Infections due to alphaherpesviruses in early post-transplant period after allogeneic haematopoietic stem cell transplantation: Results of a 5-year survey.

BACKGROUND: Infections caused by human α-herpesviruses usually have a benign course with recurrencies. However, they may become dangerous in immunocompromised hosts. In this case, molecular methods constitute a reliable diagnostic tool enabling rapid assessment of the efficacy of antiviral treatment strategies.

OBJECTIVES: We estimated the frequency of alphaherpesviral DNAemia and the viral load during early post-transplantation period after alloHSCT; we also analyzed association of the DNAemia and chosen parameters of the patients.

STUDY DESIGN: A cohort of 190 alloHSCT recipients from two hospitals in Warsaw, Poland, was examined weekly during 100-day early post-transplantation period using quantitative real time PCR assays. A total of 2475 sera samples were evaluated for the presence of α-herpesviral DNA in patients, of whom 117 (62%) received unrelated grafts, while the remaining 73 (38%) received grafts from sibling donors. All patients received standard antiviral prophylaxis with acyclovir. In the examined group, anti-HSV-1, anti-HSV-2 and anti-VZV IgGs were examined prior to transplantation, RESULTS: Within the study period, DNA of α-herpesviruses was detected in 44 patients (23.2%). Most patients tested positive for HSV-1 DNA (43 patients, 22.6%), single patient for HSV-2, and no patient positive for VZV. Clinical symptoms such as pneumonia, skin changes, elevated levels of aminotransferases were observed in five patients, four of these patients presented symptoms of GvHD at the same time. (2,6%). Statistics shows that GvHD (P<0.001) and matched unrelated donor as a source of HSCT (P=0.048) are associated with the development of HSV-1 DNAemia.

CONCLUSIONS: Although our data demonstrate frequent reactivation of HSV-1 in the early post-transplant period, the rate of symptomatic infections was low. We did not find association between HSV-1 viremia and mortality, but significant association with GvHD and donor source was observed.