[Acute renal failure in COVID-19]

Das akute Nierenversagen („acute kidney injury“, AKI) ist eine häufige Komplikation bei COVID-19 („coronavirus disease 2019“). Es geht häufig mit der progredienten respiratorischen Verschlechterung einher und ist mit einer erhöhten Morbidität und Mortalität assoziiert. Das AKI ist vermutlich multifaktorieller Genese, wobei auch ein direkter Virusbefall der Niere eine Rolle zu spielen scheint. Spezifische Behandlungsverfahren für das COVID-19-assoziierte Nierenversagen existieren aktuell nicht. Auch die Rolle extrakorporaler Verfahren in der COVID-19-Behandlung konnte bislang nicht geklärt werden. Aktuelle Daten deuten auf eine anhaltende Nierenfunktionseinschränkung nach COVID-19-assoziiertem AKI hin, sodass eine Reevaluation der Nierenfunktion nach stattgehabter Erkrankung empfohlen werden sollte.

[COVID-19 and the kidneys]

Die SARS(„severe acute respiratory syndrome“)-CoV(„coronavirus“)-2-Pandemie hat sich zu einer der größten globalen Herausforderungen unserer Zeit entwickelt. Recht schnell wurde klar, dass im Rahmen einer COVID-19(„coronavirus disease 2019“)-Erkrankung neben der Lunge auch andere Organe in unterschiedlichem Maße betroffen sind. Besonders häufig sind dies auch die Nieren. So weisen viele zuvor nierengesunde Patienten bereits zu Beginn einer COVID-19-Erkrankung Urinauffälligkeiten auf, und bei schweren Verläufen entwickelt sich oft eine akute Nierenschädigung.

[COVID-19 and the kidneys]

Welche drastischen Folgen neue Infektionskrankheiten für Mensch und Gesellschaft haben können, wird aktuell an COVID-19 („coronavirus disease 2019“) deutlich. Seit seiner Erstbeschreibung im Dezember 2019 beherrscht SARS-CoV‑2 („severe acute respiratory syndrome coronavirus 2“) das aktuelle wissenschaftliche und öffentliche Interesse.

The lung microbiome in patients with pneumocystosis

Backround

Pneumocystis jirovecii pneumonia (PCP) is an opportunistic fungal infection that is associated with a high morbidity and mortality in immunocompromised individuals. In this study, we analysed the microbiome of the lower respiratory tract from critically ill intensive care unit patients with and without pneumocystosis.

Methods

Broncho-alveolar fluids from 65 intubated and mechanically ventilated intensive care unit patients (34 PCP+ and 31 PCP- patients) were collected. Sequence analysis of bacterial 16S rRNA gene V3/V4 regions was performed to study the composition of the respiratory microbiome using the Illumina MiSeq platform.

Results

Differences in the microbial composition detected between PCP+ and PCP- patients were not statistically significant on class, order, family and genus level. In addition, alpha and beta diversity metrics did not reveal significant differences between PCP+ and PCP- patients. The composition of the lung microbiota was highly variable between PCP+ patients and comparable in its variety with the microbiota composition of the heterogeneous collective of PCP- patients.

Conclusions

The lower respiratory tract microbiome in patients with pneumocystosis does not appear to be determined by a specific microbial composition or to be dominated by a single bacterial species.

Electronic supplementary material

The online version of this article (10.1186/s12890-017-0512-5) contains supplementary material, which is available to authorized users.

Effect of ABO incompatibility on T-cell flow cytometry cross-match results prior to living donor kidney transplantation

BACKGROUND

Due to its high sensitivity, the flow cytometry cross-match (FCXM) has been described as valuable tool for identifying an optimal donor. We here focused on the impact of ABO incompatibility on FCXM results.

METHODS

We analyzed 29 ABO incompatible and 89 ABO compatible donor-recipient pairs (73 and 175 datasets, respectively) prior to living donor kidney transplantation. In all patients, lymphocytotoxic cross-matches for B and T cells were negative.

RESULTS

Recipients with blood group O (A to O and B to O) displayed significantly (P < 0.05) higher T-FCXM results than those with blood group A and B (A to B, B to A and AB to A), respectively. Donor-specific T-FCXM responses (ΔMFI values) were significantly higher (P < 0.05) in ABO incompatible vs. compatible pairs (ABO incompatible recipients with blood group O: 32 ± 6; with blood group A: 19 ± 7; with blood group B: 7 ± 4; recipients with ABO compatibility: 3 ± 2, respectively, data represent mean ± SEM). Consistent with the T-FCXM results donor-specific isohemagglutinins (IgG titers) were significantly higher in recipients with blood group O vs. A, both prior to rituximab treatment and plasmapheresis/immune adsorption (P = 0.004) and immediately prior to transplantation, i.e., after rituximab and antibody-depleting therapies (P = 0.04).

CONCLUSIONS

ABO incompatibility was associated with higher T-FCXM responses, especially in recipients with blood group O. This finding has major impact on the interpretation of flow cross-match results. Current cut-off values need to be reassessed in the ABO incompatible setting. © 2016 International Clinical Cytometry Society.

Diagnostics and treatment of a severe humoral rejection after liver transplantation: donor-specific antibodies as a still underestimated cause of graft failure

BACKGROUND

Donor-specific antibodies (DSAs) are increasingly being considered a cause of complications after liver transplant (LT). However, neither monitoring of DSAs nor the appropriate therapeutic procedures for humoral graft damage are yet standardized. Here we report a case of DSA-positive humoral rejection after LT that was successfully treated with plasmapheresis and immunoglobulins.

METHODS

Human leukocyte antigen (HLA)-specific DSAs were detected by Luminex bead assay. Patient characteristics, laboratory values, and data about the patient's general condition were documented from April 2013 to June 2015.

CASE REPORT

Eighteen months after LT, a 54-year-old man experienced severe hepatopathy with rapidly increasing transaminase activity and total bilirubin levels. Histologic findings were inconclusive, demonstrating chronic cholestasis and minimal positive staining for C4 d. However, an analysis for anti-HLA antibodies detected DSAs against HLA class II molecules with high mean fluorescence intensity. The patient underwent 8 courses of plasmapheresis, resulting in sustained amelioration of his condition and decreases in bilirubin levels and transaminase activity.

CONCLUSION

De novo DSAs can be responsible for graft failure after LT. Thus, procedures aimed at detecting DSAs are recommended, and regular monitoring of DSAs after LT is important for individualized risk management. Plasmapheresis is an efficient therapeutic procedure for DSA-associated graft failure.

Endothelial progenitor cells are differentially impaired in ANCA-associated vasculitis compared to healthy controls

Background

Endothelial progenitor cells (EPC) are of major importance in vascular repair under healthy circumstances. Vascular injury in need of repair occurs frequently in ANCA-associated vasculitis (AAV). A specialized T cell subset enhancing EPC function and differentiation has recently been described. These angiogenic T cells (T_ang) may have an important impact on the vascular repair process. Therefore, the aim of our study was to investigate EPC and T_ang in AAV.

Methods

Fifty-three patients suffering from AAV and 29 healthy controls (HC) were enrolled in our study. Forty-four patients were in remission, nine patients were in active state of disease. Patients were either untreated or were under monotherapy with low-dose steroids (max. 5 mg/day) at the time of sampling. Circulating EPC and T_ang were determined by flow cytometry (FACS). The functional capacity of EPC was assessed by established cell culture methods.

Results

Circulating EPC were significantly decreased in AAV as compared to HC. The capacity of EPC to differentiate and proliferate was differentially impaired in patients as compared to HC. The outgrowth of endothelial colony-forming cells (ECFC) was severely decreased in patients whereas colony-forming units-endothelial cell (CFU-EC) outgrowth was unaffected. ECFC and CFU-EC differentiation was strictly T cell-dependent. Patients with a relapsing disease course had an impaired ECFC outgrowth and expansion of T_ang as compared to patients with a stable, nonrelapsing disease.

Conclusions

The differentiation process of EPC is impaired in AAV. This may favor insufficient vascular repair promoting a relapsing disease course. Finally, these factors may explain a higher cardiovascular morbidity as has been previously documented in AAV.

Decreased IL-10(+) regulatory B cells (Bregs) in lupus nephritis patients

OBJECTIVES

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by B cell-dependent autoantibody production. Recently, a new B-cell subset was discovered that has a regulatory capacity. The aim of this study was to analyse regulatory B cells (Bregs) in SLE patients.

METHOD

Peripheral mononuclear blood cells (PBMCs) of 34 SLE patients fulfilling the American College of Rheumatology (ACR) criteria for SLE and 21 healthy controls (HC) were included. PBMCs were stained for CD19, CD24, and CD38 and analysed by flow cytometry. In vitro stimulated PBMCs with CpG and restimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin were investigated for IL-10(+) Bregs .

RESULTS

The percentages of circulating CD19(+)CD24(hi)CD38(hi) cells in HC were not different those in from SLE patients. The percentages of IL-10(+) Bregs were significantly decreased in SLE patients, in particular those with lupus nephritis (LN), compared to HC. The proportion was independent of disease activity.

CONCLUSIONS

This is the first study to demonstrate a decrease in IL-10-producing B cells in LN patients compared to HC, reflecting an impaired regulatory function.

Five-year outcomes in kidney transplant patients converted from cyclosporine to everolimus: the randomized ZEUS study

ZEUS study was an open-label, 12-month, multicenter study in which 300 de novo kidney transplant recipients were randomized to continue receiving cyclosporine (CsA) or convert to everolimus at 4.5 months posttransplant. Five-year follow-up data were available for 245/269 patients (91.1%) who completed the core 12-month study (123 everolimus, 109 CsA). At 5 years, adjusted estimated GFR was 66.2 mL/min/1.73 m(2) with everolimus versus 60.9 mL/min/1.73 m(2) with CsA; the mean difference was 5.3 mL/min/1.73 m(2) in favor of everolimus (95% CI 2.4, 8.3; p < 0.001 [intent-to-treat population]). In a post hoc analysis of patients remaining on study drug at 5 years (everolimus 77, CsA 86), mean difference was 8.2 mL/min/1.73 m(2) (95% CI 4.3, 12.1; p < 0.001) in favor of everolimus. The cumulative incidence of biopsy-proven acute rejection postrandomization was 13.6% with everolimus versus 7.5% with CsA (p = 0.095), largely accounted for by grade I rejection (16/21 patients and 7/11 patients, respectively). Postrandomization, graft loss, mortality, serious adverse events and neoplasms were similar in both arms. In conclusion, conversion of kidney transplant patients to everolimus at 4.5 months posttransplant is associated with a significant improvement in renal function that is maintained to at least 5 years. The increase in early mild acute rejection did not affect long-term graft function.

[Comparison of extracorporeal liver assist devices - albumin dialysis versus plasma exchange - in acute-on-chronic liver failure]

BACKGROUND AND AIM

Extracorporeal liver assist devices are besides causal and symptomatic approaches important therapeutic options in acute-on-chronic (AOC) liver failure. In this retrospective analysis, albumin dialysis was compared to therapeutic plasma exchange (TPA) under various aspects.

PATIENTS AND METHODS

Data from 20 patients per group (10 women, 10 men in each group, mean age 51 ± 12,6 years and 48,2 ± 15,2 years, respectively) treated over a period of 3 months were analyzed. During the first treatment, 5 sessions of dialysis were performed (week 1) for both procedures, 3 more sessions were completed in the second and in the third week each. Data were acquired on days 1, 8, 13, 20, 28 and 90.

RESULTS

After 28 days, 13 out of 20 patients following albumin dialysis and 7 out of 20 patients following plasma exchange had survived (p = 0,11). After 90 days, 10 patients following albumin dialysis and 5 patients following plasma exchange were alive (p = 0,19). Degree of hepatic encephalopathy (HE) had not improved significantly. Rates of complication (infections, bleeding or system clotting) were similar under both procedures.

CONCLUSION

Extracorporeal liver assist devices can be considered equally well as a therapeutic option in acute-on-chronic liver failure. Differences in 90-day survival were not observed in our study.

Increased percentages of PD-1 on CD4+ T cells is associated with higher INF-γ production and altered IL-17 production in patients with systemic lupus erythematosus

OBJECTIVES

Programmed death (PD)-1 is a cell death receptor that, upon stimulation, leads to apoptosis. Previous studies have shown alteration of PD-1 expression on T cells and PD-1 genes in patients with systemic lupus erythematosus (SLE). The aim of this study was to assess the expression of this receptor on effector T cells in patients with SLE.

METHOD

In this study we enrolled 32 SLE patients and 31 healthy controls. T cells from peripheral blood were analysed by flow cytometry for the expression of PD-1. Interferon (IFN)-γ and interleukin (IL)-17-producing cells were investigated for the expression of this co-stimulatory marker.

RESULTS

Percentages of CD4(+) T cells expressing PD-1 were significantly increased in patients with SLE compared to healthy controls. The percentage of PD-1 expression was correlated with the production of INF-γ (r = 0.83, p < 0.0001). We also investigated the production of IL-17 by PD-1(+) CD3(+) T cells. Inactive patients (3.2 ± 1.2% vs. 5.9 ± 3.5%, p = 0.002) and patients without lupus nephritis (LN) (3.2 ± 1.5% vs. 5.9 ± 3.5%, p = 0.005) showed lower levels of IL-17 compared to healthy controls.

CONCLUSION

We have demonstrated increased expression of PD-1 on CD4(+) T cells in SLE patients and an association between PD-1 expression on CD4(+) T cells and IFN-γ expression on CD3(+) T cells. We have also shown that there is an altered subset of PD-1(+) T cells in inactive patients and patients without LN producing lower amounts of IL-17.

[Outbreak with Ralstonia pickettii caused by contaminated magnesium vials]

HISTORY

In February 2013, 5 patients in an intensive care unit (ICU) were found to have positive blood cultures with Ralstonia pickettii within one week. Because all patients got intravenous therapy, improper work of a staff member was suspected. Some days later, a 6th patient was found with a positive blood culture of Ralstonia pickettii in another department of the hospital.

INVESTIGATIONS

Hygienic investigations showed no evidence of failures in preparation of intravenous therapy. All patients were on different intravenous drugs, but every patient had received glucose 5 % and magnesium. We examined samples of glucose and magnesia as well as samples from environment. RESULTS AND COURSE: Glucose and magnesium samples were examined by membrane filter method. Ralstonia pitteckii was detected in some Magnesium vials. We concluded, that contamination of Magnesium vials might have been the reason for blood stream infection of patients. Pharmacists and authorities were informed and all vials were collected and replaced by vials from another company. Later a nationwide recall of Magnesium vials was performed by the producing company. No further Ralstonia pickettii was found in blood cultures in our hospital.

CONCLUSION

Unusual pathogens in blood cultures should lead to reflection of rarer causes such as contamination of medicines.

A patient with severe respiratory failure caused by novel human coronavirus

We report a case of a 45-year-old patient who developed severe acute respiratory distress syndrome accompanied by renal failure. An infection with a novel human coronavirus was confirmed and found to be the reason for rapidly progressive respiratory failure of our patient.

Efficacy of sotrastaurin plus tacrolimus after de novo kidney transplantation: randomized, phase II trial results

Sotrastaurin, a novel immunosuppressant, blocks early T cell activation through protein kinase C inhibition. Efficacy and safety of sotrastaurin with tacrolimus were assessed in a dose-ranging non-inferiority study in renal transplant recipients. A total of 298 patients were randomized 1:1:1:1 to receive sotrastaurin 100 (n = 77; discontinued in December 2011) or 200 mg (n = 73) b.i.d. plus standard tacrolimus (sTAC; 5-12 ng/mL), sotrastaurin 300 mg (n = 75) b.i.d. plus reduced tacrolimus (rTAC; 2-5 ng/mL) or enteric-coated mycophenolic acid (MPA) plus sTAC (n = 73); all patients received basiliximab and corticosteroids. Composite efficacy failure (treated biopsy-proven acute rejection ≥ grade IA, graft loss, death or loss to follow up) rates at Month 12 were 18.8%, 12.4%, 10.9% and 14.0% for the sotrastaurin 100, 200 and 300 mg, and MPA groups, respectively. The median estimated glomerular filtration rates were 55.7, 53.3, 64.9 and 59.2 mL/min, respectively. Mean heart rates were faster with higher sotrastaurin doses and discontinuations due to adverse events and gastrointestinal adverse events were more common. Fewer patients in the sotrastaurin groups experienced leukopenia than in the MPA group (1.3-5.5% vs. 16.5%). Sotrastaurin 200 and 300 mg had comparable efficacy to MPA in prevention of rejection with no significant difference in renal function between the groups.

Stented ureterovesical anastomosis in renal transplantation: does it influence the rate of urinary tract infections?

Objective

Our objective was to evaluate the impact of routine use of double-J stents on the incidence of urinary tract infection after renal transplantation.

Methods

We conducted a retrospective-comparative single-centre study in 310 consecutive adult deceased donor kidney recipients transplanted from 2002 to 2006. Patients were divided in two groups, with or without urinary stent implantation. To evaluate the predictive factors for UTI, donor and recipients pre- and post-transplantation data were analysed. Early urological complications and renal function within 12 months of transplantation were included as well.

Results

A total of 157 patients were enrolled to a stent (ST) and 153 patients to a no-stent (NST) group. The rate of urinary tract infection at three months was similar between the two groups (43.3% ST vs. 40.1% NST, p = 0.65). Of the identified pathogens Enterococcus and Escherichia coli were the most common species. In multivariate analysis neither age nor immunosuppressive agents, BMI or diabetes seemed to have influence on the rate of UTI. When compared to males, females had a significantly higher risk for UTI (54.0% vs. 33.5%).

Conclusion

Prophylactic stenting of the ureterovesical anastomosis does not increase the risk of urinary tract infection in the early postoperative period.

Peripherally circulating CD4⁺ FOXP3⁺ CXCR3⁺ T regulatory cells correlate with renal allograft function

Peripheral immunoregulation depends on T regulatory cell trafficking into the allograft to modulate the local alloresponse. Little is known about the relevance of trafficking receptors for Tregs after solid organ transplantation in humans. In this study, expression of the peripheral chemokine receptors CXCR3 and CCR5 on CD4⁺ FOXP3⁺ Treg cells was analysed and correlated with allograft function in renal transplant recipients. Flow cytometry analysis of peripheral blood mononuclear cells of 54 renal transplant recipients receiving a calcineurin inhibitor-based immunosuppression was performed for CD4, CD25, FOXP3, CXCR3 and CCR5 within the first 18 months post-transplantation. Correlation analysis of chemokine receptor expression and glomerular filtration rate as calculated by MDRD (eGFR) was performed. Expression of the peripheral homing receptors CXCR3 (r = 0.44, P < 0.05) and CCR5 (r = 0.45, P < 0.05) on FOXP3⁺ Tregs correlated with renal allograft function (eGFR) in patients receiving tacrolimus (n = 28), but not cyclosporine A (CsA) (n = 26). CsA but not tacrolimus reduced surface expression of CXCR3 on FOXP3⁺ Tregs in renal transplant recipients as correlated to trough levels (r = -0.42, P < 0.05). In contrast to CD4⁺ CXCR3⁺ CD25(lo) T cells, flow-sorted CD4⁺ CXCR3⁺ CD25(hi) Tregs isolated from healthy individuals did not produce IFNγ or IL-17 ex vivo and expressed high levels of GARP mRNA both at baseline as well as after TCR activation indicating functional regulatory activity. Expression of the peripheral trafficking receptors CXCR3 and CCR5 on FOXP3⁺ Tregs is associated with renal allograft function. These results suggest that Treg trafficking may also depend on the interaction of CXCR3 or CCR5 and their respective ligands.

Cyclosporin but not everolimus inhibits chemokine receptor expression on CD4+ T cell subsets circulating in the peripheral blood of renal transplant recipients

The peripheral chemokine receptors chemokine receptor 3 (CXCR3) and CC chemokine receptor 5 (CCR5) have been reported to be associated with allograft rejection. The impact of the expression of immunosuppressive drugs on peripherally circulating CD4(+) T cell subsets after renal transplantation is unknown. Expression of CXCR3 and CCR5 was investigated by flow cytometry in 20 renal allograft recipients participating in a prospective, randomized trial (NCT00514514). Initial immunosuppression consisted of basiliximab, cyclosporin A (CsA), mycophenolate sodium and corticosteroids. After 3 months, patients were treated either with CsA, mycophenolate sodium (MPA) plus corticosteroids (n = 6), CsA and everolimus plus corticosteroids (n =8) or CsA-free (CsA(free)) receiving everolimus, MPA and corticosteroids (n = 6). After initial reduction of CD4(+) forkhead box protein 3 (FoxP3)(+) and CD4(+) CD25(hi) FoxP3(+) regulatory T cells (T(regs)) (P < 0.05; P < 0.01), 3-month post-transplant percentages of T(regs) were reconstituted in CsA(free) and CsA(lo) arms compared to CsA(reg) 12 months post transplant. Expression of CCR5 and CXCR3 on CD4(+) FoxP3(+) and CD4(+) FoxP3(-) T cells 12 months post transplant was increased in CsA(free) versus CsA(reg). Increase in CCR5(+) CXCR3(+) co-expressing CD4(+) FoxP3(-) cells between 3 and 12 months correlated negatively with the glomerular filtration rate (GFR) slope/year [modification of diet in renal disease (MDRD); r = -0.59, P < 0.01]. CsA, but not everolimus, inhibits both T(reg) development and expression of CXCR3 and CCR5 on CD4(+) T cell subsets. Increase in CCR5(+) CXCR3(+) co-expressing CD4(+) FoxP3(-) T cells is associated with early loss in allograft function.

Conversion from cyclosporine to everolimus at 4.5 months posttransplant: 3-year results from the randomized ZEUS study

The long-term effect of conversion from calcineurin inhibitor (CNI) therapy to an mTOR inhibitor requires clarification. Following completion of the 12-month, open-label, multicenter ZEUS study, in which 300 kidney transplant recipients were randomized to continue cyclosporine (CsA) or convert to everolimus at 4.5 months posttransplant, outcomes were assessed at month 36 (n = 284; 94.7%). CNI therapy was reintroduced in 28.4% of everolimus patients by month 36. The primary efficacy endpoint, estimated glomerular filtration rate (Nankivell, ANCOVA) was significantly higher with everolimus versus the CsA group at month 24 (7.6 mL/min/1.73 m(2) , 95%CI 4.3, 11.0 mL/min/1.73 m(2) ; p < 0.001) and month 36 (7.5 mL/min/1.73 m(2) , 95%CI 3.6, 11.4 mL/min/1.73 m(2) ; p < 0.001). The incidence of biopsy-proven acute rejection from randomization to month 36 was 13.0% in the everolimus arm and 4.8% in the CsA arm (p = 0.015). Patient and graft survival, as well as incidences of malignancy, severe infections and hospitalization, were similar between groups. Kidney transplant patients who are converted from CsA to everolimus at month 4.5 and who remain on everolimus thereafter may achieve a significant improvement in renal function that is maintained to 3 years. There was a significantly higher rate of rejection in the everolimus arm but this did not exert a deleterious effect by 3 years posttransplant.

[Managing EHEC in hospital routine]

BACKGROUND

During May and June 2011 an outbreak of enterohemorrhagic Escherichia coli (EHEC) occurred in Germany. More than 4000 patients were infected of which 800 developed hemolytic uremic syndrome (HUS) as a severe complication. Reports in the press led to great concern in the general population. Many people with diarrhea reported to hospitals in order to exclude EHEC infections.

METHODS

We describe the management of patients with suspected infectious diarrhea at the university hospital of Essen. A hospital with a significant number of immunocompromised patients.

RESULTS

One important measure to handle the surge of contagious patients was to establish a multidisciplinary coordination team under leadership and guidance of the Department of Nephrology and the Department of Hospital Hygiene. Suspected infectious patients were separated in a modified emergency room. A new ward for infectious diseases was established to isolate in-patients.

CONCLUSION

In our hospital the management of EHEC outbreak enabled us to treat these additional infectious patients without hampering the treatment of the other patients. As a result we plan the implementation of a coordination team for future epidemics.

Plasma noradrenaline and state anxiety levels predict placebo response in learned immunosuppression

Large interindividual differences exist in the presence and extent of placebo responses in both experimental and clinical studies, but little is known about possible predictors of these responses. We employed a behaviorally conditioned immunosuppression paradigm in healthy men to analyze predictors of learned placebo responses. During acquisition, the subjects received either the immunosuppressant cyclosporin A (n = 32) or a placebo (n = 14) (unconditioned stimuli (US)) together with a novel-tasting drink (conditioned stimulus (CS)). During evocation, the subjects were reexposed to the CS alone. In responders (n = 15), the CS alone caused a significant inhibition of interleukin (IL)-2 production by anti-CD3-stimulated peripheral blood T cells, closely mimicking the drug effect. Nonresponders (n = 17) did not show responses different from those of the controls. Multiple-regression analyses showed that baseline IL-2, plasma noradrenaline, and state anxiety predicted nearly 60% of the variance in the conditioned IL-2 response. These data provide first evidence for putative biological and psychological predictors of learned placebo responses.

[Urinary tract infections after kidney transplantation: Essen algorithm for calculated antibiotic treatment]

Urinary tract infections are the most common infection early after transplantation and can affect long-term graft function. Any urinary tract infection in renal transplant recipients should be seen as "complex" with regard to consequences for diagnosis and therapy. The increase in resistance to anti-infective agents seen among uropathogens is one of the central therapeutic problems. This means for routine clinical practice that contact isolation precautions should be consistently implemented for affected patients and the duration of introducing urinary tract instruments should be minimized. Detection of pyuria and urine cultures are required to confirm infection, to identify the corresponding pathogen, and to review the antibiotic therapy.The "Essen algorithm for calculated antibiotic treatment of urinary tract infections in renal transplant patients" takes into consideration the high incidence of Gram-negative pathogens in general and the increased incidence of enterococci in the early phase after transplantation. Within the first 2 months after transplantation quinolones should be used and later cephalosporins. In case of urosepsis, calculated antibiotic therapy should cover problematic Gram-negative pathogens such as pseudomonades. The calculated antibiotic therapy should be administered intravenously in severe infections. In any case the local and regional antibiotic susceptibility should be taken into account when deciding on the calculated antibiotic therapy.

Pulse wave velocity predicts mortality in renal transplant patients

Background

Measuring arterial stiffness using pulse wave velocity (PWV) has become an important tool to assess vascular function and cardiovascular mortality. For subject with hypertension, end-stage renal disease and diabetes, PWV has been shown to predict cardiovascular and all-cause mortality. We hypothesize that PWV would also predict mortality in subjects who have undergone kidney transplantation.

Methods

A cohort of 330 patients with renal transplantation was studied with a mean age at entry 51.4 ± 0.75 years. Mean follow-up was 3.8 years (± 0.7 years); 16 deaths occurred during follow-up. At entry, together with standard clinical and biochemical parameters, PWV was determined from pressure tracing over carotid and femoral arteries.

Results

With increasing PWV, there was a significant increase in age, systolic blood pressure and pulse pressure. In addition, subjects with higher PWV also exhibited more frequently the presence of coronary heart disease. On the basis of Cox analyses, PWV and systolic blood pressure emerged as predictors of all-cause mortality.

Conclusion

These results provide evidence that PWV is a strong predictor of all-cause mortality in the population of renal transplant recipients.

Noninvasive detection of graft rejection by in vivo (19) F MRI in the early stage

Diagnosis of transplant rejection requires tissue biopsy and entails risks. Here, we describe a new (19) F MRI approach for noninvasive visualization of organ rejection via the macrophage host response. For this, we employed biochemically inert emulsified perfluorocarbons (PFCs), known to be preferentially phagocytized by monocytes and macrophages. Isografts from C57BL/6 or allografts from C57B10.A mice were heterotopically transplanted into C57BL/6 recipients. PFCs were applied intravenously followed by (1) H/(19) F MRI at 9.4 T 24 h after injection. (1) H images showed a similar position and anatomy of the graft in the abdomen for both cases. However, corresponding (19) F signals were only observed in allogenic tissue. (1) H/(19) F MRI enabled us to detect the initial immune response not later than 3 days after surgery, when conventional parameters did not reveal any signs of rejection. In allografts, the observed (19) F signal strongly increased with time and correlated with the extent of rejection. In separate experiments, rapamycin was used to demonstrate the ability of (19) F MRI to monitor immunosuppressive therapy. Thus, PFCs can serve as positive contrast agent for the early detection of transplant rejection by (19) F MRI with high spatial resolution and an excellent degree of specificity due to lack of any (19) F background.

Impact of immunosuppressive therapy on hepatitis C infection after renal transplantation

BACKGROUND

Among patients after renal transplantation (NTx), hepatitis C virus (HCV) infection is a risk factor for graft loss and patient death caused by hepatic decompensation. Also, HCV has been implicated in the pathogenesis of glomerular diseases in native and transplanted kidneys. Therefore, the aim of this retrospective cohort study was to determine the effects of the widely used calcineurin inhibitors (CNI) cyclosporine A (CsA) and tacrolimus (Tac) on hepatitis C virus replication, inflammatory activity, development of liver fibrosis, and long-term renal graft function.

SUBJECTS AND METHODS

A cohort of 71 patients with HCV infection after kidney transplantation under immunosuppression with either CsA or Tac were analyzed for viral kinetics and serum transaminases. In addition, presence of liver fibrosis was detected by non-invasive measurements using the FibroScan. Graft function was determined biochemically. Patients with interferon therapy prior to transplantation were excluded from the study in order to avoid any impact of the antiviral therapy on outcomes.

RESULTS

In the early period after transplantation, hepatitis C viral load was lower in patients treated with Tac as compared to CsA. This effect became negligible 3 months after transplantation. However, hepatic inflammatory activity was reduced in the CsA-treated group. Extent of liver fibrosis was similar in both groups of HCV-infected patients as well as in a control group of non-HCV-infected patients after renal transplantation (NTx), respectively. Renal function and glomerular filtration rate, as calculated by the modification of diet in renal disease (MDRD) formula, were significantly better in patients treated with Tac.

CONCLUSIONS

During long-term immunosuppression, the CNIs cyclosporine A versus tacrolimus showed no significant differences in HCV-infected patients after renal transplantation with respect to viral replication and development of liver fibrosis. However, function of the renal graft is significantly better preserved in patients receiving tacrolimus.