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Treatment of carbapenemase‐producing Enterobacteralesbloodstream infections in solid organ transplant recipients is challenging. The objective of this study was to develop a specific score to predict mortality in solid organ transplant recipients with carbapenemase‐producing Enterobacteralesbloodstream infections. A multinational, retrospective (2004‐2016) cohort study (INCREMENT‐SOT, ClinicalTrials.gov NCT02852902) was performed. The main outcome variable was 30‐day all‐cause mortality. The INCREMENT‐SOT‐CPE score was developed using logistic regression. The global cohort included 216 patients. The final logistic regression model included the following variables: INCREMENT‐CPE mortality score ≥8 (8 points), no source control (3 points), inappropriate empirical therapy (2 points), cytomegalovirus disease (7 points), lymphopenia (4 points), and the interaction between INCREMENT‐CPE score ≥8 and CMV disease (minus 7 points). This score showed an area under the receiver operating characteristic curve of 0.82 (95% confidence interval [CI] 0.76‐0.88) and classified patients into 3 strata: 0‐7 (low mortality), 8‐11 (high mortality), and 12‐17 (very‐high mortality). We performed a stratified analysis of the effect of monotherapy vs combination therapy among 165 patients who received appropriate therapy. Monotherapy was associated with higher mortality only in the very‐high (adjusted hazard ratio [HR] 2.82, 95% CI 1.13‐7.06, P= .03) and high (HR 9.93, 95% CI 2.08‐47.40, P= .004) mortality risk strata. A score‐based algorithm is provided for therapy guidance. The authors develop a predictive risk score for a solid organ transplant recipient's for mortality in patients with bloodstream infections due to carbapenemase‐producing Enterobacterales, which is useful to differentiate patients who can be treated with antimicrobial monotherapy from those who should receive combination therapy.

Clostridium difficileinfection (CDI) is a leading cause of infectious diarrhea in solid organ transplant recipients (SOT). We aimed to assess incidence, risk factors, and outcome of CDI within the Swiss Transplant Cohort Study (STCS). We performed a case-control study of SOT recipients in the STCS diagnosed with CDI between May 2008 and August 2013. We matched 2 control subjects per case by age at transplantation, sex, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors and evaluate outcome of CDI. Two thousand one hundred fifty-eight SOT recipients, comprising 87 cases of CDI and 174 matched controls were included. The overall CDI rate per 10 000 patient days was 0.47 (95% confidence interval ([CI] 0.38-0.58), with the highest rate in lung (1.48, 95% CI 0.93-2.24). In multivariable analysis, proven infections (hazard ratio [HR] 2.82, 95% CI 1.29-6.19) and antibiotic treatments (HR 4.51, 95% CI 2.03-10.0) during the preceding 3 months were independently associated with the development of CDI. Despite mild clinical presentations, recipients acquiring CDI posttransplantation had an increased risk of graft loss (HR 2.24, 95% CI 1.15-4.37; P= .02). These findings may help to improve the management of SOT recipients.

BK polyomavirus (BKPyV) causes premature kidney transplant (KT) failure in 1–15% of patients. Because antivirals are lacking, most programs screen for BKPyV-viremia and, if positive, reduce immunosuppression. To evaluate the relationship of viremia and BKPyV-specific immunity, we examined prospectively cryopreserved plasma and peripheral blood mononuclear cells at the time of transplantation (T0) and at 6 mo (T6) and 12 mo (T12) after transplant from 28 viremic KT patients and 68 nonviremic controls matched for the transplantation period. BKPyV IgG seroprevalence was comparable between cases (89.3%) and controls (91.2%; p = 0.8635), but cases had lower antibody levels (p = 0.022) at T0. Antibody levels increased at T6 and T12 but were not correlated with viremia clearance. BKPyV-specific T cell responses to pools of overlapping 15mers (15mer peptide pool [15mP]) or immunodominant CD8 9mers (9mer peptide pool [9mP]) from the early viral gene region were not different between cases and controls at T0; however, clearance of viremia was associated with stronger 9mP responses at T6 (p = 0.042) and T12 (p = 0.048), whereas 15mP responses were not informative (T6 p = 0.359; T12 p = 0.856). BKPyV-specific T cells could be expanded in vitrofrom all patients after transplant, permitting identification of 78 immunodominant 9mer epitopes including 50 new ones across different HLA class I. Thus, 9mP-responses may be a novel marker of reconstituting CD8 T cell function that warrants further study as a complement of plasma BKPyV loads for guiding immunosuppression reduction.

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person-years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5–5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7–14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2–4] versus 9.8% [95% CI 8.4–11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus-positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.

Metabolic syndrome after transplantation is a major concern following solid organ transplantation (SOT). The CREB-regulated transcription co-activator 2 (CRTC2) regulates glucose metabolism. The effect of CRTC2polymorphisms on new-onset diabetes after transplantation (NODAT) was investigated in a discovery sample of SOT recipients (n1=197). Positive results were tested for replication in two samples from the Swiss Transplant Cohort Study (STCS, n2=1294 and n3=759). Obesity and other metabolic traits were also tested. Associations with metabolic traits in population-based samples (n4=46’186, n5=123’865, n6>100,000) were finally analyzed. In the discovery sample, CRTC2 rs8450-AAgenotype was associated with NODAT, fasting blood glucose and body mass index (Pcorrected<0.05). CRTC2 rs8450-AAgenotype was associated with NODAT in the second STCS replication sample (odd ratio (OR)=2.01, P=0.04). In the combined STCS replication samples, the effect of rs8450-AAgenotype on NODAT was observed in patients having received SOT from a deceased donor and treated with tacrolimus (n=395, OR=2.08, P=0.02) and in non-kidney transplant recipients (OR=2.09, P=0.02). Moreover, rs8450-AAgenotype was associated with overweight or obesity (n=1215, OR=1.56, P=0.02), new-onset hyperlipidemia (n=1007, OR=1.76, P=0.007), and lower high-density lipoprotein-cholesterol (n=1214, β=-0.08, P=0.001). In the population-based samples, a proxy of rs8450G>Awas significantly associated with several metabolic abnormalities. CRTC2 rs8450G>Aappears to have an important role in the high prevalence of metabolic traits observed in patients with SOT. A weak association with metabolic traits was also observed in the population-based samples.

The prognostic factors and optimal therapy for invasive pulmonary aspergillosis (IPA) after kidney transplantation (KT) remain poorly studied. We included in this multinational retrospective study 112 recipients diagnosed with probable (75.0% of cases) or proven (25.0%) IPA between 2000 and 2013. The median interval from transplantation to diagnosis was 230 days. Cough, fever, and expectoration were the most common symptoms at presentation. Bilateral pulmonary involvement was observed in 63.6% of cases. Positivity rates for the galactomannan assay in serum and bronchoalveolar lavage samples were 61.3% and 57.1%, respectively. Aspergillus fumigatuswas the most commonly identified species. Six- and 12-week survival rates were 68.8% and 60.7%, respectively, and 22.1% of survivors experienced graft loss. Occurrence of IPA within the first 6 months (hazard ratio [HR]: 2.29; p-value = 0.027) and bilateral involvement at diagnosis (HR: 3.00; p-value = 0.017) were independent predictors for 6-week all-cause mortality, whereas the initial use of a voriconazole-based regimen showed a protective effect (HR: 0.34; p-value = 0.007). The administration of antifungal combination therapy had no apparent impact on outcome. In conclusion, IPA entails a dismal prognosis among KT recipients. Maintaining a low clinical suspicion threshold is key to achieve a prompt diagnosis and to initiate voriconazole therapy.

Most countries exclude human immunodeficiency virus (HIV)-positive patients from organ donation because of concerns regarding donor-derived HIV transmission. The Swiss Federal Act on Transplantation has allowed organ transplantation between HIV-positive donors and recipients since 2007. We report the successful liver transplantation from an HIV-positive donor to an HIV-positive recipient. Both donor and recipient had been treated for many years with antiretroviral therapy and harbored multidrug-resistant viruses. Five months after transplantation, HIV viremia remains undetectable. This observation supports the inclusion of appropriate HIV-positive donors for transplants specifically allocated to HIV-positive recipients.

Risk factors for invasive pulmonary aspergillosis (IPA) after kidney transplantation have been poorly explored. We performed a multinational case–control study that included 51 kidney transplant (KT) recipients diagnosed with early (first 180 posttransplant days) IPA at 19 institutions between 2000 and 2013. Control recipients were matched (1:1 ratio) by center and date of transplantation. Overall mortality among cases was 60.8%, and 25.0% of living recipients experienced graft loss. Pretransplant diagnosis of chronic pulmonary obstructive disease (COPD; odds ratio [OR]: 9.96; 95% confidence interval [CI]: 1.09–90.58; p = 0.041) and delayed graft function (OR: 3.40; 95% CI: 1.08–10.73; p = 0.037) were identified as independent risk factors for IPA among those variables already available in the immediate peritransplant period. The development of bloodstream infection (OR: 18.76; 95% CI: 1.04–339.37; p = 0.047) and acute graft rejection (OR: 40.73, 95% CI: 3.63–456.98; p = 0.003) within the 3 mo prior to the diagnosis of IPA acted as risk factors during the subsequent period. In conclusion, pretransplant COPD, impaired graft function and the occurrence of serious posttransplant infections may be useful to identify KT recipients at the highest risk of early IPA. Future studies should explore the potential benefit of antimold prophylaxis in this group.

In this nationwide cohort of solid organ transplant recipients, the authors find that the incidence of cytomegalovirus disease is similar irrespective of the antiviral preventive strategy used (preemptive vs. prophylaxis), although patients who received antiviral prophylaxis have better graft failure‐free survival.

We assessed the impact of antiviral prophylaxis and preemptive therapy on the incidence and outcomes of cytomegalovirus (CMV) disease in a nationwide prospective cohort of solid organ transplant recipients. Risk factors associated with CMV disease and graft failure-free survival were analyzed using Cox regression models. One thousand two hundred thirty-nine patients transplanted from May 2008 until March 2011 were included; 466 (38%) patients received CMV prophylaxis and 522 (42%) patients were managed preemptively. Overall incidence of CMV disease was 6.05% and was linked to CMV serostatus (D+/R− vs. R+, hazard ratio [HR] 5.36 [95% CI 3.14–9.14], p < 0.001). No difference in the incidence of CMV disease was observed in patients receiving antiviral prophylaxis as compared to the preemptive approach (HR 1.16 [95% CI 0.63–2.17], p = 0.63). CMV disease was not associated with a lower graft failure-free survival (HR 1.27 [95% CI 0.64–2.53], p = 0.50). Nevertheless, patients followed by the preemptive approach had an inferior graft failure-free survival after a median of 1.05 years of follow-up (HR 1.63 [95% CI 1.01–2.64], p = 0.044). The incidence of CMV disease in this cohort was low and not influenced by the preventive strategy used. However, patients on CMV prophylaxis were more likely to be free from graft failure.

In solid organ transplanted patients, annual influenza immunization is strongly recommended because of morbidity and mortality of influenza infections. In 2009, the rapid spread of a novel H1N1 influenza A virus led to the accelerated development of novel pandemic influenza vaccines. In Switzerland, the recipients received one dose of seasonal influenza and two doses of AS03-adjuvanted H1N1 vaccines. This situation provided a unique opportunity to analyze the influence of novel adjuvanted influenza vaccines on the production of de novoanti-HLA antibodies. We prospectively followed two independent cohorts including 92 and 59 kidney-transplanted patients, assessing their anti-HLA antibodies before, 6 weeks and 6 months after vaccination. Sixteen of 92 (17.3%) and 7 of 59 (11.9%) patients developed anti-HLA antibodies. These antibodies, detected using the single antigen beads technology, were mostly at low levels and included both donor-specific and non-donor-specific antibodies. In 2 of the 20 patients who were followed at 6 months, clinical events possibly related to de novoanti-HLA antibodies were observed. In conclusion, multiple doses of influenza vaccine may lead to the production of anti-HLA antibodies in a significant proportion of kidney transplant recipients. The long-term clinical significance of these results remains to be addressed.

In solid organ transplanted patients, annual influenza immunization is strongly recommended because of morbidity and mortality of influenza infections. In 2009, the rapid spread of a novel H1N1 influenza A virus led to the accelerated development of novel pandemic influenza vaccines. In Switzerland, the recipients received one dose of seasonal influenza and two doses of AS03‐adjuvanted H1N1 vaccines. This situation provided a unique opportunity to analyze the influence of novel adjuvanted influenza vaccines on the production of de novoanti‐HLA antibodies. We prospectively followed two independent cohorts including 92 and 59 kidney‐transplanted patients, assessing their anti‐HLA antibodies before, 6 weeks and 6 months after vaccination. Sixteen of 92 (17.3%) and 7 of 59 (11.9%) patients developed anti‐HLA antibodies. These antibodies, detected using the single antigen beads technology, were mostly at low levels and included both donor‐specific and non‐donor‐specific antibodies. In 2 of the 20 patients who were followed at 6 months, clinical events possibly related to de novoanti‐HLA antibodies were observed. In conclusion, multiple doses of influenza vaccine may lead to the production of anti‐HLA antibodies in a significant proportion of kidney transplant recipients. The long‐term clinical significance of these results remains to be addressed.

Visceral leishmaniasis (VL) due to Leishmania infantumis an endemic parasitic infection in the Mediterranean area. It most commonly affects immunosuppressed individuals, especially HIV patients and less frequently organ transplant recipients. Renal involvement seems to be frequent and is mostly associated with tubulointerstitial nephritis, as described in autopsy reports. In the 61 cases of renal transplant recipients with VL reported in the literature, renal dysfunction was noted at clinical presentation and was more frequently observed as a complication of antiparasitic therapy. However, no pathological analysis of the allograft lesions was reported. We present the case of a Swiss renal transplant recipient who developed VL after vacations in Spain and Tunisia, complicated by acute parasitic nephritis in the renal allograft 3 months after a well-conducted treatment of liposomal amphotericin B.

Visceral leishmaniasis (VL) due to Leishmania infantumis an endemic parasitic infection in the Mediterranean area. It most commonly affects immunosuppressed individuals, especially HIV patients and less frequently organ transplant recipients. Renal involvement seems to be frequent and is mostly associated with tubulointerstitial nephritis, as described in autopsy reports. In the 61 cases of renal transplant recipients with VL reported in the literature, renal dysfunction was noted at clinical presentation and was more frequently observed as a complication of antiparasitic therapy. However, no pathological analysis of the allograft lesions was reported. We present the case of a Swiss renal transplant recipient who developed VL after vacations in Spain and Tunisia, complicated by acute parasitic nephritis in the renal allograft 3 months after a well‐conducted treatment of liposomal amphotericin B.

The las quorum-sensing system of Pseudomonas aeruginosa controls the expression of elastase and rhamnolipid. We report that starvation can select a mutant producing these virulence factors in spite of a lasR deletion. Expression of the autoinducer synthase gene rhlI was increased in this suppressor mutant, suggesting compensation by the rhl system. These data show that P. aeruginosa can restore elastase and rhamnolipid production in the absence of a functional las quorum-sensing system.

A rapid and sensitive assay for the detection of lipase activity is described. The method is based upon the increase in absorbance at 360 nm due to the formation of the 2,4-dinitrophenolate anion during the enzymatic hydrolysis of 2,4-dinitrophenyl butyrate. The substrate is used in an emulsified form. Using a diode array spectrophotometer with internal referencing a correction can be made for absorbance changes due to clearance of the emulsion during hydrolysis. The small reaction volume and the high extinction coefficient of the product makes the method applicable for detection of both low substrate and low enzyme concentration.Four lipases were tested: lipase from porcine pancreas, Candida cylindracea, Pseudomonas sp. and Aspergillus niger. All enzymes are readily able to catalyse the hydrolysis of 2,4-dinitrophenyl butyrate.

To investigate the identity of Ins(1,4,5)P3-sensitive intracellular Ca2+ stores in myeloid cells, we have developed a method that yields subcellular fractions highly enriched in Ins(1,4,5)P3 binding. HL-60 cells were disrupted by nitrogen cavitation, and subcellular fractions were obtained by differential centrifugation, followed by Percoll- and sucrose-density-gradient separations. A subcellular fraction enriched 26-fold in Ins(1,4,5)P3-binding sites was obtained. This fraction showed no enrichment in plasma-membrane markers and only a comparatively moderate enrichment (7-fold) in endoplasmic-reticulum markers. The ratio between specific enrichment of Ins(1,4,5)P3 binding and endoplasmic-reticulum markers in the different fractions varied over 50-fold, from less than 0.1 to greater than 5. The purified Ins(1,4,5)P3-binding fraction was enriched to a similar extent (27-fold) in the putative intravesicular Ca(2+)-storage protein calreticulin. Our results favour the concept of a distinct Ins(1,4,5)P3-binding, calreticulin-containing compartment (i.e. the calciosome) in HL-60 cells.