View clinical trials related to Varicella Zoster Virus Infection.
Filter by:Kidney transplant recipients are at increased risk of infections, including Varicella-zoster virus (VZV) infections. Vaccination against VZV is routinely offered to all kidney transplant recipients and candidates in Denmark. In this exploratory observational study, the VZV specific immune response in kidney transplant candidates and recipients will be characterized at different time points in relation to transplantation, vaccination and infections. More knowledge on the immune reaction to transplantation, VZV vaccination and VZV infections may provide improved strategies for prevention and treatment of VZV infections in kidney transplant candidates and recipients.
Liver transplantation is the only curative treatment of end-stage liver disease, and every year, around 60 patients undergo liver transplantation in Denmark. Immunosuppressive therapy is necessary to avoid rejection of the transplanted organ. Over 90% of adults have been infected with at least one herpesvirus, and it is characteristic for herpesviruses that after a first-time infection, the virus remains dormant in the body and may reactivate, particularly if the host is immunosuppressed. An effective immune response against reactivation depends highly on T cells, but T cells are suppressed by immunosuppressive drugs given to organ transplant recipients. Infections caused by herpesviruses are therefore very common in organ transplant recipients, and particularly two herpesviruses, cytomegalovirus (CMV) and varicella-zoster virus (VZV) pose challenges after transplantation. CMV causes significant morbidity in transplant recipients, contributes to increased mortality and may contribute to loss of the transplanted organ. CMV infections occur in around 40% of liver transplant recipients within a year of transplantation. VZV causes chickenpox at first-time infection and shingles at reactivation. VZV is the second-most common infection in transplant recipients and occurs in around 9% of liver transplant recipients each year. Organ transplant recipients are at higher risk for disseminated disease with complications compared to immunocompetent persons. A limited number of drugs exist that reduce the risk of and treat CMV infection, but they may cause significant adverse events, and drug resistance is emerging. To avoid CMV infection, some liver transplant recipients receive prophylactic therapy, but due to toxicity, new treatment modalities are warranted. This requires knowledge about herpesvirus specific T cell function in liver transplant recipients, which currently is limited. The aim of this study is to provide an in-depth description of the protective immune response and immunological risk factors for CMV and VZV infections in liver transplant recipients and to identify patients at high risk in order to provide a platform for future treatment modalities against CMV and VZV infections in liver transplant recipients.
- Herpesvirus infections may be severe in immunocompromised patients, with a high risk of complications and mortality. - Recipients of hematopoietic stem cell transplant (HSCT) or patients receiving high-intensity chemotherapy for hematological malignancies are the most vulnerable individuals. - Although the worldwide prevalence of herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV), antiviral prophylaxis in seropositive HSCT recipients has significantly reduced the rate of infection. - Acyclovir (ACV) is the first-choice drug for the prophylaxis or the therapy of that kind of infection. - Since the beginning, ACV has demonstrated to be characterized by a large interpatient variability, especially in children. - Therefore, therapeutic drug monitoring and pharmacokinetic studies may help in optimizing drug in children with malignancies.
To evaluate the effect of intramuscular RZV vaccine on VZV-specific skin TRM and circulating T-cells
Among patients with thunderclap headache who were admitted to the four participating hospitals, who has diffuse segmental vasoconstriction on CT angiography or MR angiography will be eligible for the study. Participants who meet the definition of RCVS will be enrolled as the case-patients and others will be enrolled as control-patients. The RCVS group will be defined when two or more neurologists agree by the clinical features and angiographic findings. The result of tests for varicella zoster virus titer will not be opened to neurologists until the end of the study. For case and control patients, tests for varicella zoster virus infection are (1) Pre-existing virological markers (ex. VZV-IgG, IgM, and VZV PCR in CSF or Skin lesion if present) (2) VZV-specific cell mediated immune response (CMI) at the time of admission and one month later (3) VZV in blood measured by quantitative test of viral load with real-time PCR and digital PCR for latent viral load (4) Quantitative test of viral load with real-time PCR in saliva at time of admission and one month later. Reactivation or infection of VZV of patients with RCVS and controls will be compared.