Pre-emptive treatment with antiviral agents reduces the risk of cytomegalovirus disease when compared to placebo or usual care

Cytomegalovirus (CMV) is the most common virus pathogen in solid organ transplant recipients (kidney, heart, liver, lung and pancreas) and is the major cause of morbidity and mortality during the first six months after transplantation. CMV disease is characterised by fever, leucopenia (very low white blood cells) and thrombocytopenia (very low platelet numbers) with or without specific organ dysfunction. Two main strategies to prevent CMV disease have been adopted: prophylaxis of organ recipients with antiviral agents, or pre-emptive treatment of solid organ recipients, who develop evidence of CMV infection during routine screening. This review looked at the benefits and harms of pre-emptive treatment with antiviral agents in preventing CMV disease in solid organ transplant recipients. Ten trials (476 participants) were identified comparing pre-emptive treatment with placebo or usual care, pre-emptive treatment with antiviral prophylaxis and oral versus intravenous treatment. Compared with placebo or usual care, pre-emptive treatment significantly reduced the risk of CMV disease but not acute rejection or all-cause mortality. Pre-emptive therapy versus prophylaxis and oral versus intravenous pre-emptive treatment showed no significant difference in the risks of CMV disease or all-cause mortality. More trials comparing pre-emptive treatment with antiviral prophylaxis are needed.