[Interdisciplinary ultrasound-guided, minimally invasive autopsy in COVID-19-deceased patients in the intensive care unit of a university hospital : A proof-of-concept study]. / Interdisziplinäre ultraschallgesteuerte minimal-invasive Autopsie bei COVID-19-Verstorbenen auf der Intensivstation einer Universitätsklinik : Eine Proof-of-Concept-Studie.

In this feasibility study, we carried out in an interdisciplinary team standardised, ultrasound-guided, minimally invasive autopsy (US-MIA) directly at the bedside of patients who died of COVID-19 in the intensive care unit of the Rechts der Isar Hospital of the Technical University Munich (TUM). The aim of the study was to verify the feasibility, time efficiency and infection hygiene aspects of the process, as well as the quality of the tissue samples. Our results show that bedside US-MIA is suitable for obtaining tissue samples before the onset of postmortem autolysis, and that it can also be carried out quickly and safely. The potential of US-MIA, which has gained little recognition so far, deserves special attention in the context of postmortem diagnosis, research and quality assurance. In the future, these strengths of US-MIA could help to lead postmortem diagnosis into the modern age of pathological deep analytics ("omics").

[Innovations in peritoneal dialysis]. / Innovationen in der Peritonealdialyse.

Peritoneal dialysis used to be a common treatment for acute kidney failure that required dialysis. In favor of continuous, extracorporeal renal replacement procedures, it disappeared from the scene in the western world, whereas it continues to be used in structurally poor countries due to its simplicity and low resource intensity. Recently, the shortages in medical care in the context of the coronavirus disease 2019 (COVID-19) pandemic led to renewed worldwide interest in peritoneal dialysis as a safe option in acute kidney failure requiring dialysis. The introduction of biocompatible solutions 20 years ago was expected to reduce mortality or technical failure. Unfortunately, so far this could only be implied but not confirmed in studies. Immunomodulatory adjuvants are an innovative option which have the potential to improve the local immunocompetence and prevent the loss of peritoneal function. Currently, the vision of a wearable artificial kidney is getting closer. Intensification of dialysis dose also appears achievable with minimal dialysate volumes. In times of global warming, the regeneration of dialysates could not only save relevant amounts of water but also have a favorable impact on the CO2 balance. In summary, peritoneal dialysis is currently enjoying a comeback. This article describes the current and future developments of this procedure.

[Prospective monitoring of a university rheumatology outpatient clinic throughout the first wave of the COVID-19 pandemic : What lessons can be learned?] / Prospektive Verlaufsbeobachtung einer universitären Rheumaambulanzkohorte während der ersten Welle der COVID-19-Pandemie : Welche Lehren kann man ziehen?

BACKGROUND: In March 2020 the SARS-CoV­2 pandemic disseminated initially especially in Bavaria. At that time data on patients with rheumatic diseases and immunomodulatory treatment was lacking. OBJECTIVE: The aim was to analyze the influence of the SARS-CoV­2 pandemic on the clinical treatment strategy. MATERIAL AND METHODS: Between 16 March and 31 July 2020 all patients who consecutively presented at the rheumatology outpatient clinic of the Klinikum rechts der Isar of the Technical University of Munich were included in the study. Individual treatment adjustments were based on clinical judgment and the recommendations for action of the German Society for Rheumatology (DGRh). RESULTS: A total of 322 patients were included. The most frequent diagnosis was rheumatoid arthritis with 17%, ANCA-associated vasculitis (AAV) with 14% and SLE with 12%. Of the patients 262 were on DMARD treatment and 77 received oral glucocorticoids. There were 5 cases of suspected SARS-CoV­2 infection; however, no patient verifiably became ill due to COVID-19. In 40 patients, treatment adjustments were done due to the pandemic, whereby 3 patients developed a flare of the underlying disease. In retrospect, treatment de-escalation occurred most frequently in AAV, IgG4-related disease, immunosuppressive treatment with rituximab and the simultaneous presence of malignant diseases. CONCLUSION: The total lack of confirmed SARS-CoV­2 infections in an otherwise strongly affected region could indicate that the infection risk for SARS-CoV­2 is not substantially increased for patients with inflammatory rheumatic diseases. A continuation of most immunosuppressive medications therefore seems reasonable during the ongoing pandemic.

Adult macrophage activation syndrome-haemophagocytic lymphohistiocytosis: 'of plasma exchange and immunosuppressive escalation strategies' - a single centre reflection.

OBJECTIVE: In the context of systemic autoimmunity, that is systemic lupus erythematosus (SLE) or adult-onset Still's disease (AOSD), secondary haemophagocytic lymphohistiocytosis (HLH; also referred to as macrophage activation syndrome (MAS) or more recently MAS-HLH) is a rare and potentially life-threatening complication. Pathophysiological hallmarks are aberrant macrophage and T cell hyperactivation and a systemic cytokine flare, which generate a sepsis-like, tissue-damaging, cytopenic phenotype. Unfortunately, for adult MAS-HLH we lack standardized treatment protocols that go beyond high-dose corticosteroids. Consequently, outcome data are scarce on steroid refractory cases. Aside from protocols based on treatment with calcineurin inhibitors, etoposide, cyclophosphamide and anti-IL-1, favourable outcomes have been reported with the use of intravenous immunoglobulin (IvIG) and plasma exchange (PE). METHODS: Here we report a retrospective series of steroid refractory MAS-HLH, the associated therapeutic regimes and outcomes. RESULTS: In this single-centre experience, 6/8 steroid refractory patients survived (median follow-up: 54.4 (interquartile range: 23.3-113.3) weeks). All were initially treated with PE, which induced partial response in 5/8 patients. Yet, all patients required escalation of immunosuppressive therapies. One case of MAS-HLH in new-onset AOSD had to be escalated to etoposide, whereas most SLE-associated MAS-HLH patients responded well to cyclophosphamide. Relapses occurred in 2/8 cases. CONCLUSION: Together, early use of PE is at most a supportive measure, not a promising monotherapy of adult MAS-HLH. In refractory cases, conventional cytoreductive therapies (i.e. cyclophosphamide and etoposide) constitute potent and reliable rescue approaches, whereas IvIG, anti-thymoglobulin, and biologic agents appear to be less effective.

European Renal Best Practice Guideline on kidney donor and recipient evaluation and perioperative care

The European Best Practice Guideline group (EBPG) issued guidelines on the evaluation and selection of kidney donor and kidney transplant candidates, as well as post-transplant recipient care, in the year 2000 and 2002. The new European Renal Best Practice board decided in 2009 that these guidelines needed updating. In order to avoid duplication of efforts with kidney disease improving global outcomes, which published in 2009 clinical practice guidelines on the post-transplant care of kidney transplant recipients, we did not address these issues in the present guidelines.The guideline was developed following a rigorous methodological approach: (i) identification of clinical questions, (ii) prioritization of questions, (iii) systematic literature review and critical appraisal of available evidence and (iv) formulation of recommendations and grading according to Grades of Recommendation Assessment, Development, and Evaluation (GRADE). The strength of each recommendation is rated 1 or 2, with 1 being a 'We recommend' statement, and 2 being a 'We suggest' statement. In addition, each statement is assigned an overall grade for the quality of evidence: A (high), B (moderate), C (low) or D (very low). The guideline makes recommendations for the evaluation of the kidney transplant candidate as well as the potential deceased and living donor, the immunological work-up of kidney donors and recipients and perioperative recipient care.All together, the work group issued 112 statements. There were 51 (45%) recommendations graded '1', 18 (16%) were graded '2' and 43 (38%) statements were not graded. There were 0 (0%) recommendations graded '1A', 15 (13%) were '1B', 19 (17%) '1C' and 17 (15%) '1D'. None (0%) were graded '2A', 1 (0.9%) was '2B', 8 (7%) were '2C' and 9 (8%) '2D'. Limitations of the evidence, especially the lack of definitive clinical outcome trials, are discussed and suggestions are provided for future research.We present here the complete recommendations about the evaluation of the kidney transplant candidate as well as the potential deceased and living donor, the immunological work-up of kidney donors and recipients and the perioperative recipient care. We hope that this document will help caregivers to improve the quality of care they deliver to patients. The full version with methods, rationale and references is published in Nephrol Dial Transplant (2013) 28: i1-i71; doi: 10.1093/ndt/gft218 and can be downloaded freely from http://www.oxfordjournals.org/our_journals/ndt/era_edta.html.

Single-dose rituximab for remission induction and maintenance therapy in ANCA-associated vasculitis: a retrospective analysis of 17 patients.

OBJECTIVES: The aim of this study was to evaluate the efficacy of a repeated single-dose rituximab (RTX) regimen for remission induction and maintenance in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHOD: We performed a retrospective analysis of all patients with an established diagnosis of AAV who were treated with single-dose RTX infusions at our institution. Clinical outcome data were assessed over a period of 24 months. RESULTS: Sixteen patients were treated for remission induction and maintenance and one patient was treated for only maintenance therapy. Remission (absence of disease activity during the past 3 months and a prednisolone dose of ≤ 7.5 mg) was achieved in 11 patients (68%) with a mean time to remission of 9.4 (range 3-24) months. At 6 months, six patients (37.5%) were in remission and the mean prednisolone dose of all responding patients was 8.2 mg. Five patients had treatment failure due to early relapsing (n = 4) or persistently active (n = 1) disease. At 24 months, nine of the 11 responding patients (82%) were in remission. All patients still had concomitant steroid and/or disease-modifying anti-rheumatic drug (DMARD) therapy at 24 months. Overall, 11 relapses were seen in nine patients (five non-responders and four responders) with a mean time to relapse of 5.3 (range 4-24) months. No major relapses were observed in the responding patients. Severe infections were only seen in patients who had been previously treated with cyclophosphamide (CYC). CONCLUSIONS: The combination of single-dose RTX with other immunosuppressants seems less effective than the standard RTX regimen for the induction of remission of AAV.

Identification and characterization of a defective CYP3A4 genotype in a kidney transplant patient with severely diminished tacrolimus clearance.

Cytochrome P450 3A4 (CYP3A4) is a major drug-metabolizing enzyme that is widely investigated. So far, no homozygous inactive variant has been described. We report on a 19-year-old kidney transplant patient suffering from Alport syndrome, who experienced unexpected high tacrolimus plasma trough levels during immunosuppressant therapy. Because nonadherence, liver failure, or drug-drug interactions could be excluded, we hypothesized a diminished metabolism of the drug caused by mutations in the main detoxification enzyme, CYP3A4. Exome sequencing revealed a novel single-nucleotide polymorphism (c.802C>T) resulting in a premature stop codon in CYP3A4 exon 5. Accordingly, no CYP3A4 protein could be detected in kidney biopsy tissue, and there was lack of expression in HepG2 cells transiently transfected with the mutated CYP3A4. In addition, the patient harbored inactive CYP3A5*3, resulting in loss of function of the entire CYP3A locus, explaining the deteriorated tacrolimus clearance. This is, to our knowledge, the first case of a complete failure of CYP3A4 in humans.

Dexamethasone protects from renal ischemia/reperfusion injury: a possible association with SGK-1.

Previous experimental data suggest that steroids might have protective effects during hypoxic/ischemic injury of various organs. In this study, the association between dexamethason (Dexa) treatment and the anti-apoptotic SGK-1 was tested in ischemic renal injury. In vitro, HK-2 cells were exposed to 24 h hypoxia, and the effect of Dexa incubation on SGK-1 expression / activation and on cell death was studied. In an in vivo rat model of unilateral renal IR, animals were treated with Dexa, and serum renal function parameters, tissue injury and SGK-1 expression and localization were examined after different reperfusion times (2 h, 4 h and 24 h). Dexa at a dose of 2 mg/L exerted a protective effect on cell survival assessed by LDH release and vital staining paralleled by marked up-regulation of SGK-1. In rats, 2 mg/kg Dexa treatment 24 h prior to ischemia resulted in less severe tissue injury and ameliorated urea nitrogen levels 24 h after reperfusion. Furthermore, SGK-1 expression and phosphorylation were higher in Dexa animals demonstrated by Western blot and immunofluorescence technique. Our results provide novel data on the signalling mechanism of Dexa under hypoxia / ischemia and further support that Dexa emerges as an attractive pharmacological agent for the prevention of ischemic injury.

High dose human insulin and insulin glargine promote T24 bladder cancer cell proliferation via PI3K-independent activation of Akt.

BACKGROUND: This study was to investigate the effects of human insulin and insulin glargine on proliferation of T24 human bladder cancer cells and the implication of the PI3K/Akt and MEK/ERK1/2 pathways. METHODS: After exposure to insulin or glargine at the indicated concentrations for certain time courses, in the absence or presence of inhibitor for MEK (PD98059) or PI3K (LY294002), T24 cell proliferation was evaluated by CCK-8 assay. Phosphorylation of Akt and ERK1/2 was analyzed by Western blot. RESULTS: Insulin and glargine similarly induced phosphorylation of Akt and slight increases in T24 cell proliferation at 10-100IU/L. LY294002 remarkably reduced T24 cell proliferation in all groups. However, in the presence of LY294002, cell growth was still promoted by insulin and glargine relative to LY294002-treated group. Accordingly, LY294002 profoundly reduced protein levels of pAkt, while insulin and glargine increased pAkt in T24 cells pretreated with LY294002 as compared with cells treated with LY294002 alone. PD98059 reduced pERK while enhanced T24 cell proliferation. Insulin and glargine increased pERK at 15, 30, 60 min, not at 24h. CONCLUSIONS: High dose human insulin and insulin glargine similarly promoted T24 bladder cancer cell proliferation via PI3K-independent activation of Akt.

ARFI-based tissue elasticity quantification and kidney graft dysfunction: first clinical experiences.

BACKGROUND AND PURPOSE: Beyond the medical history, the clinical exam and lab findings, non-invasive ultrasound parameters such as kidney size and Doppler values (e.g. the resistive index) are important tools assisting clinical decision making in the monitoring of renal allografts. The gold standard for the diagnosis of renal allograft dysfunction remains the renal biopsy; while an invasive procedure, the justifiable necessity for this derives from its definitive nature a requirement beyond the synopses of all non-invasive tools. "Acoustic Radiation Force Impulse Imaging"(ARFI)-quantification is a novel ultrasound-based technology measuring tissue elasticity properties. So far experience related to this new method has not been reported in renal transplant follow-up. The purpose of this study was to evaluate changes in ARFI-measurements between clinically stable renal allografts and biopsy-proven transplant dysfunction. METHODS: We employed "Virtual Touch™ tissue quantification" (Siemens Acuson, S2000) for the quantitative measurement of tissue stiffness in the cortex of transplant kidneys. We performed initial baseline and later disease-evaluative ultrasound examinations in 8 renal transplant patients in a prospective study design. Patients were first examined during stable allograft function with a routine post-transplant renal ultrasound protocol. A second follow-up examination was carried out on subsequent presentation with transplant dysfunction prior to allograft biopsy and histological evaluation. All patiens were examined using ARFI-quantification (15 measurements/kidney). Resistive indices (RI) were calculated using pulsed-wave Doppler ultrasound, and transplant kidney size was measured on B-mode ultrasound images. All biopsies were evaluated histologically by a reference nephropathologist unaware of the results of the ultrasound studies. Histopathological diagnoses were based on biopsy results, taking clinical and laboratory findings into account. Finally we calculated the relative changes in ARFI-quantification, resistive indices and the absolute change of kidney size on a percentage basis at these defined assessment times and compared the results with the final pathologic diagnosis. RESULTS: Histological results enumerated five cases of acute T-cell-mediated rejection, one case of calcineurin inhibitor toxicity and two cases of acute tubular necrosis. Calcineurin inhibitor toxicity and acute tubular necrosis were subsumed as "other pathologies". Mean ARFI-values showed an average increase of more than 15% percent in transplants with histologically proven acute rejection whereas no increase was seen in transplants with other pathologies. Mean RI-values showed no increase either in the diagnostic group of acute rejection, nor in the group with other pathologies. Kidney size showed a mean absolute increase of 0.5 centimetres in allografts with acute rejection, whereas a mean decrease of 0.17 centimetres was seen in the group with other pathologies. CONCLUSION: As shown before in other studies, RI values and kidney size are of doubtful utility in the evaluation of kidney allograft dysfunction. ARFI-based elasticity measurement shows promise as a complementary non-invasive parameter in follow-on diagnosis of renal allograft rejection.

ARFI-based tissue elasticity quantification in comparison to histology for the diagnosis of renal transplant fibrosis.

BACKGROUND AND PURPOSE: Until recently clinical diagnosis of chronic renal allograft dysfunction could only be established invasively by renal biopsy. Given the risks of that procedure, a non-invasive, diagnostic test would be very advantageous. Novel ultrasound-based elasticity tools, using "Acoustic Radiation Force Impulse (ARFI)" technology are now available. Previously this technique has been utilised to quantify liver fibrosis. First results of these studies are promising. The purpose of our study was to investigate correlation between stiffness values obtained by ARFI-quantification and histological fibrosis score in renal transplants. METHODS: We employed "Virtual Touch™ tissue quantification" (Siemens Acuson, S2000) to quantitatively measure tissue stiffness in the cortex of transplant kidneys. Eighteen patients were included in this prospective study, recording close temporal ARFI-quantification and fibrosis measurements. All patients undergoing renal transplant biopsy were examined with ARFI-quantification (15 measurements per transplant kidney). Resistive indices were also calculated from pulsed-wave Doppler ultrasound. Transplant biopsies were histologically evaluated by a reference nephropathologist and graded according to the percentage of fibrosis and to the BANFF-score. Due to the non-normal distribution of the data the Spearman-correlation-coefficient (rho) was used to assess the bivariate relationship of ARFI and fibrosis in the transplant kidney. RESULTS: There was a significant positive moderate correlation between mean ARFI-values and the grade of fibrosis (rho = +0.465; p = 0.026). This correlation was also valid for the mean ARFI-values and the BANFF-category (rho = +0.468; p = 0.025). There was no significant correlation between the mean ARFI-values and the resistive indices in the transplant kidney (rho = +0.034; p = 0.904). Nevertheless, a positive correlation between the mean RI-values of the kidney and the grade of fibrosis was established (rho = +0.563; p = 0.015). CONCLUSION: The mean values of ARFI measurements and the resistive indices are potentially independent explanation variables for evaluating the grade of fibrosis in transplant kidneys.

TRAF6 knockdown promotes survival and inhibits inflammatory response to lipopolysaccharides in rat primary renal proximal tubule cells.

AIM: TRAF6 is a unique adaptor protein of the tumour necrosis factor receptor-associated factor family that mediates both tumour necrosis factor receptor (TNFR) and interleukin-1 receptor/Toll-like receptor (IL-1R/TLR) signalling. Activation of IL-1R/TLR and TNFR pathways in renal tubular cells contributes to renal injury. This study aimed to investigate if blockade of lipopolysaccharide (LPS)-triggered TLR4 signalling by small interfering RNA (siRNA) targeting TRAF6 protects survival and inhibits inflammatory response in isolated rat renal proximal tubular cells (PTCs). METHODS: PTCs isolated from F344 rat kidneys were transfected with chemically synthesized siRNA targeting TRAF6 mRNA. Real-time quantitative PCR was applied to measure mRNA level of TRAF6, TNF-alpha, IL-6 and monocyte chemoattractant protein-1 (MCP-1). Protein levels of extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase, caspase 3 and cleaved caspase 3 were evaluated by Western blotting. Cell viability was analysed with XTT reagents. RESULTS: We found that the TRAF6 gene was effectively silenced in PTCs using siRNA. TRAF6 knockdown resulted in reduced TNF-alpha and IL-6 mRNA expression upon LPS challenge. LPS-induced phosphorylation of JNK and p38 was attenuated in TRAF6 siRNA-transfected cells while the change in the phosphorylation of ERK was not remarkable. TRAF6 knockdown was associated with increased cell viability and reduced protein level of cleaved caspase-3, both, in the absence and presence of LPS. CONCLUSION: Our studies suggest that TRAF6 knockdown may inhibit inflammatory response and promote cell survival upon LPS challenge in primary rat proximal renal tubular cells.

Interrelationship between aortic stiffness and proteinuria in chronic kidney disease.

Aortic stiffness and proteinuria are cardiovascular risk factors that are generally associated with each other. We analysed whether this is true for patients with chronic kidney disease (CKD). We hypothesized that in CKD patients of young age and predominant sole renal disease, aortic stiffness has no predictive value for proteinuria. In a cross-sectional setting, 144 patients with severe-to-mild CKD (estimated glomerular filtration rate (eGFR) 0 to <90 ml min(-1) 1.73 m(-2)) were analysed for stiffness, as measured using carotid-femoral pulse wave velocity (C-F PWV), and proteinuria, as determined using protein-creatinine ratio from morning spot urine. In stepwise linear regression analysis, C-F PWV predicted protein-creatinine ratio and vice versa. Younger patients (<50 years) with proteinuria had predominant glomerulonephritis. These were characterized by lower C-F PWV despite similar renal function when compared with younger patients without glomerulonephritis. We conclude that in CKD patients a general relationship exists between aortic stiffness and proteinuria. It is noted that this relation is lost in young CKD patients with predominant sole renal disease. In this study, C-F PWV is not predictive for proteinuria as renal disease is the leading cause of proteinuria.

Lupus nephritis reoccurs following transplantation in the lupus prone mouse.

The incidence and pathomechanism of recurrent lupus nephritis (RLN) after transplantation is not clearly understood. Burning out of the autoimmune process or local immunoregulatory mechanisms in the kidney may be responsible for the low incidence of recurrence. These mechanisms cannot be investigated in human subjects, due to post-transplant immunosuppression. To investigate the pathomechanisms of RLN, male and female kidneys were transplanted from FAS deficient lupus prone (LPR) or control (FAS intact) MRL mice into either LPR or MRL recipients. Urinary protein and blood urea were assessed. Double negative (DN) lymphocyte proliferation was determined by flow cytometry. Two months after transplantation inflammatory infiltration of the glomerular, vascular and interstitial compartments were determined. Renal function as demonstrated by blood urea levels was normal in MRL recipients, but elevated in LPR recipients, independent of the donor strain. Paralleling functional results, inflammatory infiltration was mild or absent in MRL recipients of MRL grafts, and mild to moderate in MRL recipients of LPR grafts, suggesting that kidney removal from the autoimmune (LPR) environment significantly reduced inflammation. Graft infiltration was most severe in LPR recipients: grafts were similarly inflamed independent of the donor. All LPR recipients had significantly less CD4+ Th cells versus MRL mice. Transplantation of LPR grafts into MRL recipients reduced CD4+ Th cell percentage, accompanied by a slight induction of lupus autoantibody production. Our results demonstrate that lupus nephritis is not kidney specific in the LPR model with recurrence after transplantation in the absence of immunosuppression.

Urinary L-FABP and anaemia: distinct roles of urinary markers in type 2 diabetes.

BACKGROUND: Urinary liver-type fatty acid binding protein (L-FABP) and kidney injury molecule (KIM)-1, novel urinary biomarkers of renal tubulointerstitial function, have previously been associated with acute ischaemic kidney injury. We studied the clinical significance of urinary L-FABP, KIM-1 and N-acetyl-beta-glucosaminidase (NAG) as potential markers of renal function and chronic ischaemic injury in patients with diabetic nephropathy. MATERIAL AND METHODS: A total of 130 type 2 diabetes patients with early diabetic nephropathy and 40 healthy controls were studied. Urinary L-FABP, KIM-1, NAG, albumin excretion rate (AER) and creatinine clearance were obtained from 24-h urine samples, and correlated with measures of red blood cell count, renal function and metabolic control. RESULTS: Urinary L-FABP was significantly increased in diabetes patients compared with healthy controls [8.1 (interquartile 0.6-11.6) vs. 2.4 (0.5-3.6) microg/g creatinine, P < 0.001] and correlated with AER (r = 0.276, P = 0.002), creatinine clearance (r = -0.189, P = 0.033) and haemoglobin levels (r = -0.190, P = 0.030). In multivariable linear regression analysis, haemoglobin (beta = -0.247, P = 0.015) and AER (beta = 0.198, P = 0.046) were significant predictors of urinary L-FABP. Prevalent anaemia was independently associated with a 6-fold risk for increased tubulointerstitial kidney damage (upper vs. lower two L-FABP tertiles: OR, 6.06; 95% CI: 1.65-22.23; P = 0.007). Urinary KIM-1 was not significantly associated with kidney function, AER, or measures of red blood cell count while urinary NAG was associated with parameters of glucose control and renal function. CONCLUSIONS: Different urinary biomarkers may reflect distinct pathophysiological mechanisms of tubulointerstitial damage in early diabetic nephropathy: Urinary L-FABP could be a novel biomarker for chronic intrarenal ischaemia.

Fisher-Lewis kidney transplantation model as a tool for investigation of transplantation-induced cardiomyopathy.

BACKGROUND: Cardiovascular disease is a major cause of death after kidney transplantation; thus, cardiovascular protection is a major concern in transplant recipients. Data about cardiac characteristics from animal models after kidney transplantation are lacking. Therefore, we investigated cardiac structure and function in a model of chronic allograft injury. METHODS: Kidneys from Fisher 344 rats were orthotopically transplanted into Lewis rats. Eight recipient rats were treated with placebo or an angiotensin II type-1 receptor blocker (AT1RB; candesartan cilexitil, 5 mg/kg/d) for 24 weeks posttransplantation, and 8 untreated matched Lewis rats were used as healthy controls. Echocardiography was performed at 24 weeks posttransplantation to measure ejection fraction, fractional shortening, and left ventricular mass, in triplicate. Proteinuria at 24 hours was determined, and after harvesting, the heart weight-body weight ratio (HW/BW) was measured. RESULTS: At 24 weeks posttransplantation, renal transplant-recipient rats demonstrated a significantly decreased ejection fraction (mean [SD], 58.9% [3.2%] vs 70.7% [2.1%]) and fractional shortening (29.8% [2.0%] vs 38.3% [2.0%]) and increased HW/BW and left ventricular mass (7.7 [0.2] cm(3) vs 6.7 [0.2] cm(3)) compared with healthy control rats. The HW/BW and left ventricular mass were significantly ameliorated by AT1RB compared with placebo-treated transplant-recipient rats (6.8 [0.2] cm(3) vs 7.7 [0.2] cm(3)). In addition, decreased proteinuria was evident after AT1RB. CONCLUSION: The Fisher-Lewis rat kidney transplantation model resulted in cardiac hypertrophy and decreased cardiac function. AT1RB normalized cardiac hypertrophy without improving function. These findings demonstrate that the Fisher-Lewis rat renal transplantation model can be used to investigate transplantation-induced cardiomyopathy.

Evaluation of Acoustic Radiation Force Impulse (ARFI) imaging and contrast-enhanced ultrasound in renal tumors of unknown etiology in comparison to histological findings.

PURPOSE: It was the aim of our study to combine the findings of contrast-enhanced ultrasound and ARFI-imaging in the evaluation of renal masses in comparison to the histological findings. MATERIALS AND METHODS: Fifteen patients with unclear kidney lesions were analyzed. We used a high-end ultrasound machine (Siemens ACUSON S2000, Siemens Healthcare, Erlangen, Germany) with a multifrequency curved array 4 MHz or linear 9 MHz transducer. Contrast-enhanced ultrasound (bolus injection 1.6-2.4 ml SonoVue was carried out. We obtained fifteen ARFI measurements from each patient with at least five values for quantification. The ARFI-ROI (region of interest) was placed in the ventral margin of the kidney tumor and the whole ROI was covered by the tumor. The "reference-ROI" was placed in the ventral kidney parenchyma of the patient at a distance of at least two centimeters from the tumor. All renal tumors were surgically resected. In cases of complex renal cysts or anatomic variations mimicking renal tumors ("pseudo-tumors"), constant results of ultrasound examinations and additional MRI or multiphase CT over 6 months were required. RESULTS: Fifteen patients were included in the study and were examined using the diagnostic ultrasound tools of our study The kidney tumors of our patients had diameters ranging from 1.5 to 8 cm and were located at depths ranging from 2 to 5.5 cm. ARFI imaging was also performed in all patients. A field up to a depth of 10 cm could be visualized for diagnostic use. Performing ARFI quantification using Siemens Virtual Touch Tissue Quantification we obtained minimum and maximum tissue shear velocities ranging from 1.6 to 3.42 m/s. The reference tissue ROIs showed values from 1.31 to 4.4 m/s. 12 cases were accepted for surgical resection. The visualization of lesions with Virtual Touch Tissue Imaging confirmed the measurements of ARFI quantification and were able to depict the different areas of stiffness in the kidney tissue. No infiltration of kidney veins or vena cava was detected by contrast-enhanced ultrasound. Of the 12 cases two "complicated" renal cysts were examined, and both showed Bosniak-III findings. CONCLUSION: ARFI imaging improves visualization of unclear renal masses in comparison to fundamental B-scan and adds new information about the tissue stiffness in a less time-consuming and more reproducible way. CEUS with SonoVue allows an early evaluation of renal masses or complex cysts.

Acute renal failure by ingestion of Cortinarius species confounded with psychoactive mushrooms: a case series and literature survey.

Mushrooms of the Cortinarius species are nephrotoxic and can cause severe acute renal failure. The toxic effect is due to orellanine. It is suspected that the cytotoxic damage is caused by the production of oxygen-free radicals. Renal pathology shows tubular necrosis with interstitial nephritis. In addition to accidental intoxications as a consequence of mushroom meals, recent cases are often due to voluntary abuse of natural drugs like magic mushrooms. We report 4 current cases of acute renal failure from intoxication by Cortinarius species by confusing it with psychoactive fungi. Typical for the Cortinarius poisoning is the long latency period from ingestion until the onset of clinical symptoms (3 - 20 days). Diagnosis is based on microscopical identification of the mushroom spores, and detection of the orellanine toxin in leftover mushrooms. In renal biopsy tissue, orellanine is detectable by thin-layer chromaography technique up to 6 months after poisoning. There is no causative therapy, and treatment is symptomatic with adequate hemodialysis. In cases of otherwise unexplained acute renal failure, intoxication with nephrotoxic mushrooms should be considered.

Changes in adiponectin multimer distribution in response to atorvastatin treatment in patients with type 2 diabetes.

OBJECTIVE: Multimeric high molecular weight (HMW) forms of adiponectin were previously shown to be inversely associated with the extent of atherosclerosis in males and are down-regulated in patients with the metabolic syndrome and type 2 diabetes. In this study, potential influences of atorvastatin therapy on adiponectin multimer distribution were studied in patients with type 2 diabetes. DESIGN, PATIENTS AND MEASUREMENTS: The effect of 40 mg atorvastatin on HMW, medium molecular weight (MMW), and low molecular weight (LMW) isoforms of adiponectin were investigated in 75 patients (23 females; 52 males) with type 2 diabetes in an 8-week-long, placebo-controlled and randomized study. Adiponectin multimeric isoforms were detected by Western blot analysis. RESULTS: After atorvastatin therapy the median serum concentration of HMW adiponectin increased significantly by 42.3% (1.68 vs. 2.39 microg/ml; P < 0.001), while concentrations of MMW adiponectin and LMW adiponectin significantly decreased by 20.8% and 23.2%, respectively (MMW: 3.31 vs. 2.62 microg/ml, P = 0.047; LMW: 0.56 vs. 0.43 microg/ml, P = 0.033). Median total adiponectin levels were not significantly altered by atorvastatin treatment (6.0 vs. 6.2 microg/ml, P = 0.898). Consequently, the HMW: total-adiponectin ratio significantly increased by 25.0% (0.40 vs. 0.50; P = 0.013). CONCLUSIONS: Atorvastatin therapy is associated with significant changes in adiponectin multimer distribution in patients with type 2 diabetes. Since total adiponectin levels were not affected by intervention, atorvastatin may shift adiponectin size towards the HMW form.

Treatment of chronic allograft nephropathy at late stages using everolimus or FTY720 in combination with cyclosporine.

OBJECTIVE: In this study, we used combined treatment with cyclosporine (CsA)/everolimus (EVR) or CsA/FTY720 to affect ongoing chronic allograft nephropathy (CAN) compared with monotherapy with EVR or FTY720. BACKGROUND: CAN is an important cause of renal allograft loss. Immunosuppressive therapy is based on calcineurin inhibitors, which are associated with nephrotoxicity and decreasing graft function. Thus, alternative treatment regimens, including new immunosuppressants, such as EVR or FTY720, are of interest. We asked whether the combination of CsA with EVR or FTY720 ameliorated the development of CAN more effectively than monotherapy with EVR and/or FTY720 during the later stages of CAN. METHODS: Kidneys from Fisher rats were orthotopically transplanted into Lewis rats. Animals received CsA (1.5 mg/kg/d) for the first 10 days after transplantation. Animals were assigned to 6 groups: EVR (0.5 mg/kg/d), FTY720 (0.5 mg/kg/d), CsA (1.5 mg/kg/d), CsA+EVR (1.5 + 0.5 mg/kg/d), CsA+FTY720 (1.5 + 0.5 mg/kg/d), and vehicle (VEH). Treatment started at week 20. The observation period ended after 28 weeks. RESULTS: Treatment with EVR and FTY720 reduced proteinuria and glomerulosclerosis, suppressed lymphocyte and macrophage infiltration, and resulted in a greater number of apoptotic tubular and interstitial cells compared with the combined treatment groups and controls. CONCLUSION: Although EVR and FTY720 monotherapy delayed the progression of CAN, their combination with CsA had no beneficial effect.