Is cytomegalovirus viraemia a useful tool in managing CMV disease?

HIV related cytomegalovirus (CMV) disease results from reactivation of latent infection when the CD4 count falls below 100 cells ×10/l. Before the introduction of highly active antiretroviral therapy (HAART) up to 40% of HIV infected patients developed CMV disease, predominantly retinitis. Early diagnosis of retinitis may result in a better response to therapy and reduced loss of vision. As retinitis is often asymptomatic in the early stages, other methods of identifying individuals at risk are required. CMV viraemia precedes disease so the detection of CMV viraemia identifies individuals at highest risk. Cell culture based methods of detection have now been superseded by polymerase chain reaction (PCR) and pp65 antigenaemia assays. The application of quantitative techniques has shown that elevated CMV load increases the risk of CMV disease in congenital infection and following renal, liver, and bone marrow transplantation.