The risk of late-onset cytomegalovirus (CMV) infection remains a concern in seronegative kidney and/or pancreas transplant recipients of seropositive organs despite the use of antiviral prophylaxis. The optimal duration of prophylaxis is unknown. We studied the cost effectiveness of 6-versus 3-mo prophylaxis with valganciclovir. A total of 222 seronegative recipients of seropositive kidney and/or pancreas transplants received valganciclovir prophylaxis for either 3 or 6 mo during two consecutive time periods. We assessed the incidence of CMV infection and disease 12 mo after completion of prophylaxis and performed cost-effectiveness analyses. The overall incidence of CMV infection and disease was 26.7% and 24.4% in the 3-mo group and 20.9% and 12.1% in the 6-mo group, respectively. Six-month prophylaxis was associated with a statistically significant reduction in risk for CMV disease (HR, 0.35; 95% CI, 0.17 to 0.72), but not infection (HR, 0.65; 95% CI, 0.37 to 1.14). Cost-effectiveness analyses showed that 6-mo prophylaxis combined with a one-time viremia determination at the end of the prophylaxis period incurred an incremental cost of $34,362 and $16,215 per case of infection and disease avoided, respectively, and $8,304 per one quality adjusted life-year gained. Sensitivity analyses supported the cost effectiveness of 6-mo prophylaxis over a wide range of valganciclovir and hospital costs, as well as variation in the incidence of CMV disease. In summary, 6-mo prophylaxis with valganciclovir combined with a one-time determination of viremia is cost effective in reducing CMV infection and disease in seronegative recipients of seropositive kidney and/or pancreas transplants.

PRM is a novel imaging tool for lung transplant recipients presenting with spirometric decline. Quantifying underlying small airway obstruction via PRM helps further stratify the risk of death in patients with diverse spirometric decline patterns.

Fibrotic diseases display mesenchymal cell (MC) activation with pathologic deposition of matrix proteins such as collagen.Here we investigate the role of mTOR complex 1 (mTORC1) and mTORC2 in regulating MC collagen expression, a hallmark of fibrotic disease. Relative to normal MCs (non-Fib MCs), MCs derived from fibrotic human lung allografts (Fib-MCs) demonstrated increased phosphoinositide-3kinase (PI3K) dependent activation of both mTORC1 and mTORC2, as measured by increased phosphorylation of S6K1 and 4E-BP1 (mTORC1 substrates) and AKT (an mTORC2 substrate). Dual ATP-competitive TORC1/2 inhibitor AZD8055, in contrast to allosteric mTORC1-specific inhibitor rapamycin, strongly inhibited 4E-BP1 phosphorylation and collagen I expression in Fib-MCs. In non-Fib MCs, increased mTORC1 signaling was shown to augment collagen I expression. mTORC1/4E-BP1 pathway was identified as an important driver of collagen I expression in FibMCs in experiments utilizing raptor gene silencing and overexpression of dominant-inhibitory 4E-BP1. Furthermore, siRNA-mediated knockdown of rictor, an mTORC2 partner protein, reduced mTORC1 substrate phosphorylation and collagen expression in Fib-, but not non-Fib MCs, revealing a dependence of mTORC1 signaling on mTORC2 function in activated MCs. Together these studies suggest a novel paradigm where fibrotic activation in MCs increases PI3K dependent mTORC1 and mTORC2 signaling and leads to increased collagen I expression via the mTORC1-dependent 4E-BP1/ eIF4E pathway. These data provide rationale for targeting specific components of mTORC pathways in fibrotic states and underscore the need to further delineate mTORC2 signaling in activated cell states.Tissue fibrosis, marked by mesenchymal cell (MC) 2 infiltration and collagen deposition, continues to be a major cause of organ failure and death both before and after transplantation. Within five years of lung transplantation, 50% of the recipients demonstrate a decline in their lung function termed bronchiolitis obliterans syndrome which arises from progressive airway fibrosis (1, 2). Histologic samples reveal pathologic collagen matrix deposition with interspersed MCs (3). Relentless fibroproliferation is the hallmark of chronic allograft failure across all solid organ transplants, and targeting mechanisms of MC activation and matrix deposition is key to improving long term outcomes.Mammalian target of rapamycin (mTOR), an evolutionarily conserved serine/threonine protein kinase, links multiple upstream signaling cascades to downstream translational activation (4, 5). mTOR forms the catalytic core of two distinct complexes known as mTOR complex 1 (mTORC1) and mTORC2, which are defined by their partner proteins raptor and rictor, respectively (6). mTORC1 promotes cap-dependent mRNA translation via phosphorylation of its effectors S6K1 (ribosomal protein S6 Kinase 1) and 4E-BP1 (eukaryotic initiation factor 4E-binding protein1) (7-11). mTORC2 functions as the major kinase for AKT (12). Constitutive activation of the mTORC1 pathway and incre...

Invasive fungal infection remains a serious postoperative complication in lung transplant recipients and is associated with significant morbidity and mortality. Although most lung transplant centers use antifungal prophylaxis, consensus on the strategy, choice of antifungal agent(s), route of administration, and duration of prophylaxis have not been established. This review provides an overview of the epidemiology and risk factors for common fungal infections seen in lung transplant recipients, evaluates the clinical efficacy and toxicity of the various antifungal agents used to prevent infection, and offers recommendations and opportunities for future research. Currently available data evaluating the efficacy of antifungal prophylaxis strategies is limited by a lack of prospective, randomized clinical trial data and variability in patient populations, prophylactic and immunosuppressive strategies, dosing, durations of use of antifungal agents, and definitions of invasive infection. There is controversy regarding significant risk factors for invasive fungal infection, which has limited the development and validation of targeted prophylactic strategies. Inhaled formulations of amphotericin B remain the most widely studied option for universal prophylaxis and have been shown to be effective in reducing the incidence of invasive Aspergillosis as compared with no prophylaxis. Concern over early postoperative extrapulmonary infection may suggest a benefit of initial prophylaxis with a systemic azole. Long-term use of systemic antifungals is not optimal due to emerging evidence of long-term toxicities. Multicenter, randomized trials are needed to ascertain the optimal prophylactic strategy in lung transplant recipients. New agents and delivery mechanisms may offer additional opportunities for comparative research.

Background Abnormal glucose metabolism (AGM) and metabolic syndrome (MS) are individually associated with a poor cardiovascular outcome in kidney transplant recipients. We prospectively studied the relationship between AGM and MS in non-diabetic kidney transplant recipients early after transplantation. Methods A total of 203 de novo kidney transplant recipients underwent standard 2-hr glucose tolerance test 10 weeks after transplantation. Demographic and clinical characteristics were collected. AGM was defined as impaired fasting glucose, impaired glucose tolerance, and new onset diabetes after transplant according to the WHO criteria, and MS was defined according to the National Cholesterol Education Expert Panel criteria. Results Overall, 97 patients (47.8%) met the diagnosis of AGM and 98 patients (48.3%) met the criteria of MS. AGM and MS are highly associated (χ2, P<0.001). Fasting plasma glucose levels before the transplant are independent predictors common for AGM and MS. Age predicts AGM with and without MS, whereas body mass index before transplant predicts MS. Patients with impaired glucose tolerance and new-onset diabetes after transplant displayed significant worsening of their fasting plasma glucose levels during the 10-week observational period. MS and the components of MS, but not AGM, were associated with reduced transplant renal function (P=0.002). Conclusion The early screening of AGM and MS should be emphasized, and the role of early therapeutic interventions aimed at both conditions explored. The long-term follow-up of these patients will yield more insight on the significance of such findings.