The current burden of cytomegalovirus infection in kidney transplant recipients receiving no pharmacological prophylaxis / O fardo atual da infecção por citomegalovírus em receptores de transplante renal que não recebem profilaxia farmacológica

Abstract Cytomegalovirus (CMV) infection in kidney transplantation has changed its clinical spectrum, mostly due to the current and more effective immunosuppression. In the absence of preventive strategies it is associated with significant morbi-mortality. Objective: This study evaluated the incidence of CMV events and its effect on outcomes of kidney transplantation in recipients without pharmacological prophylaxis or targeted preemptive treatment. Results: The study cohort comprised 802 recipients of kidney transplants between 04/30/2014 and 04/30/2015. The majority received induction with anti-thymocyte globulin (81.5%), tacrolimus and prednisone in combination with either mycophenolate (46.3%) or azathioprine (53.7%). The overall incidence of CMV events was 42% (58.6% infection and 41.4% disease). Patients with CMV showed higher incidence of first treated acute rejection (19 vs. 11%, p = 0,001) compared with those without CMV but no differences in graft loss, death or loss to follow-up. The incidence of delayed graft function was higher (56% vs. 37%, p = 0.000) and the eGFR at 1 (41 ± 21 vs. 54 ± 28 ml/min, p = 0.000) and 12 months (50 ± 19 vs. 61 ± 29 ml/min, p = 0.000) were lower in patients with CMV. Recipients age (OR = 1.03), negative CMV serology (OR = 5.21) and use of mycophenolate (OR = 1.67) were associated with increased risk of CMV. Changes in immunosuppression was more often in patients with CMV (63% vs. 31%, p = 0.000). Conclusion: the incidence of CMV events was high and associated with higher incidence of acute rejection and changes in immunosuppression. Besides traditional risk factors, renal function at 1 month was independently associated with CMV infection.

Resumo A infecção por citomegalovírus (CMV) no transplante renal mudou seu espectro clínico, principalmente devido à atual e mais efetiva imunossupressão. Na ausência de estratégias preventivas, está associado a significativa morbimortalidade. Objetivo: este estudo avaliou a incidência de eventos de CMV e seu efeito nos desfechos do transplante renal em receptores sem profilaxia farmacológica ou tratamento preventivo direcionado. Resultados: A coorte do estudo envolveu 802 receptores de transplantes de rim entre 30/04/2014 e 30/04/2015. A maioria recebeu indução com globulina anti-timocitária (81,5%), tacrolimus e prednisona em combinação com micofenolato (46,3%) ou azatioprina (53,7%). A incidência global de eventos de CMV foi de 42% (58,6% de infecção e 41,4% de doença). Os pacientes com CMV apresentaram maior incidência de rejeição aguda do primeiro tratamento (19 vs. 11%, p = 0,001), em comparação com aqueles sem CMV, mas sem diferenças na perda de enxerto, morte ou perda de seguimento. A incidência de função retardada de enxerto foi maior (56% vs. 37%, p = 0,000) e a TFGe a 1 (41 ± 21 vs. 54 ± 28 ml/min, p = 0,000) e 12 meses (50 ± 19 vs. 61 ± 29 ml/min, p = 0.000) foram menores em pacientes com CMV. A idade dos receptores (OR = 1,03), a sorologia negativa para CMV (OR = 5,21) e o uso de micofenolato (OR = 1,67) foram associados ao aumento do risco de CMV. As alterações na imunossupressão foram mais frequentes em doentes com CMV (63% vs. 31%, p = 0,000). Conclusão: a incidência de eventos relacionados a CMV foi alta e associada a maior incidência de rejeição aguda e alterações na imunossupressão. Além dos fatores de risco tradicionais, a função renal com 1 mês foi associada de forma independente à infecção por CMV.

Targeted preemptive therapy according to perceived risk of CMV infection after kidney transplantation

ABSTRACT Background: The identification of the best strategy to manage cytomegalovirus infection is hampered by uncertainties regarding the risk/benefit ratios of universal prophylaxis versus preemptive therapy, the impact of indirect cytomegalovirus effects and the associated costs. This study investigated the efficacy and safety of targeted preemptive therapy according to perceived risk of cytomegalovirus infection after kidney transplantation. Methods: 144 adult kidney transplant recipients were enrolled in this 12-month study. None received cytomegalovirus pharmacological prophylaxis. Only high risk patients (positive donor/negative recipient (D+/R−), use of induction therapy with antithymocyte globulin, treatment of rejection) received preemptive therapy based on the result of pp65 antigenemia test. Low-risk patients with symptoms related to cytomegalovirus were screened for pp65 antigenemia and treatment initiated if confirmed cytomegalovirus disease. Blinded cytomegalovirus DNAemia was collected weekly during the first three months. Results: The incidence of cytomegalovirus infection was 34% and cytomegalovirus disease was 17%. The incidence was 25% in D+/R−, 69% in those receiving induction with rabbit antithymocite globulin (r-ATG), 46% in those treated for acute rejection, and 28% in low risk patients. By week 3 DNAemia was observed in 30% of patients who were not treated for cytomegalovirus infection/disease, and values ≥2.169 UI/mL showed 61% sensitivity and 85% specificity to detect cytomegalovirus disease (AUC = 0.849 ± 0.042, p < 0.001). Using multivariate analysis, only anti-thymocyte globulin induction was associated with cytomegalovirus infection/disease whereas only expanded donor criteria and renal function at 30 days were associated with renal function 12 months after transplantation. Conclusion: Targeted preemptive therapy in patients with perceived higher risk for cytomegalovirus infection/disease was effective in preventing severe clinical presentation, including tissue invasive and late cytomegalovirus infection. This strategy is associated with direct and indirect cost-savings.