METHODS: The aim of this retrospective cohort study was to evaluate outcomes of the use of liver grafts from donors older than 70 years in recipients with HCV infection who underwent pre- or post-LT treatment with DAA. We compared two groups of patients who underwent LT using livers >70 years; the groups were defined according to antiviral therapy: non-DAA therapy group (n = 62; LT between May 1996 and December 2013), and DAA therapy group (n = 31; LT between January 2014 and December 2019). RESULTS: Thirty (96.8%) patients of DAA therapy and nine (14.5%) of non-DAA therapy (21 patients underwent complete therapy with interferon-ribavirin) achieved sustained viral response (SVR). One, 3-, and 5-year patient survival were 83.9%, 67.7%, and 56.5% in the non-DAA group vs 93.5%, 88.4%, and 88.4% in the DAA group (P = 0.04); the 1-, 3-, and 5-year graft survival were 77.4%, 62.9%, and 51.6% in the non-DAA group vs. 88.6%, 83.7%, and 83.7% in the DAA group (P = 0.03). Multivariate analysis demonstrated donor female sex and DAA therapy as protective factors of graft survival. CONCLUSIONS: Pre- or post-LT therapy with DAA in HCV-infected patients has achieved an almost overall SVR. The use of liver grafts >70 years in these patients treated with DAA was associated with significantly higher 5-year patient and graft survival in DAA group compared to non-DAA group. Thus, the introduction of DAA therapy has allowed the safe use of livers >70 years in HCV-positive recipients.