Monitoring for HHV-6 infection after renal transplantation: evaluation of risk factors for sustained viral replication

Human Cytomegalovirus and Human Herpesvirus-6 and Wilms Tumor: Is There a Link?

Background: Identifying etiologic factors contributing to Wilms tumor (WT) is necessary for its prevention and treatment. Oncogenic viruses cause nearly 20% of all human cancers. Although trials on preventing virus-caused cancers are complex and difficult, but they are not impossible to conduct. Human Cytomegalovirus (HCMV) and human herpes virus-6 (HHV6) can cause different types of cancers. Objectives: The current study aimed to investigate whether HCMV and HHV6-DNA are present in patients with WT. This is the first study of this kind in Iran. Methods: This study was performed on patients with kidney disorders who were referring to Mofid Pediatrics Hospital, Tehran (Iran), during 2010-16. In total, 98 kidney samples (49 patients with WT and 49 normal kidneys (autopsy) and kidneys with benign noninfectious lesions) were investigated to identify HCMV and HHV6-DNA. Qualitative Polymerase Chain reaction (PCR) method and nested polymerase chain reaction (nested-PCR) technique were used to identify HCMV and HHV6, respectively. Results: No significant difference was found between WT patients and controls concerning the HCMV or HHV6. Conclusions: Based on the findings, it can be concluded that there is no association between these viruses and WT.

Impact assessment and investigation of factors associated with herpesviruses viremia in the first year of renal transplantation

The increased risk for opportunistic infections after a renal transplant requires monitoring of viral infections to avoid future complications. Our goal was to investigate the impact and factors associated with Epstein-Barr virus (EBV), human cytomegalovirus (HCMV) and human herpesvirus type 6 (HHV-6) viremia in renal transplant recipients. Whole blood samples were collected monthly from 82 patients during the first semester and then quarterly up to 1 year after transplantation. EBV, HCMV, and HHV-6 were detected and quantified by TaqMan real-time polymerase chain reaction. The results showed that EBV and HCMV viremia were detected in 32 patients (39% each), while HHV-6 viremia in only 3 patients (3.7%). EBV was significantly associated with age (P = .050), thymoglobuline induction (P = .019), mTOR inhibitor-based therapy (P = .003), and female gender (P = .044). HCMV was significantly associated with basiliximab induction (P = .015), mycophenolate mofetil (MMF)-based therapy (P = .003) and allograft acute rejection (P = .033). Moreover, HCMV-disease was correlated with MMF-based therapy (P = .021) and female gender (P = .003). In conclusion, EBV and HCMV viremia were associated with different immunosuppressive induction and maintenance strategies. Additionally, higher HCMV viremia (> 10 ⁴ copies/mL) was related to acute allograft rejection.

Encephalitis caused by human herpesvirus-6B in pancreas-after-kidney transplantation

Human herpesvirus-6 (HHV-6) is a common pathogen among children, classically presenting with fever and rash that resolves without specific therapy. HHV-6 can be reactivated in the immunosuppressed patient. After bone marrow and solid organ transplantation, HHV-6 has been linked to various clinical syndromes, including undifferentiated febrile illness, encephalitis, myelitis, hepatitis, pneumonitis, and bone marrow suppression. However, HHV-6 encephalitis after pancreatic transplant has rarely been reported. Early diagnosis and treatment of HHV-6 encephalitis may be important for affected patients. We report the case of a 53-year-old pancreas-after-kidney transplant recipient who initially presented with high fever and confusion 3 weeks after operation. We managed to save the patient's life and preserve the pancreas graft function. We also review previously reported cases of HHV-6B encephalitis in solid organ transplant recipients.