Mycophenolate mofetil hampers antibody responses to a broad range of vaccinations in kidney transplant recipients: Results from a randomized controlled study

OBJECTIVES

To study the effect of mycophenolate mofetil (MMF) on various vaccination responses in kidney transplant recipients.

METHODS

In a randomized controlled trial (EudraCT nr.: 2014-001372-66), low immunologically risk kidney transplant recipients were randomized to TAC/MMF or TAC-monotherapy (TACmono), six months post-transplantation. One year after transplantation, in a pre-specified sub-study, recipients were vaccinated against pneumococcus, tetanus and influenza. Blood was sampled before and 21 days after vaccination. Adequate vaccination responses were defined by international criteria. A post-hoc analysis was conducted on SARS-CoV-2 vaccination responses within the same cohort.

RESULTS

Seventy-one recipients received pneumococcal and tetanus vaccines (TAC/MMF: n = 37, TACmono: n = 34), with 29 also vaccinated against influenza. When vaccinated, recipients were 60 (54-66) years old, with median eGFR of 54 (44-67) ml/min, tacrolimus trough levels 6.1 (5.4-7.0) ug/L in both groups and TAC/MMF daily MMF dose of 1000 (500-2000) mg. Adequate vaccination responses were: pneumococcal (TAC/MMF 43%, TACmono 74%, p = 0.016), tetanus (TAC/MMF 35%, TACmono 82%, p < 0.0001) and influenza (TAC/MMF 20%, TACmono 71%, p = 0.0092). Only 7% of TAC/MMF responded adequately to all three compared to 36% of TACmono (p = 0.080). Additionally, 40% of TAC/MMF responded inadequately to all three, whereas all TACmono patients responded adequately to at least one vaccination (p = 0.041). Lower SARS-CoV-2 vaccination antibody responses correlated with lower pneumococcal antibody vaccination responses (correlation coefficient: 0.41, p = 0.040).

CONCLUSIONS

MMF on top of tacrolimus severely hampers antibody responses to a broad range of vaccinations.

The mast cell: A Janus in kidney transplants

Mast cells (MCs) are innate immune cells with a versatile set of functionalities, enabling them to orchestrate immune responses in various ways. Aside from their known role in allergy, they also partake in both allograft tolerance and rejection through interaction with regulatory T cells, effector T cells, B cells and degranulation of cytokines and other mediators. MC mediators have both pro- and anti-inflammatory actions, but overall lean towards pro-fibrotic pathways. Paradoxically, they are also seen as having potential protective effects in tissue remodeling post-injury. This manuscript elaborates on current knowledge of the functional diversity of mast cells in kidney transplants, combining theory and practice into a MC model stipulating both protective and harmful capabilities in the kidney transplant setting.

Mesenchymal stromal cell therapy with early tacrolimus withdrawal prevents left atrial remodelling in renal transplant recipients: an analysis of the TRITON trial

Background

After renal transplantation, there is a need for immunosuppressive regimens that effectively prevent allograft rejection, while minimizing cardiovascular side effects. The TRITON study is the first randomized clinical trial that tested a strategy with autologous bone marrow derived mesenchymal stromal cell (MSC) therapy and complete withdrawal of calcineurin inhibitors (CNIs). The combination of MSC therapy and CNIs discontinuation was associated with improved blood pression control and regression of left ventricular hypertrophy. Nevertheless, the impact of this immunosuppressive strategy on left atrial (LA) structural and functional remodelling, which has been proven as an independent predictor of cardiovascular outcomes, has not been investigated.

Purpose

To assess the effects of MSC therapy combined with CNIs withdrawal on longitudinal changes of LA structure and function, evaluated by two-dimensional transthoracic echocardiography.

Methods

The TRITON trial randomized renal transplant recipients to MSC therapy – infused at week 6 and 7 after transplantation, with complete withdrawal at week 8 of tacrolimus (MSC group) – or standard tacrolimus dose (control group). Patients who underwent transthoracic echocardiography with speckle-tracking analysis at week 4 and 24 after renal transplantation were included in this sub-analysis. Changes in echocardiographic variables between 4 and 24 weeks post-transplantation were evaluated and compared between randomization arms using an analysis of covariance model, adjusted for baseline variable.

Results

54 patients (MSC group =27; control group =27) were included. Between 4 and 24 weeks after transplantation, an increase in indexed minimal LA volume (LAVImin) was observed in the control group, whereas in the MSC group there were no changes in LAVImin over the time, leading to a significant difference between groups (p=0.021). Moreover, patients randomized to MSC therapy showed a benefit in LA function, assessed by a significant interaction between changes in LA emptying fraction (LAEF) and LA reservoir strain and the treatment group (p=0.012 and p=0.027, respectively) (Table 1).

The association between changes in LA structural and functional parameters and the randomization arm remained significant after adjustment for changes in systolic blood pressure, diastolic blood pressure and estimated glomerular filtration rate over the time (Figure 1).

Conclusion

The combination of MSC therapy and early CNIs withdrawal prevents LA structural and functional remodelling in the first six months after renal transplantation. MSC therapy appears a promising approach in renal transplant recipient, effective in the prevention of graft rejection, while exerting potential cardioprotective effects.

Funding Acknowledgement

Type of funding sources: None.

Bio-distribution and longevity of mesenchymal stromal cell derived membrane particles

Vesicle-based medicines hold great promise for therapy development but essential knowledge on the bio-distribution and longevity of vesicles after administration is lacking. We generated vesicles from the membranes of human mesenchymal stromal cells (MSC) and we demonstrated earlier that these so-called membrane particles (MP) mediate immunomodulatory and regenerative responses in target cells. In the present study we examined the bio-distribution and longevity of MP after intravenous administration in mice. While most vesicle tracking methods are based on imaging techniques, which require labeling of vesicles and can only detect dense accumulations of vesicles, we used proteomics analysis to detect the presence of MP-derived proteins in multiple organs and tissues. MP proteins were mainly present in plasma and leukocytes at 1 h after injection, indicating that MP - in contrast to whole MSC - do not accumulate in the lungs upon first passage but remain in circulation. After 24 h, MP proteins were still present in plasma but were most abundant in the liver. RNA sequencing of livers demonstrated that MP impact liver function and in particular induce metabolic pathways. These data provide a clear view of the bio-distribution and longevity of MP, which is likely extrapolatable to other types of vesicles, and demonstrate that MP circulate for up to 24 h and may be a tool for targeting the liver.

POS0570 UNSUPERVISED DEEP-LEARNING IDENTIFIES SIX CLINICAL SUBTYPES OF RHEUMATOID ARTHRITIS AT BASELINE THAT ASSOCIATE WITH METHOTREXATE FAILURE DURING FOLLOW-UP

Background

Currently methotrexate (MTX) is the prevailing baseline treatment for Rheumatoid Arthritis (RA). Treatment response varies since RA is a highly heterogeneous disease. A tantalizing idea is that the factors causing clinical heterogeneity can already be elucidated at baseline.

Objectives

Disentangle clinical heterogeneity of RA patients at baseline to identify likely MTX failure during follow-up.

Methods

We constructed patient-specific profiles, featuring baseline clinical measurements which we split into three layers: 1) joint counts, 2) numerical hematology work up, and 3) categorical features (binary serological markers (aCCP/RF) and localization of joint inflammation and tenderness). We applied Z-score scaling on the numerical data and one hot encoding on the categorical features. To identify hidden structure across these layers we used Maui (Multi-omics Autoencoder Integration) [1], and Phenograph [2] for subsequent clustering of patients within the extracted latent space. We examined the most discriminatory features post-hoc with SHAP. With Kaplan Meier curves we assessed MTX efficacy using treatment switch as proxy for failure. We calculated hazard ratios (HR) with univariate Cox-regression.

Results

We had 944 RA patients with baseline health record data. MAUI identified 23 latent factors from 335 baseline variables. Phenograph showed 6 RA-subgroups (Table 1 & Figure 1).

Table 1.

Baseline characteristics of the different clusters

C1C2C3C4C5C6N22417917116211692Sex (F)*131 (59)122 (68)125 (73)112 (69)71 (61)57 (62)RF*95 (42)89 (50)106 (62)107 (66)68 (59)55 (60)aCCP*82 (36.6)89 (50)110 (64)105 (65)65 (56)54 (59)DAS44(3)3.6 (2.7-4.2)2.7 (2.2-3.1)2.4 (1.9-2.9)2.1 (1.7-2.6)2.2 (1.7-2.6)2.8 (2.4-3.2)SJC15 (11-20)6 (3-8)9.0 (6-12)2 (1-5)4 (2-6)9 (6-12)TJC19 (14-27)9 (6-12)12.0 (9-18)4 (2-6)3 (2-6)11 (7-13)ESR (mm/hr)33 (14-53)33 (14-48)19 (9-35)28 (14-39)23 (11-38)25 (9-36)Age (yr)63 (14)60 (13)53 (16)59 (15)63 (13)58 (16)MTX prescription*192 (85)146 (81)138 (80)131 (80)88 (75)78 (85)Follow up (days)1308 (743-2060)1458 (880-2567)1821 (982-2566)1590 (1022-2245)1566 (787-2000)1468 (832-2211)Symptom duration (days)124 (52-334)155 (46-537)155 (62-365)217 (77-775)186 (62-548)155 (62-365)

Presented are *binary variables as n(%) and continuous as median (Q1-Q3) or mean (SD).

Figure 1.

Overview of the distinct RA-clusters: A) 2D UMAP, B) Kaplan Meier plot of MTX-probability across 8.6 years (defined by cluster with shortest follow up), C) SHAP plot of most discriminatory features per cluster.

The baseline clusters (C) are characterized by a different joint involvement or lab value: C1 had a low aCCP-positivity (37%) and high median ESR of 33. C1 had the most affected joints (primarily the small joints) with a swollen- (SJC) and tender joint count (TJC) of 15 and 19 respectively. C2 had mediocre aCCP-positivity (50%) and low median SJC=6 and TJC=9. C3 had MTP involvement, high aCCP-positivity (64%), and low ESR=19 but relatively high joint counts; SJC=9 and TJC=12. C4 had no wrists, high aCCP-positivity (65%), high ESR=28 and low joint counts; SJC=2, TJC=4. C5 had low lymphocyte numbers and a low median ESR=23, SJC=4 and TJC=3. C6 had MCP1 involvement, was mostly aCCP-positive (59%) and had a slightly higher median ESR=25, SJC=9 and TJC=11.

Clusters differed in MTX failure: 40%, 53%, 69%, 54%, 48% and 64% (for cluster 1-6, P=3.2e-2). Examining the local differences, we observed the biggest difference between C1 and C3 (HR 0.5 (95% CI 0.36-0.7), P=4.4e-5).

Conclusion

Using baseline data, we identified 6 putative novel RA subtypes which were associated with differences in MTX failure. Our study demonstrates the applicability of unsupervised deep learning and cluster analysis to elucidate hidden structure in the multi-modal EHR.

References

[1]Ronen J. doi:10.26508/lsa.201900517

[2]Levine JH. doi:10.1016/j.cell.2015.05.047

Disclosure of Interests

Tjardo Maarseveen: None declared, Marc Maurits: None declared, Thomas Huizinga: None declared, Marcel Reinders: None declared, Erik van den Akker: None declared, Rachel Knevel Grant/research support from: Rachel received a grant from Pfizer.

Immediate impact of COVID-19 on transplant activity in the Netherlands

The rapid emergence of the COVID-19 pandemic is unprecedented and poses an unparalleled obstacle in the sixty-five year history of organ transplantation. Worldwide, the delivery of transplant care is severely challenged by matters concerning - but not limited to - organ procurement, risk of SARS-CoV-2 transmission, screening strategies of donors and recipients, decisions to postpone or proceed with transplantation, the attributable risk of immunosuppression for COVID-19 and entrenched health care resources and capacity. The transplant community is faced with choosing a lesser of two evils: initiating immunosuppression and potentially accepting detrimental outcome when transplant recipients develop COVID-19 versus postponing transplantation and accepting associated waitlist mortality. Notably, prioritization of health care services for COVID-19 care raises concerns about allocation of resources to deliver care for transplant patients who might otherwise have excellent 1-year and 10-year survival rates. Children and young adults with end-stage organ disease in particular seem more disadvantaged by withholding transplantation because of capacity issues than from medical consequences of SARS-CoV-2. This report details the nationwide response of the Dutch transplant community to these issues and the immediate consequences for transplant activity. Worrisome, there was a significant decrease in organ donation numbers affecting all organ transplant services. In addition, there was a detrimental effect on transplantation numbers in children with end-organ failure. Ongoing efforts focus on mitigation of not only primary but also secondary harm of the pandemic and to find right definitions and momentum to restore the transplant programs.

FRI0585 HIGH-THROUGHPUT METHODOLOGY FOR EMR-BASED IDENTIFICATION OF CLINICAL SUB-PHENOTYPES IN COMPLEX PATIENT POPULATIONS

Background:

Heterogeneity in disease populations complicates discovery of risk factors. To identify risk factors for subpopulations of diseases, we need analytical methods that can deal with unidentified disease subgroups.

Objectives:

Inspired by successful approaches from the Big Data field, we developed a high-throughput approach to identify subpopulations within patients with heterogeneous, complex diseases using the wealth of information available in Electronic Medical Records (EMRs).

Methods:

We extracted longitudinal healthcare-interaction records coded by 1,853 PheCodes[1] of the 64,819 patients from the Boston’s Partners-Biobank. Through dimensionality reduction using t-SNE[2] we created a 2D embedding of 32,424 of these patients (set A). We then identified distinct clusters post-t-SNE using DBscan[3] and visualized the relative importance of individual PheCodes within them using specialized spectrographs. We replicated this procedure in the remaining 32,395 records (set B).

Results:

Summary statistics of both sets were comparable (Table 1).

Table 1.

Summary statistics of the total Partners Biobank dataset and the 2 partitions.

Set-Aset-BTotalEntries12,200,31112,177,13124,377,442Patients32,42432,39564,819Patientyears369,546.33368,597.92738,144.2unique ICD codes25,05624,95326,305unique Phecodes1,8511,8531,853

We found 284 clusters in set A and 295 in set B, of which 63.4% from set A could be mapped to a cluster in set B with a median (range) correlation of 0.24 (0.03 – 0.58).

Clusters represented similar yet distinct clinical phenotypes; e.g. patients diagnosed with “other headache syndrome” were separated into four distinct clusters characterized by migraines, neurofibromatosis, epilepsy or brain cancer, all resulting in patients presenting with headaches (Fig. 1 & 2). Though EMR databases tend to be noisy, our method was also able to differentiate misclassification from true cases; SLE patients with RA codes clustered separately from true RA cases.

Figure 1.

Two dimensional representation of Set A generated using dimensionality reduction (tSNE) and clustering (DBScan).

Figure 2.

Phenotype Spectrographs (PheSpecs) of four clusters characterized by “Other headache syndromes”, driven by codes relating to migraine, epilepsy, neurofibromatosis or brain cancer.

Conclusion:

We have shown that EMR data can be used to identify and visualize latent structure in patient categorizations, using an approach based on dimension reduction and clustering machine learning techniques. Our method can identify misclassified patients as well as separate patients with similar problems into subsets with different associated medical problems. Our approach adds a new and powerful tool to aid in the discovery of novel risk factors in complex, heterogeneous diseases.

References:

[1] Denny, J.C. et al. Bioinformatics (2010)

[2]van der Maaten et al. Journal of Machine Learning Research (2008)

[3] Ester, M. et al. Proceedings of the Second International Conference on Knowledge Discovery and Data Mining. (1996)

Disclosure of Interests:

Marc Maurits: None declared, Thomas Huizinga Grant/research support from: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Consultant of: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Marcel Reinders: None declared, Soumya Raychaudhuri: None declared, Elizabeth Karlson: None declared, Erik van den Akker: None declared, Rachel Knevel: None declared

Systemic features of retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations: a monogenic small vessel disease

BACKGROUND

Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is a small vessel disease caused by C-terminal truncating TREX1 mutations. The disease is typically characterized by vascular retinopathy and focal and global brain dysfunction. Systemic manifestations have also been reported but not yet systematically investigated.

METHODS

In a cross-sectional study, we compared the clinical characteristics of 33 TREX1 mutation carriers (MC+) from three Dutch RVCL-S families with those of 37 family members without TREX1 mutation (MC-). All participants were investigated using personal interviews, questionnaires, physical, neurological and neuropsychological examinations, blood and urine tests, and brain MRI.

RESULTS

In MC+, vascular retinopathy and Raynaud's phenomenon were the earliest symptoms presenting from age 20 onwards. Kidney disease became manifest from around age 35, followed by liver disease, anaemia, markers of inflammation and, in some MC+, migraine and subclinical hypothyroidism, all from age 40. Cerebral deficits usually started mildly around age 50, associated with white matter and intracerebral mass lesions, and becoming severe around age 60-65.

CONCLUSIONS

Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations is a rare, but likely underdiagnosed, systemic small vessel disease typically starting with vascular retinopathy, followed by multiple internal organ disease, progressive brain dysfunction, and ultimately premature death.

Presence of intragraft B cells during acute renal allograft rejection is accompanied by changes in peripheral blood B cell subsets

B cells have various functions, besides being plasma cell precursors. We determined the presence of intragraft B cells at time of acute rejection (AR) and looked for correlates of B cell involvement in peripheral blood. Renal biopsies at time of AR or stable graft function were analysed for the presence of B cells and B cell‐related gene expression, as well as C4d staining. Peripheral blood B cell subset distribution was analysed at various time‐points in patients with AR and controls, alongside serum human leucocyte antigen (HLA) antibodies. AR was accompanied by intragraft CD20⁺ B cells, as well as elevated CD20 (MS4A1) and CD19 gene expression compared to controls. B cell infiltrates were proportional to T cells, and accompanied by the chemokine pair C‐X‐C motif chemokine ligand 13 (CXCL13)–C‐X‐C motif chemokine receptor 5 (CXCR5) and B cell activating factor (BAFF). Peripheral blood memory B cells were decreased and naive B cells increased at AR, in contrast to controls. While 22% of patients with AR and 5% of controls showed de‐novo donor‐specific antibodies (DSA), all biopsies were C4d‐negative. These results suggest a role for B cells in AR by infiltrating the graft alongside T cells. We hypothesize that the shift in peripheral blood B cell composition is related to the graft infiltration at time of AR.

Is there long-term value of pathology scoring in immunoglobulin A nephropathy? A validation study of the Oxford Classification for IgA Nephropathy (VALIGA) update

Background

It is unknown whether renal pathology lesions in immunoglobulin A nephropathy (IgAN) correlate with renal outcomes over decades of follow-up.

Methods

In 1130 patients of the original Validation Study of the Oxford Classification for IgA Nephropathy (VALIGA) cohort, we studied the relationship between the MEST score (mesangial hypercellularity, M; endocapillary hypercellularity, E; segmental glomerulosclerosis, S; tubular atrophy/interstitial fibrosis, T), crescents (C) and other histological lesions with both a combined renal endpoint [50% estimated glomerular filtration rate (eGFR) loss or kidney failure] and the rate of eGFR decline over a follow-up period extending to 35 years [median 7 years (interquartile range 4.1–10.8)].

Results

In this extended analysis, M1, S1 and T1–T2 lesions as well as the whole MEST score were independently related with the combined endpoint (P &lt; 0.01), and there was no effect modification by age for these associations, suggesting that they may be valid in children and in adults as well. Only T lesions were associated with the rate of eGFR loss in the whole cohort, whereas C showed this association only in patients not treated with immunosuppression. In separate prognostic analyses, the whole set of pathology lesions provided a gain in discrimination power over the clinical variables alone, which was similar at 5 years (+2.0%) and for the whole follow-up (+1.8%). A similar benefit was observed for risk reclassification analyses (+2.7% and +2.4%).

Conclusion

Long-term follow-up analyses of the VALIGA cohort showed that the independent relationship between kidney biopsy findings and the risk of progression towards kidney failure in IgAN remains unchanged across all age groups and decades after the renal biopsy.

Early Conversion to Prednisolone/Everolimus as an Alternative Weaning Regimen Associates With Beneficial Renal Transplant Histology and Function: The Randomized-Controlled MECANO Trial

In renal transplantation, use of calcineurin inhibitors (CNIs) is associated with nephrotoxicity and immunosuppression with malignancies and infections. This trial aimed to minimize CNI exposure and total immunosuppression while maintaining efficacy. We performed a randomized controlled, open-label multicenter trial with early cyclosporine A (CsA) elimination. Patients started with basiliximab, prednisolone (P), mycophenolate sodium (MPS), and CsA. At 6 months, immunosuppression was tapered to P/CsA, P/MPS, or P/everolimus (EVL). Primary outcomes were renal fibrosis and inflammation. Secondary outcomes were estimated glomerular filtration rate (eGFR) and incidence of rejection at 24 months. The P/MPS arm was prematurely halted. The trial continued with P/CsA (N = 89) and P/EVL (N = 96). Interstitial fibrosis and inflammation were significantly decreased and the eGFR was significantly higher in the P/EVL arm. Cumulative rejection rates were 13% (P/EVL) and 19% (P/CsA), (p = 0.08). A post hoc analysis of HLA and donor-specific antibodies at 1 year after transplantation revealed no differences. An individualized immunosuppressive strategy of early CNI elimination to dual therapy with everolimus was associated with decreased allograft fibrosis, preserved allograft function, and good efficacy, but also with more serious adverse events and discontinuation. This can be a valuable alternative regimen in patients suffering from CNI toxicity.

Transplanting the elderly: Balancing aging with histocompatibility

Across the world, the proportions of senior citizens (i.e. those ≥65years) increase rapidly and are predicted to constitute over 25% of the general population by 2050. In 2012 already 48% of the population with end stage renal disease (ESRD) was aged 65years or older. Transplantation is considered the preferred treatment option for ESRD offering survival advantage over long-term dialysis in the majority of patients. Indeed, acceptable outcomes have been documented for selected patients over the age of 70years or even cases over 80years. The reality of organ scarcity and prolonged waiting times for a deceased donor kidney transplantation, however, indicate that at best 50% of the selected elderly may have realistic expectations to receive a timely transplant offer. By choice or medical selection, access to transplantation also decreases with increasing age. In order to expedite the chance for elderly to receive a kidney transplant dedicated allocation systems have been developed. These allocation systems, like the Eurotransplant Senior Program (ESP), support preferential local allocation of kidneys from older donors to older patients in order to match recipient and graft life while disregarding histocompatibility for HLA antigens. The consequence has been more acute rejection episodes and an increase in immunosuppressive load. In the elderly, the most common cause of graft loss is death with functioning graft and death from infectious diseases is one of the dominant causes. The Eurotransplant Senior DR-compatible Program (ESDP) was designed to further improve the perspective of successful transplantation in the elderly in terms of life and quality of life by re-introducing matching criteria for HLA-DR in the old-for-old algorithm.

Circulating microRNAs associate with diabetic nephropathy and systemic microvascular damage and normalize after simultaneous pancreas-kidney transplantation

Because microvascular disease is one of the most important drivers of diabetic complications, early monitoring of microvascular integrity may be of clinical value. By assessing profiles of circulating microRNAs (miRNAs), known regulators of microvascular pathophysiology, in healthy controls and diabetic nephropathy (DN) patients before and after simultaneous pancreas-kidney transplantation (SPK), we aimed to identify differentially expressed miRNAs that associate with microvascular impairment. Following a pilot study, we selected 13 candidate miRNAs and determined their circulating levels in DN (n = 21), SPK-patients (n = 37), healthy controls (n = 19), type 1 diabetes mellitus patients (n = 15) and DN patients with a kidney transplant (n = 15). For validation of selected miRNAs, 14 DN patients were studied longitudinally up to 12 months after SPK. We demonstrated a direct association of miR-25, -27a, -126, -130b, -132, -152, -181a, -223, -320, -326, -340, -574-3p and -660 with DN. Of those, miR-25, -27a, -130b, -132, -152, -320, -326, -340, -574-3p and -660 normalized after SPK. Importantly, circulating levels of some of these miRNAs tightly associate with microvascular impairment as they relate to aberrant capillary tortuosity, angiopoietin-2/angiopoietin-1 ratios, circulating levels of soluble-thrombomodulin and insulin-like growth factor. Taken together, circulating miRNA profiles associate with DN and systemic microvascular damage, and might serve to identify individuals at risk of experiencing microvascular complications, as well as give insight into underlying pathologies.

Microvascular damage in type 1 diabetic patients is reversed in the first year after simultaneous pancreas-kidney transplantation

Simultaneous pancreas-kidney transplantation (SPK) is an advanced treatment option for type 1 diabetes mellitus (DM) patients with microvascular disease including nephropathy. Sidestreamdarkfield (SDF) imaging has emerged as a noninvasive tool to visualize the human microcirculation. This study assessed the effect of SPK in diabetic nephropathy (DN) patients on microvascular alterations using SDF and correlated this with markers for endothelial dysfunction. Microvascular morphology was visualized using SDF of the oral mucosa in DN (n = 26) and SPK patients (n = 38), healthy controls (n = 20), DM1 patients (n = 15, DM ≥ 40 mL/min) and DN patients with a kidney transplant (KTx, n = 15). Furthermore, 21 DN patients were studied longitudinally up to 12 months after SPK. Circulating levels of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and soluble thrombomodulin (sTM) were measured using ELISA. Capillary tortuosity in the DN (1.83 ± 0.42) and DM ≥ 40 mL/min (1.55 ± 0.1) group was increased and showed reversal after SPK (1.31 ± 0.3, p < 0.001), but not after KTx (1.64 ± 0.1). sTM levels were increased in DN patients and reduced in SPK and KTx recipients (p < 0.05), while the Ang-2/Ang-1 ratio was normalized after SPK and not after KTx alone (from 0.16 ± 0.04 to 0.08 ± 0.02, p < 0.05). Interestingly, in the longitudinal study, reversal of capillary tortuosity and decrease in Ang-2/Ang-1 ratio and sTM was observed within 12 months after SPK. SPK is effective in reversing the systemic microvascular structural abnormalities in DN patients in the first year after transplantation.

Concentration-controlled treatment of lupus nephritis with mycophenolate mofetil

Background:

Mycophenolate mofetil (MMF) has recently been established as a potent drug in maintenance treatment for lupus nephritis. However, there is no consensus on the optimal dosing regimen because of a high inter-individual variability of mycophenolic acid (MPA), the active metabolite of MMF. This retrospective study aimed to investigate the effect of an individualized dosing regimen through concentration-controlled treatment on MPA exposure and renal outcome in patients with lupus nephritis.

Methods:

Sixteen patients with lupus nephritis and treatment with low-dose intravenous cyclophosphamide followed by MMF were included. MPA area under the plasma concentration-time curve from 0 to 12 hours (MPA-AUC0–12) was assessed within a month after MMF initiation. After determination of MPA-AUC0–12, MMF doses were titrated to achieve a target MPA-AUC0–12 of 60–90 mg*h/l. After on average six months, MPA-AUC0–12 measures were repeated to assess the effect of dose adjustment.

Results:

One month after introducing MMF, MPA-AUC0–12 was low and showed a high inter-individual variability. Dose adjustment with a target MPA-AUC0–12 of 60–90 mg*h/l resulted in individualized MMF dosing, significantly higher MPA-AUC0–12 levels, and a non-significant reduction in variability of MPA-AUC0–12. Adverse effects were reported by 37.5% of patients, which resulted in a switch to azathioprine in two patients. There was no significant relationship between the occurrence of adverse effects and MPA-AUC0–12. At 12 months of follow-up 87.5% of patients had achieved either partial (18.7%) or complete (68.8%) remission.

Conclusion:

Concentration-controlled dose adjustments with a target MPA-AUC0–12 of 60–90 mg*h/l was associated with optimized MPA exposure and an excellent renal outcome at 12 months of follow-up in a small sample of SLE patients with lupus nephritis.

Donor brain death predisposes human kidney grafts to a proinflammatory reaction after transplantation

Donor brain death has profound effects on post-transplantation graft function and survival. We hypothesized that changes initiated in the donor influence the graft's response to ischemia and reperfusion. In this study, human brain dead donor kidney grafts were compared to living and cardiac dead donor kidney grafts. Pretransplant biopsies of brain dead donor kidneys contained notably more infiltrating T lymphocytes and macrophages. To assess whether the different donor conditions result in a different response to reperfusion, local cytokine release from the reperfused kidney was studied by measurement of paired arterial and renal venous blood samples. Reperfusion of kidneys from brain dead donors was associated with the instantaneous release of inflammatory cytokines, such as G-CSF, IL-6, IL-9, IL-16 and MCP-1. In contrast, kidneys from living and cardiac dead donors showed a more modest cytokine response with release of IL-6 and small amounts of MCP-1. In conclusion, this study shows that donor brain death initiates an inflammatory state of the graft with T lymphocyte and macrophage infiltration and massive inflammatory cytokine release upon reperfusion. These observations suggest that brain dead donors require a novel approach for donor pretreatment aimed at preventing this inflammatory response to increase graft survival.

Preoperative biliary drainage, colonisation of bile and postoperative complications in patients with tumours of the pancreatic head: a retrospective analysis of 241 consecutive patients

OBJECTIVE

To analyse the outcome of preoperative biliary drainage in patients being operated on for a tumour in the pancreatic head.

DESIGN

Retrospective study.

SETTING

University hospital, The Netherlands.

SUBJECTS

Consecutive series of 241 patients.

MAIN OUTCOME MEASURES

Decline in bilirubin concentrations and bacterial contamination of bile as a result of preoperative drainage. Incidence of postoperative complications in patients who underwent preoperative drainage and those who did not.

RESULTS

184/241 patients underwent preoperative biliary drainage. Endoscopic drainage was the most effective, shown by a median reduction in bilirubin concentrations of 82%, 74%, and 50% after endoscopic drainage (n = 149), papillotomy (n = 25) and external drainage (n = 10), respectively. Bacterial contamination of bile was significantly more common when an endoprosthesis was used, but did not result in a higher rate of infective complications. 163 Whipple's resections, 33 total pancreatectomies, and 45 biliary-enteric bypasses were performed. 137/241 (57%) patients had postoperative complications. There was no significant difference in the incidence of postoperative complications between patients who had preoperative biliary drainage and those who did not (p = 0.4).

Which advance directive do patients prefer?

This study examined patient acceptance of two different advance directives. Outpatients completed the two directives and a 12-item acceptability questionnaire for each, and then stated their directive preferences. Of 128 patients enrolled, 97 (76%) responded. Overall, 47% of the respondents were satisfied with the Let Me Decide directive and 53% with the Medical Directive (NS). Thirty-nine percent preferred the Let Me Decide directive, 37% preferred the Medical Directive, and 25% had no preference or were uncertain which they preferred. Although there was no difference in patient acceptance between the directives, 76% of the patients preferred one or the other. Therefore, different people like different directives, and a variety of directives should be available for patients to review before they complete one.

Hypnotherapy and contractures of the hand

Contractures of the hand are rather uncommon conversion phenomena. As yet, very little is known about treatment. After a brief overview of the literature on the various treatment strategies, we describe the treatment of four patients. There are indications that a complaint-centered approach, which attempts to influence the symptom directly, produces positive results. Hypnotherapeutic techniques were used in the four patients described here. Treatment resulted in improvement in three of the four.

The sequence of the nucleocapsid protein (N) gene of Piry virus: possible domains in the N protein of vesiculoviruses

A number of independent cDNA clones of the Piry virus N gene message were identified and sequenced. From the resulting sequences and previously published data, we derived the sequence of the mRNA for this protein. Sequence similarities of the translated region of Piry virus with that of other viruses suggest that Piry virus is as distantly related to Chandipura virus as it is to the vesicular stomatitis viruses of Indiana and New Jersey serotypes. Based on the relative conservation of the amino acid sequence of the nucleocapsid protein of these vesiculoviruses, the N protein can be subdivided into at least three regions, possibly indicative of functional domains.