Evaluation of anti-complement immunofluorescence test in cytomegalovirus infection

The anti-complement immunofluorescence (ACIF) technique was evaluated for the diagnosis of human cytomegalovirus (CMV) infection in a group of sera derived from renal transplant recipients and donors by comparing it with the indirect immunofluorescence (FA) and complement fixation (CF) TESTS. The ACIF and FA tests yielded similar results. However, the ACIF test had a distinct advantage over the indirect FA test, since it eliminated the nonspecific cytoplasmic staining that may result in false positive readings in inexperienced hands. Both the indirect FA and ACIF tests were more sensitive than the CF test. In primary CMV infection, the FA and ACIF antibodies appeared earlier and had significantly higher titer than corresponding CF titers. This difference in titers was not seen in seropositive individuals who lacked overt infection. Our previously reported correlation between the seropositivity of the donor and CMV infection in seronegative recipients has been confirmed.