Clinic Laboratory Surveillance of infection by Human Herpesvírus 6 (HHV-6) and Human Herpesvírus 7 (HHV-7) and Co-infection with Human Citomegalovírus (HCMV) after Liver Transplantation

Abstract

Human herpesviruses HHV-6 and HHV-7 after primary infection remain latent in the body and can reactivate after immunosuppression. Purpose: The laboratory surveillance of HHV-6 and HHV-7 and the evaluation of co-infection with HCMV human cytomegalovirus in post-liver transplantation were carried out through antigenemia, serology and N-PCR techniques. Methods: Samples from 32 patients, median age of 47 (18-66) years old, being 20 (62.5%) male and 12 (37.5%) were female. Biological monitoring began before transplant, weekly from 1st to 2nd months, biweekly in the 3rd month, and monthly from the 4th month to the 6th months. Extraction of lymphocytes was performed for the HHV-6 and HHV-7 antigenemia technique. Detection of IgM antibodies HHV-6 was done by the ELISA test. N-PCR and serology was applied for HCMV, HHV-6 and HHV-7. Results: With these methods, the detection of HHV-6 IgM was positive along the pre-transplant period in 15.6% of patients, 25% after the fourth week, 40.6% after the 12th week, and 46.9% at 24 weeks after the transplant. The HCMV, HHV-6 and HHV-7 antigenemias were positive in 46.9%, 62.5% and 46.8% respectively, N-PCR was positive for HCMV and HHV-6 in 81% of cases, and for HHV-7 in 46.8%. It was found that 50% of patients studied had HCMV disease. The disease caused by HHV-6 was present in 46.8% of patients and 15.6% for HHV-7. Concomitant disease was observed in patients with HCMV and HHV-6 in 21.9% and 15.6% of patients with HHV-6 and HHV-7. The disease caused by betaherpesvirus was more frequently detected around the fifth week. The HHV-6 and HHV-7 illness episodes preceded the onset of HCMV disease. Conclusion: This study confirmed the relevance of HCMV, HHV-6 and HHV-7 infections and the importance of using monitoring techniques for early detection of these agents allowing the use of a preemptive treatment with reduced risk to the disease.