Cytomegalovirus infection in pediatric patients with hepatoblastoma after liver transplantation

Imbalances of Th1/Th2 and Tc1/Tc2 are Associated With Active Cytomegalovirus Infection in Infant Liver Transplant Recipients

BACKGROUND

Because cytomegalovirus (CMV) infection is one of the most common complications following liver transplantation (LT), it is important to analyze the impact of CMV infection on the LT-associated changes in T cells polarization. This study aimed to investigate T helper (Th) and T cytotoxic (Tc) cells polarization and their correlation in infant LT recipients with active CMV infection.

METHODS

Twenty infant LT recipients with active CMV infection (the CMV group) and 20 recipients without CMV infection (the stable group) were enrolled. The percentages of Th1, Th2, Tc1, and Tc2 cells were detected by flow cytometry after intracellular staining for cytokines (IFN-γ and IL-10, respectively) in peripheral blood. The correlation between Th and Tc cells was analyzed by Pearson correlation coefficient.

RESULTS

The percentages of Th1 and Tc1 cells were significantly decreased, whereas the percentages of Tc2 cells were significantly increased in CMV group compared with the stable group, along with significant reduction of Th1/Th2 and Tc1/Tc2 ratios (P < .01). The percentages of Th1 cells were positively correlated with Tc1 cells (P < .01). A higher Th1/Th2 and Tc1/Tc2 ratios were showed in the CMV group after antiviral therapy than those in the CMV group before therapy (P < .01).

CONCLUSIONS

Our findings show an imbalanced Th1/Th2 and Tc1/Tc2 immunity in infant LT recipients with active CMV infection, which were involved in the pathogenesis of CMV infection.

Cytomegalovirus infection in liver-transplanted children

Cytomegalovirus (CMV) infection is a common complication of liver trans-plantation in children. The CMV serostatus of recipients and donors is the primary risk factor, and prophylaxis or pre-emptive strategies are recommended for high-risk patients. Graft rejection, coinfection and Epstein-Bar virus reactivation, which can lead to post-transplant lymphoproliferative disease, are indirect effects of CMV infection. Assessment of CMV infection viral load should be routinely performed upon clinical suspicion. However, tissue-invasive CMV disease is not associated with CMV viraemia and requires confirmation by tissue pathology. Oral valganciclovir and intravenous ganciclovir are equivalent treatments, and the duration of treatment depends on factors including CMV viral load, tissue pathology, and clinical response. Risk stratification by donor and recipient status prior to transplantation and post-transplantation antiviral prophylaxis or pre-emptive therapy are recommended. Adult guidelines have been established but additional study of the effectiveness of the preventive guidelines in children is needed. This review summarizes the burden, risk factors, clinical manifestations, laboratory evaluation, treatment, and prevention of CMV infection in children after liver transplantation.