These guidelines from the American Society of Transplantation Infectious Diseases Community of Practice update the epidemiology and management of human papillomavirus (HPV) infections in organ ...transplant recipients. HPV is one of the most common sexually transmitted infections and is associated with cancers of the anogenital region. Increasing evidence suggests an association with head and neck cancers as well. Solid organ transplant recipients have a higher risk of HPV infection than the general population. Infection manifests as premalignant lesions, warts, or cancer of the cervix, penis, vulva, scrotum, and anal canal. Most are asymptomatic initially, so diagnosis can be difficult without screening. A vaccine is available though not effective in preventing all cancer‐causing strains. Organ transplant recipients should be screened for HPV‐associated cancers and appropriate therapy initiated in a timely manner. Further studies are warranted to delineate the most effective screening methods and therapeutic modalities, including whether changes in immunosuppression are effective in attenuating disease.
This editorial comments on Larsen et al's (page 156) important population‐based study showing that renal transplant recipients have a higher incidence of HPV‐associated anogenital warts compared to ...the general population, and makes a case for more diligent screening and vaccination in transplant patients.
T cell immunity is essential for the control of cytomegalovirus (CMV) infection after transplantation. We evaluated a CMV‐specific peptide‐based enzyme‐linked immunosorbent spot (ELISPOT) assay to ...determine whether assay results could predict subsequent CMV events. Adult kidney transplant recipients at 43 centers underwent ELISPOT testing to enumerate interferon gamma (IFN‐γ) binding spot‐forming units (sfu) after stimulation of cells with an overlapping peptide pool of CMV phosphoprotein 65 (pp65) and immediate early‐1 (IE‐1) protein at the end of antiviral prophylaxis (EOP) and various time points thereafter. The primary outcome was a CMV event in the first posttransplant year. In 583 kidney transplant recipients (260 seropositive donor D+/seronegative recipient R− and 277 R+), CMV events occurred in 44 of 368 eligible patients (11.8%) at a median of 227 days (range 92‐360) posttransplant. A cutoff value of >40 sfu/2.5 × 105 cells for either IE‐1 or pp65 was derived as a threshold for positivity, with a negative predictive value of >97% for CMV events. CMV events were significantly lower in assay positive vs assay negative patients (3.0% vs 19.5%, P < .0001 for pp65). Time to CMV event post‐EOP was significantly greater in those with sfu >40 at EOP (P < .0001). In this large, multicenter trial of kidney transplant recipients, we show that an assessment of CMV‐specific immunity using a novel ELISPOT assay is able to predict protection from CMV infection.
In a multicenter study of kidney transplant recipients, the authors show that measuring CMV‐specific T cell immunity using a novel ELISPOT assay predicts protection from CMV infection in CMV‐seropositive patients.
Human papillomavirus (HPV) is a common infection in kidney transplant recipients. HPV causes cervical, anal, vulvar, vaginal, penile and head and neck cancers. Kidney transplant recipients have a ...disproportionate burden of disease given prolonged immunosuppression. Given the long pre-invasive state of precancer lesions such as cervical intraepithelial neoplasia (CIN) and anal intraepithelial neoplasia (AIN) most HPV-cancers are preventable with screening and targeted treatment of disease. Pre-transplant vaccination of age-eligible kidney transplant recipients is otherwise ideal.
This work proposes a cross-layered caching strategy for parameter estimation in wireless sensor networks (WSNs). Here, sensors first gather information about common parameters of interest and then ...forward the information to an edge server for final inference. The collaborative nature of this application enables the caching of linearly compressed information across sensors rather than individual observations. By assuming that the parameters are correlated over time, the estimation quality at the edge server can be improved by combining both present and past information, where the latter can be obtained from cached data. The data caching and accessing strategies are jointly designed to minimize the expected mean-squared-error (MSE) of the requested parameter estimates. We first consider a single-cache single-server scenario under ideal accessing assumptions and propose a greedy one-step-ahead (OSA) caching strategy that determines the optimal linear combination of observations to cache by minimizing the expected MSE of the requested parameter estimate in the next time slot. We adopt an alternating optimization approach where the combining coefficients at the cache and the linear estimator at the server are optimized in turn until convergence. Then, the proposed OSA caching strategy is extended to the multi-cache multi-server scenario with constraints on the accessing costs at both the caches and the edge servers. The alternating optimization subproblems in this case are non-convex due to the additional access constraints and, thus, are solved by adopting a successive convex approximation (SCA) procedure. Numerical simulations are provided to demonstrate the effectiveness of the proposed caching strategies.
Organ procurement organizations (OPO) test potential deceased organ donors for infectious diseases required by policy, but many also perform testing for additional infections. The current state of ...donor testing in the United States is unknown. We sent an IRB approved survey to all 57 U.S. OPOs using REDCap. Descriptive statistics were performed. From the 57 OPOs, we received 46 (80.7%) unique responses with all 11 United Network of Organ Sharing regions represented. Forty of 46 (87%) OPO respondents consulted an Infectious Diseases physician when needed. Eighteen of 46 (39%) tested for West Nile virus (WNV) and 17 of 18 (94%) tested year‐round. Eleven of 46 (23.9%) tested for Strongyloides infection while 17 of 46 (37%) tested for Chagas disease. All OPOs performed prospective nucleic acid testing (NAT) for HIV, hepatitis B and hepatitis C on all donors. OPO testing of additional infections has increased since prior surveys but remains variable. Standardization of organ donor infectious diseases evaluation should be considered.
Responses from organ procurement organizations to a survey on testing of all deceased organ donors for infectious diseases shows that less than 40% tested for West Nile virus and Chagas disease, 24% tested for Strongyloides infection, while 100% tested for HIV, hepatitis B, and hepatitis C.
The coronavirus disease 2019 (COVID‐19) pandemic caused by SARS coronavirus 2 (SARS‐CoV‐2) has caused significant morbidity and mortality for patients and stressed healthcare systems worldwide. The ...clinical features, disease course, and serologic response of COVID‐19 among immunosuppressed patients such as solid organ transplant (SOT) recipients, who are at presumed risk for more severe disease, are not well characterized. We describe our institutional experience with COVID‐19 among 10 SOT patients, including the clinical presentation, treatment modalities, and outcomes of 7 renal transplant recipients, 1 liver transplant recipient, 1 heart transplant recipient, and 1 lung transplant recipient. In addition, we report the serologic response in SOT recipients, documenting a positive IgG response in all 7 hospitalized patients. We also review the existing literature on COVID‐19 in SOT recipients to consolidate the current knowledge on COVID‐19 in the SOT population for the transplant community.
This study reports the clinical course of 10 solid organ transplant recipients with COVID‐19, including positive IgG serologic responses among all hospitalized patients.
This work examines the use of image surveillance UAVs for relay communication between ground users and a remote base station (BS). UAVs take aerial images of the surveillance region and forward them ...to the BS while serving the uplink transmission demands of ground users. We first consider the single-UAV scenario and jointly determine the UAV's trajectory, task assignment, user association, and rate allocation by maximizing the sum-log-throughput of the users subject to constraints on the surveillance coverage, image transmission requirements, and relay capacity. The resulting mixed-integer nonlinear programming problem is solved by an inexact block coordinate descent (BCD) algorithm where we inherit ideas from the exact penalty method for mathematical programming with equilibrium constraints to relax the integer constraints and the successive convex approximation approach to address the non-convexity of the trajectory optimization problem. Then, we extend the proposed framework to the case with multiple UAVs that are dispatched to cover a wide surveillance region. The UAVs may complete both relay and surveillance tasks more efficiently through cooperation and proper task allocation for UAVs. A similar BCD algorithm is adopted to solve the problem. Numerical simulations are provided to demonstrate the effectiveness of the proposed scheme over several baseline methods.
Objectives
Host iron availability is fundamental to mucormycosis pathogenesis. The combination of liposomal amphotericin B (LAmB) and deferasirox iron chelation therapy synergistically improved ...survival in diabetic mice with mucormycosis. To determine the safety of combination deferasirox plus LAmB therapy for mucormycosis, a multicentred, placebo-controlled, double-blinded clinical trial was conducted.
Methods
Twenty patients with proven or probable mucormycosis were randomized to receive treatment with LAmB plus deferasirox (20 mg/kg/day for 14 days) or LAmB plus placebo (NCT00419770, clinicaltrials.gov). The primary analyses were for safety and exploratory efficacy.
Results
Patients in the deferasirox arm (n = 11) were more likely than those in the placebo arm (n = 9) to have active malignancy, neutropenia and corticosteroid therapy, and were less likely to receive concurrent non-study antifungal therapy. Reported adverse events and serious adverse events were similar between the groups. However, death was more frequent in the deferasirox than in the placebo arm at 30 days (45% versus 11%, P = 0.1) and 90 days (82% versus 22%, P = 0.01). Global success (alive, clinically stable, radiographically improved) for the deferasirox arm versus the placebo arm at 30 and 90 days, respectively, was 18% (2/11) versus 67% (6/9) (P = 0.06) and 18% (2/11) versus 56% (5/9) (P = 0.2).
Conclusions
Patients with mucormycosis treated with deferasirox had a higher mortality rate at 90 days. Population imbalances in this small Phase II study make generalizable conclusions difficult. Nevertheless, these data do not support a role for initial, adjunctive deferasirox therapy for mucormycosis.
Recent advances in wireless power transfer (WPT) technology enable over-the-air charging of passive sensor devices and allow sensors to be active on demand without concern of their battery lifetime. ...This work examines the beam pattern selection and charging power allocation problems for distributed estimation applications in wireless passive sensor networks (WPSNs) that employ WPT to replenish sensors. The charging operation consists of two-phases: an exploration phase and a replenishment-and-transmission phase. In the exploration phase, radio-frequency (RF) energy chargers first scan the network in turn using different beam patterns and sensors that harvest sufficient energy based on these beams emit pilot signals to enable channel estimation at the fusion center. In the replenishment-and-transmission phase, beam patterns and charging powers are first chosen based on the available channel state information (CSI) and then used to emit RF charging signals to replenish the sensors. The sensors utilize the harvested RF energy to make local observations of the underlying parameter of interest and transmit them to the fusion center, where the final estimate is computed. In this paper, the beam pattern selection and charging power allocation are first jointly optimized with the goal of minimizing the mean-square error (MSE) of the final estimate under perfect CSI. For tractability, an MSE upper bound is used as the objective function and the problem is solved efficiently using the block successive upper bound minimization (BSUM) method. The impact of the exploration threshold and duration on the MSE is then examined for the imperfect CSI case. Simulation results demonstrate the effectiveness of the proposed scheme.
PDF
