Point of care assay for blood aripiprazole concentrations: development, validation and utility.

BACKGROUND: The antipsychotic aripiprazole is often used in the treatment of first-episode psychosis. Measuring aripiprazole blood levels provides an objective measure of treatment adherence, but this currently involves taking a venous blood sample and sending to a laboratory for analysis. AIMS: To detail the development, validation and utility of a new point of care (POC) test for finger-stick capillary blood concentrations of aripiprazole. METHOD: Analytical performance (sensitivity, precision, recovery and linearity) of the assay were established using spiked whole blood and control samples of varying aripiprazole concentration. Assay validation was performed over a 14-month period starting in July 2021. Eligible patients were asked to provide a finger-stick capillary sample in addition to their usual venous blood sample. Capillary blood samples were tested by the MyCare™ Insite POC analyser, which provided measurement of aripiprazole concentration in 6 min, and the venous blood sample was tested by the standard laboratory method. RESULTS: A total of 101 patients agreed to measurements by the two methods. Venous blood aripiprazole concentrations as assessed by the laboratory method ranged from 17 to 909 ng/mL, and from 1 to 791 ng/mL using POC testing. The correlation coefficient between the two methods (r) was 0.96 and there was minimal bias (slope 0.91, intercept 4 ng/ml). CONCLUSIONS: The MyCare Insite POC analyser is sufficiently accurate and reliable for clinical use. The availability of this technology will improve the assessment of adherence to aripiprazole and the optimising of aripiprazole dosing.

The demise of islet allotransplantation in the United States: A call for an urgent regulatory update.

Islet allotransplantation in the United States (US) is facing an imminent demise. Despite nearly three decades of progress in the field, an archaic regulatory framework has stymied US clinical practice. Current regulations do not reflect the state-of-the-art in clinical or technical practices. In the US, islets are considered biologic drugs and "more than minimally manipulated" human cell and tissue products (HCT/Ps). In contrast, across the world, human islets are appropriately defined as "minimally manipulated tissue" and not regulated as a drug, which has led to islet allotransplantation (allo-ITx) becoming a standard-of-care procedure for selected patients with type 1 diabetes mellitus. This regulatory distinction impedes patient access to islets for transplantation in the US. As a result only 11 patients underwent allo-ITx in the US between 2016 and 2019, and all as investigational procedures in the settings of a clinical trials. Herein, we describe the current regulations pertaining to islet transplantation in the United States. We explore the progress which has been made in the field and demonstrate why the regulatory framework must be updated to both better reflect our current clinical practice and to deal with upcoming challenges. We propose specific updates to current regulations which are required for the renaissance of ethical, safe, effective, and affordable allo-ITx in the United States.

Efficacy and safety of bleselumab in kidney transplant recipients: A phase 2, randomized, open-label, noninferiority study.

This study assessed the efficacy and safety of the anti-CD40 monoclonal antibody bleselumab (ASKP1240) in de novo kidney transplant recipients over 36 months posttransplant. Transplant recipients were randomized (1:1:1) to standard of care (SoC: 0.1 mg/kg per day immediate-release tacrolimus [IR-TAC]; target minimum blood concentration [Ctrough ] 4-11 ng/mL plus 1 g mycophenolate mofetil [MMF] twice daily) or bleselumab (200 mg on days 0/7/14/28/42/56/70/90, and monthly thereafter) plus either MMF or IR-TAC (0.1 mg/kg per day; target Ctrough 4-11 ng/mL days 0-30, then 2-5 ng/mL). All received basiliximab induction (20 mg pretransplant and on days 3-5 posttransplant) and corticosteroids. One hundred thirty-eight transplant recipients received ≥1 dose of study drug (SoC [n = 48]; bleselumab + MMF [n = 46]; bleselumab + IR-TAC [n = 44]). For the primary endpoint (incidence of biopsy-proven acute rejection [BPAR] at 6 months), bleselumab + IR-TAC was noninferior to SoC (difference 2.8%; 95% confidence interval [CI] -8.1% to 13.8%), and bleselumab + MMF did not demonstrate noninferiority to SoC (difference 30.7%; 95% CI 15.2%-46.2%). BPAR incidence slightly increased through month 36 in all groups, with bleselumab + IR-TAC continuing to demonstrate noninferiority to SoC. Bleselumab had a favorable benefit-risk ratio. Most treatment-emergent adverse events were as expected for kidney transplant recipients (ClinicalTrials.gov NCT01780844).

Variability in assessing for BK viremia: whole blood is not reliable and plasma is not above reproach - a retrospective analysis.

Polyomavirus nephropathy (PVN) is a major complication of kidney transplantation. Most reports describe polyomavirus viremia either precedes or is detectable at the time of diagnosis of PVN. This association is the basis of current screening recommendations. We retrospectively reviewed the PCR results of blood and urine samples from 29 kidney transplant recipients with biopsy-proven PVN. Biopsies were performed for a rise in serum creatinine or persistent high-level BK viruria. All biopsies showed polyoma virus large T-antigen expression in tubular epithelium using immunohistochemistry. All had viruria preceding or at the time of biopsy (range, 5.2 × 104 to >25 × 106 BKV DNA copies/ml). Twenty (69%) had viremia ranging from 2.5 × 103 to 4.3 × 106 copies/ml at the time of the biopsy. Via blood BK PCR assay, nine (31%) had no BK viremia detected either preceding or at the time of the biopsy. In five recipients where sufficient specimen permitted, additional plasma BK assessment revealed positive detection of viremia. A comparative analysis of assays from two centres was performed with spiked samples. BK DNA may not be detected in the blood of some kidney transplant recipients with histologically confirmed PVN. This may reflect limitation of whole blood as opposed to plasma-based BK DNA assessment.

Acute mental health service use by patients with severe mental illness after discharge to primary care in South London.

BACKGROUND: To return the patients to primary care is arguably the desired service outcome for community mental health teams (CMHTs). AIMS: To assess acute mental health service use (hospitalisation or Home Treatment Team) by people with severe mental illness following discharge to primary care. METHOD: Retrospective cohort study comparing receipt and duration of acute care by 98 patients in the two years following discharge to primary care from CMHT, with a cohort of 92 patients transferred to another CMHT. RESULTS: The discharged group was significantly more stable on clinical measures. Fifty-seven (58.2%) patients were re-referred after median 39 weeks, with 35 (60.3%) in crisis. The difference in acute service use between discharged patients (27.9 days/patient) and transferred patients (31.7 days/patient) was not significant. Hospitalisation in the two years prior to discharge or transfer increased the odds of re-referral (OR 3.93, 95% CI 1.44-14.55), subsequent acute service use (OR 1.02, 95% CI 1.01-1.03) and duration of input (0.45 extra days/patient, 95% CI 0.22-0.68). CONCLUSIONS: The majority of the discharged patients were re-referred to mental health services. Although these were more stable, there was no difference from the transferred group on acute service use. Further support may be required in primary care to maintain stability.

Examining Hemodialysis Reliable Outflow catheter performance and cost in hemodialysis access.

BACKGROUND: The Hemodialysis Reliable Outflow (HeRO) vascular access device is a hybrid polytetrafluoroethylene graft-stent construct designed to address central venous occlusive disease. Although initial experience has demonstrated excellent mid-term patency rates, subsequent studies have led to external validity questions. The purpose of this study was to examine a single center experience with this vascular access device in challenging access cases with associated costs. METHODS: A retrospective study representing the authors' cumulative HeRO vascular access device experience was undertaken. The primary endpoint was graft failure or death, with secondary endpoints including secondary intervention rates and cost. RESULTS: Forty-one patients with 15,579 HeRO days and a mean of 12.7 ± 1.5 mo with the vascular access device were available for analysis. Secondary patency was 81.6% at 6 mo and 53.7% at 12 mo. The reintervention rate was 2.84 procedures per HeRO vascular access device year. Associated HeRO costs related to subsequent procedures were estimated at $34,713.63 per patient/y. CONCLUSIONS: These data on the patency and primary outcome data diverge significantly from initial multicenter studies and represent a real-world application of this technology. It is costly to maintain patency. Use of HeRO vascular access devices should be judicious with outcome expectations reduced.

Antegrade persufflation of porcine kidneys improves renal function after warm ischemia.

Introduction: Transplantation of kidneys from expanded criteria donors (ECD), including after circulatory death (DCD), is associated with a higher risk of adverse events compared to kidneys from standard criteria donors. In previous studies, improvements in renal transplant outcomes have been seen when kidneys were perfused with gaseous oxygen during preservation (persufflation, PSF). In the present study, we assessed ex-vivo renal function from a Diffusion Contrast Enhanced (DCE)-MRI estimation of glomerular filtration rate (eGFR); and metabolic sufficiency from whole-organ oxygen consumption (WOOCR) and lactate production rates. Methods: Using a porcine model of DCD, we assigned one kidney to antegrade PSF, and the contralateral kidney to static cold storage (SCS), both maintained for 24 h at 4°C. Post-preservation organ quality assessments, including eGFR, WOOCR and lactate production, were measured under cold perfusion conditions, and biopsies were subsequently taken for histopathological analysis. Results: A significantly higher eGFR (36.6 ± 12.1 vs. 11.8 ± 4.3 ml/min, p < 0.05), WOOCR (182 ± 33 vs. 132 ± 21 nmol/min*g, p < 0.05), and lower rates of lactate production were observed in persufflated kidneys. No overt morphological differences were observed between the two preservation methods. Conclusion: These data suggest that antegrade PSF is more effective in preserving renal function than conventional SCS. Further studies in large animal models of transplantation are required to investigate whether integration with PSF of WOOCR, eGFR or lactate production measurements before transplantation are predictive of post-transplantation renal function and clinical outcomes.

Unraveling ethnic disparities in antipsychotic prescribing among patients with psychosis: A retrospective cohort study based on electronic clinical records.

BACKGROUND: Previous studies have shown mixed evidence on ethnic disparities in antipsychotic prescribing among patients with psychosis in the UK, partly due to small sample sizes. This study aimed to examine the current state of antipsychotic prescription with respect to patient ethnicity among the entire population known to a large UK mental health trust with non-affective psychosis, adjusting for multiple potential risk factors. METHODS: This retrospective cohort study included all patients (N = 19,291) who were aged 18 years or over at their first diagnoses of non-affective psychosis (identified with the ICD-10 codes of F20-F29) recorded in electronic health records (EHRs) at the South London and Maudsley NHS Trust until March 2021. The most recently recorded antipsychotic treatments and patient attributes were extracted from EHRs, including both structured fields and free-text fields processed using natural language processing applications. Multivariable logistic regression models were used to calculate the odds ratios (OR) for antipsychotic prescription according to patient ethnicity, adjusted for multiple potential contributing factors, including demographic (age and gender), clinical (diagnoses, duration of illness, service use and history of cannabis use), socioeconomic factors (level of deprivation and own-group ethnic density in the area of residence) and temporal changes in clinical guidelines (date of prescription). RESULTS: The cohort consisted of 43.10 % White, 8.31 % Asian, 40.80 % Black, 2.64 % Mixed, and 5.14 % of patients from Other ethnicity. Among them, 92.62 % had recorded antipsychotic receipt, where 24.05 % for depot antipsychotics and 81.72 % for second-generation antipsychotic (SGA) medications. Most ethnic minority groups were not significantly different from White patients in receiving any antipsychotic. Among those receiving antipsychotic prescribing, Black patients were more likely to be prescribed depot (adjusted OR 1.29, 95 % confidence interval (CI) 1.14-1.47), but less likely to receive SGA (adjusted OR 0.85, 95 % CI 0.74-0.97), olanzapine (OR 0.82, 95 % CI 0.73-0.92) and clozapine (adjusted OR 0.71, 95 % CI 0.6-0.85) than White patients. All the ethnic minority groups were less likely to be prescribed olanzapine than the White group. CONCLUSIONS: Black patients with psychosis had a distinct pattern in antipsychotic prescription, with less use of SGA, including olanzapine and clozapine, but more use of depot antipsychotics, even when adjusting for the effects of multiple demographic, clinical and socioeconomic factors. Further research is required to understand the sources of these ethnic disparities and eliminate care inequalities.

Reducing the Risk of Withdrawal Symptoms and Relapse Following Clozapine Discontinuation-Is It Feasible to Develop Evidence-Based Guidelines?

Clozapine is the only antipsychotic that is effective in treatment-resistant schizophrenia. However, in certain clinical situations, such as the emergence of serious adverse effects, it is necessary to discontinue clozapine. Stopping clozapine treatment poses a particular challenge due to the risk of psychotic relapse, as well as the development of withdrawal symptoms. Despite these challenges for the clinician, there is currently no formal guidance on how to safely to discontinue clozapine. We assessed the feasibility of developing evidence-based recommendations for (1) minimizing the risk of withdrawal symptoms, (2) managing withdrawal phenomena, and (3) commencing alternatives treatment when clozapine is discontinued. We then evaluated the recommendations against the Appraisal of Guidelines for Research and Evaluation (AGREE) II criteria. We produced 19 recommendations. The majority of these recommendation were evidence-based, although the strength of some recommendations was limited by a reliance of studies of medium to low quality. We discuss next steps in the refinement and validation of an evidence-based guideline for stopping clozapine and identify key outstanding questions.

Clozapine for treatment resistance in early psychosis: a survey of UK clinicians' training, knowledge and confidence.

Background: Clozapine is the only medication licenced for patients with psychosis that is resistant to conventional antipsychotic treatment. However, despite its effectiveness, it remains widely underutilised. One contributory factor for this may be clinicians' lack of confidence around the management of clozapine. Objective: We conducted a survey of clinicians working in Early Intervention in Psychosis (EIP) services to determine their training needs for clozapine management in EIP services. Methods: An electronic survey was made available to all clinicians working in EIP services in England. The survey assessed confidence and training needs regarding managing clozapine in patients with treatment-resistant psychosis. Quantitative data were analysed using total mean scores and the Mann-Whitney U test. Results: In all, 192 (27%) of approximately 700 clinicians from 35 EIP services completed the survey. Approximately half (54%) had not received training on treatment with clozapine. Experience of training was higher in prescribers than non-prescribers, and among medical than non-medical clinicians. Previous training was associated with significantly higher confidence in offering clozapine and managing treatment-resistant psychosis (p < 0.001). Confidence levels with managing treatment-resistant psychosis and clozapine were relatively high (mean = 4 out of 5, SD = 1). Respondents were most confident about monitoring mental health response to treatment (mean = 5, SD = 1). Participants were least confident about how to discontinue clozapine treatment safely (mean = 3, SD = 1). Conclusion: Most clinicians working in EIP have not received training on the use of clozapine. This may account, in part, for the underutilisation of clozapine in EIP services. The provision of training in the identification of treatment-resistant psychosis and the use of clozapine will likely improve the detection and management of treatment resistance in the early phase of psychosis.

Impact of the COVID-19 pandemic on remote mental healthcare and prescribing in psychiatry: an electronic health record study.

OBJECTIVES: The recent COVID-19 pandemic has disrupted mental healthcare delivery, with many services shifting from in-person to remote patient contact. We investigated the impact of the pandemic on the use of remote consultation and on the prescribing of psychiatric medications. DESIGN AND SETTING: The Clinical Record Interactive Search tool was used to examine deidentified electronic health records of people receiving mental healthcare from the South London and Maudsley (SLaM) NHS Foundation Trust. Data from the period before and after the onset of the pandemic were analysed using linear regression, and visualised using locally estimated scatterplot smoothing. PARTICIPANTS: All patients receiving care from SLaM between 7 January 2019 and 20 September 2020 (around 37 500 patients per week). OUTCOME MEASURES: (i) The number of clinical contacts (in-person, remote or non-attended) with mental healthcare professionals per week.(ii) Prescribing of antipsychotic and mood stabiliser medications per week. RESULTS: Following the onset of the pandemic, the frequency of in-person contacts was significantly reduced compared with that in the previous year (ß coefficient: -5829.6 contacts, 95% CI -6919.5 to -4739.6, p<0.001), while the frequency of remote contacts significantly increased (ß coefficient: 3338.5 contacts, 95% CI 3074.4 to 3602.7, p<0.001). Rates of remote consultation were lower in older adults than in working age adults, children and adolescents. Despite this change in the type of patient contact, antipsychotic and mood stabiliser prescribing remained at similar levels. CONCLUSIONS: The COVID-19 pandemic has been associated with a marked increase in remote consultation, particularly among younger patients. However, there was no evidence that this has led to changes in psychiatric prescribing. Nevertheless, further work is needed to ensure that older patients are able to access mental healthcare remotely.

Point-of-care measurement of clozapine concentration using a finger-stick blood sample.

BACKGROUND: The use of clozapine demands regular monitoring of clozapine plasma concentrations and of white blood cell parameters. The delay between sending blood samples for analysis and receiving the results hinders clinical care. Point-of-care testing (POCT) can provide drug assay results within a few minutes. AIM: This study aimed to investigate the utility of a novel point-of-care device that can measure clozapine concentrations using capillary blood samples collected via a finger stick. METHOD: During a five-week period starting in June 2019 eligible patients were asked to provide a finger-stick capillary sample in addition to their usual venous blood sample. Samples were analysed by the novel point-of-care device and by the standard laboratory method. Capillary blood samples were tested by the MyCare™ Insite POCT analyser, and a quantitative measurement of clozapine concentration was provided within six minutes. RESULTS: A total of 309 patients agreed to measurements by the two methods. Analysis revealed clozapine concentrations in venous blood as determined by the laboratory method ranged from 20 to 1310 ng/mL and by POCT from 7 to 1425 ng/mL. There was a strong positive correlation (R = 0.89) between the results from the venous and the capillary sample methods. The slope of the association between standard assay and MyCare™ Insite was 1.0 with an intercept of -21 ng/mL, indicating minimal bias. CONCLUSION: Clozapine concentrations can be accurately measured at the point of care using capillary blood samples collected via a finger stick. This approach may be more acceptable than venous sampling to patients and, with almost instant results available, more useful to clinicians.

Arguments against the Requirement of a Biological License Application for Human Pancreatic Islets: The Position Statement of the Islets for US Collaborative Presented during the FDA Advisory Committee Meeting.

The Food and Drug Administration (FDA) has been regulating human islets for allotransplantation as a biologic drug in the US. Consequently, the requirement of a biological license application (BLA) approval before clinical use of islet transplantation as a standard of care procedure has stalled the development of the field for the last 20 years. Herein, we provide our commentary to the multiple FDA's position papers and guidance for industry arguing that BLA requirement has been inappropriately applied to allogeneic islets, which was delivered to the FDA Cellular, Tissue and Gene Therapies Advisory Committee on 15 April 2021. We provided evidence that BLA requirement and drug related regulations are inadequate in reassuring islet product quality and potency as well as patient safety and clinical outcomes. As leaders in the field of transplantation and endocrinology under the "Islets for US Collaborative" designation, we examined the current regulatory status of islet transplantation in the US and identified several anticipated negative consequences of the BLA approval. In our commentary we also offer an alternative pathway for islet transplantation under the regulatory framework for organ transplantation, which would address deficiencies of in current system.

Cultural influences on perception of disability and disabled people: a comparison of opinions from students in the United Kingdom (UK) Pakistan (PAK) about a generic wheelchair using a semantic differential scale.

Assistive Technology (AT) product use occurs within a socio-cultural setting. The growth internationally in the AT product market suggests that designers need to be aware of the influences that diverse cultures may have on the societal perception of an AT product through its semantic attributes. The study aimed to evaluate the visual interaction with an AT product by young adults from Pakistan, a collectivist society, and the United Kingdom (UK), an individualist society. A paper-based questionnaire survey was carried out with 281 first-year undergraduate students from the UK and Pakistan to evaluate their perception towards the visual representation of a generic conventional wheelchair image. A semantics differential (SD) scale method was used involving a seven-point bipolar SD scale incorporating sixteen pairs of adjectives defining functional, meaning, and usability attributes of the product. The mean (M) and standard deviation (sd) values were obtained for each pair of adjectives and compared between both groups by employing appropriate parametric tests. The results show that having a diverse cultural background did not appear to have overtly influenced the meanings ascribed to the generic manual wheelchair, which was unexpected. The University 'Internationalist' environment may have influenced the results. Some minor but critical differences were found for some pairs of adjectives (bulky-compact, heavy-light), having p-value less than .05 (p < .05) that related to previous experience of wheelchairs and/or their use. Further studies are planned to investigate and validate outcomes with other student and non-student groups.Implications for RehabilitationThe semantic attributes of assistive technologies highlight a number of aspects that have implications for those involved in Assistive Technology (AT) product development, manufacturing and marketing.• For online sales, the AT products rely on the web page image to communicate the purpose and attributes of the product. There are limited explorations related to the semantic/communicative attributes of AT product presented in images, as perceived by individuals from diverse cultural backgrounds.• The knowledge towards semantic meaning ascribed to the AT product is important to investigate to provide a perspective that goes beyond practical functions of the AT product towards the communicative function.• Information of comprehending semantics and significance of the AT product from a social (non-users) viewpoint may benefits manufacturers in the development of AT products that best meet the societal needs, preferences and expectations.• A model of best practice, with a focus on semantic manipulation will offer Industrial Designers (ID) internationally with the suitable process and tools to reframe perceptions of disability and enhance acceptance of AT products not only for users, but also for the society around them.

The influence of social context on the perception of assistive technology: using a semantic differential scale to compare young adults' views from the United Kingdom and Pakistan.

Background and aim: A Society's view of disability may influence the perception and use of Assistive Technology (AT) products. Semantic cues or cultural coding provide the viewer with a series of visual stimuli to be given or ascribed meaning. Previous research has shown cognitive approaches to visual perception and assignment of meaning vary between diverse cultures. This study reviews the influence of contextual settings on perception, to provide the basis for a debate on the societal perception of communicative content (semantic/meaning) of an AT product; and, the relevance of different cultural cognitive styles. The paper explores, from a cultural viewpoint, the overall understanding of disability internationally.Method: A Semantic Differential (SD) scale was used to obtain views on the image of an attendant wheelchair from nine hundred and ninety-one (991) young adults from the United Kingdom (UK) and Pakistan (PAK), reflecting the individualist and collectivist societies, respectively. This survey follows a previous paper-based study using the same image and protocol. Comparing the two surveys, a consensus of views from the two groups was achieved.Results and conclusion: The responses from the UK group were skewed towards a negative view of disability compared to the Pakistan group. This inferred greater social stigma associated with this AT product in the UK. The combined findings from both surveys provide insights into societal perception of AT products and disability. Areas for future research are suggested, including what visual components of an AT product (graphemes) appear to be associated with positive or negative responses for collectivist and individual societal groups.Implications for rehabilitationAssistive Technology (AT) product designers, academics, professionals and stakeholders need to be aware of challenges which are originated from one's socio-cultural environment. AT products convey certain meanings, semantics, which are interpreted by the society and are subjective to a specific cultural setting.•For the effective communication of meanings and values an AT product relies on the visual clues and design features embedded within the design. However, there have been a limited number of studies reviewing this aspect of product semantics.•The survey and associated testing has highlighted the differences in cultural perception towards AT products and demonstrated the importance of effectively designing the semantic attributes of an AT product as well as its function.•The demonstration of the efficacy of methods within the study for exploring the interpretation of semantic attributes of AT products will help designers and developers better understand the perceptions of individual cultures and societal groups.•A better understanding of different cultures and societies will enable designers and clinicians who specify AT products to reduce AT product abandonment; and, the associated stigma around disability.

Predicting high-cost care in a mental health setting.

BACKGROUND: The density of information in digital health records offers new potential opportunities for automated prediction of cost-relevant outcomes. AIMS: We investigated the extent to which routinely recorded data held in the electronic health record (EHR) predict priority service outcomes and whether natural language processing tools enhance the predictions. We evaluated three high priority outcomes: in-patient duration, readmission following in-patient care and high service cost after first presentation. METHOD: We used data obtained from a clinical database derived from the EHR of a large mental healthcare provider within the UK. We combined structured data with text-derived data relating to diagnosis statements, medication and psychiatric symptomatology. Predictors of the three different clinical outcomes were modelled using logistic regression with performance evaluated against a validation set to derive areas under receiver operating characteristic curves. RESULTS: In validation samples, the full models (using all available data) achieved areas under receiver operating characteristic curves between 0.59 and 0.85 (in-patient duration 0.63, readmission 0.59, high service use 0.85). Adding natural language processing-derived data to the models increased the variance explained across all clinical scenarios (observed increase in r2 = 12-46%). CONCLUSIONS: EHR data offer the potential to improve routine clinical predictions by utilising previously inaccessible data. Of our scenarios, prediction of high service use after initial presentation achieved the highest performance.

Oxygen Perfusion (Persufflation) of Human Pancreata Enhances Insulin Secretion and Attenuates Islet Proinflammatory Signaling.

BACKGROUND: All human islets used in research and for the clinical treatment of diabetes are subject to ischemic damage during pancreas procurement, preservation, and islet isolation. A major factor influencing islet function is exposure of pancreata to cold ischemia during unavoidable windows of preservation by static cold storage (SCS). Improved preservation methods may prevent this functional deterioration. In the present study, we investigated whether pancreas preservation by gaseous oxygen perfusion (persufflation) better preserved islet function versus SCS. METHODS: Human pancreata were preserved by SCS or by persufflation in combination with SCS. Islets were subsequently isolated, and preparations in each group matched for SCS or total preservation time were compared using dynamic glucose-stimulated insulin secretion as a measure of ß-cell function and RNA sequencing to elucidate transcriptomic changes. RESULTS: Persufflated pancreata had reduced SCS time, which resulted in islets with higher glucose-stimulated insulin secretion compared to islets from SCS only pancreata. RNA sequencing of islets from persufflated pancreata identified reduced inflammatory and greater metabolic gene expression, consistent with expectations of reducing cold ischemic exposure. Portions of these transcriptional responses were not associated with time spent in SCS and were attributable to pancreatic reoxygenation. Furthermore, persufflation extended the total preservation time by 50% without any detectable decline in islet function or viability. CONCLUSIONS: These data demonstrate that pancreas preservation by persufflation rather than SCS before islet isolation reduces inflammatory responses and promotes metabolic pathways in human islets, which results in improved ß cell function.

Probabilistic risk assessment of accidental ABO-incompatible thoracic organ transplantation before and after 2003.

BACKGROUND: A widely reported ABO-mismatch accident in March of 2003 raised concerns about the reliability of the transplantation system. Because this type of failure is rare and significant, we performed a probabilistic risk assessment (PRA) of the donor-recipient matching processes for thoracic organ transplantation. METHODS: A probabilistic risk assessment was performed. RESULTS: The likelihood of accidental incompatible implantation was already low in 2003. The PRA model indicates that the likelihood of such an event was 1.38x10 per donated organ. This estimate correlates closely with the observed rate of these accidents. Based on this model, process changes put in place shortly after the accident reduced the probability to approximately 3.08x10 and changes put in place in October 2004 further reduced the probability to approximately 2.22x10 per organ donated. CONCLUSIONS: The observed and predicted likelihoods of accidental incompatible thoracic organ transplantation are comparable. These likelihoods are several orders of magnitude smaller than other hazards associated with solid organ transplantation. The PRA model indicates that changes that followed the March 2003 accident further reduced the likelihood of accidental incompatible implantation by roughly two orders of magnitude. Quantitative estimates from PRA can be used to assess risks in healthcare and to gauge the impact of system changes on these risks.

Treatment of renal allograft polyoma BK virus infection with leflunomide.

BACKGROUND: Polyoma BK virus produces an aggressively destructive nephropathy in approximately 3% to 8% of renal allografts, is associated with graft loss within one year in 35% to 67% of those infected and there is no therapy of proven efficacy. Leflunomide is an immune suppressive drug with anti viral activity in vitro and in animals. METHODS: We treated twenty-six patients with biopsy proven NK virus nephropathy (BKN) with either leflunomide alone (n=17) or leflunomide plus a course of cidofovir (n=9) and followed them for six to forty months. Leflunomide was dosed to a targeted blood level of active metabolite, A77 1726, of 50 microg/ml to 100 microg/ml (150 microM to 300 microM). Response to treatment was gauged by serial determinations of viral load in blood and urine (PCR), serum creatinine, and repeat allograft biopsy. RESULTS: In the 22 patients consistently sustaining the targeted blood levels of active drug, blood and urine viral load levels uniformly decreased over time (P<.001). Mean serum creatinine levels stabilized over the first six months of treatment, and with 12 months or more of follow-up in 16 patients the mean serum creatinine has not changed significantly from base line. Four patients who did not consistently have blood levels of active drug (A77 1726) above 40 microg/ml did not clear the virus until these levels were attained or cidofovir was added. CONCLUSIONS: Leflunomide inhibits Polyoma virus replication in vitro and closely monitored leflunomide therapy with specifically targeted blood levels appears to be a safe and effective treatment for Polyoma BK nephropathy.

Case report: robot-assisted laparoscopic pyeloureterostomy in a transplanted kidney with ureteral stricture.

Ureteral obstruction secondary to ischemia is the most common urologic complication of kidney transplantation. Although endoscopic management has shown satisfactory short-term success rates, surgical repair is considered the definitive therapy. To our knowledge, this procedure has been performed only through open surgery. We present a minimally invasive approach for reconstruction of a ureteral stricture in a renal transplant patient using the Da Vinci robotic system.