Comparison of Quantitative Cytomegalovirus (CMV) PCR in Plasma and CMV Antigenemia Assay: Clinical Utility of the Prototype AMPLICOR CMV MONITOR Test in Transplant Recipients

Abstract

The correlation between the prototype AMPLICOR CMV MONITOR test (Roche Molecular Systems), a quantitative PCR assay, and the cytomegalovirus (CMV) pp65 antigenemia assay was evaluated in transplant recipients. Sequential blood specimens were collected on 29 patients (491 specimens), the leukocyte fraction was tested by CMV antigenemia, and quantitative PCR was performed on plasma specimens. None of the 15 patients (242 specimens) who were antigenemia negative were positive for CMV DNA by PCR, and none of these patients developed active CMV disease. There were 14 antigenemia-positive patients, 8 of whom developed active CMV disease. In all patients, there was a good association between the antigenemia and PCR assays. Ganciclovir-resistant virus was isolated from three patients with active CMV disease. These three patients had persistently elevated levels of antigenemia and CMV DNA by PCR when resistance to ganciclovir developed. This standardized, quantitative CMV PCR assay on plasma has clinical utility for the diagnosis of active disease and in monitoring the response to antiviral therapy in transplant recipients.

Cytomegalovirus in Solid Organ Transplantation

“…Antigenemia has higher sensitivity than culture, and is comparable to NAT by polymerase chain reaction (PCR; Ref. ). Depending on the number of CMV‐infected cells, one can estimate the magnitude of viral replication.…”

Cytomegalovirus in Solid Organ Transplant Recipients

“…The pp65 antigenemia assay is a semi‐quantitative fluorescent assay based on detection of infected cells in peripheral blood. This assay has far higher sensitivity and specificity than culture‐based methods (8), and is comparable in sensitivity to CMV PCR (see further) (9). Though not fully quantitative, it can provide an estimate of the magnitude of viral load from the number of infected cells.…”

“…Occasionally patients with tissue invasive disease (especially gastrointestinal or retinal disease) will have undetectable blood viral loads. Both the pp65 antigenemia assay and quantitative CMV viral load testing can be utilized in preemptive protocols, for diagnosis of CMV disease, and to guide management of CMV disease (8–12). A lack of standardization between different centers is a major problem with all assays.…”

CMV infection, diagnosis and antiviral strategies after liver transplantation

“…The first commercial quantitative plasma DNA PCR assay, the Copas Amplicor Monitor, which has high sensitivity and specificity, demonstrated a good correlation with the clinical situation and with the kinetics of viral load [55–58]. Recently, new applications based on real time PCR technology have been developed.…”