HHV-6 in liver transplantation : A literature review

Human herpesvirus 6 (HHV-6A and HHV-6B) can cause primary infection or reactivate from latency in liver transplant recipients, which can result in a variety of clinical syndromes, including fever, hepatitis, encephalitis and higher rates of graft dysfunction as well as indirect effects including increased risks of mortality, CMV disease, hepatitis C progression and greater fibrosis scores. Although HHV-6 infection is currently diagnosed by quantifying viral DNA in plasma or blood, biopsy to demonstrate histopathological effects of HHV-6 remains the gold standard for diagnosis of end-organ disease. HHV-6 reactivation may be restricted to the infected organ with no evidence of active infection in the blood. HHV-6 infections in liver transplant patients are mostly asymptomatic, but clinically significant tissue-invasive infections have been treated successfully with ganciclovir, foscarnet or cidofovir. Inherited chromosomally integrated HHV-6 (ciHHV-6), in either the recipient or the donor organ, may create confusion about systemic HHV-6 infection. Recipients with inherited ciHHV-6 may have an increased risk of opportunistic infection and graft rejection. This article reviews the current scientific data on the clinical effects, risk factors, pathogenesis, diagnosis and treatment of HHV-6 infections in liver transplant recipients.Peer reviewe

Cytomegalovirus Infection After Liver Transplantation

Key Points 1. Cytomegalovirus (CMV) is a common infection after liver transplantation and manifests as an asymptomatic infection or clinically as CMV syndrome (fever and myelosuppression) or tissue-invasive CMV disease. 2. The most common risk factor for CMV disease is donor positivity and recipient negativity for CMV, and severe impairment in immunity, especially with a pathogen-specific immune response, generally predisposes patients to CMV disease after transplantation. 3. The prevention of CMV disease after liver transplantation consists of preemptive therapy (antiviral therapy is administered only in the presence of a positive CMV polymerase chain reaction or pp65 antigenemia) or antiviral prophylaxis (an antiviral drug is administered to all patients at risk of CMV disease). 4. The treatment of CMV disease consists of intravenous ganciclovir (for severe disease) or oral valganciclovir (for mild to moderate CMV disease). Liver Transpl 16:S45-S53, 2010. copy; 2009 AASLD

Impact of human herpes virus 6 in liver transplantation

Human herpes virus 6 (HHV-6) infects > 95% of humans. Primary infection which occurs mostly during the first 2 years of life in the form of roseola infantum, non-specific febrile illness, or an asymptomatic illness, results in latency. Reactivation of latent HHV-6 is common after liver transplantation. Since the majority of human beings harbor the latent virus, HHV-6 infections after liver transplantation are most probably caused by endogenous reactivation or superinfection. In a minority of cases, primary HHV-6 infection may occur when an HHV-6-seronegative individual receives a liver allograft from an HHV-6-seropositive donor. The vast majority of HHV-6 infections after liver transplantation are asymptomatic. Only in a minority of cases, when HHV-6 causes a febrile illness associated with rash and myelosuppression, hepatitis, gastroenteritis, pneumonitis, and encephalitis after liver transplantation. In addition, HHV-6 has been implicated in a variety of indirect effects, such as allograft rejection and increased predisposition to and severity of other infections, including cytomegalovirus, hepatitis C virus, and opportunistic fungi. Because of the uncommon nature of the clinical illnesses directly attributed to HHV-6, there is currently no recommended HHV-6-specific approach prevention after liver transplantation. Asymptomatic HHV-6 infection does not require antiviral treatment, while treatment of established HHV-6 disease is treated with intravenous ganciclovir, foscarnet, or cidofovir and this should be complemented by a reduction in immunosuppression

COVID-19 and Solid Organ Transplantation: Role of Anti-SARS-Cov-2 Monoclonal Antibodies

PURPOSE OF REVIEW: Solid organ transplant recipients (SOTRs) are ideal candidates for early treatment or prevention of coronavirus disease 2019 (COVID-19) using anti-SARS-CoV-2 monoclonal antibodies because of multiple underlying medical conditions, chronic immune-suppression, sub-optimal immunogenic response to vaccination, and evolving epidemiological risks. In this article, we review pertinent challenges regarding the management of COVID-19 in SOTRs, describe the role of active and passive immunity in the treatment and prevention of COVID-19, and review real-world data regarding the use of anti-SARS-CoV-2 monoclonal antibodies in SOTRs. RECENT FINDINGS: The use of an anti-SARS-CoV-2 monoclonal antibody in high-risk solid organ transplant recipients is associated with a reduction in the risk of hospitalization, need for intensive care, and death related to COVID-19. Overall, the early experiences from a diverse population of solid organ transplant recipients who were treated with anti-spike monoclonal antibodies are encouraging with no reported acute graft injury, severe adverse events, or deaths related to COVID-19. SUMMARY: Anti-SARS-CoV-2 antibodies are currently authorized for treatment of mild-moderate COVID-19 and post-exposure prophylaxis, including in SOTRs. Potential future uses include pre-exposure prophylaxis in certain high-risk persons and synergistic use along with emerging oral treatment options. Successful timely administration of anti-SARS-CoV-2 monoclonal antibodies requires a multidisciplinary team approach, effective communication between patients and providers, awareness of circulating viral variants, acknowledgement of various biases affecting treatment, and close monitoring for efficacy and tolerability

Current concepts on cytomegalovirus infection after liver transplantation

Cytomegalovirus (CMV) is the most common viral pathogen that negatively impacts on the outcome of liver transplantation. CMV cause febrile illness often accompanied by bone marrow suppression, and in some cases, invades tissues including the transplanted allograft. In addition, CMV has been significantly associated with an increased predisposition to allograft rejection, accelerated hepatitis C recurrence, and other opportunistic infections, as well as reduced overall patient and allograft survival. To negate the adverse effects of CMV on outcome, its prevention, whether through antiviral prophylaxis or preemptive therapy, is regarded as an essential component to the medical management of liver transplant patients. Two recent guidelines have suggested that antiviral prophylaxis or preemptive therapy are similarly effective in preventing CMV disease in modest-risk CMV-seropositive liver transplant recipients, while antiviral prophylaxis is the preferred strategy over preemptive therapy for the prevention of CMV disease in high-risk recipients [CMV-seronegative recipients of liver allografts from CMV-seropositive donors (D+/R-)]. However, antiviral prophylaxis has only delayed the onset of CMV disease in many CMV D+/R- liver transplant recipients, and at least in one study, such occurrence of late-onset primary CMV disease was significantly associated with increased mortality after liver transplantation. Therefore, optimized strategies for prevention are needed, and aggressive treatment of CMV infection and disease should be pursued. The standard treatment of CMV disease consists of intravenous ganciclovir or oral valganciclovir, and if feasible, one should also reduce the degree of immunosuppression. In one recent controlled clinical trial, valganciclovir was found to be as effective and safe as intravenous ganciclovir for the treatment of mild to moderate CMV disease in solid organ (including liver) transplant recipients. In this article, the authors review the current state and the future perspectives of prevention and treatment of CMV disease after liver transplantation

Infections in liver transplant recipients

Liver transplantation is a standard life-saving procedure for the treatment of many end-stage liver diseases. The success of this procedure may be limited by infectious complications. In this article, we review the contemporary state of infectious complications during the post-operative period, with particular emphasis on those that occur most commonly during the first 6 mo after liver transplantation. Bacteria, and less commonly Candida infections, remain the predominant pathogens during the immediate post-operative period, especially during the first month, and infections caused by drug-resistant strains are emerging. Infections caused by cytomegalovirus and Aspergillus sp. present clinically during the “opportunistic” period characterized by intense immunosuppression. As newer potent immunosuppressive therapies with the major aim of reducing allograft rejection are developed, one potential adverse effect is an increase in certain infections. Hence, it is essential for liver transplant centers to have an effective approach to prevention that is based on predicted infection risk, local antimicrobial resistance patterns, and surveillance. A better understanding of the common and most important infectious complications is anticipated to lead to improvements in quality of life and survival of liver transplant recipients

Non-tuberculous mycobacterial infections in solid organ transplant recipients: An update

Non-tuberculous mycobacteria are ubiquitous environmental organisms that are now increasingly recognized as important causes of clinical disease in solid organ transplant recipients. Risk factors of non-tuberculous mycobacteria infection are severe immunologic defects and structural abnormalities. Lung transplant recipients are at higher risk for non-tuberculous mycobacterial disease compared to recipients of other solid organs. The clinical presentation could be skin and soft tissue infection, osteoarticular disease, pleuropulmonary infection, bloodstream (including catheter-associated) infection, lymphadenitis, and disseminated or multi-organ disease. Management of non-tuberculous mycobacteria infection is complex due to the prolonged treatment course with multi-drug regimens that are anticipated to interact with immunosuppressive medications. This review article provides an update on infections due to non-tuberculous mycobacteria after solid organ transplantation, and discusses the epidemiology, risk factors, clinical presentation, and management. Keywords: Mycobacteria, Transplantation, Pneumonia, Lung transplantation, Drug interaction